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21.
22.
Three familial cases of drug-resistant Mycoplasma pneumoniae infection   总被引:1,自引:0,他引:1  
Mycoplasma pneumoniae infection is believed to result from defective host immune response rather than from direct cell injury by the organism itself. In this context, emergence of drug-resistant M. pneumoniae may provide us with special opportunities to study the pathogenesis from a clinical point of view. In this report, three patients with intrafamilial M. pneumoniae infection are presented. M. pneumoniae was isolated with a Hayflick pleuropneumonia-like organism diphasic medium. Minimal inhibitory concentrations of antibiotics were determined by a broth microdilution method. Polymerase chain reaction and restriction fragment length polymorphism analysis were done to determine point mutation in domain V of the 23S rRNA gene. As a result, all three strains from the three intrafamilial cases had the same drug-resistant point mutation, specifically A-to-G transition at position 2063. However, their clinical courses were quite different; a 6-year-old girl suffered severe pneumonia, a 5-year-old girl had mild pneumonia, and a 3-year-old boy had only a fever of 1-day duration without pneumonia. Conclusions: Our clinical and laboratory observations strongly support the idea that the host immune maturity, rather than a virulence factor of the organism, is a major determinant factor of disease severity of M. pneumoniae infection and that drug resistance does not necessarily lead to a serious clinical outcome.  相似文献   
23.
Monkey eyes are useful for ophthalmologic research into eye diseases because their histological and functional properties are very similar to those of humans. The monkey laser-induced high intraocular pressure (IOP) model is a common model for ophthalmologic research, especially into glaucoma. Although several studies using this model have focused on changes in visual field, retinal ganglion cells (RGC), and lateral geniculate nucleus (LGN), clear relationships among these changes in one and the same monkey have not been established. We therefore examined visual field changes, RGC and LGN numbers, and glial fibrous acidic protein (GFAP) immunohistochemistry in the LGN in each of two monkeys. Visual field sensitivity, RGC number, and neuronal density of LGN were all decreased by high IOP. The relationship between loss of RGC and decrease in visual field sensitivity depended on the eccentricity from the fovea. Moreover, LGN immunohistochemistry revealed greater increases in GFAP expression in the layers receiving a neuronal input from the high IOP eye than in those receiving a neuronal input from the contralateral untreated eye. From these results, we suggest that glaucoma may lead to changes in glial function not only in the retina, but also in the visual pathway, and that such central nervous system changes may be a hallmark of neuropathy in glaucoma, as in other neurodegenerative diseases.  相似文献   
24.
This study aims to evaluate whether the pattern of socioeconomic inequalities in physical and mental functioning as measured by the Short Form 36 (SF-36) differs among employees in Britain, Finland, and Japan and whether work characteristics contribute to some of the health inequalities. The participants were 7340 (5122 men and 2218 women) British employees, 2297 (1638 men and 659 women) Japanese employees, and 8164 (1649 men and 6515 women) Finnish employees. All the participants were civil servants aged 40–60 years. Both male and female low grade employees had poor physical functioning in all cohorts. British and Japanese male low grade employees tended to have poor mental functioning but the associations were significant only for Japanese men. No consistent employment-grade differences in mental functioning were observed among British and Japanese women. Among Finnish men and women, high grade employees had poor mental functioning. In all cohorts, high grade employees had high control, high demands and long work hours. The grade differences in poor physical functioning and disadvantaged work characteristics among non-manual workers were somewhat smaller in the Finnish cohort than in the British and Japanese cohorts. Low control, high demands, and both short and long work hours were associated with poor functioning. When work characteristics were adjusted for, the socioeconomic differences in poor functioning were mildly attenuated in men, but the differences increased slightly in women. This study reconfirms the generally observed pattern of socioeconomic inequalities in health for physical functioning but not for mental functioning. The role of work characteristics in the relationship between socioeconomic status and health differed between men and women but was modest overall. We suggest that these differences in the pattern and magnitude of grade differences in work characteristics and health among the 3 cohorts may be attributable to the different welfare regimes among the 3 countries.  相似文献   
25.

