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91.
目的 探究耐亚胺培南铜绿假单胞菌(IRPA)的oprD2基因缺失在天津地区3所三甲医院内的分布以及该菌的克隆流行情况.方法 采用聚合酶链反应(PCR)方法检测60株IRPA的oprD2基因缺失情况,并以基于肠杆菌科基因间重复一致序列PCR(ERIC-PCR)方法对其中的54株进行分子生物学分型.结果 60株IRPA中有38株oprD2基因缺失.且3所医院的oprD2基因缺失率差异无统计学意义(P>0.05),54株IRPA用ERICPCR方法分为30型.结论 IRPA的oprD2基因缺失在天津地区的分布差异无统计学意义,且提示尚有其他原因造成亚胺堵南/西司他丁耐药株流行;个别科室内的IRPA存在克隆流行趋势,应注意监控IRPA在医院内的暴发流行. 相似文献
92.
Resistance of Copenhagen rats to chemical induction of glutathione S- transferase 7-7-positive liver foci 总被引:2,自引:0,他引:2
Copenhagen (Cop) rats are completely resistant to the chemical induction of
mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis
is virtually unknown. Rat liver is a well- characterized and easily
manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats
are resistant to hepatocarcinogenesis, studies into resistance mechanisms
may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated
using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds
partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60
mg/kg, i.p.). The rats were then promoted using a modified resistant
hepatocyte (RH) protocol (a combination of four doses of 2-
acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a
selective mitotic stimulus for initiated cells). Six weeks after initiation
the rats were killed and liver sections were stained for glutathione
S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic
hepatocytes. Cop rats were found to be highly resistant, having a
approximately 9- and approximately 27-fold smaller percentage of liver area
occupied by GST 7-7-positive foci than susceptible F344 rats following
initiation by DEN and MNU respectively. Furthermore, gross liver nodules
did not form in any of the Cop rats, whereas all F344 rat livers contained
nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during
promotion is necessary to stimulate compensatory hepatocyte division. We
demonstrated that these agents do indeed increase serum transaminase levels
and produce histologic evidence of necrosis in Cop rats. In order for liver
foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes
must be mito-inhibited by 2-AAF. We found that the degree of
mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344
rats. These results show that the Cop rat is highly resistant to the
chemical induction of putative preneoplastic liver foci and nodules.
相似文献
93.
94.
Italian multicentre study on very low-birth-weight babies. Neonatal mortality and two-year outcome 总被引:1,自引:0,他引:1
U de Vonderweid A Spagnolo C Corchia V Chiandotto S Chiappe F Chiappe P Colarizi TDe Luca M Didato MC Fertz F Macagno G Mansi R Paludetto A Priolisi A Spinelli P Zaramella C Zorzi 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(4):391-396
The Italian multicentre study on very low-birth-weight babies is the first collaborative project in Italy on the health status of newborns weighing 500–1499 g at birth: 634 such babies were admitted in 1987–88 to eight Italian NICUs; 424 infants survived and were followed until two years of age, corrected for prematurity. Logistic regression analysis of pre-admission risk factors of in-hospital mortality identified eight statistically significant variables: birth weight, gestational age, sex, antepartum steroids, I-min Apgar score and, on admission to the NICU, body temperature, pH and absence of spontaneous respiration. Using the equation derived from the logistic model, a theoretical mortality rate was calculated for each centre, predicted on the basis of the local incidence of preadmission risk factors. In no case was the predicted mortality significantly different from the observed one. At two years of age, 8 children were blind and 48 had motor disability. Of these, 46 had cerebral palsy: based on a functional evaluation score 14 had severe (degree 4), 20 intermediate (degree 3) and 12 mild cerebral palsy (degree 2). Among 25 variables entered in a logistic regression as risk factors for cerebral palsy, only periventricular leucomalacia and acidosis were significantly associated with the outcome. 相似文献
95.
96.
Allan C. Harrington MD Jason M. Cheyney MPAS PA-C LT BSC USAF Tina Kinsley-Scott MD CAPT MSC USAF Robert J. Willard MD MAJ MC USA 《Dermatologic surgery》2004,30(7):1065-1067
Background. Surgery of the digit is facilitated with adequate hemostasis for visualization of the operative field. Several types of tourniquets have been used for this purpose, including glove fingers, Penrose drains, Marmed digital tourniquets, and standard pneumatic tourniquets.
Objective. To present a novel method to achieve hemostasis during surgery of the digit.
Materials. A slightly oversized sterile glove, a hemostat, and a pair of scissors.
Conclusion. We present a novel method to achieve hemostasis using a sterile glove and a hemostat, that allows the surgeon to methodically titrate the amount of compression necessary to attain a bloodless field while minimizing the risks of excessive pressures.
Surgery of the digit is facilitated with adequate hemostasis for visualization of the operative field. Several types of tourniquets have been used for this purpose, including glove fingers, Penrose drains, Marmed digital tourniquets, and standard pneumatic tourniquets. We present a novel method to achieve hemostasis using a sterile glove and a hemostat that allows the surgeon to methodically titrate the amount of compression necessary to attain a bloodless field while minimizing the risks of excessive pressures. 相似文献
Objective. To present a novel method to achieve hemostasis during surgery of the digit.
Materials. A slightly oversized sterile glove, a hemostat, and a pair of scissors.
Conclusion. We present a novel method to achieve hemostasis using a sterile glove and a hemostat, that allows the surgeon to methodically titrate the amount of compression necessary to attain a bloodless field while minimizing the risks of excessive pressures.
Surgery of the digit is facilitated with adequate hemostasis for visualization of the operative field. Several types of tourniquets have been used for this purpose, including glove fingers, Penrose drains, Marmed digital tourniquets, and standard pneumatic tourniquets. We present a novel method to achieve hemostasis using a sterile glove and a hemostat that allows the surgeon to methodically titrate the amount of compression necessary to attain a bloodless field while minimizing the risks of excessive pressures. 相似文献
97.
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100.
O Livi P L Ferrarini I Tonetti F Smaldone G Zefola 《Il Farmaco; edizione scientifica》1979,34(3):217-228
The preparation of three series of 1,2,3-triazol derivatives, with a naphthalene, quinoline or pyridine ring in 1 position, is described. Preliminary pharmacological screening of some of these compounds showed no appreciable activity. 相似文献