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We observed the distribution of CD56+ epithelial cells in the pancreatic duct system using 25 fetal, one infantile, 3 normal adult, 4 diabetic, and 8 chronically inflamed pancreatic tissue samples. In the early stage of gestation (12 to 17 weeks), CD56+ cells were commonly seen in the immature tubular structures. They were often continuous to pancreatic islets, and their distribution was similar to that of synaptophysin (Syn)+ cells, suggesting that they are precursors of islet neogenesis. Their number decreased in proportion to gestational age. Instead, from 24 weeks of gestation, luminal cell clusters that were common in interlobular ducts revealed CD56+. These cell clusters were unrelated to islet neogenesis and Syn expression. Similar CD56+ luminal cell clusters were also observed in cases of chronic pancreatitis, whereas they were scarce in normal adult and diabetic tissues. CD56+ cells were also occasionally seen in intralobular ducts, intercalated ducts, and centroacinar cells in cases of chronic pancreatitis. We conclude that there are two types of CD56+ epithelial cells in the pancreatic duct system: CD56+ endocrine cells are numerous during the early stage of gestation, when islet neogenesis appears, while CD56+ luminal cells may represent developmental and regenerative changes of pancreatic ducts.

Ocular manifestations in patients with psoriasis vulgaris have been investigated in only a small number of studies. Our purpose was to identify tear film function and ocular pathologies associated with psoriasis vulgaris in patients who had received neither oral retinoids nor phototherapy. We examined 62 eyes of 31 patients with psoriasis and 60 eyes of 30 age-and-sex matched healthy volunteers. In addition to complete ocular and dermatological examination, tear film function (i.e., tear secretion and tear film stability) were assessed by the Schirmer-I test, as well as by tear film break-up time. None of the controls had any ocular abnormalities, whereas 67.74% of patients with psoriasis had various anterior segment pathologies (P<0.00009). The most prevalent finding was chronic blepharoconjunctivitis (64.5%), as the only pathology (n=9) or in association with other findings, including nonspecific corneal opacities (n=4), cataract (n=3), both corneal opacities and cataract (n=2), and corneal pigment dispersion (n=2). The Schirmer-I test results revealed comparable mean values in the patient group (9.8+-4.2 mm) and in the controls (11.2+-3.7 mm; P=0.078). However, mean tear film break-up time was significantly shorter in the patients (7.2+-2.5 sec) than in the healthy persons (11.7+-3.1 sec; P=0.001). In agreement with some previous reports, our findings clearly demonstrated that early ocular involvement occurs in patients with psoriasis vulgaris, irrespective of the history of previous therapeutic modalities (e.g., retinoid therapy and phototherapy). Thus, the present findings are suggestive of the contributory role of primary etiologic factors of psoriasis in the pathogenesis of ocular changes in patients with psoriasis vulgaris.

This study was designed to explore whether it was possible to evaluate the severity of VSD, PDA, and ASD by measuring brain natriuretic peptide (BNP) levels. We also investigated normal BNP levels in children to provide a baseline for our study. We measured BNP levels in 253 normal children, including 11 normal neonates, and in 91 VSD patients, 29 PDA patients, and 34 ASD patients. BNP levels showed no age-related differences in normal children (the mean value: 5.3 +/- 3.8 pg/ml). In the healthy neonates, BNP levels rose from 10.4 +/- 11.9 pg/ml in cord blood to 118.8 +/- 83.2 pg/ml on day 0, then fell to 15.3 +/- 7.8 pg/ml by day 7. In VSD and PDA patients, BNP levels correlated significantly with Qp/Qs, LVEDV, and peak RVP/LVP. In ASD patients, BNP levels correlated with Qp/Qs and RVEDV. Especially, in VSD patients, as an index corresponding to 1.5-2.0 of the Qp/Qs ratio, BNP levels of 20-35 pg/ml were found to be best with regard to both sensitivity and specificity. In the healthy neonates, BNP levels changed rapidly after birth. In VSD, PDA, and ASD patients, BNP levels were well-correlated with the severity of the disease. Especially, in VSD patients, it that appears BNP levels may be useful in evaluating surgical indications, with 20-35 pg/ml levels being the appropriate cut-off value.

