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111.
The changes in bladder function occurring after a surgical alteration in bladder outflow resistance were studied in 20 males undergoing transurethral prostatectomy (TURP) and in 20 females undergoing an endoscopic bladder neck suspension (EBNS). Serial cystometrograms (CMG) were performed before operation, and on alternate days after spontaneous micturition was re-established, for 5 days in the males and for 21 days in the females. CMGs were repeated at 3 months and 1 year after operation. After TURP voiding pressures (Pdet) fell rapidly from a mean of 118 cm H2O before operation to 57 cm H2O at 5 days, with an increase in flow rate during this time from 10.5 ml/s to 24 ml/s. Detrusor instability that had been present in 14 patients resolved within 2 days in 12. There was no further significant urodynamic change over the 1-year study period. After EBNS, there was an early rise in voiding pressure (Pdet rose from 26 cm H2O before operation to 42 cm H2O at 3 days). This continued to increase up to 21 days particularly in those patients with initial large residuals. Three patients developed detrusor instability. Flow rates were greatly reduced at first (27 ml/s before operation and 13 ml/s at 3 days), and gradually increased in line with voiding pressures, yet were still diminished 1 year after operation. The urodynamic changes following a reduction in bladder outflow resistance by TURP are immediate and sustained and unlikely to be the result of structural changes within the bladder wall. EBNS produces an increase in outflow resistance and it can be several weeks before balanced voiding is achieved, with significantly increased detrusor pressures needed to achieve complete bladder emptying at a reduced flow rate.  相似文献   
112.
A retrospective case-control study of 50 MRSA-positive patients was carried out during an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) at an acute general hospital in London. Controls were randomly selected from MRSA-negative patients admitted during the outbreak period. Risk factors investigated included length of admission prior to screening, number of ward changes, main diagnosis, extent of staff contact, pressure sores, surgical and other invasive procedures and antibiotic treatment. Outcome variables examined were rates of infection (versus colonization) with MRSA and mortality. Patients with MRSA were in hospital longer before microbiological specimens were taken and moved wards more often than controls. In a logistic regression analysis, length of stay in hospital, pressure sores, physiotherapy and surgical procedures were associated with a significantly increased risk of acquiring MRSA. Odds ratios (and 95% confidence intervals) for having acquired MRSA were: 8·3 (1·02−71·43) if a patient had pressure sores; 3·7 (1·10−12·5) if they received physiotherapy; and 3·2 (1·82−10·0) if they underwent surgical procedures. The rate of clinical infection amongst patients with this strain of MRSA was 26% and included life-threatening infections such as septicaemia, underlining the potential virulence of MRSA. Surgery and physiotherapy may have been markers of debility. Physiotherapy was probably a marker of increased rates of contact with all hospital staff, and high standards of hand hygiene should be promoted amongst all staff as the most important factor in controlling an outbreak of MRSA. Good bed management is essential for hospital infection control.  相似文献   
113.
Hereditary hypertriglyceridemic rats (hHTg) were developed as a new genetic model for the study of relationships between blood pressure (BP) and metabolic abnormalities. This strain has been produced by selective inbreeding from Wistar rats according to the rise of plasma triglycerides induced by a high-sucrose diet. Though hHTg rats display hypertriglyceridemia, impaired glucose tolerrance, hyperinsulinemia, insulin resistance and increased BP even without nutritional stimuli, high sucrose feeding further aggravates these symptoms. High plasma triglycerides levels in hHTg rats seem to be a consequence of their hyperproduction. Impaired insulin action is responsible for the defective glucoregulation in this strain. The loss of insulin responsiveness might be due to a reduction in the number of glucose transporters. Highly significant relationships among plasma triglycerides, ouabain-resistant Na+ transport and BP were demonstrated in the hHTg rats. Segregating populations (F2 hybrids) should be used for genetic analysis of the primary role of lipid and/or ion transport abnormalities in the pathogenesis of this form of genetic hypertension.  相似文献   
114.
Nasal resistance is affected by posture. In this study, the effects of supine and lateral recumbent positions were investigated in eight normal subjects and 31 patients with allergic rhinitis. Of the 31 patients with allergic rhinitis, five showed unilateral complete nasal obstruction and one patient showed bilateral complete obstruction during the change of posture. Total nasal resistance had a tendency to increase with repeating the change of posture (a paired t-test, P < 0.05). The supine and lateral recumbent positions did not induce variable changes in total nasal resistance in normal subjects. Posture induces complete nasal obstruction in the supine or lateral recumbent positions in some patients with allergic rhinitis.  相似文献   
115.
