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181.
182.
W. S. L. Stebbings M. J. G. Farthing J. R. Puddefoot Elizabeth Anderson G. P. Vinson J. M. A. Northover R. F. M. Wood 《Journal of cancer research and clinical oncology》1988,114(2):208-211
Summary To evaluate the potential effect of androgens on the development and growth of human colorectal adenomas, the prevalence and concentration of cytosolic androgen receptors (AR) were analysed in 26 adenomas and 19 samples of normal colonic mucosa by a hybrid ligand receptor-binding assay. AR were detected in 7 of the adenomas (26.9%), and in 6 of the normal mucosa samples (31.6%). In the adenomas, AR levels demonstrated were low, ranging from 6 to 31 fmol/mg cytosol protein, and dissociation constants (Kds) ranged from 0.17–2.7x10-9
M. Of 13 adenomas excised from men, 6 (46%) had positive receptor activity, whereas only 1 of 13 (7.7%) from women was positive (P=0.03, Fisher's exact test). There was no correlation between AR titre and patient age, or between adenoma size and histological type or degree of dysplasia. In normal mucosa, AR levels ranged from 7 to 33 fmol/mg and Kds ranges from 0.24–3.1x10-9
M. There was no significant difference between either AR prevalence or levels in the adenomas and normal mucosa. The sex difference was exclusive to the adenoma. Endogenous androgen may play a role in adenoma development early in the promotional process. 相似文献
183.
A mechanistic QSAR study on N-nitrosamines (NA) was performed with the aid of the semiempirical MINDO/3 method. Both the chemical reactivity and the transport in biological medium were taken into account. The parent NA molecules and their first reaction intermediates in the metabolic activation pathway were examined for possible determinants of the relative carcinogenic potency. The correlations found support the previous suggestions concerning the metabolic C alpha radical hydroxylation of NA. The role of transport properties in the early stage of NA biotransformation was also demonstrated. 相似文献
184.
Using indirect immunohistochemistry and an antiserum raised against rat corticotrophin-releasing factor (CRF) we have outlined an asymmetric network of cells and varicose fibers in sheep adrenal cortex. This network was not associated with the larger splanchnic nerves, but was occasionally found in small bundles or with blood vessels; in most instances fibers were found weaving independently through cortical parenchyma. A plexus of fibers was found in the zona reticularis, with a few fibers ramifying into adjacent medulla. Uni or bipolar cells were found throughout the cortex, with the greatest frequency at the corticomedullary junction; a multipolar-type cell was also found in this area. Staining of varicose structures and most cells was abolished by incubation with excess rat CRF 1-41, but not by ovine CRF or a range of other peptides. Though the immunoreactive species has not as yet been identified, it may thus share homology with sequences present in rat but not ovine CRF. 相似文献
185.
S Hummel J Slapke 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1988,43(12):319-323
In any case of acute bronchoconstriction the possibility of an adverse reaction to a drug should be considered. In many of such side reactions no allergic mechanism can be detected. Therefore, they are included into the category of pseudoallergic reactions (PAR). The clinically most important form of drug-induced bronchial asthma, analgesics asthma, belongs to this PAR group. A further risk for asthmatics are intravenous applications of contrast-media for roentgenography which in about 15% induce a severe, sometimes life-threatening pseudo-allergic adverse reaction. In asthmatics, the application of any beta-receptor blocking agents and also the use of parasympathicotonic eye drops for treatment of glaucoma are contraindicated. Paradoxical bronchial constriction following application of antiasthmatics are preponderantly caused by locally irritative actions, less frequently by genuine allergic phenomena or additive intolerance. The most reliable prophylaxis against drug-induced bronchial asthma consists in strong avoidance of all derivatives possibly capable to trigger any intolerance. A respective warning should entered into the emergency passport. 相似文献
186.
The role of hypertension and antihypertensive drugs in cardiovascular complications was evaluated in 380 elderly people living in the Tokyo Metropolitan Gerontology Center. The subjects were classified into four groups according to the presence or absence of hypertension and their antihypertensive treatment, and followed up prospectively for 5 years from 1979 to 1984. The average age of each group was 74 to 76 years. Cerebrovascular disease was observed in 19.3% of male hypertensives and 10.1% of male normotensives (p = 0.078). The drug treated group revealed no cerebral hemorrhage and less cerebral infarction. This tendency was not observed in females. Ischemic heart disease was prevalent in the drug treated group (10.9% vs 4.5%, p = 0.023) irrespective of blood pressure level. Risk factors such as body mass index, skinfold thickness, serum cholesterol, albumin, creatinine, blood urea nitrogen and uric acid at entry were elevated in the drug treated group. Diuretics were used in 92% of the drug treated group; in 53% as monotherapy and in 39% as combination therapy with other antihypertensive agents. The metabolic effect of diuretics may increase the incidence of ischemic heart disease in the elderly. We might conclude that hypertension in the aged accelerates cerebrovascular complications, and that antihypertensive treatment is effective even in this group. However, the wide use of diuretics could increase the incidence of ischemic heart disease. Careful selection of antihypertensive drugs as well as dose adjustment are needed in the treatment of elderly hypertensives. 相似文献
187.
188.
189.
Our experience with pulmonary valve insertion during reoperation for residual lesions after initial open repair of tetralogy of Fallot in 15 patients is reported. Preoperatively, 14 patients were in moderate to severe congestive heart failure, and all 15 had decreased right ventricular (RV) function at cardiac catheterization. All 15 patients had pulmonary insufficiency but not as an isolated finding. The most common residual lesions encountered were ventricular septal defect in 9, tricuspid insufficiency in 11, and peripheral pulmonary arterial stenosis in 6. Tissue valves were inserted in all patients. Mean peak RV-left ventricular pressure ratio measured in the operating room decreased from 0.61 +/- 0.10 (+/- the standard deviation) to 0.47 +/- 0.17 (p less than 0.05). There were no operative deaths. At follow-up (mean, 33 months), all but 1 patient were in New York Heart Association Class I or II. Pulmonary valve insertion should be considered during reoperation for tetralogy of Fallot when pulmonary insufficiency and RV failure are present. 相似文献
190.
APACHE II score and abdominal sepsis. A prospective study 总被引:7,自引:0,他引:7
J M Bohnen R A Mustard S E Oxholm B D Schouten 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(2):225-229
Therapeutic trials for intra-abdominal sepsis require pretreatment stratification; physiologic scoring has been recently proposed for this purpose. We have prospectively tested the validity of one such scoring system, namely, the Acute Physiology and Chronic Health Evaluation (APACHE II). As part of a larger database, we correlated APACHE II scores with mortality in 100 patients hospitalized for generalized peritonitis or abdominal abscess. Use of steroids was recorded because of our suspicion that steroids increase mortality but blunt the physiologic response to sepsis. Thirty-one patients died, including 12 of 19 patients receiving steroids. Stepwise discriminant analysis revealed that the APACHE II score and steroid use were each independently associated with the rate of mortality. We report a prospective validation of pretreatment APACHE II scoring in abdominal sepsis. Steroid use is an independent risk factor. 相似文献