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51.
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Concurrent infection is a risk factor for abdominal wound dehiscence. We reviewed our experience with fascial dehiscence to determine the incidence and to identify prognostic factors for associated intra-abdominal infection. Over a 7-year period, 107 patients with abdominal wound dehiscence were identified. Seventeen were managed nonoperatively, and 90 underwent exploratory laparotomy, 43 of whom had no intra-abdominal pathology and 47 of whom had intra-abdominal infections. Demographic factors, comorbid diseases, and potential indicators of systemic infection did not distinguish patients with intra-abdominal infection from those without. Patients with an intra-abdominal infection were more likely to have undergone an emergency operation (74% vs 48%; P < 0.02), an operation on the colon (55% vs 25%; P < 0.005), or an operation with a higher wound classification (P < 0.02). Mortality was higher in patients with intra-abdominal infection than in those without (44% vs 20%; P < 0.02). Wound dehiscence after emergent operations, and operations with a higher wound classification, especially those involving the colon, should raise concern for intra-abdominal infection. Thorough abdominal exploration should be performed at the time of dehiscence repair. Before nonoperative management is chosen, intra-abdominal infection should be excluded. 相似文献
53.
We have studied the efficacy of two extradural infusions (10 ml h-1) in 50 patients in active labour. Patients in the diamorphine group (n = 25) received 0.0625% plain bupivacaine 6.25 mg h-1 mixed with 0.005% diamorphine 0.5 mg h-1 and those in the control group (n = 25) received 0.125% plain bupivacaine 12.5 mg h-1. Both groups received intermittent "top-ups" of 0.25% bupivacaine 10 ml when indicated. Although median pain scores during the infusion were similar in both groups, patients in the diamorphine group indicated greater satisfaction with the infusion (88% very satisfied, compared with 52% in the control group (P < 0.02)). There were no differences in the incidence of hypotension, instrumental vaginal delivery, number of "top-ups", duration of the second stage or extent of motor block. However, patients in the diamorphine group had a high incidence of pruritus (44%, compared with 0% in the control group (P < 0.01)). 相似文献
54.
Higher incidence of Gastrospirillum sp. in swine with gastric ulcer of the pars oesophagea 总被引:1,自引:0,他引:1
AJ Barbosa JC Silva AM Nogueira E Paulino Júnior CR Miranda 《Canadian Metallurgical Quarterly》1995,32(2):134-139
Gastric ulcer in swine is characterized by an area of acid-peptic digestion, occurs usually in the pars oesophagea of the stomach, and has unknown etiopathogenesis. The present work was carried out to investigate the prevalence of the newly described spiral-shaped microorganism Gastrospirillum sp. ("Gastrospirillum suis") in stomachs of abattoir pigs with and without gastric ulcer. Stomachs were removed from 32 consecutive pigs presenting apparently normal mucosa and from 32 additional consecutive pigs presenting frank, chronic gastric ulcer of the pars oesophagea. Fragments of antral, oxyntic, cardiac and pars oesophagea regions were taken from each stomach and processed for histology and for identification of Gastrospirillum sp. in tissue sections. The microorganisms were identified mainly in the mucous layer and in gastric foveolas of the antral and oxyntic mucosa. Forty pigs (62.5%) were positive for Gastrospirillum sp.; among them, 27 (67.5%) had gastric ulcer, and 13 (32.5%) had no ulcer. Twenty-four pigs (37.5%) were negative for Gastrospirillum sp.; among them, five (20.8%) presented with gastric ulcer, and 19 (79.2%) had no ulcer. There was a significant difference between pigs with and without gastric ulcer in regard to the presence of Gastrospirillum sp. (P < 0.01). The spiral-shaped microorganism Gastrospirillum sp. that inhabits the stomach of pigs should be considered a possible factor connected with the etiopathogenesis of swine gastric ulcer. 相似文献
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CR Logan 《Canadian Metallurgical Quarterly》1996,31(3):31-53
The ubiquitous expression of anti-homosexual responses and the lack of consensus regarding the characterization of such responses served as the impetus for this study. The purpose of this study was to investigate the nature of anti-homosexual responses as reported by male and female undergraduates. Participants in the study were asked to respond to both a lesbian and a gay target questionnaire. Responses were measured as either phobic or prejudicial. Findings indicated that there is little, if any, evidence to support the characterization of anti-homosexual responses as a phobia. Responses to prejudicial items suggested that anti-homosexual responses lie primarily within the realm of prejudice. Results also indicated that males were less tolerant than females of gays and lesbians and males and females respond differentially according to same-sex target. The implications of using a more accurate term such as "homoprejudice" to characterize anti-homosexual responses are discussed. Additionally, avenues for future research are addressed. 相似文献
57.
