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排序方式: 共有709条查询结果,搜索用时 15 毫秒
1.
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
2.
Prenatal nicotine exposure selectively affects perinatal forebrain aromatase activity and fetal adrenal function in male rats. 总被引:2,自引:0,他引:2
N I von Ziegler M Schlumpf W Lichtensteiger 《Brain research. Developmental brain research》1991,62(1):23-31
Previous studies have revealed effects of prenatal nicotine treatment on fetal plasma testosterone and perinatal sexual brain differentiation in the rat. In an attempt to further elucidate the processes underlying this action of nicotine, we studied the effect of the drug on brain steroid aromatase which converts androgens to estrogens and is known to be important in sexual brain differentiation. Aromatase activity (AA) was measured by the conversion of [1 beta-3H]-androstenedione to estrone in a brain region comprising preoptic, hypothalamic and amygdaloid areas. In untreated animals, the development of AA between gestational day (GD) 18 and postnatal day (PN) 15 was similar in both sexes, except for a significant drop of AA in female brain at PN6, i.e., during the later part of the critical period for sexual brain differentiation. When time-pregnant rats were treated with nicotine delivered by an osmotic minipump for either one week (2 mg/kg/d or 6 mg/kg/d from GD12) or two weeks (6 mg/kg/d from GD8), their male offspring showed a decrease of AA to female levels at PN6, the sex difference existing at this stage thus being abolished. AA of offspring from dams bearing tartaric acid-containing minipumps or sham-operated at GD8 or GD12 was identical to that of untreated controls. No drug effect was seen in female fetuses and offspring. Sex differences in the developmental effect of nicotine may thus involve brain aromatase. An additional sex-dependent effect of nicotine was observed in the male fetal adrenal axis at GD18. Whether the drug effects on the two steroid hormone systems are interrelated, remains to be elucidated. 相似文献
3.
R Schlumpf P Morel J J Loveras R M Condie A Matas J Kurle J S Najarian D E Sutherland 《Transplantation proceedings》1991,23(5):2362-2365
The delayed contralateral nephrectomy procedure (three-step) produced inconsistent results, indicating that the preserved autotransplanted kidney tends to remain unfunctional and to regenerate incompletely unless the demand for work is placed upon it. Omission of HES in UW (UW-plain) did not affect preservation success, but resulted in increased graft edema. Substitution of HES in UW with plasma (SGF-V) or albumin (MAlb) gave significantly worse results than UW-like solutions with or without synthetic colloids. Replacement of HES in UW with UMdex-70 or UMdex-500 gave nonsignificantly worse results than UW-like solutions with or without synthetic colloids. The use of UMdex-40 as the main colloid in UW cheapened the solution, equalled the preservation success of UW and UW-plain but surpassed UW-plain in edema prevention, and exceeded UW concerning recovery of graft microcirculation. 相似文献
4.
Margret S. Magid Wallace G. Campbell Jr MD Sutini Ngadiman Thomas A. Godwin MD Robert Ward 《Fetal and pediatric pathology》1997,17(2):303-314
We report a case of an infantile myofibromatosis with hemangiopericytoma-like features arising in the tongue of a 5-month-old female infant. Many authors now classify neoplasms as infantile myofibromatosis that were previously called infantile hemangiopericytoma. The ultrastructural features of our tumor illustrate its biphasic nature and provide a possible explanation for its histogenesis. Infantile myofibromatosis, including those diagnosed as infantile hemangiopericytomas, rarely arise in any intraoral location. Despite the generally good prognosis associated with these neoplasms, complete surgical excision is recommended to avoid recurrences. 相似文献
5.
Efficiency of the ortho VITROS assay for detection of hepatitis C virus-specific antibodies increased by elimination of supplemental testing of samples with very low sample-to-cutoff ratios 下载免费PDF全文
Oethinger M Mayo DR Falcone J Barua PK Griffith BP 《Journal of clinical microbiology》2005,43(5):2477-2480
The clinical significance of specimens with low sample-to-cutoff (S/Co) ratios in the Ortho VITROS chemiluminescence assay (CIA) for detection of antibodies to hepatitis C virus (HCV) was evaluated. In one study of 482 CIA-reactive samples, none of the 83 samples with S/Co ratios of < 5 was HCV RNA positive. In a subsequent study, 332 samples with S/Co ratios of between 1 and 20 were tested with the recombinant immunoblot assay (RIBA). None of the 163 samples with S/Co ratios of < 5 was RIBA positive, 83% were RIBA negative, and 28 samples (18%) were RIBA indeterminate. HCV RNA and/or clinical evidence of hepatitis was not found in the 27 indeterminate cases examined. These results show that over 99% of samples with very low S/Co ratios (< or = 5) have no evidence of HCV infection. Therefore, we suggest that the HCV antibody testing algorithm for the VITROS assay might be modified to eliminate supplemental testing of samples with very low S/Co ratios. 相似文献
6.
