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991.
Colchicine is used for the treatment of various diseases including gouty arthritis, familial Mediterranean fever (FMF) and Behcet's disease. As a modulator of the microtubules at the cytoskeleton level, it arrests cell division at metaphase and inhibits microtubular- dependent cell motility. Controversy exists as to the adverse effect of colchicine on sperm production and function in healthy subjects as well as in gout, FMF and Behcet's patients. Sperm analysis shows a spectrum of pathology, from oligo- and azoospermia to normospermia with disturbances in sperm motility. These inconsistent sperm pathologies can be explained in part by the variability of the pathophysiology of the underlying disease. Thus, it seems that colchicine by itself may not have a significant direct adverse effect on sperm production and function.   相似文献   
992.
Duchenne and Becker muscular dystrophies are among the most severe and frequent inherited disorders. Being still incurable, medical treatment is concentrated on the carrier diagnosis of the members of the affected families. Here we report the results of the studies of 151 members of 41 Hungarian families, obtained with multiplex PCR amplification of 18 exons as well as the muscle specific promoter region, and haplotype analysis of two polymorphic (CA)n repeat microsatellite loci in introns 45 and 49 of the dystrophin gene. The analysis of 15 deletion-type families revealed a frequency of new mutations not differing significantly from that in the other regions of Europe. We also compared the allele distributions of the two microsatellites in randomly selected normal individuals and affected family members. The allele distribution of STRP45 shows interesting differences between the two populations.  相似文献   
993.
OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems. (Am J Obstet Gynecol 1998;178:1222-8.)  相似文献   
994.
Abstract Caries experience and enamel fluorosis prevalence in 8-year-old children belonging to different socio-economic classes were determined in two Chilean twin cities that are served by optimally fluoridated community water from the same waterworks facility. Low socio-economic status (LSES) children had a higher mean dm ft and DMFT indices (P<0.001) than high socioeconomic status (HSES) children. Prevalence of enamel fluorosis in the permanent teeth of LSES children was 0.79, significantly higher (X2= 9.0; P<0.003) than the value 0.59 found in HSES children. The proportion of Dean's scores 2. 3, 4 and 5 in first molars, mandibular and maxillary incisors in LSES children was higher than in HSES children (P<0.001). Differences in prevalence and seventy of enamel fluorosis between both groups are tentatively attributed lo a different pattern of tap water and tea consumption at pre-school ages. Suggestions are advanced to minimize the undesirable prevalence and severity of enamel fluorosis.  相似文献   
995.
996.
Sepsis due to candida infection is a major cause of mortality and morbidity on our unit. Over a period of 3 years and 4 months, 29 cases of candida septicaemia, diagnosed by blood cultures, were encountered at the burn unit at Augusta Regional Medical Center.

Factors known to predispose to fungal sepsis were present in all cases. All patients had large burns (14–98 per cent total body surface (TBSA) with a mean of 48.3 per cent). All but one patient had at least one central venous line. Respiratory problems requiring ventilator support were present in 24 patients.

Sixteen patients had Candida albicans sepsis, two in association with another fungal sepsis. Candida parapsilosis was encountered in nine patients, one in combination with another species. Four patients had Candida tropicalis.

Amphotericin B was prescribed therapeutically in 25 patients, in seven together with fluconazole. Two patients received fluconazole only and two received no antifungal therapy.

There were eight deaths all attributed to sepsis and all of whom had multiple organ failure. Five of those who died had completed a course of amphotericin B therapy, two were receiving treatment at the time of death, and one patient died before culture data became available. Early and aggressive therapy is advised and amphotericin B appears to be the drug of choice.  相似文献   

997.
Three dimensional (3D) phase contrast angiograms contain velocity data, which is discarded after the reconstruction of the projections. In extension to earlier work on velocity quantification with ungated 2D phase data, this paper shows that a useful estimate of the average velocity and flow rate can be extracted from ungated 3D phase contrast angiograms. Simulations and experiments in a phantom and in vivo were performed. For pulsatile flow and strong spin saturation, an over-estimation of the flow rate at the net in-flow end of the imaging volume and underestimation at the net out-flow end was observed. Imaging at lower RF tip angles yielded flow rates close to the correct value within the entire imaging volume. In contrast to ungated 2D experiments, the flow rates determined by repeated 3D experiments showed no variation.  相似文献   
998.
999.
1000.
A variety of substances have been used at laminectomy sites to prevent postoperative epidural scarring. Free grafts of autologous subcutaneous fat are commonly used both clinically and experimentally. The free fat grafts usually survive, but decrease in size by about 50%. Postoperatively, subcutaneous seroma has been observed with the use of fat grafts, as well as recurrent symptoms of neural compression by the graft that required additional operations. When compared to the use of free grafts after laminectomy in dogs, Vicryl mesh produced slightly more scarring, but consistently less than that observed in control animals. The Vicryl mesh was resorbed by a minimal chronic inflammatory response over about 45 days. Seven of 11 fat-grafted zones showed signs of necrosis, at times with a greater collection of inflammatory cells than that associated with the Vicryl mesh. Of the 4 fat-grafted zones that showed good survival, 2 had gross evidence of neural compression. No surgical zone treated with Vicryl mesh exhibited evidence of neural compression. In view of these results, the use of Vicryl mesh at laminectomy sites may be a safer method of limiting postoperative epidural scar formation.  相似文献   
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