SD Colman SA Rasmussen VT Ho CR Abernathy MR Wallace 《Canadian Metallurgical Quarterly》1996,58(3):484-490
Using loss of heterozygosity analysis, a method designed to detect moderate to large gene deletions, we have identified a new-mutation neurofibromatosis type 1 (NF1) patient who is somatically mosaic for a large maternally derived deletion in the NF1 gene region. The deletion extends at least from exon 4 near the 5' end of the gene to intron 39 near the 3' end. The gene-coding region is, therefore, mostly or entirely deleted, encompassing a loss of > or = 100 kb. We hypothesize that the deletion occurred at a relatively early developmental timepoint, since signs of NF1 in this patient are not confined to a specific body region, as seen in "segmental" NF, and since both mesodermally and ectodermally derived cells are affected. This report provides the first molecular evidence of somatic mosaicism in NF1 and, taken together with a recent report of germ-line mosaicism in NF1, adds credence to the concept that mosaicism plays an important role in phenotypic and genetic aspects of NF1 and may even be a relatively common phenomenon. 相似文献
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59.
根据MOPAC2009软件包中PM6算法得到的分子描述符研究半透膜仪(SPMDs)采集大气中多氯联苯(PCBs)采样速度(R_(air))的定量构效关系(QSPR)模型,并分析影响R_(air)的关键因素。以半经验PM6算法得到的分子量子化学描述符作为预测变量,采用偏最小二乘算法(PLS)构建了R_(air)的QSPR模型。根据交叉验证,所得到的最佳模型中PLS成分解释的因变量的累积变异(Q~2_(cum))为0.683,这表明该模型具有良好的预测能力和稳健性。通过外部验证和将实验测得的R_(air)与预测得到的R_(air)进行比较,对所构建模型的稳定性和可靠性进行了验证,结果表明无论是训练组还是预测组,其预测值与实测值间均具有较好的线性关系,线性相关系数均大于0.8376。对PCBs采样速度R_(air)的主要影响因素为PCBs与SPMDs中甘油三油酸酯分子间的相互作用大小和为将PCBs溶解在甘油三油酸酯中形成洞穴所需能量要求。 相似文献
60.
An empirical model of a liquid crystalline (L alpha phase) phosphatidylcholine (PC) bilayer interface is presented along with a function which calculates the position-dependent energy of associated solutes. The model approximates the interface as a gradual two-step transition, the first step being from an aqueous phase to a phase of reduced polarity, but which maintains a high enough concentration of water and/or polar head group moieties to satisfy the hydrogen bond-forming potential of the solute. The second transition is from the hydrogen bonding/low polarity region to an effectively anhydrous hydrocarbon phase. The "interfacial energies" of solutes within this variable medium are calculated based upon atomic positions and atomic parameters describing general polarity and hydrogen bond donor/acceptor propensities. This function was tested for its ability to reproduce experimental water-solvent partitioning energies and water-bilayer partitioning data. In both cases, the experimental data was reproduced fairly well. Energy minimizations carried out on beta-hexyl glucopyranoside led to identification of a global minimum for the interface-associated glycolipid which exhibited glycosidic torsion angles in agreement with prior results (Hare, B.J., K.P. Howard, and J.H. Prestegard. 1993. Biophys. J. 64:392-398). Molecular dynamics simulations carried out upon this same molecule within the simulated interface led to results which were consistent with a number of experimentally based conclusions from previous work, but failed to quantitatively reproduce an available NMR quadrupolar/dipolar coupling data set (Sanders, C.R., and J.H. Prestegard. 1991. J. Am. Chem. Soc. 113:1987-1996). The proposed model and functions are readily incorporated into computational energy modeling algorithms and may prove useful in future studies of membrane-associated molecules. 相似文献