Chemical shift MRI is widely used for identifying adenomas, but it is not a perfect method. We determined whether combined dynamic MRI methods can lead to improved diagnostic accuracy. Fifty-seven adrenal masses were examined by chemical shift and dynamic MR imaging using 2 MR systems. The masses included 38 adenomas and 19 non-adenomas. In chemical shift MRI studies, the signal intensity index (SI) was calculated, and the lesions classified into 5 types in the dynamic MRI studies. Of the 38 adenomas studied, 37 had an SI greater than 0. In the dynamic MRI, 34 of 38 adenomas showed a benign pattern (type 1). If the SI for the adenomas in the chemical shift MRI was considered to be greater than 0, the positive predictive value was 0.9, and the negative predictive value was 0.94 and kappa = 0.79. If type 1 was considered to indicate adenomas in the dynamic MRI, the corresponding values were 0.94, 0.81 and kappa = 0.77 respectively. The results obtained when the 2 methods were combined were 1, 0.95 and kappa = 0.96 respectively. The chemical shift MRI was found to be useful for identifying adenomas in most cases. If the adrenal mass had a low SI (0 < SI < 5), dynamic MRI was also found to be helpful for making a differential diagnosis.

Despite the current diagnostic and serologic testing for SLE, the interval between the onset of symptoms and the diagnosis is still long. In this study, we aimed to show the interval between the initial symptoms and the diagnosis of SLE and to investigate the presence of any relationship between the interval and the initial symptoms. One hundred and thirty-six patients were diagnosed with SLE using the 1982 ARA criteria. The mean age of the patients at diagnosis was 29.9 +/- 10.5 years. The mean interval between the onset of symptoms and the diagnosis of SLE was 21.82 +/- 30.32 months. The subjects were evaluated twice, at intervals of < or = 3 and < or = 12 months after the onset of symptoms. Although arthritis and/or arthralgia were the most common initial symptoms (60.3%), only 26.8% of the patients with these symptoms were diagnosed earlier than 3 months after the onset. If the first initial symptoms were butterfly rash or pericarditis, pleuritis, spontaneous abortion or cognitive dysfunction, they led to early diagnosis. In conclusion, since arthritis and/or arthralgia are the most common initial symptoms of the disease, every young woman with these symptoms should be carefully evaluated for SLE.

The purpose of this study was to compare the MR characteristics of renal cell carcinomas against histologic findings and to assess the correlations among signal intensity, tumor enhancement, and pathologic findings. Fifty-four patients (56 lesions) were examined by MR imaging and then underwent partial or radical nephrectomy. The pathologic diagnosis of all lesions was renal cell carcinoma. All MR examinations were performed as dynamic studies using the same 1.5-T scanner. MR characteristics were compared against pathologic findings after resection, and the correlations among signal intensity, tumor enhancement, and pathologic findings were then assessed. A significant correlation was observed between tumor grade and tumor enhancement, with G3 lesions tending to show little enhancement. Regardless of the histologic classification, G3 tumors were found to contain highly heterotypic cancer cells and very few vessels by histopathologic examination. No significant correlations were noted between the other MR characteristics and pathologic findings. Renal cell carcinomas showing little enhancement tend to be highly malignant lesions based on the pathologic findings. Special consideration is required for these tumors with regard to the selection of surgical intervention and follow-up observation.

We studied the association of gamma-glutamyltransferase (GGT) and other serum markers of liver injury with daily alcohol consumption in a healthy population of 1,043 Japanese males. A positive correlation between daily alcohol consumption and biochemical markers, such as log GGT (r = 0.432), log AST (r = 0.244) or log LAP (r = 0.246), was seen in all drinkers. However, there was a negative correlation, such as log GGT (r = -0.434), log AST (r = -0.424) or log LAP (r = -0.430), in heavy drinkers who consumed more than 70 g ethanol a day. On the other hand, a positive correlation, such as log GGT (r = 0.426), log AST (r = 0.247) or log LAP (r = 0.216) was found in moderate drinkers who consumed less than 70 g ethanol a day. Interestingly, there was a tendency toward negative association between alcohol consumption and the Tokyo University ALDH2 Phenotype Screening Test (TAST) score in the heavy drinkers, and there was a tendency toward positive association between GGT and TAST score in this group. Our results suggest that there are 2 groups of drinkers, those with elevated GGT (good responders) and those with normal GGT (poor responders) despite heavy drinking.

