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排序方式: 共有770条查询结果,搜索用时 19 毫秒
1.
A clinical trial on the prevention of catheter-related sepsis using a new hub model. 总被引:8,自引:0,他引:8
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M Segura F Alvarez-Lerma J M Tellado J Jiménez-Ferreres L Oms J Rello T Baró R Sánchez A Morera D Mariscal J Marrugat A Sitges-Serra 《Annals of surgery》1996,223(4):363-369
BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks. 相似文献
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Epidermal growth factor directly stimulates steroidogenesis in primary cultures of porcine Leydig cells: actions and sites of action 总被引:7,自引:0,他引:7
The actions and the mechanisms of action of epidermal growth factor (EGF) in testicular steroidogenesis were investigated using a model of primary culture of purified porcine Leydig cells from immature intact animals. EGF decreased (1.7-fold) human CG (hCG)-induced dehydroepiandrosterone (DHEA) accumulation in the medium whereas it enhanced (2.5-fold) that of testosterone. The maximal and half-maximal effects on both DHEA and testosterone secretions were observed at similar concentrations which were, respectively, 3 (5 x 10(-10) M) and 0.7 (11 x 10(-11) M) ng/ml EGF, after 72-h treatment. EGF effect on DHEA and testosterone secretion was similarly observed whether the cells were acutely (3 h) stimulated with hCG (1 ng/ml) or with 8-bromo-cAMP (10(-3) M). To further localize the steroidogenic biochemical steps affected by EGF, the growth factor action on steroidogenic enzyme activities was investigated. EGF increased delta 5 steroid intermediate (i.e. pregnenolone and DHEA) formation [evaluated in the presence of 10(-5) M of WIN 24540, an inhibitor of 3 beta-hydroxysteroid dehydrogenase/iosomerase (3 beta-HSDI) activity]. However, this stimulation was observed in cells when acutely (3 h) stimulated with hCG (0.01-1 ng/ml) but not when incubated with 22R-hydroxycholesterol (0.01-10 micrograms/ml). Such findings indicate that EGF did not affect cholesterol side chain cleavage cytochrome P450 activity but probably increased cholesterol substrate availability for this enzyme in the inner mitochondria. Moreover, EGF significantly (P less than 0.001) increased delta 5 steroid intermediate (i.e. pregnenolone and DHEA) but not delta 4 steroid intermediate (i.e. progesterone and androstenedione) conversion into testosterone, indicating that EGF enhances 3 beta-HSDI activity. Such effects of EGF are directly exerted on Leydig cells since EGF receptors (Kd = 16 x 10(-11) M) are present in primary cultures of purified porcine Leydig cells. Together, the present findings show that in Leydig cells from intact animals, EGF enhances the gonadotropin action on testosterone formation through an increase in the availability of cholesterol substrate in the mitochondria as well as an increase in the activity of 3 beta-HSDI. 相似文献
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全层缝合在预防阑尾炎术后切口感染中的应用 总被引:4,自引:0,他引:4
目的:探讨全层缝合在预防阑尾炎术后切口感染的治疗效果。方法:将皮肤、皮下组织、腹外斜肌腱膜全层褥式缝合(腹膜不予缝合)。结果:56例患者无一例感染,也未发现近期并发症。结论:此方法对预防切口感染有较好疗效,且能缩短手术时间,操作简单,建议值得临床应用。 相似文献
5.
267株烧伤感染细菌的调查分析 总被引:1,自引:0,他引:1
目的:回顾性分析1995年1月至2003年12月间本院烧伤科细菌分布和菌种耐药情况,以指导临床合理用药。方法:收集烧伤病人创面分泌物、血液、痰液及静脉导管末端行普通细菌培养,统计细菌分布情况及常用药物的敏感性。结果:9年来共检出19种267株细菌.其中铜绿假单胞菌和金黄葡萄球菌占83.14%,并有逐渐增加的趋势。铜绿假单胞菌以亚胺培南、头孢哌酮/舒巴坦和多粘菌素B最敏感;氨曲南亦较敏感,且敏感性呈逐渐上升趋势。金黄色葡萄球菌以万古霉素最敏感.呋喃妥因、利福平次之,青霉素类和大部分头孢菌素则高度耐药。结论:目前烧伤感染仍以铜绿假单胞菌和金黄色葡萄球菌为主.防治该两种细菌感染是抗烧伤感染的主要任务。 相似文献
6.
