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101.
Laparoscopic cholecystectomy (LC) using electrocoagulation was successfully performed in 56 out of 58 selected patients. Cholangiography was performed in 53 patients. Six patients had common duct stones; five were unsuspected preoperatively. After the gallbladder was removed, three patients underwent open common duct exploration. In another five cases, anatomical anomalies were discovered. Cholangiography performed via the cystic duct before any structures are divided can prevent the most serious complication--common duct injury. Cholangiography should be attempted on all patients undergoing LC.  相似文献   
102.
This study focuses on the influence of distance, transport and accessibility on the use of health services in Kingston, Jamaica. It reviews various factors affecting the use of health care with particular reference to Third World cities and presents results from a case study of utilization in the Kingston Metropolitan Area. Three pairs of sites of contrasting social status were selected and 50 respondents questioned in each about spatial patterns of primary health care (PHC) attendance. Types of facility attended, mode of transport, travel times, distance and frequency of utilization were discussed. Some distinctive differences appeared between low and high status site respondents with regard to distances to facilities and travel times, which were almost always higher for the low status respondents. Most respondents were not using their nearest facilities, for varying reasons which included, for poorer respondents, need to attend frequently distant public facilities and, for wealthier respondents, loyalty to old family doctors and use of company-related doctors. The mobility of the higher status respondents afforded them considerable choice of locations used for health care and their attendance was much more convenient than that of lower status respondents. Utilization rates were somewhat higher in the high status sites although not to the extent found by some earlier studies in similar settings.  相似文献   
103.
104.
An interview study investigating attitudinal and other factors influencing the selection of primary medical care (PMC) agency is described. It focuses on adult patients excluding those with trauma of medical/surgical emergencies and was conducted in part of the Western Region of Melbourne in late 1983, the period immediately prior to the introduction of Medicare. It is based on a cross-sectional survey of in-hours attenders of eight general practices (GP), the Western Region (Community) Health Centre (WRCHC) and the general clinic of the casualty department at the Western General Hospital (WGH). Attenders of these different services differed significantly in their socio-demographic characteristics. WGH attenders were significantly younger and had migrated from non-English speaking countries significantly more often. Male attenders at the WGH had significantly lower socioeconomic status. 71 per cent being not in the workforce. The most commonly stated reasons for attendance at particular services generally were “closeness to home, work”, “recommendation” and “good service”. Reasons given by attenders at the different clinics generally were similar. However GP attenders offered “good service” significantly more often as a reason for choice; WGH attenders offered “cheap/economic reasons” significantly more often and “recommendation” significantly less so. WRCHC attenders offered “workers' compensation” significantly more often. Thirty per cent of attenders overall had attended other than their current clinic during their past three to four illness episodes. While a large majority of patients still attend GP for PMC it is concluded that a pluralist model recognising the legitimacy of different PMC arrangements and multiple use of them by individuals best meets community need. This is likely to be even more true under Medicare. It is concluded that instrumental factors and social networks are important in the selection of PMC, particularly given the limited knowledge of respondents about health services. It is also concluded that cost and economic factors have been given undue weight in selection of primary medical care agency. The use of the WGH casualty department by groups not in the work force, given no real financial advantage in doing so, requires further study.  相似文献   
105.
Variegate porphyria (VP) is an autosomal dominant disorder characterised by a partial defect in the activity of protoporphyrinogen oxidase (PPO), and has recently been genetically linked to the PPO gene on chromosome 1q22-23 (Z=6.62). In this study, we identified a mutation in the PPO gene in a patient with VP and two unaffected family members. The mutation consisted of a previously unreported T to C transition in exon 13 of the PPO gene, resulting in the substitution of a polar serine by a non-polar proline (S450P). This serine residue is evolutionarily highly conserved in man, mouse, and Bacillus subtilis, attesting to the importance of this residue. Interestingly, the gene for Gardner's syndrome (FAP) also segregates in this family, independently of the VP mutation. Gardner's syndrome or familial adenomatous polyposis (FAP) is also an autosomal dominantly inherited genodermatosis, and typically presents with colorectal cancer in early adult life secondary to extensive adenomatous polyps of the colon. The specific gene on chromosome 5 that is the site of the mutation in this disorder is known as APC (adenomatous polyposis coli), and the gene has been genetically linked to the region of 5q22.  相似文献   
106.