We observed a bilateral and symmetrical variation of the anterior belly of the digastric muscle during the dissection of a 35-year-old female cadaver. The accessory muscle bundles were arranged in a cross. These bundles were found superficial to the mylohyoid muscle and deep in the platysma. Such a variation from perfect symmetry has not been previously reported. To avoid misinterpretation of radiological tests, it is important to be aware of bilateral and symmetrical variations of the anterior belly of the digastric muscle when examining the floor of the mouth and the submental region.

The purpose of this study was to elucidate the role of extracellular matrix components such as aggrecan, fibronectin, and laminin in the extraocular muscle of patients with strabismus. Resected tissues of the medial rectus muscle of 47 patients with intermittent exotropia obtained during recession-resection surgery were frozen under liquid nitrogen and pulverized by a Freezer/Mill to solubilize the tissue for enzyme immunoassay. The total amounts of aggrecan, fibronectin, and laminin in the resected tissue were correlated with clinical data of patients such as age, exodeviation, and refractive error. The amount of aggrecan decreased significantly with the advance of age (P < 0.0001, Spearman rank correlation test), while the amount of laminin or fibronectin had no correlation with age. Patients with basic type intermittent exotropia showed larger, although not significantly, amounts of aggrecan than those with convergence insufficiency type (P = 0.0538, Mann-Whitney U-test). The amount of aggrecan may be related to motor aspects of intermittent exotropia.

1) It has been found that the peripheral blood of hybrid adult dogs contains about 29.4 % of lymphocytes in average. When such a blood is passed through the glass wool column the leucocytes containing 68-90 % (81.6% in average) lymphocytes are obtained. 2) In the single culture of such lymphocytes alone and mixed culture both live lymphocytes and sonicated lymphocytes in the presence of 1% (vIv) PHA, the peak of the blastformation of lymphocytes is observed at culture hour 72. 3) In the abscence of PHA both single culture and mixed culture of lymphocytes show hardly any blastformation. 4) In the mixed culture of live lymphocytes with homogenate of sonicated lymphocytes with addition of 1% (vIv) PHA the rate of blast. formation observable at culture hour 72 and the rejection of kidney trans· plant 7 days after its transplantation of hybrid adult dogs show a direct correlation, demonstrating that the mixed lymphocyte reaction reflects accurately the difference in donor histocompatibility antigens against the recipient.

Eine Salieyl-Chinin-Lithium-Kombination wurde im Siemens Unterriehtsreaktor SUR 100 BE des Instituts fur Kernteehnik der Teehnisehen UniversiUit Berlin mit Neutronen aktiviert. AnsehlieBend erfolgte die Messung der spektralen Verteilung der Gamma-Zahlrate zu zwei versehiedenen Zeitpunkten naeh der Aktivierung. Es wird festgestellt, daB diese Salieyl-Chinin-Lithium-Kombination nur sehwaeh im SUR-Reaktor aktivierbar ist, vergliehen mit einer Goldsonde etwa 200 mal sehwaeher. Trotzdem konnten mit Hilfe eines 400-Kanal-Analysators die spektralen Verteilungen der Gamma-Energien dieses Praparates noch sehr genau bestimmt werden. Ein ausgepragter Gamma-Peak tritt auf bei der Energie 0.53 MeV. Er klingt ab mit einer Halbwertszeit von 1.6 h und ist vermut· lich auf ein Element der Tablettierhilfsstoffe zurUckzufUhren. Vom strahlenphysikalischen Gesichtspunkt ist das Praparat fUr die Human. medizin gut geeignet.

The role of -SH groups in mitochondrial energy transfer reaction was studied by observing the reduction of a disulphide, 5, 5'-dithiobis (2-nitrobenzoic acid), DTNB, a specific analytical agent for the estimation of -SH groups in biological materials, by addition of it to the isolated rat liver mitochondria in various respiratory states, as defined by CHANCE and WILLIAMS. 1. In the various respiratory states, states 1 to 5, the reduction of DTNB proceeds most rapidly at state 5, and most slowly at state 3. DTNB reduction at state 5 is suppressed by the partial oxidation of respiratory carriers with oxygen (state 4) and the addition of respiratory substrate does not affect the DTNB reduction. 2. The retardation in the reduction rate at state 3 is relieved partially by a respiratory inhibitor, KCN, and is intensified markedly by oligomycin, an inhibitor of oxidative phosphorylation. An uncoupler for oxidative phosphorylation, DNP, does not affect the reduction rate at state 3. At state 4 the reduction is stimulated by DNP and KCN, but is unaffected by oligomycin. The results suggest that the alteration in the functions of the energy transfer reaction in mitochondria is accompanied by changes in the occurrence and the functioning of -SH groups which can be detected by the reactivity with DTNB. The data suggest also that there are at least two kinds of -SH groups reacting with DTNB: the one is the -SH group which reacts DTNB actively when the respiratory carriers are kept reduced, and the other is the one which reacts actively when the respiratory carriers are kept oxidized, participating in the phosphorylating system and its reactivity with DTNB diminishes in the actively phosphorylating states (states 2 and 3).

