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991.
Background and hypothesis: The mechanism of sudden cardiac death occurring in patients with chronic fatigue is controversial. This study was designed to define a hypothesis that coronary arterial spasm and thrombus formation can occur during chronic fatigue. Methods: For evaluating the feasibility of coronary arterial spasm, erythrocyte magnesium (Mg) was measured. Blood coagulability was evaluated by the change of prostaglandin concentration. Subjects included 16 healthy male volunteers (mean age 21.6 ± 2.5 years). Test conditions were as follows: (A) control state: a day following a night of good sleep; (B) temporary sleep deprivation: a day preceded by < 3 h of sleep; (C) chronic sleep deprivation: a day preceded by a month during which sleep lasted < 60% of that in condition (A) above. The erythrocyte Mg concentration was measured by the atomic absorption method. The plasma concentration of thromboxane B2 and 6-keto-prostaglandin F were measured in eight subjects by radioimmunoassay method. Results: (1) Mean erythrocyte Mg concentration was significantly less in chronic sleep deprivation (1.1 ±0.4 mg/dl) than in the control state (1.8 ± 0.4 mg/dl, p<0.01) or in temporary sleep deprivation (1.6 ± 0.4, p<0.01). (2) The level of thromboxane B2 was significantly higher during chronic sleep deprivation than under control conditions (104.4 ± 78.0 vs. 20.4 ± 9.0 pg/ml, p<0.05). (3) There were no significant intergroup differences in 6-keto-prostaglandin F level. Conclusion: These findings could support the hypothesis that coronary arterial spasm and thrombus formation occur in chronic sleep deprivation.  相似文献   
992.
Using Amebocyte lysate of horseshoe crab to measure (1-->3)-beta-D-glucan specifically, a component of the cell wall, several kinds of diagnostic methods for deep mycosis are in practical use in Japan. However, the most important problem is that the judgment of positive or negative is method dependent. To elucidate the cause of the problem, each measurement value of the identical sample by four methods, beta-Glucan Test Maruha (MARUHA), beta-Glucan Test Wako (WAKO). FUNGITEC G Test (FUNGITEC-G) and FUNGITEC G Test MK (FUNGITEC-MK) was compared with the clinical data using 119 cases and 289 tests. Each case was divided into three groups; proven fungal infection, probable fungal infection and non-fungal infection. The negative cases for all the methods tested in the groups of proven fungal infection and probable fungal infection were allergic bronchopulmonary aspergillosis and cryptococcosis, and that for all the methods tested except FUNGITEC-MK method in the group was pulmonary aspergilloma. It seems that these cases cannot be detected correctly by only measuring (1-->3)-beta-D-glucan. On the other hand, the ratio of false positive, positive for non-fungal infection group was high in the case of FUNGITEC-MK. About 23% against the total case was positive for FUNGITEC-MK method, but negative for MARUHA, WAKO, and FUNGITEC-G methods. Although the difference of the sensitivity among four methods was not observed, the specificity, the diagnostic efficiency, and the positive predictive value of FUNGITEC-MK method were remarkably lower than those of the other methods due to false positive measurement. In conclusion, MARUHA, WAKO and FUNGITEC-G except FUNGITEC-MK is not method dependent. It is suggested that FUNGITEC-MK detects non-specific reaction resulted in false positive.  相似文献   
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996.
Parasitological examinations were carried out during July to December, 1989, on 485 inhabitants of four villages in S?o Louren?o da Mata, 25 km northwest of Recife, Pernambuco, Brazil. Approximately 99.6% of the inhabitants were infected with at least one species of intestinal parasites. A high prevalence of Schistosoma mansoni (82.1%), hookworm (80.2%) Trichuris trichiura (69.9%), Ascaris lumbricoides (61.9%) and Entamoeba coli (36.7%) infections were demonstrated. Test tube cultivation revealed that the most common species of hookworm in this region was Necator americanus (88.4%), and also that the prevalence of Strongyloides stercoralis was 5.8%. Three hundred and thirty-four sera were serologically examined for amoebiasis by the gel diffusion precipitation test (GDP) and enzyme-linked immunosorbent assay (ELISA). No positive reaction was observed in all sera as examined by GDP, while 24 sera were positive by ELISA.  相似文献   
997.
Background:   Pressure ulcers are classified as chronic wounds, which do not heal in a timely fashion. Fibronectin is condensed in granulation tissue, and essential glycoprotein of wound healing. It has been proposed that fibronectin degradation may be involved in delaying wound healing. We have investigated whether pressure ulcer fluid (PUF) contains degraded fibronectin. In addition, we tried to identify the proteinase which contributes to fibronectin degradation in PUF.
Methods:   Fibronectin degradation and the presence of neutrophil elastase (NE) in PUF were determined by immunoblot analysis. Fibronectin degradation activity in PUF was determined in the presence of various proteinase inhibitors. NE activity was assessed using NE specific substrate.
Results:   Immunoblot analysis revealed that degraded fibronectin was observed in PUF samples but not in acute wound fluid (AWF). The PUF contained a proteinase capable of degrading freshly added fibronectin and its activity in PUF was blocked by a broad-spectrum serine proteinase inhibitor or sivelestat, a specific neutrophil elastase inhibitor, but not by metalloproteinase and cysteine proteinase inhibitors. Immunoblot analysis of PUF using an antineutrophil elastase antibody revealed that neutrophil elastase was detected as three bands at molecular weights of ∼30 kDa, ∼38 kDa, and ∼54 kDa, indicating that neutrophil elastase in the exudates existed not only as free monomers, but also in polymers or complexes with other molecules.
