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91.
Toh S  Harata S  Tsubo K  Inoue S  Narita S 《Journal of reconstructive microsurgery》2001,17(7):497-508; discussion 509
The present study compares a recent approach for congenital pseudarthrosis of the tibia, combining a free vascularized fibula graft and an Ilizarov external fixator. Between 1984 and 1993, seven vascularized fibula grafts were performed. In the first six cases, casts or unilateral external fixators were applied, and five of these cases were complicated by fractures of the graft, necessitating secondary procedures or long-term immobilization. The mean follow-up was 12.1 years. Five patients can now walk unassisted, and one uses a brace only outdoors. On average, a brace was required for 18 months. In the recent Ilizarov external fixator case, the fixator was removed after 4 months and a brace was unnecessary at 10 months. There was no leg-length discrepancy, severe ankle deformity, or fracture of the grafted fibula 7 years postoperatively. Combining a free vascularized fibula graft with an Ilizarov external fixator is recommended for this condition.  相似文献   
92.
The tiny nerve terminals of central synapses contain far fewer vesicles than preparations commonly used for analysis of neurosecretion. Photoconversion of vesicles rendered fluorescent with the dye FM1-43 directly identified vesicles capable of engaging in exo-endocytotic recycling following stimulated Ca(2+) entry. This recycling pool typically contained 30-45 vesicles, only a minority fraction (15-20% on average) of the total vesicle population. The smallness of the recycling pool would severely constrain rates of quantal neurotransmission if classical pathways were solely responsible for vesicle recycling. Fortunately, vesicles can undergo rapid retrieval and reuse in addition to conventional slow recycling, to the benefit of synaptic information flow and neuronal signaling.  相似文献   
93.
Exo-endocytotic turnover of synaptic vesicles (SVs) at synapses between hippocampal neurons in culture was examined by electron microscopy (EM). We carried out photoconversion (PC) of the fluorescent endocytotic marker FM 1-43 by using 3,3'-diaminobenzidine to convert the dye signal into an electron-dense product. Electron-dense products were located almost exclusively in SVs, whose densities were bimodally distributed in two sharply demarcated populations, PC-positive (PC+) and PC-negative (PC-). The median densities of these populations did not vary with the proportion of vesicles stained within a presynaptic terminal (bouton). The proportion of PC+ SVs remained constant across consecutive thin sections of single boutons, but varied greatly from one bouton to another, indicating marked heterogeneity in exo-endocytotic activity. Our experiments indicated that only a minority of SVs were stained in most boutons after stimuli known to cause complete turnover of the functional vesicular pool. A direct spatial correlation was found between FM 1-43 fluorescent spots seen with light microscopy and PC+ boutons by EM. The correlation was clearer in isolated boutons than in clusters of boutons. Photoconversion in combination with FM dyes allows clarification of important aspects of vesicular traffic in central nervous system nerve terminals.  相似文献   
94.
A multi-center open study using the internet was performed during the influenza season of 2001-2002 to evaluate the effectiveness of the anti-influenza agent, oseltamivir, on influenza in relation to: (1) age of patients; (2) type of influenza virus; and (3) timing of initial administration after the onset of the first symptoms of influenza. The study comprised of 779 cases of influenza confirmed by rapid detection tests from 44 clinics in Japan. Patients consisted of 4 age groups, 0-6, 7-15, 16-64 and 65-85 years. All patients were administered oseltamivir within 24 hours, at 25-48 or after 48 hours from the onset of the first symptoms of influenza. Data collected from each age group were the highest body temperature and duration of fever (> or = 37.5 degrees C). The percentage of afebrile patients was calculated at 24, 48 and 72 hours after the initial administration; data were also evaluated by the type of influenza virus A and B. The highest body temperature was higher with statistical significance as patients' age decreased. The duration of febrile period (days) was significantly longer in 0-6 years (2.57 +/- 0.95) than in 65-85 years (2.18 +/- 0.93). Evaluation of the percentage of afebrile patients revealed: the percentage at 24 hours was significantly lower in 0-6 years (28.4%) than in 16-64 years (44.0%); the percentage at 48 and 72 hours showed similar results in each age group; the percentage at 48 and 72 hours was significantly higher when administered initially within 24 hours than over 48 hours after the onset of the first symptoms of influenza; the percentage at 24 and 48 hours was significantly higher when administered within 24 hours than at 25-48 hours; and the type of influenza virus did not affect the percentage. In conclusion, effectiveness of oseltamivir seemed to be affected to an extent by the patients' age and little by the type of influenza virus. Oseltamivir was more effective when administered as early as possible after the onset of the symptoms of influenza.  相似文献   
95.