With the purpose to clarified the mode of localization and mechanisms of activation of ATPase in the mitochondrial membrane, analyses were made on the properties of mitochondrial ATPase from the structural and functional aspects. The activation of ATPase by DNP and Mg++ and the oligomycin sensitivity were investigated in a series of inner membrane fragment samples obtained by ultrasonic irradiation and those samples obtained in the processes of isolation and purification of ATPase from rat liver mitochondria and beef heart mitochondria in parallel with electron microscope observations. As a result it has been found that the membrane fragments obtained from rat liver and beef heart mitochondria by ultrasonication exhibited high respiratory activity and unmasked ATPase activity which was charac· terized by remarkable stimulation by Mg++ and inhibition by oligomycin and azide. Therefore, mitochondrial ATPase seems to be bound fairly closely to the inner mitochondrial membrane. In the membrane fragments prepared by ultrasonication of intact mitochondria, ATPase activity was stimulated by DNP, but in the supernatant fractions was not. On the other hand, the supernatant fraction obtained from BHM and inner membrane fragments by severe sonication exhibits a marked ATPase activity and the activity incresed in each step of the purification on the treatments with acid, protamine and heat. Especially in the case of membrane fragments the protamine treatment can be omitted. Electron microscope observation of the fractions in each step of the purification proved the head pieces to be ATPase. The ATPase activity of solubilized head pieces is insensitive to oligo. mycin and coincides with the soluble ATPase of PULLMAN etat. (8) in the points of its cold labile property and optimum pH, but it shown no accele. ration of ATPase activity by DNP.

For the purpose to obtain the information of the mechanism of protein uptake by the tumor cells, some cytochemical and electron microscopic observations were carried out on Ehrlich ascites tumor cells incubated with horseradish peroxidase (basic hemoprotein, molecular weight approximately 40,000) in vitro. In the earlier periods of the incubation peroxidase was found to be adsorbed on some area of surface of the tumor cells forming a thin protein layer, where an active pseudopodia formation was observed. With the lapse of time, the protein was taken in the deep cytoplasm by the infoldings of the cell membrane and accumulated in the cytoplasmic vesicles having limiting membrane. Concerning the accumulation of the protein into the vesicles, small tubular structures in the cytoplasm connecting the cell surface and the vesicles, were considered to participate in the intracellular transportation of peroxidase taken up. In cold environment (2°C), the formation of pseudopodia and deep inward infoldings of the cell membrane was inhibited and simultaneously the uptake of peroxidase stopped. Iodoacetate and sodium fluoride also effected to suppress the pseudopodia and infoldings formation moderetely, as well as uptake of peroxidase, though they did not stop completely. These facts have indicated that horseradish peroxdase is taken up by Ehrlich ascites tuimor cells through pinocytosis which involves energy-requiring process dependent upon glycolytic metabolism of the tumor cells.

For the purpose to reveal the changes in the metabolism of erythroblast in varied specialization stages the author observed the Feulgen DNA level of rabbit erythroblasts by microspectrophotometry. Observations were made on normal and anemic animals, and those receiving a mass red cell transfusion at the recovery stage of anemia where the early denucleation is stimulated. Observations have revealed that in normal erythropoiesis the DNA contents are kept at n to 2 n level from the proerythroblast to late basophilic stage, but in later stages, polychromatic and orthochromatic, DNA level per cell decreases gradually with advance of the cell specialization reaching the minimum level, nearly haploid level, at orthochromatic stage where most cells are believed to be denucleated. In blood depleted animals nearly the same pattern of DNA level was observed in connection with erythroid specialization as that in normal animal, except a relatively high DNA level in the later specialization. In the cases of the hemolytic anemia a similar tendency has been observed but the minimum level of DNA remains at a higher level, hypo-diploid level, in poly- and orthochromatic stages. Twenty-four hours after the mass red cell transfusion by which severe anemia has been recovered to the original level within one hour, the pattern of the DNA level of the erythroblast returns to the normal one showing a very low DNA level at the polyand the orthochromatic stages. The data indicate that the DNA synthesis of erythroblast kept at n to 2 n levels until the late basophilic stage begins to decline at polychromatic stage and reaches nearly haploid level at orthochromatic stage, but in active hemopoiesis the DNA synthesis is stimulated and the DNA contents are kept at a high level even in the late specialization stages, showing no relation between the denucleation and the low DNA level.

