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51.
Purpose: The trend toward avoidance of a colostomy at both elective and emergency large-bowel surgery is partly driven by the perceived morbidity and low closure rates of temporary stomas. The aim of this study was to examine whether significant colostomy-related morbidity remains persistently high. METHODS: To examine this, we reviewed 120 patients with a potentially reversible colostomy performed during either elective or emergency large-bowel surgery during a seven-year period. RESULTS Forty-seven patients underwent elective and 73 patients underwent emergency colonic or colorectal resection. Fifty-eight patients had colorectal carcinoma (48.3 percent), diverticular disease accounted for 39 patients (32.5 percent), and a miscellaneous group of 23 patients (19.2 percent) made-up the remainder. Seven patients died, all in the emergency group (9.6 percent). Colostomy-related morbidity, which included stenosis, retraction, prolapse, and hernia formation, occurred in 19.2 percent of patients, with no difference between the elective (14.9 percent) and emergency (21.9 percent) groups or underlying pathologic condition. Colostomy closure was performed initially in 71 patients (59.2 percent). Highest closure rates occurred in the diverticular group (84.6 percent), followed by the colorectal carcinoma group (48.3 percent), and then the miscellaneous group (43.5 percent). One patient died undergoing colostomy closure, and complications occurred in 25 patients (35.2 percent), requiring fashioning of a second colostomy in eight patients, two of whom were closed. Final colostomy closure rate was 54.2 percent. CONCLUSIONS: This study confirms the contention that both formation and closure of defunctioning colostomies are associated with significant complications; furthermore, approximately one-half of patients will not have their colostomy closed.  相似文献   
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Band 3 and glycophorin A (GPA) are the 2 most abundant integral proteins in the human erythrocyte membrane. Earlier studies suggested that the 2 proteins may associate not only in the mature erythrocyte membrane, but also during their posttranslational processing and intracellular trafficking. The purpose of this study was to directly examine the GPA-band 3 interaction in vivo and determine the nature of this association during erythroid membrane biogenesis. Transgenic mice were generated expressing the human glycophorin A gene and were used to examine how the induction of human GPA expression affected the levels of murine GPA and band 3 expression in the red cell membrane. Murine GPA expression was reduced in erythrocytes expressing human GPA, whereas the level of band 3 expression remained constant, implying a tight coupling of band 3 and GPA expression in the membrane of mature red cells. In vivo GPA dimerization was not modulated solely by the GPA transmembrane motif, but the distance between this motif and the basic residues on the cytoplasmic side of the transmembrane domain may also be important. In addition, GPA monomers with varying degrees of glycosylation dimerized, providing clear evidence that carbohydrate structures on the extracellular domain do not affect dimerization. The association between the multiple transmembrane-spanning protein, band 3, and the single transmembrane-spanning sialoglycoprotein, GPA, may serve as a model for interactions of other multi-pass and single-pass polypeptides during membrane biogenesis.  相似文献   
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BackgroundTreatments for health care–associated infections (HAIs) caused by antibiotic-resistant bacteria and Clostridium difficile are limited, and some patients have developed untreatable infections. Evidence-supported interventions are available, but coordinated approaches to interrupt the spread of HAIs could have a greater impact on reversing the increasing incidence of these infections than independent facility-based program efforts.MethodsData from CDC’s National Healthcare Safety Network and Emerging Infections Program were analyzed to project the number of health care–associated infections from antibiotic-resistant bacteria or C. difficile both with and without a large scale national intervention that would include interrupting transmission and improved antibiotic stewardship. As an example, the impact of reducing transmission of one antibiotic-resistant infection (carbapenem-resistant Enterobacteriaceae [CRE]) on cumulative prevalence and number of HAI transmission events within interconnected groups of health care facilities was modeled using two distinct approaches, a large scale and a smaller scale health care network.ResultsImmediate nationwide infection control and antibiotic stewardship interventions, over 5 years, could avert an estimated 619,000 HAIs resulting from CRE, multidrug-resistant Pseudomonas aeruginosa, invasive methicillin-resistant Staphylococcus aureus (MRSA), or C. difficile. Compared with independent efforts, a coordinated response to prevent CRE spread across a group of inter-connected health care facilities resulted in a cumulative 74% reduction in acquisitions over 5 years in a 10-facility network model, and 55% reduction over 15 years in a 102-facility network model.ConclusionsWith effective action now, more than half a million antibiotic-resistant health care–associated infections could be prevented over 5 years. Models representing both large and small groups of interconnected health care facilities illustrate that a coordinated approach to interrupting transmission is more effective than historical independent facility-based efforts.Implications for Public HealthPublic health–led coordinated prevention approaches have the potential to more completely address the emergence and dissemination of these antibiotic-resistant organisms and C. difficile than independent facility–based efforts.  相似文献   
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Background

A public health research system is the bedrock of health systems to improve population health, system responsiveness, and equity. An international concern, referred to as the 10/90 gap, is that less than 10% of global funds are devoted to diseases or conditions that account for 90% of the global disease burden, particularly in developing countries. Palestinian health research is progressing, but it is not sufficiently investigated, with a remarkable knowledge gap on its conceptualisation, stewardship, stakeholders, and capacity and resources. The aim of this study was to understand the Palestinian public health research system by investigating challenges related to the system components that need to be strengthened.

