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31.
Clinical features and laboratory data are presented for 100 patients with benign gastric ulceration and 150 patients with duodenal ulceration confirmed endoscopically in a district general hospital unit. Abdominal pain was the commonest indication for endoscopy, but one third of examinations were performed for acute gastrointestinal haemorrhage. Although the patients were selected by referral for endoscopy their clinical presentation, age, and sex distribution were similar to those reported in previous general surveys. There were no clinical features which clearly distinguished gastric from duodenal ulceration. However, of those with gastric ulceration younger patients more often had distal ulcers and presented with pain, while elderly subjects tended to have high lesser curve involvement and presented with haemorrhage. Moreover, all females presenting with haemorrhage were aged over 50 years, while 6% of males bleeding from gastric ulceration and 40% of males bleeding from duodenal ulceration were under this age. Anaemia when present, except in two premenopausal females, indicated either a recent acute gastrointestinal haemorrhage or a coexistent second diagnosis.  相似文献   
32.
The human allogeneic serum RM3 recognizes a lymphocyte structure inherited with the HLA chromosome. Population studies show several positive associations with antigens of the HLA-A and HLA-B series. Negative association have been found with antigens of the HLA-C series. Moreover the distribution of the RM3 factor is in Hardy-Weinberg equilibrium with that of the HLA-C alleles. However, serological investigations (namely the 'lysostrip' technique) bring evidence that RM3 serum does not appear to contain antibodies directed against any of the antigens of the HLA-A, B and C series. The study of a segregant family, showing a crossing over between the HLA-A and HLA-B loci, shows that the RM3 factor segregates on the side of the HLA-A locus. In conclusion, within the limits of the serological approach used, the present study presents evidence of a new serologically defined HLA locus, different from those so far described.  相似文献   
33.
The incorporation of free fatty acid into the placental and fetal liver lipids of rabbits was studied after fetal injections of albumin-bound 1-14C-palmitic acid. The fetuses were killed either 5--10 or 10--20 min after the injection. The placentas and livers were extracted for lipids and the specific activities of triglycerides (TG), phospholipids (PL), free fatty acids (FFA), monoglycerides (MG) and diglycerides (DG) measured. The lipids of the liver and placenta took up 17.0 and 3.6% of the dose, respectively, and of that liver TG accounted for 74% and the placental TG 34% of the label in each tissue. Most of the remaining counts were in the PL fraction with the rest more or less evely distributed between the FFA, DG and MG fractions. No activity was recorded in the cholesterol esters. The placental TG, PL, DG and MG specific activities reached the same level as that of the placental FFA, while in the liver these esters had higher specific activities (than the liver FFA). The liver TG, DG and PL had higher specific activities when compared with those of the placenta. The specific activity of the placental FFA was lower at 10--20 min than at 5--10 min; the opposite was seen for the placental TG. No time-related changes were seen in the liver lipids. It is concluded that (i) both placenta and fetal liver incorporate FFA into glycerides and PL; (ii) the liver incorporates FFA more rapidly and to a greater extent than the placenta; (iii) most of the FFA is incorporated into TG and to a lesser extent (PL; (iv) in both organs hydrolysis of PL or TG occurs. These results are discussed with reference to placental transport of FFA and fetal fat metabolism.  相似文献   
34.
The purpose of this study was to calculate the critical difference between two analytical measurements of serum fructosamine concentration in dogs. The critical difference can be used to judge whether the difference between two consecutive analytical results from the same animal is due to natural variation. Blood samples from 15 apparently clinically healthy beagle dogs were collected once a week for six consecutive weeks. The serum fructosamine concentration was measured by the reduction test with nitroblue tetrazolium and the critical difference was calculated from the component of variance for weeks within dogs (sigma2s) and the residual variance (sigma2e). The critical difference between two consecutive analytical results was 33.5 micromol/litre.  相似文献   
35.
Phosphomannose Isomerase (PMI) has been shown by genetic methods to be an essential enzyme in fungal cell wall biosynthesis. The PMI inhibitor AF14049 was discovered as an unanticipated side product from high-throughput library screening against the enzyme from C, albicans. Solid-phase synthetic methods were developed and a series of libraries and discrete analogs synthesized to explore SAR around AF14049.  相似文献   
36.
1. The cardiac anticholinergic effects of procainamide (1 mg kg(-1) min(-1)) and its N-acetylated metabolite (NAPA) at equimolar dose (1.16 mg kg(-1) min(-1)) were studied using in vivo experimental pharmacological and in vitro radioligand binding studies. 2. Procainamide and NAPA progressively reduced vagal stimulation-induced bradycardia in chloralose-anaesthetized dogs. As indicated by the ED50, the vagolytic activity of NAPA is 1.5-2.0 times weaker than that of procainamide. Both drugs increased heart rate, with lowering of mean blood pressure during the second part of procainamide infusion, but not during NAPA infusion. 3. Binding studies on rat heart membranes yielded Ki values that were 1.5 times higher for NAPA than for procainamide. 4. These results show that NAPA exerts a weaker cardiac vagolytic action than procainamide, which is probably linked to a lower ability to bind to cardiac muscarinic receptors.  相似文献   
37.
Isolated reaction centers (RCs) from Rhodobacter sphaeroides were found to bind Zn(II) stoichiometrically and reversibly in addition to the 1 equiv of non-heme Fe(II). Metal and EPR analyses confirm that Zn(II) is ligated to a binding site that is distinct from the Fe site. When Zn(II) is bound to this site, electron transfer between the quinones QA and QB (QA-QB --> QAQB-) is slowed and the room-temperature kinetics become distributed across the microsecond to millisecond time domain. This effect of metal binding on the kinetics is similar to the more global effect of cooling RCs to 2 degreesC in the absence of Zn(II). This suggests that Zn(II) binding alters localized protein motions that are necessary for rapid QA-QB --> QAQB- electron transfer. Inspection of the RC crystal structure suggests a cluster of histidine ligands located beneath the QB binding pocket as a potential binding site.  相似文献   
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The purpose of this study was to identify how women described and evaluated their labor and delivery experience and what factors were related to their responses. Sixty Lamaze-prepared, married multigravidae, aged 21 to 37 years, participated in this qualitative field study. Detailed, open-ended tape-recorded interviews were conducted on the postpartum unit of a community hospital or in the women's homes early during the postpartum period. Women evaluated their labor and delivery experience according to how well they perceived they had managed their own childbirth performance. Women who managed well viewed childbirth as positive, whereas women who had difficulty or managed poorly viewed it as both positive and negative. Women who managed well thought their own performance and the nature of labor and delivery (physical aspects) went well; women who had difficulty thought labor and delivery and the performance of others went well, but women who managed poorly had problems identifying anything that went well. There was overall agreement that the baby was the best part of the experience and that pain and pushing were the worst parts. Since women's evaluation of their labor and delivery experience may be related to the quality of their subsequent mothering, it is important to enhance their perceptions of their own performance, and thus their evaluation of the childbirth experience.  相似文献   
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