Localization of IgM and IgG sypylitic antibodies in the sera of patients and the experimental syphylitic rabbits was examined by the gel filtration on Sephadex G.200 column. I) In the case of late syphylitic patients; OGATA test-reactive antibodies were contained in IgM and IgG fractions. On the other hand, RPCF test-reactive antibody was contained only in IgG fraction. This discrepancy may be due to the difference in antigens; Cardiolipin.resicin and T. P. Reiter protein. 2) In the case of the experimental syphylitic rabbits; The results were as follows. a) Variation in the level of the titer. The peaks of the titer were seen 3-4 weeks after inoculation of T. P. Nichols by OGATA test, VDRL test and RPCF test, thereafter titers decreased. On the other hand, the titer kept on rising up to 2 months and maintained high level during the periods of 3, 4 and 5 months by TPHA test. b)Transformation of antibody from IgM to IgG. Transformation of antibody from IgM to IgG was seen 3-4 weeks after inoculation by all four tests; OGATA test, VDRL test, RPCF test and TPHA test, and such a transformation was completed 3 months after inoculation.

1) Normal karyotype of Donryu strain rat was determined according to the classification of KURITA et al. (8). Namely, the number of chromosomes was 42 in diploid cells, and chromosomes were divided into 3 groups (A, B and C) according to the position of centromere. A.group was consisted of 7 pairs of metacentric chromosomes, B-group 4 pairs of sub· meta.subtelocentrics and C.group 10 pairs of telocentrics and Y. 2) Among all chromosome pairs a pair of the longest telocentric chromosomes (C.l), 4 pairs of all the B.group, and the Y chromosome were recognizable. 3) The presence of polymorphism was demonstrated in the smallest submetacentric chromosomes (BA),: namely, (I) a homologous submeta. centric pair, (II) a homologous subtelocentric pair and (III) a heteromor. phic submeta and subtelocentric pair which seemed to be a hybrid from (I) and (II). To distinguish the polymorphism in their genotype from phenotype was impossible. 4) Animals with type III B·4 chromosomes were produced by type I and type II animals. 5) By checking the chromosomes of the inbred Donryu strain rats maintained over 40 generations by brother.sister mating at Nihon Rat Co., polymorphism in BA chromosomes was also recognized.

Female Cb mice weighing 20-23 g were exposed to 800 ppm (in average) of 1, I, 2, 2.tetrachloroethane for 3 hours. Both triglyceride and phospholipid in the liver and plasma were determined at varying times after the exposure. On the other hand, there were observed the ultraviolet absorption spectra of microwmallipids in the liver at 90 minutes after the 1, 1,2, 2-tetrachloroethane or the carbon tetrachloride exposure. The results thus obtained are summarized as follows: 1. The increase of hepatic triglyceride contents attained the maximum level in the period between 20 and 25 hours after the exposure and declined to the initial levels at 90 hours later. 2. The plasma triglyceride levels decreased until 25 hours after the exposure, then tended to increase significantly and were much higher than the control levels in the period between 70 and 90 hours later. 3. Both liver and plasma phospholipid levels decreased gradually up to 25 hours after the exposure, then slowly recovered with almost the same rate of increase. 4. It was suggested that the inhalation of the above vapors induced a little change in microsomal lipids in the liver.