Objective

To investigate the effects of lifestyle factors on overweight among Japanese adolescents.

Methods

We studied 5753 junior high school students (2842 boys and 2911 girls) aged 12 to 13 years. The students were residents of Toyama prefecture, Japan and completed a questionnaire about their height, weight, and lifestyle factors, in June and July 2002. Subjects with a body-mass index (BMI) higher than age- and sex-specific cut-off points were defined as obese. Parental overweight was defined as a BMI of 25 or higher. Logistic regression analysis was used to examine associations between lifestyle factors and overweight.

Results

Skipping breakfast, eating quickly, excessive eating, physical inactivity, and long hours of TV watching were positively and significantly associated with overweight in both sexes. There was a negative association between snacking and overweight in girls (P < 0.001); no such association was found in boys (P > 0.05). Nighttime snacking was negatively associated with overweight in boys and girls (P < 0.05). Extended video game playing (≥2 hours; OR = 2.00, P = 0.012) and short sleep duration (<7 hours; OR = 1.81, P = 0.004) were significantly associated with overweight in girls only. The respective risks of overweight that derived from the subjects’ fathers and mothers were 2.0 and 2.5 times, respectively, in boys and 1.9 and 3.0 times in girls.

Conclusions

Parental overweight, skipping breakfast, eating quickly, excessive eating, long hours of TV watching, long hours of video game playing, physical inactivity, and short sleep duration were associated with adolescent overweight. Furthermore, there were significant negative associations between adolescent overweight and snacking in girls and nighttime snacking in both sexes.Key words: overweight, lifestyle factors, adolescents, Japan, Toyama birth cohort study  相似文献   
26.
Purpose  It is known that a moderate to large volume of alcohol produces deterioration in obstructive sleep apnea (OSA), however, no consensus has been achieved with respect to the influence of a moderate volume of alcohol on mild to moderate OSA. In this study, we investigated the influence of alcohol on OSA-associated parameters in healthy middle-aged males drinking a moderate volume of alcohol (<1 g alcohol/kg bodyweight per day). Methods  Subjects were 23 healthy males (mean age of 46.0) with a habitual ingestion of moderate a mounts of alcohol. Respiratory sleep parameters were measured through the fitting of an Apnomonitor III (Chest Inc.) and portable sleep monitoring device (Actiwatch: AMI Inc.) to subjects on three nights; an alcohol-free night, a night on which they drank alcohol with dinner, and a night on which they drank alcohol within 30 minutes before retiring to bed. The measurements were categorized into the early and late halves of assumed sleep for analysis. Results  The apnea-hypopnea index was significantly higher when drinking alcohol before retiring [mean (SD): 7.8 (8.2) events/hour] than the values on the alcohol-free day [2.9 (4.5) events/hour] and when drinking alcohol with dinner [3.8 (5.3) events/hour]. Furthermore, drinking alcohol before retiring resulted in lower arterial blood oxygen saturation (SpO2) during the early half of sleep [94.8 (1.4) %] when compared to the values on the alcohol-free day [95.7 (1.3) %] and drinking alcohol with dinner [95.4 (1.6) %]. In addition, the percentage of time with SpO2<92% (hypoxic event) during the early half of sleep [4.9 (9.3) %] was significantly higher than the values on the alcohol-free day [1.2 (1.8) %] and when drinking alcohol with dinner [1.4 (1.8) %]. Conclusion  These results suggest that moderate ingestion of alcohol within 30 minutes before retiring aggravates OSA-associated parameters in healthy males.  相似文献   
27.
Using a middle cerebral artery occlusion model in adult cats, we investigated the ischemic time threshold for inflicting damage on cerebral vessel behavior and brain tissue. With the transorbital approach, a middle cerebral artery (MCA) was exposed and temporarily obstructed by a Zen's clip. Animals were divided into ten groups (each group: N = 8) according to the ischemic time of 10, 20, 30 minutes, 1, 2, 4, 6, 8, 12, 24 hours. Five hours after the recanalization, Evans' blue dye was injected intravenously and after further 30 minutes, the brain was fixed with transaortal perfusion for histological examinations. A cranial window was made above the ectosylvian gyrus which has poor anastomosis. The