To investigate the relationship between hepatitis B virus (HBV) replication and chronic liver disease, age-specific prevalences of HBeAg, anti-HBe, and HBV DNA polymerase (DNAP) activity were studied in 295 asymptomatic HBV carriers and 183 patients with B-type chronic liver diseases. DNAP activity decreased with age, and there was no difference in the overall prevalence of DNAP activity between the asymptomatic carriers (27.8%) and the chronic liver disease patients (27.3%). The prevalence of DNAP activity in the 40-and-over age group was significantly higher for the chronic liver disease patients (17.5%) than for the asymptomatic carriers (1.7%). The prevalence of HBeAg in the 40- and-over age group was also significantly higher for the chronic liver disease patients (33.8%) than for the asymptomatic carriers (2.6%). These data suggest that viral replication decreased with age and that viral replication occurring in older persons closely related to chronic liver disease.  相似文献   
96.
AIMS: We assessed the effects of cardiac re-synchronization therapy (CRT) in patients who developed otherwise unexplained heart failure (HF) during right ventricular apical (RVA)-pacing for acquired complete atrioventricular block (CAVB). METHODS AND RESULTS: Eighteen consecutive CAVB patients with HF during RVA-pacing were assessed with haemodynamic studies immediately and 12 months after CRT-upgrade. Ten patients had idiopathic CAVB and 13 showed normal left ventricular (LV) function at RVA-pacemaker implantation. HF developed after 81 +/- 10 months. RVA-pacing duration correlated (r = 0.49, P < 0.05) with LV ejection fraction (LVEF) deterioration. Biventricular- (BiV) and LV-pacing acutely improved the systolic function comparably, but only BiV improved diastolic function. One-year post-CRT-initiation, New York Heart Association classification improved 35 +/- 3% (P < 0.05) and the number of hospitalizations decreased 85 +/- 3% (P < 0.0001). CRT decreased LV end-diastolic diameter (LVEDd) 7 +/- 2% (P < 0.01) and increased LVEF by 23 +/- 7% (P < 0.01). The CRT-induced reduction in LVEDd tended to be greater in patients with RVA-pacing for < 5 years vs. > 5 years (7.7 +/- 2.5 vs. 3.6 +/- 1.0 mm, P = 0.08). CONCLUSION: CRT-upgrade improves the cardiac function and symptoms in CAVB patients with HF progression related to RVA-pacing. Because adverse LV-remodelling may be partly irreversible, consideration should be given to BiV- and LV-pacing upgrade as soon as possible after the indications appear, and prospective studies of the optimal timing of CRT-upgrade may be useful.  相似文献   
97.
To determine the prevalence and severity of carotid artery lesions and which risk factors might be responsible for atherosclerosis in end-stage renal disease (ESRD) patients, we tested for carotid atherosclerosis (CA) by ultrasonography and compared the CA prevalence with well-known or suspected atherosclerotic risk factors in 226 hemodialysis (HD) patients and 2410 healthy residents of Japan. The CA prevalence was higher in the HD patients than in the healthy residents. Univariate analysis showed that HD patients with CA had a higher frequency of diabetes mellitus and left ventricular hypertrophy, and were significantly older, had significantly higher systolic blood pressure and pulse pressure, and lower albumin levels than those without. Multivariate analysis showed that age, pulse pressure, phosphorus, duration of HD, and diabetes mellitus were independent, significant predictors for CA in the HD patients. Neither Chlamydia pneumoniae seropositivity nor elevated homocysteine level was independently, significantly associated with CA. Our results suggest that HD patients had more advanced CA than the healthy residents. CA in the HD patients may be associated not only with several conventional risk factors but also with non-conventional risk factors such as phosphorus and the HD procedure itself.  相似文献   
98.