HIV/AIDS合并深部真菌感染的调查与耐药研究   总被引:6,自引:0,他引:6  
目的:了解艾滋病病毒/艾滋病(HIV/AIDS)合并深部真菌感染的临床状况、病原菌分类及耐药现状。方法:总结近年来收治的131例HIV/AIDS患者的临床资料,分析深部真菌感染的发生情况及药敏试验结果。结果:HIV/AIDS患者合并深部真菌感染48例,感染率为36.6%,其中以念珠菌为主,占61%,感染部位以消化道为主,占62.7%。随着CD4^ T淋巴细胞的减少,合并深部真菌感染的感染率逐渐增加。念珠菌对益康唑(ECO)、酮康唑(KET)、咪康唑(MIC)、制霉菌素(NYS)、氟康唑(FLU)、伊曲康唑(ITR)、5-氟胞嘧啶(5-FC)、两性霉素B(AMB)耐药率分别为69.4%、66.7%、58.3%、44.4%、43.8%、36.4%、14.3%、13.9%。结论:HIV/AIDS患者合并深部真菌感染率高,且多有药耐药性,特别是对咪唑类抗真菌药物已呈明显耐药,应引起临床医生的高度警惕。  相似文献   
116.
中国鼠疫菌种资源遗传特征分析   总被引:10,自引:0,他引:10       下载免费PDF全文
目的 建立《中国甲类传染病菌种资源库》,选择适当的指标,以反映中国鼠疫菌种的遗传背景。方法 使用传统的和分子生物学方法,测定中国鼠疫菌种代表菌株的遗传特征。并对遗传特征的分布及其意义进行分析。结果 利用6项指标,将中国的鼠疫菌划分成15种遗传型,每一型占据一片相对独立的而又自相延续的地理空间。分析遗传型之间的亲缘关系,并根据菌株间的差异,追溯鼠疫耶尔森菌作为一个生物种形成后的进化过程。结论 中国各鼠疫自然疫源地存在着不同特征的鼠疫菌株,但为达到对菌株认同的目标,还需要确定更多的遗传指征。  相似文献   
117.
Great advances in neurobiology have resulted from 100 years of neural transplantation research. In the last 20 years, there has been a focus on using neural transplantation to repair the damaged central nervous system (CNS) utilising experimental animal models of various human neurodegenerative disease and CNS injury. Since 1985, there has been a rapid proliferation of adrenal medullary autograft transplantation to the caudate nucleus of humans with Parkinson's disease. However, this operation proved to be unsuccessful and was associated with unacceptable morbidity. Implantation of human fetal mesencephalon into patients with severe parkinsonism has supplanted the adrenal operation and has produced promising results, with some patients reported to improve markedly and some evidence of graft survival noted on positron emission tomography (PET). Host tissue recovery appears to be an important mechanism for this clinical improvement. The optimal technique is to use three to four fetuses from induced abortions of 6.5 to 8 weeks gestation, with multiple stereotactic implants into the putamen and caudate nucleus. Many biological questions still remain and the community remains troubled by the ethical problems of using fetal tissue obtained from abortions. This procedure is still experimental and should be restricted to a few centres with excellence in cell and molecular biology. A multicentre study is needed to more carefully evaluate CNS transplantation. Cloned neural precursor cells or immortalized embryonic cell lines genetically modified to manufacture selected growth factors or neurotransmitters may offer an alternative to the use of human fetal tissue. Much more experimental animal research is necessary before transplantation can be used to treat other CNS maladies.  相似文献   
118.
乌鲁木齐市家蝇抗药性现状及发展趋势分析   总被引:2,自引:0,他引:2  
目的 分析乌鲁木齐市家蝇对化学杀虫剂的抗药性现状及发展趋势,探讨防制对策。方法 常规微量点滴法。结果 对溴氰菊酯的抗性系数在24.00-253.67;对敌敌畏的抗性系数在11.44-53.24;对二氯苯醚菊酯抗性系数在9.29-36.10,对氯氰菊酯的抗性系数在2.32-9.62。结论:8年来家蝇对4种杀虫剂的抗药性在不断上升,仍保持较高水平,但迅速上升的趋势开始减缓。  相似文献   
119.
Adultacuteleukemia (AL)isoneofthemostcommonmalignanttumorsofhematology .Withtherecentprogressinchemotherapyandsupportivether apy ,theremissionandsurvivalrateinALhavebeenmarkedlyimproved .However ,drugresistanceandrelapsearestillimportantfactorsaffectinglongsur vivalofthese patients .Theabnormalregulationofcellcycleisanotherfactorthatcannotbeignoredex ceptformultipledrugresistance (MDR) .WedetectcyclinA ,multidrugresistantgene (mdrl) ,topoiso meraseⅡα(TopⅡα)andbcl 2inadultpatientswithA…  相似文献   
120.
致倦库蚊有机磷抗性相关扩增酯酶B基因的多样性   总被引:5,自引:0,他引:5  
本实验从佛山和成都两地的致倦库蚊群体中筛选出3个酯酶类型不同的有机磷(OP)抗性品系,FS-1、FS-2和CD-1品系。各品系的酯酶基因B扩增水平、酯酶活性和OP抗性水平三者一致。各品系酯酶B基因限制性酶切片段比较分析表明,我国的OP抗生库蚊群体中不仅有世界性分布的酯酶B1和B2,而且在佛山和成都地区各有一个新的独立扩增的酯酶B,分别命名为B6和B7。  相似文献   
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