For the purpose of forecasting the prevalence ofJapanese encephalitis in Japan, we tried to find out the correlation of factors between median and mode dates of epidemic time curve of prevalence on one hand, and average atmospheric temperatures of prefectures in June and July (T6,7 in short) (X¹), the time when HI reaction of swine became positive to the degree of 50 per cent (D. pos. swine in short) (X²), the latitude (x³) and longitude (x4) in respective prefectures (in 1965 and 1967). On the other we also estimated the median and mode dates of this epidemic curve of the prevalence in 1968 and 1969, from the regression equation of one variable and multiple regression equation from the above factors using an electronic computer. The usefulness of adding factors concerned with mosquitoes to the above four factors is proven by the accuracy of estimation. And the following results were obtained. 1) Phenomenally speaking, the prevalence of Japanese encephalitis follows the principle of "advancing of prevalence towards the north and east" and essentially speaking, it depends upon high atmospheric temperature and the outbreak of many hazardous mosquitoes by the high atmospheric temperature. 2) To estimate median date (y) and mode rate (z) of the epidemic time curve of the prevalence, we can use the next equations; The regression equations to estimate y and z from T 6,7(X) are as follows. y = - 3. 75X¹ + 144.47 σ = 12.4.·. [1] z = - 3. 80X¹ + 157 .26 σ = 14.9.. · [1]' The regression equation from D. pos. swine (X²) are as follows. y = 0. 68X² + 31. 82 σ = 9.2· .. [2] z=0. 76X² +40. 71 σ= 12.0 .. · [2]' The multiple regression equation from T6 ,7 and D. pos. swme are as follows. y = -1. 07X¹ +0 .62x² +59. 37 σ= 9.7 ... [3] z= -0. 79x¹ +0. 71x² +61.02 σ= 12.0· .. [3]' The multiple regression equations from T 6•7, D. pos. swine, latitude and longitude are as follows Y= -1.01x¹ +0.58x² -0.26x³+0 .37x4 + 18.50 σ= 9.8･･･ [4] z = -0. 32x¹ +0. 52x² +2 .05x³ +0 .54x4 -87. 81 σ= 11.8 [4]' 3) We Obtained the estimated value of median date in 17 prefectures in Kyushu, Chugoku, Shikoku, Kinki and Kanto provinces in 1968 and in 13 prefectures in 1969 from [l] or [2] or [3] or [4] equation. Nine prefectures out of 17 by [l], 12 prefectures by [2], 13 by [3J and [4] in 1968. [4] could be estimated with about 10 days error or less. And in 1969, 9 out of 13 by [3] and 7 out of 13 by [4] could be accurately esti· mated. The estimation by the multiple regression equation using many factors is most useful for the calculation. 4) The time when the number of patients increases at maximum can be pointed out by the lower limit of prediction region obtained from data in each prefecture. And the lower limit was the estimated median value minus about 20 days by [1] and about 16 days by [2] or [3] or [4] under the next condition; α = 0. 1, N= 75. 5) The mode dates in 17 prefectures out of 19 were estimated by [1]', [2]', [3]' and [4]'. 12 prefectures out of 17 by [1]', 7 by [2]', 10 by [3]' and 13 by [4]' could be estimated with about 12 days error or less in 1968 and 9 out of 13 was correctly estimated by [3]' and [4]' in 1969. The estimation by the regression line of one factor was s~mewhat different from each other, but when multiple regression line of four factors was used the estimation became more correct. Judging from these results, it is adequate to use the multiple regression equation of [4] and [4]' when we want to forecast the median date or mode date ofJapanese encephalitis time cure. 6) In the case of adding two factors concerned with mosquitoes to T6,7 (X¹), D. pos. swine (x²), latitude (x³), longitude (x4), multiple regression equations become as follows. y= -1.46x¹+0.14X²+0.068x5+89.03 σ= 6.9.. ·[5] z= -3. 29x¹+0 .13x²-0. 010x5+ 143.63 σ= 18.6··· [5]' y=-4.20x¹+0.35x²+0.29x6 + 53.70 σ= 4.2 .. ·[6] z=-2.56x¹-0.0lx²-0.02x6 +128.96 σ=11.4 [6]' y= 4.76x¹+0.41x²+0.13x5+0.22x6-72.78 σ= 4.5 [7] z = - 2. l0x¹ + 0. 05x²+ 0. 11 x5 - 0. 08x6+ 113.4 σ= 10. 7.. · [7]' where x5 is the time when the number of mosquitoes (C. T. collected by light trap reached the maximum and X6 is the time when hazardous mosq uitoes were dected. In the case of median date, 5 prefectures out of 6 prefectures by [5], 2 out of 6 by [6] and 2 out of 5 by [7], and in the case of mode date, 5 out of 6 by [5]', 4 out of 5 by [6]' and 4 out of 5 by [7]' could be accurately estimated in 1969.