A 24-year-old Japanese woman was admitted to our hospital in January 2000 with daily diarrhea, abdominal distention, and abdominal pain. Raynaud's phenomenon with erythroderma desquamativum eruptions had been found in 1992. In 1999, small intestinal transillumination showed dilation of the second and third portion of the duodenum. She was diagnosed as amyopathic dermatomyositis because of Gottron's sign despite not having symptoms of myositis, normal serum CPK levels and no histological abnormality by muscle biopsy. In addition, the patient was diagnosed as systemic sclerosis sine scleroderma because Raynaud's phenomenon, leukoma and gastrointestinal dilation were present. Also, antinuclear antibody and anti centromere antibody were positive and anti Scl-70 antibody was dull-positive, despite the absence of scleroderma, extreme edema, and bone resorption. Careful, long term observation will be required because of the splanchnopathy in youth and the complications of systemic sclerosis.  相似文献   
99.
Objective: The prevailing route of hepatitis C virus (HCV) transmission in Japan is unclear, so we expected that a survey of routes of HCV infection in an endemic area might clarify the mode of transmission. Methods: We screened 2049 inhabitants in an isolated rural village of Fukuoka, Japan using HCV markers. All serum samples were assayed for antibody to HCV (anti-HCV) (ELISA), and anti-HCV-positive samples were assayed for HCV RNA and genotype (polymerase chain reaction). Results: The prevalence of anti-HCV was 19.7% and increased with advancing age, from zero in the under 19 yr of age group to 30.7% in the 60–69 yr of age group. HCV RNA was detected in 82.9% of the anti-HCV-positive inhabitants, and 88.3% of them had genotype II. Anti-HCV was detected in 17.8% of the children of HCV-carrier mothers, similar to the rate (15.4%) for all inhabitants in the 40–49 yr of age group, the same age group for the mean age of the anti-HCV-positive children. Anti-HCV was detected in 34.8% of husbands of female HCV carriers and in 22.2% of wives of mate HCV carriers, similar to the rates (36.2% in males and 26.6% in females) for all inhabitants in 60–69 yr of age group, the same age group for the mean ages of carriers' spouses. The prevalence of anti-HCV was the highest in inhabitants of one of three distinct areas of this village where patients had often been injected with insufficiently sterilized syringes and needles for treatment in the same clinic. Conclusion: These observations suggest that medical intervention probably played a more important role in the spread of the HCV infection in the village studied than did familial transmission.  相似文献   
100.
Seven patients with selective IgM deficiency (SIgMD) were studied for cell surface immunoglobulin (SmIg), T-cell subpopulations, and immunoglobulin (Ig) synthesisin vitro by peripheral blood lymphocytes (PBL). Serum IgM levels were less than 25 mg/dl, while IgA, IgG, and IgD were within normal levels. The patients had respiratory or urinary tract infections and two were diagnosed as having systemic lupus erythematosus (SLE). T/B-cell ratios in PBL were within normal ranges. Percentage ratios of B cells bearing SmIg were normal in five patients and decreased in two; however, normal values were seen after 7 days of culture in the presence of PWM. OKT4/OKT8 ratios decreased in five of seven patients, in whom two were due to a decrease in OKT4 and two to an increase in OKT8 cells. One showed a decrease in OKT4 and an increase in OKT8. Analysis of lymphocyte function for Ig synthesisin vitro, using a coculture of counterpart T and B cells from healthy individuals and patients with SIgMD, revealed that the increased function of IgM isospecific suppressor T cells (Ts) was responsible for the IgM deficiency in all seven patients.  相似文献   
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