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排序方式: 共有4109条查询结果,搜索用时 15 毫秒
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Kurt Hannes Wollinsky Margret Oethinger Michaela Bü chele Patrick Kluger Wolfhart Puhl Hans-Hinrich Mehrkens 《Acta orthopaedica》1997,68(3):225-230
40 patients undergoing primary hip arthroplasty, given autologous processed blood transfusion, were randomized to receive no antibiotic prophylaxis (group A, n 20) or cefuroxime (1.5 g single injection; group B, n 20). Bacterial contamination at various steps in the autotransfusion procedure was assessed in liquid and solid culture media. the operation field and the wound drainage blood were never contaminated in either of the groups but some of the suction tips were. Parts of the Vacufix® blood collection bags of group A contained bacteria, but none in group B. Processed red blood cell concentrates in both groups showed bacterial growth. Greater blood loss did not increase the contamination rate in general. Isolated bacteria included the species Staphylococcus epidermidis, coagulase-negative staphylococci and Propionibacteria in both groups, but with different cell counts. in addition, Corynebacterium bovis et minutissimum and Moraxella were identified in group A.
In conclusion, autologous blood transfusion was a safe procedure. If contamination occurred, the bacterial count was low, and the bacteria of low pathogenicity. Antibiotic prophylaxis with cefuroxime reduced this contamination of suction tips and collection bags and limited the transfer of autologous blood products. 相似文献
In conclusion, autologous blood transfusion was a safe procedure. If contamination occurred, the bacterial count was low, and the bacteria of low pathogenicity. Antibiotic prophylaxis with cefuroxime reduced this contamination of suction tips and collection bags and limited the transfer of autologous blood products. 相似文献
3.
A Oxholm M Diamant P Oxholm K Bendtzen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1991,99(1):58-64
The presence of human cytokines was examined in parallel skin biopsies and epidermal single cell preparations obtained from normal individuals. Using biotin-avidin-peroxidase and immunofluorescence techniques and antibodies against recombinant cytokines, a granular intercellular/membrane-associated staining for interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF alpha), but not IL-1 alpha or beta, was observed. An epidermal cytoplasmic staining pattern was also detected, which was most pronounced using the anti-rIL-6 antiserum. In the epidermal single cell preparations, membrane-associated staining was detected for both IL-6 and TNF alpha. Double staining revealed that CD1-positive Langerhans cells (LC) failed to express any of the examined cytokines. In vitro binding of rIL-6 or rTNF alpha to skin sections and epidermal single cell preparations indicated that the cell surface-associated IL-6 and TNF alpha originally demonstrated on keratinocytes were truly membrane-bound. Finally, co-cultivation of epidermal cells with an IL-6 responsive cell line, B9, and testing of epidermal cell supernatants in this assay, indicated that the in vivo membrane-bound IL-6 had biological activity. 相似文献
4.
Tomáš Šimůnek Martin Štěrba Olga Popelová Michaela Adamcová Radomír Hrdina Vladimír Geršl 《Pharmacological reports : PR》2009,61(1):154-171
The risk of cardiotoxicity is the most serious drawback to the clinical usefulness of anthracycline antineoplastic antibiotics, which include doxorubicin (adriamycin), daunorubicin or epirubicin. Nevertheless, these compounds remain among the most widely used anticancer drugs. The molecular pathogenesis of anthracycline cardiotoxicity remains highly controversial, although the oxidative stress-based hypothesis involving intramyocardial production of reactive oxygen species (ROS) has gained the widest acceptance. Anthracyclines may promote the formation of ROS through redox cycling of their aglycones as well as their anthracycline-iron complexes. This proposed mechanism has become particularly popular in light of the high cardioprotective efficacy of dexrazoxane (ICRF-187). The mechanism of action of this drug has been attributed to its hydrolytic transformation into the iron-chelating metabolite ADR-925, which may act by displacing iron from anthracycline-iron complexes or by chelating free or loosely bound cellular iron, thus preventing site-specific iron-catalyzed ROS damage. However, during the last decade, calls for the critical reassessment of this “ROS and iron” hypothesis have emerged. Numerous antioxidants, although efficient in cellular or acute animal experiments, have failed to alleviate anthracycline cardiotoxicity in clinically relevant chronic animal models or clinical trials. In addition, studies with chelators that are stronger and more selective for iron than ADR-925 have also yielded negative or, at best, mixed outcomes. Hence, several lines of evidence suggest that mechanisms other than the traditionally emphasized “ROS and iron” hypothesis are involved in anthracycline-induced cardiotoxicity and that these alternative mechanisms may be better bases for designing approaches to achieve efficient and safe cardioprotection. 相似文献
5.
6.
H S Jensen N Tvede M Diamant H H Mogensen M B Hansen B S Thomsen P B Pedersen K Bendtzen 《Scandinavian journal of rheumatology》1991,20(2):83-90
Synovial fluid (SF) and blood from 24 patients with non-traumatic, sterile hydarthron were examined for monocyte elastolysis (M?E) and for levels of interleukin 6 (IL-6) and of soluble interleukin 2 receptor (sIL-2R). Six patients had osteoarthrosis (OA) and 18 patients had inflammatory hydarthron (IH), 10 of whom had rheumatoid arthritis (RA). Blood M?E was lower in OA than in IH, both measured as basal M?E activity and after in vitro stimulation with immune complexes and phorbol myristate acetate (PMA). SF M?E was higher than M?E in blood (p less than 0.01). This increase in SF M?E could be mimicked in vitro by prestimulation of blood M? with low levels of IC. SF IL-6 and sIL-2R were also elevated (p less than 0.01). All three parameters correlated to the degree of joint inflammation evaluated by SF leucocyte level, complement activation, blood C Reactive Protein, and to the clinical evaluation of the joint. The increase in SF M?E, IL-6 and sIL-2R in patients with IH, points to a stimulation of M? and lymphocytes in the joint. 相似文献
7.