Conclusion:   These results suggest that PUF contains a high level of neutrophil elastase which may be involved in the delay of the healing of pressure ulcer through the fibronectin degradation.  相似文献   
998.
This study investigated the effects of aerobic exercise training on the early phase of the recovery process following acute myocardial infarction (AMI) in terms of the autonomic nervous system, cardiac function and exercise capacity. Twenty-eight patients in the first week after the onset of AMI were assigned randomly to either a training group or a control group. The training group performed aerobic exercise for 2 weeks. Cardiopulmonary exercise testing was performed 3 times during the 3 months after the onset. Heart rate variability, plasma norepinephrine (NE) levels, and cardiac index (CI) during exercise were measured. In the training group, plasma NE level and deltaCI (peak CI-rest CI) were significantly improved from 1 to 3 weeks after the onset, and the high frequency of heart rate variability and peak oxygen uptake were significantly increased up to 3 months after the onset. In the control group, the plasma NE level and the deltaCI during the 1-3 weeks post-AMI, the high frequency of heart rate variability and the peak oxygen uptake showed a tendency to improve up to 3 months after the onset. These results indicate that sympathetic nervous activity improves soon after the onset of AMI, in conjunction with improvement in cardiac function, and that this improvement is not affected by exercise training. In contrast, the recovery of parasympathetic nervous activity requires a longer period, along with the recovery of exercise capacity, which is facilitated by even short-term aerobic exercise training.  相似文献   
999.
BACKGROUND: The viral load and subtype of hepatitis C virus (HCV) are predictors of the efficacy of interferon (IFN) therapy. The kinetics of HCV during IFN therapy have been described recently, suggesting that HCV infection is highly dynamic. These observations have raised the issue as to whether early monitoring of the viral load can help guide IFN therapy. METHODS: We measured HCV-RNA levels at 0, 24 and 48 h after the start of IFN-alpha treatment (10 MU daily for 2 weeks and then three times weekly for 22 weeks) or IFN-beta treatment (6 MU daily for 6 weeks). Then we analyzed the relationship between HCV kinetics and therapeutic response using stepwise multivariate logistic regression analysis. RESULTS: The exponential decay slope of the viral load during the first 24 h, not the first 48 h or the next 24 h, was a predictor of viral eradication at 6 months after completion of the treatment (sustained response; P = 0.0023). This decay slope was not affected by the HCV serotype or the type of IFN used. Initial viral load and HCV serotype were also predictors, as reported previously (P < 0.0001 and P = 0.0347, respectively). We also proposed a model using a prognostic index that predicted a sustained response with more than 80% sensitivity, specificity and efficacy in an independent and external group of patients. CONCLUSION: This study demonstrated that the exponential decay slope of the viral load during the first 24 h was an important predictor of the response to IFN therapy as well as the initial viral load and HCV serotype. The model may also be useful for the clinical management of IFN therapy.  相似文献   
1000.
Tanabe M  Goto M 《Gerontology》2001,47(2):77-81
BACKGROUND: There is a well-established association between Werner's syndrome (WS) and hyperhyaluronic aciduria; however, to date hyaluronan (HA) in the serum has not been statistically linked with WS. Recently, the gene that causes WS has been defined as a DNA helicase on chromosome 8, and 19 different mutations in WS patients have been identified. It is not known whether the mutation type of the Werner helicase gene affects the levels of serum and urine HA in WS patients. OBJECTIVE: To evaluate the association of serum HA with WS, and the relationship of the serum and urine HA levels to the mutation type. METHODS: HA both in the serum and the urine was measured in 40 patients with WS and 114 normal controls. The serum and urine HA were quantified by sandwich binding protein assay and competitive ELISA-like method, respectively. The muation on WS helicase gene was analyzed by mutant-allele-specific amplification and oligomer ligation assay. Results: WS patients showed significantly higher levels of HA in the serum (mean +/- SD: 115.7 +/- 119.8 ng/ml, p < 0.001) and urine (1,040.8 +/- 777.3 ng/mg creatinine, Cre, p < 0.001) than age-matched controls (serum HA: 15.8 +/- 14.2 ng/ml, urine HA: 379.7 +/- 124.2 ng/mg Cre). The serum and urine HA levels of WS patients are almost equal to those of normal controls over 80 years (serum HA: 118.5 +/- 108.4 ng/ml, urine HA: 914.5 +/- 712.1 ng/mg Cre). There was a significant correlation between serum and urine HA levels in WS patients (r = 0.42, p = 0.007). Analysis of the mutation on the helicase gene in 22 WS patients showed that among 44 chromosomes, 3 (6.8%) chromosomes had type 1 mutation, 22 (50.0%) had type 4 mutation, 14 (31.8%) had type 6 mutation, and the rest had other mutations. The serum and urine levels of HA did not show any significant association with the mutation type. Conclusion: The hyperhyaluronic aciduria in WS reflects the high level of serum HA. The serum and urine HA levels are useful biochemical markers for WS irrespective of the muation type of the Werner helicase gene.  相似文献   
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