We studied the pharmacokinetics of intravenously and orally administered lamivudine at six dose levels ranging from 0.5 to 10 mg/kg of body weight in 52 children with human immunodeficiency virus infection. A two-compartment model with first-order elimination from the central compartment was simultaneously fitted to the serum drug concentration-time data obtained after intravenous and oral administration. The maximal concentration at the end of the 1-h intravenous infusion and the area under the concentration-time curve after oral and intravenous administration increased proportionally with the dose. The mean clearance of lamivudine (± standard deviation) in the children was 0.53 ± 0.19 liter/kg/h (229 ± 77 ml/min/m2 of body surface area), and the mean half-lives at the distribution and elimination phases were 0.23 ± 0.18 and 2.2 ± 2.1 h, respectively. Clearance was age dependent when normalized to body weight but age independent when normalized to body surface area. Lamivudine was rapidly absorbed after oral administration, and 66% ± 25% of the oral dose was absorbed. Serum lamivudine concentrations were maintained above 1 μM for ≥8 h of 24 h on the twice daily oral dosing schedule with doses of ≥2 mg/kg. The cerebrospinal fluid drug concentration measured 2 to 4 h after the dose was 12% (range, 0 to 46%) of the simultaneously measured serum drug concentration. A limited-sampling strategy was developed to estimate the area under the concentration-time curve for concentrations in serum at 2 and 6 h.  相似文献   
107.
Aplastic anaemia is both frequent and difficult to manage in patients with dyskeratosis congenita (DC). We recently treated a 23-year-old male for a year with granulocyte colony-stimulating factor (G-CSF) and erythropoietin (Ep), with an excellent neutrophil response, and a transient effect on haemoglobin levels. G-CSF alone or combined with other cytokines may provide at least a partial effect in pancytopenic patients with DC.  相似文献   
108.
Osseointegrated dental implants have now become an accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of 3i threaded and cylindrical implants. During a 5-year period, a total of 1969 3i endosseous implants were placed at 6 centers in the United States and 2 elsewhere in the edentulous and partially edentulous jaws of 653 consecutive patients ranging in age from 18 to 82 years. Of the total number of implants placed, 1341 were commercially pure titanium threaded implants and 628 were titanium plasma-sprayed implants with a cylindrical configuration. A total of 28 patients with 110 implants were lost to follow-up. Implants in these patients were considered neither a success nor a failure. Success was predicated on the osseointegration of each and every implant followed in this analysis rather than the persistence of prosthetic function. Confirmed bone anchorage was considered essential for success. A total of 625 patients with 1871 implants remain in the study with a follow-up period ranging from 6 to 60 months. A total of 93 implants (5.0% of the total implants followed) were considered as failures. A mean implant survival rate was 95.0% for both the threaded and the cylindrical implant was calculated. The success rate of threaded implants was 97.0% in the mandible and 93.8% in the maxilla. The success rate for the 3.3mm cylindrical implants was 96.0% in the mandible and 95.5% in the maxilla, and the success rate of 4.0mm diameter cylindrical implants was 95% in the mandible and 92.0% in the maxilla. Causes of failure consisted of loss of osseointegration 2.3%crestal bone loss requiring periodontal therapy after the first year of function 1.7% and mechanical problems associated with the prosthesis 0.9%. This retrospective analysis of the 3i endosseous implant system is comparable to previous reports on other implant systems in terms of implant survival and prosthesis stability. It is demonstrated that 3i implants are predictable and can provide lasting osseointegration leading to improvement of oral function if the recommended surgical and restorative protocol is followed.  相似文献   
109.
To study some of the factors relating to the care of mothers and newborns in an inner-city hospital, three sources of information were reviewed: an obstetric database including information on prenatal care and perinatal mortality, a database of all admissions to the hospital neonatal intensive care unit over the past 5 years, and a detailed questionnaire concerning attitudes and behaviors of recently delivered women. While analyses from these hospital-based data are not conclusive, the results add evidence for the following propositions: 1) Optimal prenatal care is infrequently obtained by mothers delivering at inner-city hospitals. Lack of prenatal care is clearly associated with increased perinatal mortality. While the need for prenatal care is appreciated by 98% of the mothers in this sample, the most frequent reasons why prenatal care is not obtained earlier or more frequently involve knowledge about and access to prenatal care. 2) Inner-city mothers, in general, manifest attitudes and behaviors that promote the welfare of their pregnancies and newborns. These attitudes and behaviors are in stark contrast to those that are frequently attributed to inner-city women by the media. 3) Acute perinatal medical and nursing care are perceived by many postpartum women as suboptimal, particularly in terms of the lack of respect shown to patients by nurses and doctors. 4) Improved acute obstetric and neonatal care improves perinatal morbidity and mortality of infants delivered at inner-city hospitals.  相似文献   
110.
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