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991.
The anticholinergic effect of atropine, imipramine, clomipramine and metapramine was evaluated on oxotremorine induced trembling in the mouse as well as on contractions of the isolated guinea pig ileum induced by electrical stimulation of the mesenteric plexus. The ED 50 and IC 50 which expressed the anticholinergic activity of these substances, were found to be identifically distributed for both methods. Activity, in decreasing order was found to be: atropine much greater than imipramine greater than clomipramine greater than metapramine. There was a good correlation between results from the two methods (r = 0.97). The method using the stimulated guinea pig ileum would therefore seem suitable for characterisation of potential anticholinergic activity of a molecule.  相似文献   
992.
993.
In a single patient suffering from a major depressive episode with melancholia (DSM-III), both severe psychomotor symptoms, such as stupor and mutism, and mood disturbances could be abolished completely and promptly by administration of the benzodiazepine lorazepam. Remission of symptoms was entirely and immediately reversed by the benzodiazepine antagonist Ro 15-1788. These drug effects were constantly reproducible. Possible mechanisms of action and the influence of GABAergic neurotransmission on affective and psychomotor state are discussed.  相似文献   
994.
C P Caygill  M J Hill  C N Hall  J S Kirkham    T C Northfield 《Gut》1987,28(8):924-928
Of 5018 patients who had undergone gastric surgery at St James Hospital, Balham, at least 25 years ago, death certificates have been received for 2768, whilst 1746 patients are still alive and are flagged (Office of Populations, Censuses and Surveys (OPCS) will notify us of their death and its cause) and only 504 could not be traced. Mortality from cancers of various organs has been determined using a 'years at risk' calculation in five year bands. There was no increase in mortality risk from any cancers during the first 15 postoperative years, but from 20 years after operation there was a significant excess risk not only of cancer of the stomach (4.5-fold), but also of the large bowel (1.6-fold), bronchus (3.9-fold), pancreas (4.0-fold), biliary tract (9.1-fold), oesophagus (2.3-fold), bladder (2.4-fold), breast (4.0-fold), and cancer of all sites (3.3-fold). These findings are consistent with the production in the operated-upon stomach of circulating carcinogens with a 20 year latency period.  相似文献   
995.
In 151 years since first described, there have been 112 reported cases of hernia through the foramen of Winslow (HFW). All thus far have described HFW as a primary entity. The case reported appears to be unique with HFW as a surgical complication. HFW is the least common of internal hernias. The primary symptom is pain referred from the herniated organ and the hepatoduodenal ligament. An interesting sign is that the patient is found curled up or stooped over for pain relief. Anatomic factors implicated in HFW are an enlarged epiploic foramen, a floppy cecum and ascending colon, or abnormal length of small bowel mesentery. Tension on these structures causes pain with the torso extended. Distention of bowel in the lesser sac mimics gastric obstruction. Organs herniated are: small bowel (63%); cecum, ascending colon, and terminal ileum (30%); and transverse colon (7%). Of 25 cases reported since 1966, cecal herniation comprised two-thirds. The diagnosis may be made radiologically and the treatment is surgical. The case and a review of the literature are presented with attention to the anatomy. Also provided are the signs and symptoms of this interesting and perplexing diagnosis.  相似文献   
996.
In order to determine if serial, noninvasive evaluation of polytetrafluoroethylene (PTFE) vascular access grafts could identify a subgroup of patients at risk for thrombosis, the authors studied flow characteristics, using duplex ultrasonic scanning, in 18 hemodialysis patients with forearm loop grafts. On average, five examinations were performed per patient over the 10-month study period. Seven episodes of thrombosis occurred in six patients. The mean Doppler flow in grafts that subsequently thrombosed was significantly lower than in those that did not (544 +/- 218 ml/min versus 843 +/- 391 ml/min, p less than 0.001). The interval from last examination to thrombosis ranged from 13 to 58 days. At a defined cut-off flow of 450 ml/min, this test yielded a sensitivity of 83% and a specificity of 75% for episodes of thrombosis occurring within 2 to 6 weeks. The authors conclude that episodes of thrombosis in PTFE arm loop grafts are usually preceded by significantly lower Doppler-measured flow than grafts that do not thrombose and that it may be possible, by this means, to identify grafts at risk.  相似文献   
997.
Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality.  相似文献   
998.
Clinical and biological data were evaluated using Desu univariate analyses or Cox multivariate analyses in a series of 1,777 chronic lymphocytic leukemia (CLL) patients from an Italian Cooperative Group. In univariate analyses, age and sex of patients, presence of bone marrow (BM; greater than or equal to 50%), and peripheral blood (PB; greater than or equal to 60,000/microL) lymphocytosis, anemia (hemoglobin [Hb] less than 11 g/dL), thrombocytopenia (less than 100,000/microL), direct Coombs' test positivity, hepatomegaly, splenomegaly, and extent of lymph node involvement were shown to be of significant prognostic value. Multivariate analyses, through a stepwise procedure, showed that the most important prognostic variables are Hb, hepatomegaly, lymph node involvement, PB lymphocytosis, and age and sex of patients. Further covariates would produce an improvement having a nonsignificant P value. Based on the results of multivariate analyses, a four-step staging using the significant variables of the Cox model is proposed.  相似文献   
999.
1000.
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