Methods

The study was done in the Gaza Strip and West Bank in the occupied Palestinian territory between January and July, 2016. We targeted relevant government institutions, academic schools, and large local and international health agencies. Data were collected through 52 in-depth interviews and six focus group discussions with policy makers, academics, and experts. Participants and institutions were selected purposively on the basis of stated criteria and peer review. Data were translated, transcribed, checked, and imported into MAXQDA 12 for thematic and content analysis. Approvals were obtained from The Research Commission of Swiss TPH, “Ethikkommission Nordwest- und Zentralschweiz” (EKNZ) in Switzerland, the Palestinian Ministry of Health, Helsinki Committee, and An-Najah National University in Palestine.

Findings

The health research system is not well structured, whereas public health research is promising but probably without regulated national policies. Most experts emphasised that governance is not clearly framed in managing research functions, whereas public health research activities are most likely scattered and individually driven. There is a consensus that the concept of the health research system is misunderstood and that the system is underperforming because of various problems such as resource insufficiency. Research is also not fundamentally at the heart of the political agenda or itemised in central budgets. Besides workforce scarcity with poor incentives and infrastructure, priorities in public health research are inconsistent and efforts are uncoordinated with poor multidisciplinary research. Dissemination and application of the public health research agenda among stakeholders are lacking. The research culture seems to be insufficiently cultivated. The international support to the public health research system is inconspicuous although some initiatives have been successful. The overall environment in the occupied Palestinian territory formed one of obstacles of the public health research system. Precious opportunities are proposed to strengthen public health research system synergistically through best strategies.

Interpretation

The occupied Palestinian territory is a fertile place for growth of public health research system activity. Development actions should therefore be taken to get the system materialised by reactivating a unified governance body that cooperatively manages the national policies, capacities, priorities, research utilisation, and application of the public health research system.

Funding

The Swiss Federation and Swiss Tropical and Public Health Institute.  相似文献   
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The molluscicidal activity of crushed seed pods of Swartzia madagascariensis was assessed by laboratory and field trials. Mature dry seed pods were ground and extracted in tap water for 24 h. Water extracts exerted a significant molluscicidal activity against Bulinus globosus up to dilutions of 100 mg of ground pods per litre. The chromatographically isolated saponin (1) responsible for the molluscicidal activity showed a toxicity of LC 100 at 3 mg/l after exposure of B. globosus and Biomphalaria glabrata for 24 h. Saponin (1) could be identified by FAB-MS and 13C-NMR-spectroscopy as oleanolic acid-3-O-beta-D-glucuronopyranosyl (1----3)-alpha-L-rhamnopyranoside. Two field trials with S. madagascariensis pod extracts in ponds (60 and 160 m3) harbouring dense populations of B. globosus compared well with the laboratory findings and showed the efficiency of the molluscicide in a natural habitat. A single application of the plant molluscicide significantly reduced the populations of B. globusus. The toxicity of S. madagascariensis pod extracts to non-target organisms remains an obstacle for its use in certain situations where schistosomiasis control is envisaged and where S. madagascariensis is found. However, S. madagascariensis is a valid candidate molluscicide which may be applied in selected epidemiological settings as part of integrated schistosomiasis control measures.  相似文献   
59.
Schizosaccharomyces pombe cells were transformed with an S. pombe expression vector containing a full-length cDNA of the Chlorella hexose transporter. The transformed cells accumulated 3-O-methylglucose up to 10-fold, whereas wild-type S. pombe and control transformants could only equilibrate this sugar analogue. In a pH-jump experiment, in which extracellular pH was lowered by 1.9 units, the accumulation ratio was increased in transformed cells but not in control cells. This result indicates that the gene product, Chlorella H+/glucose-symporter protein, and a pH gradient suffice for active sugar uptake. Km values for glucose, 6-deoxyglucose, and 3-O-methylglucose of 1.5 x 10(-5) M, 2.7 x 10(-4) M, and 1.0 x 10(-3) M, respectively, were identical in Chlorella and in S. pombe cells transformed with Chlorella cDNA and approximately 100-fold lower than those of the endogenous transport system of S. pombe.  相似文献   
60.
The prevalence of antibodies to human immunodeficiency virus (HIV = LAV/HTLV-III) in a rural population from the Ifakara area in southeastern Tanzania was investigated. Sera from 286 individuals collected from 1982 to 1984 in connection with a study on liver disorders were tested by an ELISA. Fifty-two (18.2%) of the sera were found positive. While the positives were largely confirmed by one commercial ELISA, they were completely negative by two others. Confirmatory testing by Western blot and competition Western blot showed that the reactivity detected by more sensitive of these assays was largely due to IgG antibodies binding to the HIV core (gag) proteins p17, its precursor p55 and, in some cases, p24. These tests also indicated, however, that the reactive antibodies could not have been elicited by HIV, but possibly by an unknown retrovirus or another cross-reactive agent. Thus, by 1984, the area investigated was largely free of HIV infection, but a significant proportion of its population may harbor another retrovirus of unknown pathogenicity.  相似文献   
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