pial vessel behavior was observed through the cranial window and evaluated using an intravital microscope and a videoangiometer. Considering the correlation between functional change of vessel behavior and pathological change in the brain, the threshold time of ischemia inflicting irreversible damage was estimated. In the 30 minute ischemia group, deterioration of vessel behavior began to be observed as well as extravasation of Evans' blue dye. As the ischemic duration became longer, infarction and hemorrhage, which showed close correlation, increased. When the duration of ischemia was 6 hours, the infarcted area was significantly larger than that of the 4-hour ischemia group. Intracranial pressure (ICP) markedly increased as soon as recanalization took place. We think this phenomenon is due mainly to swelling. About three hours after recanalization, ICP further increased due to severe vasogenic edema in addition to the brain swelling.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
28.
Chemosensitivity assays including colony forming assay (CFA), MTT dye reduction assay (MTT assay) and thymidine incorporation assay (TIA) for cultured rat and human glioma cells were conducted to determine the correlation among them and the in vivo antitumor efficacy of anticancer drugs using rats implanted glioma cells. Cytotoxicity of various agents such as ACNU, ACR, CDDP, VCR or BLM, was estimated from the concentrations which caused 50% inhibition of the cell growth at the peak plasma concentration. The survival time of tumor bearing rats was assessed after ip treatment with these agents at their estimated clinical doses. This parameter was greater in the drugs that were shown to be highly sensitive in CFA and was consistent with the data for CFA. In the chemosensitivity assays, CFA closely correlated to MTT assay for all agents except VCR, but poorly so to TIA. The results in this study indicate that MTT assay seemed to be useful for determining the chemosensitivity of anticancer drugs and that chemosensitivity assay should be conducted depending on the nature of anticancer drug.  相似文献   
29.
Hypogonadism in male hemodialysis patients has been previously reported. However, its precise pathogenesis has not yet been clarified. Mepitiostane and nandrolone decanoate are anabolic steroids prescribed for uremic anemia, and those may possibly exacerbate uremic gonadal damage. We studied the influences of these steroids on male gonadal function. Seventy-six hemodialysis patients were selected and examined for levels of luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone, and prolactin. Twenty-three patients who received anabolic steroids showed lower testosterone values (205.2 +/- 35.6 ng/dl) than did patients without these steroids (449.7 +/- 21.3 ng/dl). Gonadotropins and prolactin showed no significant differences between the patients with and without the steroids. The testosterone values of three patients with mepitiostane increased after they stopped taking steroids. One patient suffering from complete aspermia recovered (sperm count: 0/ml to 1300 x 10(4)/ml) after discontinuation of mepitiostane and administration of human chorionic gonadotropin (HCG). This clinical study suggests that some anabolic steroids play a role in uremic hypogonadism; thus mepitiostane or its analogues should be carefully prescribed for young male patients.  相似文献   
30.
Some of our earlier reports have dealt with experiments on the central caudal arteries of a series of anesthetized rats. The results of these experiments were expressed by a relationship derived from the Windkessel theory where f(t) = alpha dz(t)/dt + beta z(t). When this theory is used, the measured blood flow forms f(t) and calculated wave forms alpha dz(t)/dt + beta z(t) agree closely. In these studies, we discovered that, when blood flow adz(t)/dt + beta z(t) agree closely. In these studies, we discovered that, when blood flow decreases, CR (time constant tau, the product of the blood vessel compliance C and the peripheral resistance R) values increase and vary widely. In the present study, 1) we investigated changes in CR when blood flow increases, and, 2) the method of least squares was used in calculating the formula given above. We achieved a better conformity between measured blood flow and calculated blood flow and perceived a clearer relationship between mean blood flow and CR than when they were calculated by the old method.  相似文献   
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