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101.
Healthcare information systems (HISs) are often implemented to enhance the quality of care and the degree to which it is patient-centered, as well as to improve the efficiency and safety of services. However, the outcomes of HIS implementations have not met expectations. We set out to organize the knowledge gained in qualitative studies performed in association with HIS implementations and to use this knowledge to outline an updated structure for implementation planning. A multi-disciplinary team performed the analyses in order to cover as many aspects of the primary studies as possible. We found that merely implementing an HIS will not automatically increase organizational efficiency. Strategic, tactical, and operational actions have to be taken into consideration, including management involvement, integration in healthcare workflow, establishing compatibility between software and hardware and, most importantly, user involvement, education and training. The results should be interpreted as a high-order scheme, and not a predictive theory.  相似文献   
102.
Purpose  The present investigation looks in detail at the causes and types of health incidents reported by 6,300 mainly smallholder agrochemical users in 24 countries during 2005 and 2006. Methods  The investigation is based on a questionnaire survey of knowledge, attitude and practice that concentrated on the sequence of events from purchasing the pesticide to disposal. Information was also collected about health problems experienced while using agrochemicals. The survey targeted mainly smallholder knapsack spray operators who were expected to be at a highest risk of exposure. Results  In the 12 months prior to interview, 1.2% of users reported an agrochemical-related incident that required hospital treatment, 5.8% reported an incident requiring at least trained medical treatment but not hospitalisation and 19.8% reported only a minor sign or symptom. Users who had experienced an incident involving agricultural equipment were 3.38 (95% CI 2.29–4.99) times more likely to experience an agrochemical-related health incident, but confident users who felt that their use of personal protective equipment while spraying was best practice were 0.60 (95% CI 0.44–0.84) times less likely to experience such an incident. Over 80% of product-related incidents were caused by insecticides and the incidence rate per spraying time for incidents linked to insecticides was significantly higher than that for fungicides or herbicides. Headache/dizziness and nausea/vomiting, often smell related, were the most common symptoms reported by users who listed agrochemical products that had caused them health problems (52 and 38% of product mentions, respectively). Conclusions  In most countries, the incidence of serious health effects was low; however, there was a high incidence of minor signs and symptoms in a few countries, especially in Africa. A disproportionate number of incidents occurred during insecticide use relative to the time that they were sprayed. Failure to exercise caution as indicated by whether users had incidents involving agricultural equipment or livestock, and lack of confidence in their practices were the most important predictors of agrochemical-related incidents.  相似文献   
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104.

Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.  相似文献   
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107.

Background  

Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.  相似文献   
108.
Phase II clinical trials are performed to investigate whether a novel treatment shows sufficient promise of efficacy to justify its evaluation in a subsequent definitive phase III trial, and they are often also used to select the dose to take forward. In this paper we discuss different design proposals for a phase II trial in which three active treatment doses and a placebo control are to be compared in terms of a single‐ordered categorical endpoint. The sample size requirements for one‐stage and two‐stage designs are derived, based on an approach similar to that of Dunnett. Detailed computations are prepared for an illustrative example concerning a study in stroke. Allowance for early stopping for futility is made. Simulations are used to verify that the specified type I error and power requirements are valid, despite certain approximations used in the derivation of sample size. The advantages and disadvantages of the different designs are discussed, and the scope for extending the approach to different forms of endpoint is considered. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
109.
BackgroundThe incidence of strictures developing after gastrojejunostomy has been reported to range from 3% to 31%. We found an unacceptably high stricture rate (13%) using a 21-mm circular stapler. Attempts to use the 25-mm circular stapler were frustrated by disparities between the size of the instrument and the patient's anatomy. We, therefore, modified the technique to accomplish the anastomosis with the linear stapler and hand sewing (LSA) at community hospitals in Southern California.MethodsA total of 124 anastomoses were accomplished with the circular stapler (CSA) followed by 100 anastomoses using the LSA technique. Drains were used routinely with the CSA technique but were used only selectively with the LSA technique. Stricture was defined as that requiring endoscopic dilation for symptoms. Leaks were confirmed radiologically or surgically, and bleeding was defined as the need for transfusion. Our analysis used the Student t test and Fisher's exact test, with P <.05 considered statistically significant.ResultsNo patient died. The LSA technique was faster and resulted in significantly fewer postoperative strictures and complications compared with the CSA technique.ConclusionThe results of our study have shown that the LSA technique, as described, is preferable to the CSA technique.  相似文献   
110.
Mutations in PAX6/Pax6 lead to a variety of ocular anomalies in humans and mice. The aim of the study was to characterise the ocular abnormalities caused by the missense Pax6Leca4 mutation and compare them to published observations on Pax6 alleles that are functionally equivalent to Pax6 null alleles (such as Pax6Sey and Pax6Sey-Neu) and human inherited eye diseases. Ocular features of homozygous Pax6Leca4/Leca4 and heterozygous Pax6Leca4/+ embryos at E12.5-E18.5, heterozygous Pax6Leca4/+ young mice at P18 and heterozygous Pax6Leca4/+ adults at 12 weeks were analysed histologically with their wild-type Pax6+/+ littermates. Homozygous Pax6Leca4/Leca4 fetuses died perinatally with no eyes although an optic cup rudiment with pigmented cells developed. Pax6Leca4/+ mice were microphthalmic and a range of other severe ocular phenotypes affected both the anterior and the posterior segments. In contrast to Pax6+/−, the Pax6Leca4/+ eyes had no goblet cells in the corneal epithelium, the iris was not hypoplastic and there was no lens-corneal epithelial plug. However, microphthalmia was more severe, corneal vascularisation occurred earlier (during fetal stages), pigmented cells were present in the vitreous and corneal stroma and the ciliary body was malformed or abnormal. These results show that, although Pax6Leca4/+ lacked some eye abnormalities commonly seen in Pax6Sey/+ and Pax6Sey-Neu/+ eyes, in most respects their eyes were more severely affected. These differences probably reflect both differences between the Pax6Leca4 and the Pax6Sey-Neu mutations and differences in modifier gene expression in different genetic backgrounds. The presence of pigmented cells in the cornea is a novel observation. Some Pax6Leca4/+ ocular abnormalities were similar to those present in human Peters' anomaly and persistent hyperplastic primary vitreous (PHPV) so Pax6Leca4/+ mice provide a useful model for some inherited eye diseases.  相似文献   
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