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51.
We developed a lung sound auscultation simulator "Mr. Lung" in 2001. To improve the auscultation skills of lung sounds, we utilized this new device in our educational training facility. From June 2001 to March 2002, we used "Mr. Lung" for our small group training in which one hundred of the fifth year medical students were divided into small groups from which one group was taught every other week. The class consisted of ninety-minute training periods for auscultation of lung sounds. At first, we explained the classification of lung sounds, and then auscultation tests were performed. Namely, students listened to three cases of abnormal or adventitious lung sounds on "Mr. Lung" through their stethoscopes. Next they answered questions corresponding to the portion and quality of the sounds. Then, we explained the correct answers and how to differentiate lung sounds on "Mr. Lung". Additionally, at the beginning and the end of the lecture, five degrees of self-assessment for the auscultation of the lung sounds were performed. The ratio of correct answers for lung sounds were 36.9% for differences between bilateral lung sounds, 52.5% for coarse crackles, 34.1% for fine crackles, 69.2% for wheezes, 62.1% for rhonchi and 22.2% for stridor. Self-assessment scores were significantly higher after the class than before. The ratio of correct lung sound answers was surprisingly low among medical students. We believe repetitive auscultation of the simulator to be extremely helpful for medical education. 相似文献
52.
DNA damage triggers imbalance of proliferation and apoptosis during development of preneoplastic foci in the liver of Long-Evans Cinnamon rats 总被引:5,自引:0,他引:5
The mutant strain Long-Evans Cinnamon (LEC) rat accumulates copper, resulting in spontaneous hepatitis and subsequent development of hepatocellular carcinomas (HCCs) in the liver, providing a promising model for investigation of the relationship between hepatitis induced by oxidative stress and hepatocarcinogenesis. We examined DNA strand breaks in peripheral blood cells and p53 expression in livers during acute and chronic hepatitis in LEC rats, along with preneoplastic lesions, and cell proliferation and apoptosis in non-cancerous portions of livers from LEC rats aged 7-115 weeks. Immunohistochemistry using antibodies against glutathione S-transferase placental-form (GST-P), proliferating cell nuclear antigen (PCNA), and in situ DNA nick labeling (TUNEL) were used. Long-Evans Agouti (LEA) rats, a sibling line of the LEC strain, were used as controls. In the LEC rats, DNA strand breaks and expression of p53 were significantly higher than that of LEA rats at 24 weeks of age. The number of GST-P-positive (GST-P+) foci/cm2 increased and peaked at 48 weeks old, and the areas rapidly expanded thereafter. The level of cell proliferation increased with the development of hepatitis and was highest at about 48 weeks old. The induction of apoptosis in LEC rats was transiently higher than that in LEA rats during the period from 24 to 34 weeks of age. However, the ratio of PCNA-positive cells to the apoptotic index showed a growth imbalance in favor of cell proliferation, supporting sustained net growth in LEC rats. These findings suggest that DNA damage, reflected in DNA strand breaks, plays a critical role in the development of hepatocellular preneoplastic foci, with an imbalance between high proliferation and relatively low apoptosis. 相似文献
53.
This study examined differences in measures of perception of body shape and body satisfaction among 25 male and 165 female undergraduates. The students completed a body image questionnaire, comprised of four parts: (1) anthropometric data; (2) figure rating scale; (3) cognitive attitude toward body size; and (4) satisfaction with body characteristics. This study found that male ratings of the Ideal figure, the figure of how they currently thought they looked, and the figure of how they felt most of time were almost identical, as were the figure of what they thought most attractive to women and the figure of how they thought others saw them. On the contrary, female ratings of the Ideal figure were significantly thinner than their perception of their current figure, the figure as others saw them, and the figure they felt most of time. Furthermore, the female figure that women rated as most attractive to males was thinner than the figure that males actually preferred. On the other hand, male judgments of the male figure most attractive to females were heavier than female ratings of the same. Both males and females erred in estimating what the opposite sex would find attractive. Males overestimated and females underestimated the body size attractive to the other sex. Although over half of the male and female subjects reported their body size as 'In-between', more males wanted to gain weight and more females wanted to lose weight to present their Ideal body shape. Furthermore, males were biased toward being satisfied with their body and females were biased toward being dissatisfied with their body. Additionally, the number of females satisfied with hands and dissatisfied with upper thighs and buttocks was higher than that of males. 相似文献
54.
Oral L-arginine prevents murine coxsackievirus B3 myocarditis 总被引:1,自引:0,他引:1
We have previously demonstrated that administration of nitric oxide (NO) synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), aggravated murine coxsackievirus B3 myocarditis. In the present study, we evaluated the effects of L-arginine, a precursor of NO, upon acute and chronic myocarditis. Dietary L-arginine and L-arginine plus L-NAME (L-arginine+L-NAME group) were administered to coxsackievirus B3 (CB3)-infected C(3)H/He mice for 2 weeks (experiment I), and to CB3-infected mice from the second week until the fourth week after virus inoculation (experiment II). Infected control was prepared in each experiment. In experiment I, survival was higher in the L-arginine group compared with the other two groups, and cardiac damage was less. In addition, plasma concentrations of L-arginine and NO were elevated in the L-arginine group. In experiment II, cardiomyopathic lesion in the L-arginine group was less prominent associated with lower plasma catecholamine and lower myocardial collagen concentrations compared with the other two groups. Thus, L-arginine treatment may be effective not only in preventing the development of acute CB3 myocarditis but in ameliorating cardiac dysfunction in chronic myocarditis. 相似文献
55.
