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61.
The effect of physical training on the cutaneous vascular response during transient exercise load is unclear. We determined the phase response and amplitude response of cutaneous vascular conductance (CVC) in the hand during sinusoidal exercise in endurance exercise-trained and untrained subjects. Subjects exercised on a cycle ergometer with a sinusoidal load for 32 min. The load variation ranged from 10% [23 (1) W in the trained group, 19 (1) W in the untrained group] to 60% [137 (4) W, 114 (6) W] of peak O2 uptake, and five different time periods (1, 2, 4, 8, and 16 min) were selected. Skin blood flow in the dorsal hand and palm were monitored by laser-Doppler flowmetry. CVC was evaluated from the ratio of blood flow to mean arterial pressure. During sinusoidal exercise, the amplitude of CVC was smaller in the dorsal hand than palm for shorter periods (1, 2, and 4 min) (P<0.05). The phase lag of CVC was smaller in the dorsal hand than palm for longer periods (8 and 16 min) (P<0.05). The amplitude response did not differ significantly between the two groups. The phase lag of CVC in the dorsal hand (P<0.05) and palm (P=0.06) was larger in the trained group than untrained group. These findings suggest that glabrous and nonglabrous skin vascular responses in the hand differ during transient exercise load, and physically trained subjects show a slower vascular response in the two skin areas to exercise stimulation than do untrained subjects.  相似文献   
62.
Several reports have suggested that the prevalence of asthma in adults is currently increasing. However, recent prevalence of asthma has not reported in Japan, especially in rural-mountain areas. To investigate the prevalence of asthma in adults in Japan, we conducted clinical epidemiological research on 5066 inhabitants of Menda town, in a rural-mountain area of Japan. The study population comprised 98.7% of adults in the town, including senior high school students whose age were more than 15 years old. The prevalence of asthma among adults was 3.6%. The ratio of prevalence in males to prevalence in females was 1.44. Peaks prevalences were observed in the age ranges of 15-19 and > 70 years old in males, and 15-19, 40-49 and > 70 years old in females.  相似文献   
63.
Five cases of adenomatous goiter have been studied by an electron microscope using an immuno-reaction for thyroglobulin (TG) and focusing on the mechanism of endocytosis. Positive stain for TG was demonstrated in follicular lumina, large reabsorbed colloid droplets and small subapical vesicles. Endocytotic vesicles ranging from 320 nm to 1600 nm in diameter were observed in the cytoplasm as pits in the apical plasma membrane. Some of them showed direct connection with the positive stain for TG in the follicular lumen and the others were completely ingested in the cytoplasm. With statistic analysis, a majority of the vesicles showing the positive stain for TG in the cytoplasm distributed in the range of 200 nm to 1200 nm in diameter with the peak in 300 nm to 399 nm and was situated within an extent of the diameter measured from the endocytotic vesicles. Engulfment of colloid by pseudopods and fusion of the reabsorbed colloid droplets were encountered as extremely rare findings and appeared to play no major role for formation of large colloid droplets in adenomatous goiter.  相似文献   
64.
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen.  相似文献   
65.
Muddy lung     
A 31-year-old man, a racing car driver, was submerged in muddy water as the result of an accident. He died from respiratory failure after a 17-day clinical course. Foreign body granulomatosis and massive fibrosis of the lung were revealed at autopsy. The crystalline foreign bodies mainly were composed of silicon and ranged in size from 20 micron to 500 micron in diameter (average, 90 micron). Their distribution in the lungs corresponded to the areas of lung carnification. In this study, the authors demonstrate that near drowning in muddy water causes pulmonary silicate granulomatosis associated with carnificating fibrosis of the lung and term the pulmonary changes "muddy lung."  相似文献   
66.
508 Japanese patients with chronic liver disease, including chronic hepatitis, cirrhosis and hepatocellular carcinoma, and 500 controls matched for sex and age were studied. Antibody to hepatitis C virus (anti-HCV) alone was found in 233 (45.9%) patients and hepatitis B surface antigen (HBsAg) alone was present in 128 (25.2%) patients. Both anti-HCV and HBsAg were present in 18 (3.5%) patients. Anti-HCV was found in 8 (1.6%) controls and HBsAg was present in 4 (0.8%) controls. The prevalence of anti-HCV alone was 36.9% in chronic hepatitis, 49.0% in cirrhosis and 67.0% in hepatocellular carcinoma, respectively. The prevalence of anti-HCV increased with the progress of severity of liver disease. Anti-HCV was more prevalent than HBsAg both in cirrhosis and hepatocellular carcinoma (p less than 0.001). The prevalence of anti-HCV increased with age. Among patients under age 39 years, HBsAg was detected more often than anti-HCV, however, in those over age 50 years, anti-HCV was detected more often than HBsAg (p less than 0.001). It would appear that hepatitis C virus more than hepatitis B virus is a prominent cause of chronic liver disease among Japanese patients.  相似文献   
67.
The effects of high and low dietary fat (20% vs. 0.5% corn oil), and of the prostaglandin synthetase inhibitor indomethacin (0.005% w/w), on tumour incidence, tumour growth, hormone-receptor status and growth-factor expression were examined in dimethylbenzanthracene (DMBA)-induced rat breast cancer. The high dietary-fat group showed a significantly higher tumour incidence, larger tumour size and larger number of bromodeoxyuridine(BrdU)-positive cells of tumours as compared with those in the low dietary-fat group. Indomethacin reduced tumour incidence significantly, but conversely increased the tumour size and the number of BrdU-positive cells in both the high and the low dietary-fat groups. No significant difference was noted in the hormone-receptor status of the tumours. Growth factors (TGF-alpha and IGF-II) were somewhat highly expressed in the high dietary-fat group as compared with the low dietary-fat group, but indomethacin rather reduced the growth-factor expression. It is concluded that high dietary fat stimulates tumour incidence and tumour proliferation, while indomethacin has dual effects: a stimulating effect on tumour proliferation, but an inhibiting effect on tumour incidence. It is also suggested that hormone-receptor status and growth-factor expression do not play an important role in their stimulating effects on tumour proliferation.  相似文献   
68.
An electron microscopic immunohistochemical localization of thyroglobulin (TG) using PAP methods has been made in 15 cases of cold follicular adenoma. All cases of follicular adenoma showed organ specific functions such as synthesis, storage, reabsorption, and hydrolysis of thyroglobulin except for an area composed of follicular cells with trabecular arrangement. Immuno-reaction product for TG was precisely demonstrated in follicular lumina, subapical vesicles and reabsorbed colloid droplets. The reaction product observed in the follicular lumen was clearly demarcated from the cytoplasm of the follicular cells by the apical plasma membrane. The subapical vesicles ranging approximately from 50 mμ to 300 mμ in diameter were rarely observed in follicular adenoma and some of them fused with the reabsorbed colloid droplets. The reabsorbed colloid droplets usually had the intense reaction product and hydrolyzed colloid droplets had a vacuole containing floccular low electron dense materials. There is no reaction product in rough endoplasmic reticulum and Golgi complexes.  相似文献   
69.
During thymocyte development, T-cell receptor (TCR) alphabeta-mediated intracellular signals can elicit two entirely different cellular responses: positive selection (resulting in rescue from death and maturation or differentiation) and negative selection (induction of apoptosis). Here, Hiroshi Nakajima and colleagues discuss how survival signals that are dependent on the common cytokine receptor gamma chain (gammac) might affect the TCR-driven selection process in thymocytes, underscoring the potential role of cytokines in this process.  相似文献   
70.
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