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61.
OBJECTIVE--To present a more realistic assessment of surgical workload than that provided by a case count. DESIGN--Prospective study of all the operative procedures performed in one year, classified according to the British United Provident Association''s schedule of procedures and scored by the "intermediate equivalent" value (taking the recommended fee value of an intermediate operation as 1.0) compared with the number of operations performed. SETTING--General surgical unit of Taunton and Somerset Hospital, comparing four consultant surgeons and their teams. PATIENTS--Inpatients and day patients admitted under the care of general surgeons during 1989. MAIN OUTCOME MEASURE--Difference between the apparent workload represented by simple case counting (caseload) and the actual workload represented by calculation of the total "intermediate equivalent" value. RESULTS--The workload assessed in terms of intermediate equivalent values was greater than that suggested by case counting for complex operations (12% v 4%), operations at the district hospital (82% v 74%), and operations performed by consultants (53% v 35%) and was lower for minor operations (20% v 42%), operations at the community hospitals (18% v 26%), and operations performed by surgeons in training grades and clinical assistants (47% v 66%). CONCLUSIONS--The use of the intermediate equivalent values as an indicator of complexity allows a more realistic assessment of the operative workload than a simple case count of the number of different operations and is recommended for comparing workload in different hospitals and departments.  相似文献   
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Platelet-activating factor in the rabbit uterus during early pregnancy   总被引:3,自引:0,他引:3  
Platelet-activating factor (PAF) concentrations were low in the non-pregnant, oestrous uterus (mean +/- s.e.m.: 2.2 +/- 1.2 pmol/g, n = 3). However, uterine PAF increased dramatically during pregnancy to a maximum of 37.8 +/- 4.90 pmol/g (n = 7) on Day 5. By Day 7, PAF concentrations in the uteri of pregnant rabbits had returned to levels similar to those found at oestrus. In contrast, uterine PAF in pseudopregnant rabbits peaked at 30.6 +/- 2.8 pmol/g (n = 8) on Day 4, declined to 20.5 +/- 2.4 pmol/g (n = 8) on Day 5 and then remained at that concentration through Day 7. Uterine PAF co-migrated with synthetic PAF (1-O-hexadecyl-2-acetyl-sn-glycero-phosphocholine) in both thin-layer and normal-phase high-performance liquid chromatography. PAF activity in the uterus during pregnancy and pseudopregnancy was found almost exclusively in the endometrium; little or no PAF was found in myometrium, uterine flushings or blastocysts. While no PAF was detected in blastocysts on Days 5 and 6 of pregnancy, the presence of the embryo appears to modulate biosynthesis and/or degradation of PAF by the uterus, since PAF decreased significantly in uterine tissue apposed to the implanting embryo (but not in similar areas between such attachment sites). Increased concentrations of PAF in the preimplantation rabbit uterus followed by a dramatic decrease on the day of blastocyst attachment suggest that this potent inflammatory autacoid may play a vital role in implantation.  相似文献   
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The formation of mutagens and carcinogens of the 2-amino-3-methylimidazo[4,5-f]quinoline and -quinoxaline type, formed during the frying or broiling of meats and in liquid-reflux laboratory models, was inhibited by L-tryptophan in a dose-dependent fashion. Addition of 75 mg (1.04 mg/cm2 surface area) of L-tryptophan per side in a sauce to ground beef patties prior to cooking significantly blocked the formation of mutagens observed in control patties treated identically with sauce but without L-tryptophan. The sauce itself did not have a significant inhibitory effect. When a mixture of 35 mM glucose, 70 mM glycine, and 70 mM creatinine in diethylene glycol-water (95:5) was heated in a liquid-reflux model for 2 h at 150 degrees C, the addition of 1.75-105 mM L-tryptophan gave a dose-related inhibition of mutagen formation, that reached 100% inhibition with 105 mM L-tryptophan.  相似文献   
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Agrobacterium radiobacter NCIB 11883 was grown in ammonia-limited continuous culture at low dilution rate with glucose as the carbon source. Under these conditions the organism produced an extracellular succinoglucan polysaccharide and transported glucose using the same periplasmic glucose-binding proteins (GBP1 and GBP2) as during glucose-limited growth. Transition from glucose- to ammonia-limited growth was accompanied by a very rapid decrease in glucose uptake capacity, whereas the glucose-binding proteins were diluted out much more slowly (t1/2 approximately 1 h and 14 h respectively). Although the rate of glucose uptake and the concentrations of GBP1 and GBP2 were much lower during ammonia limitation, the activities of enzymes involved in the early stages of glucose metabolism and in the production of succinoglucan precursors were essentially unchanged. Glucose transport was also investigated in two new strains of A. radiobacter which had been isolated following prolonged growth under glucose limitation. Glucose uptake by strain AR18 was significantly less repressed during ammonia limitation compared with either the original parent strain or strain AR9, and this was reflected both in its relatively high concentration of GBP1 and in its significantly higher rate of succinoglucan synthesis. Flux control analysis using 6-chloro-6-deoxy-D-glucose as an inhibitor of glucose transport showed that the latter was a major kinetic control point for succinoglucan production. It is concluded that glucose uptake by A. radiobacter, particularly via the GBP1-dependent system, is only moderately repressed during ammonia-limited growth and that the organism avoids the potentially deleterious effects of accumulating excess glucose by converting the surplus into succinoglucan.  相似文献   
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Seven polymorphic loci mapping to human chromosomal region 11q22-qter   总被引:11,自引:0,他引:11  
Seven polymorphic loci that map to human chromosomal region 11q22-qter are revealed by DNA probes isolated from a chromosome-specific phage library constructed from a human X mouse somatic cell hybrid that has retained an 11q;16q translocation as the only human DNA. Three probes, each of which reveals a two-allele polymorphism, and four probes, each of which detects two linked RFLPs, have been characterized. Using a somatic cell hybrid mapping panel that divides 11q into four discrete sections, the seven clones have been localized to specific chromosomal regions. Localization of one of the clones has been confirmed and refined by in situ hybridization.  相似文献   
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To evaluate ras-mediated signal transduction, an alkaline phosphatase gene (SEAP) was placed under the control of the ras-inducible phorbol ester response element (TRE) in murine fibroblasts (TRE-SEAP cells). The Kirsten ras gene was placed under the control of the glucocorticoid-inducible mouse mammary tumor virus promoter and introduced into the TRE-SEAP cells. Dexamethasone increased ras expression in the TRE-SEAP cells carrying the Kirsten ras gene and stimulated SEAP activity 25-fold. Lavostatin blocked dexamethasone induction of SEAP activity (50% inhibitory concentration, 0.5 microM) but did not affect phorbol ester-induced SEAP activity in the same cells. Lovastatin also did not block forskolin induction of SEAP activity in cells expressing SEAP under the control of the cyclic AMP response element.  相似文献   
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