Kraft NO Inoue N Mizuno K Ohshima H Murai T Sekiguchi C 《Aviation, space, and environmental medicine》2002,73(2):85-90
PURPOSE: Cultural and personal traits will become important as the number of short-duration spaceflights of international crews supporting the International Space Station (ISS) increases and more people begin staying aboard ISS for longer durations. This project investigated the interpersonal and personal changes of Japanese subjects during a 1-wk stay in the Japanese Experiment Module. The Giebetaen Test (GT) was used to determine if the cultural background and personality traits of the subjects become more explicit and stronger during isolation. METHODS: Six males and two females aged 22-28 yr participated in the study. They stayed 7 d in the isolation chamber at the National Space Development Agency of Japan (NASDA). The GT was chosen as an individual and group diagnostic instrument; it was administrated four times during, and one time after, isolation. RESULTS: According to the GT-self-picture, subjects exhibited a change toward negative social resonance and social withdrawal. Subgroups formed but caused no isolation or tension. The GT-foreign-pictures showed that the judgment of other subjects changed toward hedonic and permeability directions. The common interpersonal relationships of the Japanese subjects influenced the group dynamics. These relationships tend to be integrative and tend to support the network and value systems, emphasizing connectedness and minimizing differences. CONCLUSION: The cultural background became more explicit and stronger during isolation. Based on this, isolation studies with international crews and intercultural training will be necessary for international crews performing both short- and long-duration missions. 相似文献
56.
Elevated level of plasma basic fibroblast growth factor in multiple myeloma correlates with increased disease activity. 总被引:5,自引:0,他引:5
Norihide Sato Yutaka Hattori Du Wenlin Taketo Yamada Tamihiro Kamata Tsunayuki Kakimoto Shinichiro Okamoto Chiharu Kawamura Masahiro Kizaki Naoki Shimada Yukiko Ote Jun-ichi Hata Yasuo Ikeda 《Japanese journal of cancer research》2002,93(4):459-466
Recent reports that bone marrow angiogenesis is increased in multiple myeloma prompted us to examine plasma concentrations of angiogenic growth factors and to elucidate their clinical and biological significance. In 45 cases including 36 cases of multiple myeloma and 9 cases of monoclonal gammopathies of undetermined significance (MGUS), plasma concentrations of basic fibroblast growth factor (FGF-2) and vascular endothelial growth factor (VEGF) were evaluated. FGF-2 was significantly elevated in 25 out of 45 (56%) of the patients with multiple myeloma compared with control subjects (median 9.01 pg ml vs. 1.58 pg/ml, P < 0.0001). The 25 cases were all active multiple myeloma, and none of the non-active myeloma and MGUS patients showed a high FGF-2 level. VEGF level was also elevated in 26 out of 45 patients (58%) compared with control subjects (median 42.0 pg/ml vs. 15.8 pg/ml, P < 0.0001 for VEGF). VEGF concentration was high in 20 active myelomas, but also in one non-active myeloma and five MGUS. Elevation of FGF-2 level was associated with beta2-microglobulin level, anemia and bone marrow plasma cell percentage, which represent disease activity. Interestingly, none of five Bence-Jones type myelomas, including four clinically active cases, revealed a high plasma FGF-2 level, while all of them showed a high VEGF level. In all five responders, the plasma FGF-2 levels were significantly decreased after chemotherapy. FGF-2 was immunohistochemically detected in the bone marrow myeloma cells of the patients with high plasma FGF-2 level. We conclude that plasma concentration of FGF-2 can be a useful indicator of disease activity. 相似文献
57.
Ikeda M Mitsui T Setani K Tamura M Kakeyama M Sone H Tohyama C Tomita T 《Toxicology and applied pharmacology》2005,205(1):98-105
The effects of in utero and lactational exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on brain sexual differentiation were investigated. TCDD was orally administered to pregnant Holtzman rats on gestation day (GD) 15, and the activity of brain aromatase, a key enzyme for sexual differentiation, was measured in offspring on postnatal day (PND) 2. Changes in sexual dimorphisms of saccharin preference and the volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) were examined in adult offspring. In controls, litter means of brain aromatase activity were higher in males than in females. In utero exposure to 200 ng/kg TCDD significantly decreased the sex ratio of aromatase activity (male/female) on PND 2. Offspring were weaned on PND28 and the saccharin test was started on PND84. In controls, saccharin (0.25%) intake (g/kg body weight) was significantly higher in female offspring than in males. In utero exposure to 200 ng/kg TCDD significantly increased saccharin intake in male offspring compared with control males, whereas 800 ng/kg TCDD had no effect. Neither dose of TCDD influenced saccharin intake of female offspring. In controls, SDN-POA volume was significantly greater in males than in females at 14 weeks of age. Exposure to 200 ng/kg TCDD significantly decreased SDN-POA volume in males, whereas 800 ng/kg TCDD had no effect. Neither doses of TCDD influenced the SDN-POA volume in female offspring. These results suggest that in utero and lactational TCDD exposure dose-dependently induces demasculinization in male offspring by inhibiting brain aromatase activity in the hypothalamus-preoptic area during central nervous system development. 相似文献
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