8.
Activation of influenza A viruses by trypsin treatment. 总被引:86,自引:0,他引:86
A comparative analysis has been carried out on the infectivity of virus of several influenza A strains grown in different host systems. Strains A/swine/Shope/31 (Hsw1N1), A/PR/8/34 (HON1), A/FM/1 (H1N1), A/Singapore/1/57 (H2N2), A/equine/Miami/1/63 (Heq2Neq2), and A/chick/Germany/49 (Hav2Neq1) exhibit host-dependent differences in infectivity. Virions grown in embryonated eggs and cultures of chorioallantoic membrane cells are highly infectious, whereas virions grown in cultures of chick embryo cells have a low infectivity that significantly increases after treatment in vitro with trypsin. In contrast, fowl plague viruses do not show host-dependent variations in infectivity. Virions grown in all host systems tested are highly infectious, and the infectivity of virions grown in chick embryo cells cannot be enhanced by trypsin treatment.The activation of virus particles appears to be based on the cleavage of hemagglutinin glycoprotein HA. This concept is supported by the following observations: (i) In virions of low infectivity only uncleaved glycoprotein HA can be detected. Virions of high infectivity exhibit complete or at least partial cleavage of the hemagglutinin. (ii) The activation of virions by trypsin treatment is always paralleled by cleavage of HA. (iii) Cleavage of HA is the only effect which can be detected after trypsin treatment. The neuraminidase is neither inactivated nor removed from the virion. (iv) Studies on recombinants of virus N and fowl plague virus (Rostock) show that host-dependent variation of infectivity and activation by trypsin, features specific for parent virus N, are found only with recombinant N(H)-FPV/Ro(N) but not with recombinant FPV/Ro(H)-N(N).Efficient plaque formation and serial passages are possible only if highly infectious particles are formed in a given host system. Thus, all strains analyzed undergo, in the absence of trypsin, successive growth cycles in eggs and chorioallantoic membrane cells and form plaques in chorioallantoic membrane cells. In contrast, in chick embryo cells only viruses containing the fowl plague virus hemagglutinin produce plaques and replicate under multiple cycle conditions without the addition of trypsin.The data show that cleavage of HA is not a precondition for virus assembly and hemagglutinating activity, but that it is necessary for infectivity. These findings are compatible with the hypothesis that, in addition to its role in adsorption, the hemagglutinin has another function in the infection process and cleavage is required for this function. 相似文献
9.
Kevin P Weinfurt Michaela A Dinan Jennifer S Allsbrook Jo?lle Y Friedman Mark A Hall Kevin A Schulman Jeremy Sugarman 《Academic medicine》2006,81(2):113-118
PURPOSE: To document the current state of institutional review board (IRB) and conflict of interest committee policies regarding disclosures of financial conflicts of interest to potential research participants, and to use this information to identify and share models for effectively achieving disclosure. METHOD: The authors identified the 123 U.S. academic medical centers that have IRBs and sought their IRB and institutional policies regarding financial conflicts of interest. In February and March 2004, using manual and key word searches, each institution's Web site was searched to identify documents containing information regarding the disclosure of financial conflicts of interest. Letters were sent to 24 institutions that had either no information or incomplete information posted on their Web sites. To assess institutions' guidelines for disclosure, the authors extracted and content coded each institution's information on disclosure. RESULTS: Relevant information was obtained from 120 (98%) academic medical centers (AMCs), of which 57 (48%) mentioned disclosing financial conflicts to potential research participants. Of these 57, 33 (58%) included verbatim language that could be used in informed consent documents. AMCs' recommendations and requirements for disclosure included details of the financial arrangement, administrative management of conflicts of interest, and encouragement of dialogue between the investigator and the potential research participant. CONCLUSIONS: Considerable variability exists concerning the specific information that should be disclosed. Most of the AMCs' policies were consistent with the goal of protection from legal liability. Significant questions remain, however, concerning the goals of disclosure and the most effective methods for achieving those goals. 相似文献
10.
Emotional abuse, self-blame, and self-silencing in women with irritable bowel syndrome 总被引:5,自引:0,他引:5
Ali A Toner BB Stuckless N Gallop R Diamant NE Gould MI Vidins EI 《Psychosomatic medicine》2000,62(1):76-82
OBJECTIVE: The purpose of this study was to investigate the presence of emotional abuse and two psychosocial constructs (self-blame and self-silencing) in a sample of women diagnosed with irritable bowel syndrome (IBS) relative to a comparison sample of women diagnosed with inflammatory bowel disease (IBD). METHODS: Women diagnosed with IBS (N = 25) were compared with women diagnosed with IBD (N = 25) on measures of history of abuse, self-blame, and self-silencing. RESULTS: It was found that women in the IBS sample scored significantly higher on emotional abuse, self-blame, and self-silencing than did women in the IBD sample. These three variables were also found to be significantly intercorrelated in both the IBS and IBD samples. Finally, emotional abuse was significantly higher in IBS patients than in IBD patients beyond the differences accounted for by physical and/or sexual abuse history. CONCLUSIONS: These findings empirically demonstrate an association between IBS and emotional abuse, as well as a possible connection with psychosocial variables, that may mediate the connection between emotional abuse and functional bowel symptoms. We suggest that these variables be further evaluated in the context of clinically relevant research on IBS. 相似文献