Francisco Robaina Bernardino Clavo Luis Catal Miguel . Carams Jesús Morera 《Neuromodulation》2004,7(1):26-31
The effect of spinal cord stimulation (SCS) on cerebral blood flow (CBF) has, in the past, been evaluated by semiquantitative techniques, but has not been used to treat CBF diseases. The aim of this study was to assess the effect of cervical SCS on regional blood flow by both semiquantitative and quantitative methods. Thirty‐five patients with cervical SCS‐implanted devices were enrolled. The following parameters were measured before and after cervical SCS: systolic and diastolic velocity (cm/s) in the middle cerebral artery (MCA) by transcranial Doppler (TCD) and volume blood flow quantification (ml/min) in the common carotid artery (CCA) by color Doppler. During cervical SCS there was a significant and bilateral increase in systolic (21%) and diastolic (26%) velocity in the MCA and in CCA blood flow (50%). We conclude that cervical SCS increases blood flow in the middle cerebral artery and common carotid artery. The consistent increase supports the potential usefulness of cervical SCS as an adjuvant treatment for cerebral blood flow diseases. 相似文献
7.
F. Deulofeu J. M. Nava F. Bella C. Martí M. A. Morera B. Font D. Fontanals J. Lite J. Garau A. Calderón M. T. Coll S. Uriz V. Pineda 《European journal of clinical microbiology & infectious diseases》1994,13(8):633-638
The incidence and characteristics of invasiveHaemophilus influenzae disease were studied in 43 adult patients admitted to the acute care hospitals in El Vallés County (Barcelona, Spain) between January 1987 and June 1992. The annual incidence ofHaemophilus influenzae disease was 1.2 per 100,000 inhabitants. Pneumonia occurred in 24 patients, meningitis in five, intraabdominal infections in three, obstetric infections in two, epiglottitis in two and cellulitis in one. In six patients the source of infection was unknown. Ten (23 %) of the infections were hospital acquired. Underlying conditions were diagnosed in 30 (70 %) patients. NontypeableHaemophilus influenzae strains predominated in all adult age groups. Sixty-one percent of type b and 34 % of nontypeable strains were ampicillin resistant (p=0.08). Multiple antibiotic resistance was also high among type b (53 %) and nontypeable (18 %) strains. The mortality rate was significantly higher in patients with pneumonia, bactaeremia from an unidentified focus or shock at presentation. 相似文献
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Astrid LA. Kuijpers Rolph Pfundt Patrick LJM Zeeuwen Henri OF. Molhuizen Edwin CM. Mariman Peter CM. van de Kerkhof Joost Schalkwijk 《Clinical genetics》1998,54(1):96-101
Psoriasis is a multifactorial skin disease characterised by epidermal abnormalities and infiltration by lymphocytes and polymorphonuclear leukocytes (PMN). Skin-derived antileukoproteinase (SKALP), also known as elafin, is a potent inhibitor of human leukocyte elastase and proteinase 3, two PMN-derived proteinases implicated in tissue destruction and leukocyte migration. We have shown that, at least at the protein level, SKALP is significantly decreased in lesional skin of patients with pustular psoriasis compared with plaque-type psoriasis. This finding raised the possibility that SKALP could be one of the candidate genes for pustular forms of psoriasis. We therefore performed single strand conformation polymorphism (SSCP) analysis on the SKALP gene to screen for mutations/polymorphisms in the exons of 30 patients with plaque-type psoriasis, 15 patients with pustular psoriasis and 48 healthy controls. In exon 1 a polymorphism was detected at position + 43 relative to the translation start site, resulting in a substitution of threonine for alanine in the signal peptide. In the promoter region a dinucleotide repeat polymorphism was identified. Both polymorphisms were not associated with pustular psoriasis, or psoriasis in general. Our data indicate that the decrease in SKALP activity in pustular psoriasis is not caused by mutations in the coding region of the gene, and that there is no allelic association between pustular psoriasis and SKALP gene polymorphisms. 相似文献