Clone-based systematic haplotyping (CSH): a procedure for physical haplotyping of whole genomes 总被引:4,自引:0,他引:4 下载免费PDF全文
Burgtorf C Kepper P Hoehe M Schmitt C Reinhardt R Lehrach H Sauer S 《Genome research》2003,13(12):2717-2724
We present a novel methodology to determine the phase of single-nucleotide polymorphisms (SNPs) on a chromosome, which we term clone-based systematic haplotyping (CSH). The CSH procedure is based on separating the allelic chromosomes of a diploid genome by fosmid/cosmid cloning, and subsequent SNP typing of 96 clone pools, each representing approximately 10% of the genome. The pools are screened by PCR for the sequence of interest, followed by SNP typing on the PCR products using the GOOD assay. We demonstrate that by CSH, the haplotype of SNPs separated by more than 50 kilobases can definitely be assigned. We propose this method as being suitable for constructing maps of ancestral haplotypes, analysis of complex diseases, and for diagnosis of rare defects in which the molecular haplotype is crucial. In addition, by amplifying the initial DNA by many orders of magnitude, the original DNA resource is effectively immortalized, enabling the haplotyping of hundreds of thousands of SNPs per individual. 相似文献
7.
8.
Podlowski S Wenzel K Luther HP Müller J Bramlage P Baumann G Felix SB Speer A Hetzer R Köpke K Hoehe MR Wallukat G 《Journal of molecular medicine (Berlin, Germany)》2000,78(2):87-93
A substantial body of evidence suggests involvement of the human beta1-adrenoceptor (beta1-AR) gene in the pathophysiology of dilated cardiomyopathy (DCM), a severe heart disease of significant public health impact. Beta1-AR-mediated signal transduction is dramatically altered due to downregulation, resulting in an impairment of myocardial response. The important role of genetic factors in idiopathic dilated cardiomyopathy (IDCM) recently recognized, we analyzed this prime candidate gene for genetic variation in carefully selected patients and controls. In this preliminary study, 18 single nucleotide polymorphisms were observed, 17 of which were located in the N-terminal and C-terminal region of the coding exon, resulting in 7 amino acid exchanges: Ser-49-Gly, Ala-59-Ser, Gly-389-Arg, Arg-399-Cys, His-402-Arg, Thr-404-Ala, and Pro-418-Ala. These mutations resulted in 11 different beta1-AR genotypes. Importantly, the genotypes carrying the Ser-49-Gly mutation in the N-terminus of the molecule in a heterozygous or homozygous form were observed significantly more frequently in the group of IDCM patients. The present results may provide a clue on the molecular mechanisms involved in IDCM, and add moreover interesting information on nature, distribution, and evolutionary aspects of sequence variation in human adrenergic receptor genes. 相似文献
9.
New anastomosis technique for (laparoscopic) instrumental small-diameter anastomosis 总被引:3,自引:1,他引:2
O. Schöb R. Schmid R. Schlumpf H. P. Klotz M. Spiess F. Largiadèr 《Surgical endoscopy》1995,9(4):444-449
This study presents a new technique for visceral anastomosis. The principle consists of connecting the two parts to be anastomosed around a reabsorbable stent which is transluminally introduced into a small-diameter viscus, where it is fixed. Advancing a larger tube along the axis of the machine, the larger, perforated viscus is inverted and pulled over the stent, and finally a rubber band pops off the machine endoluminally in order to fix the intestinal walls in seroserosal contact onto the stent. To evaluate this micro anastomosis, a biliary bypass (choledochojejunostomy and roux-en-y-loop) was performed in ten pigs. Nine of ten animals showed biliary bypass with good runoff in contrast radiography and completely reabsorbed stent after a 3-month follow-up. Weight gain, bilirubin, and alkaline phosphatase were normal. This technology demonstrates a safe and quick way to perform instrumental micro anastomosis without remnant foreign material.Presented as a poster at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, TN, USA, 18–19 April 1994 相似文献
10.
Prenatal exposure to diazepam and other benzodiazepines (BDZ) has been found to result in a marked reduction of T-lymphocyte proliferation during postnatal development of rats. In search for pathogenic changes underlying this effect, we investigated the mitogen lipopolysaccharide (LPS) and concanavalin A (ConA) stimulated release of tumour necrosis factor (TNF)- by mixed splenocytes of male offspring from Long Evans rats treated with 1.25 mg/kg per day diazepam from gestational day 14 to 20. In response to LPS, TNF- release was found to be significantly lower in mixed splenocytes of two- and four-week-old treated than in control offspring. However, at eight weeks of age, prenatally diazepam-treated animals showed a significantly higher LPS-induced TNF- release than control rats. Since monocytes/macrophages represent a major source of TNF-, additional experiments were performed on purified spleen macrophages and lymphocytes stimulated with LPS. TNF- release was only detectable in supernatants of adherent spleen macrophages and not in supernatants of lymphocytes. Thus, our data indicate that a disturbance in TNF- release from macrophages is involved in the deficient immune response of prenatally diazepam-exposed rats. 相似文献