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41.
Summary Haemorrhage in regions remote from the site of following intracranial operations is rare, but they do occur. We performed supratentorial craniotomy on 639 patients between the time of introduction of computed tomography (CT) for clinical use in 1983 and June 1992; subarachnoid haemorrhage (SAH) in the posterior fossa occurred postoperatively in six of these cases. These included four patients with tumours in the sellar region, one with an arteriovenous malformation (AVM) and one who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. The ages of the six patients ranged from 17–72 years.Haemorrhage occurred on the day of operation in one case and was detected on CT examination on the day following surgery in the remaining five cases. Of three patients with disturbance of consciousness, two underwent suboccipital craniectomy for reduction of intracranial pressure, while one received barbiturate therapy and later underwent cerebrospinal fluid (CSF) shunt surgery. No special treatment was necessary for the remaining three patients with less serious lesions. Five of the six patients ultimately recovered their pre-operative neurological status apart from the primary diseases.Factors inducing such haemorrhages seem likely to include displacement of the cerebellum by reduced CSF pressure during and after operations, and stretching and tearing of the veins and venules in the sulci of the tentorial surface of the cerebellum. Consideration should therefore be given to the maintenance of an appropriate CSF pressure during operation; this is particularly important in elderly patients and those with an atrophied cerebral cortex.  相似文献   
42.
Background :
The BTA test is a latex agglutination assay for the qualitative detection in the urine of analytes that are associated with bladder tumor. We compared the results of the BTA test with those of voided urine cytology (VUC) in patients with bladder cancer.
Methods :
A multicenter trial was performed at 6 institutions. A total of 132 patients with histologically diagnosed bladder cancer were enrolled. Urine samples were split for BTA and VUC testing.
Results :
The sensitivities of the BTA test and VUC were 57.6% and 37.9%, respectively; this difference was significant ( P < 0.001). The BTA test had much higher sensitivity for small, solitary, superficial tumors than did VUC.
Conclusion :
The BTA test is simple to perform, gives rapid results, and is far more sensitive than VUC for detection of bladder cancer. The BTA test has the potential to become an additional tool for detecting bladder cancer.  相似文献   
43.
44.
Benazepril (CGS 14824A HCl) is a new prodrug type angiotensin converting enzyme (ACE) inhibitor. The active form is considered to be benazeprilat, a diacid hydrolyzed compound. Benazepril and benazeprilat inhibited the contraction induced by exposure with angiotensin I, not angiotensin II, in the isolated rabbit aorta. The ACE inhibiting activity of benazeprilat was 1000 times more potent than that of benazepril in this experiment. Benazepril as well as benazeprilat and captopril exerted little influence on norepinephrine, serotonin and high K(+)-induced contraction or bradykinin-induced relaxation in isolated blood vessel preparations, thus angiotensin II synthesis inhibition seemed to be the main cause for its vasodilation. Benazepril, unlike benazeprilat or captopril showed considerable influence on prostaglandin (PG)-induced responses at higher concentrations. The vasocontraction induced by PGF2 alpha was competitively antagonized at 10(-5)-10(-4) mol/l, while vascular responses induced by PGE1, PGE2 or PGI2 was inhibited at 3 x 10(-4) mol/l of benazepril. Although these influences on PGs might not contribute much to its vasodilatory mechanism, the action seemed interesting in relation to cough induction, a known side effect of ACE inhibitors in the market. Benazepril has two asymmetric carbon atoms, thus four optical isomers are possible, SS (benazepril), SR (CGP 14'829A), RS (CGP 42'454A), RR (CGP 42'456A). The SS configuration was the most potent for antagonizing angiotensin I-induced vasocontraction, which seemed to be the best fitted for the ACE molecule.  相似文献   
45.
Referenceless, or self-reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self-reference technique based on complex field estimation using 2D polynomials comprising complex-valued coefficients was proposed and optimized. Numerical simulations with a Gaussian-profiled phase distribution demonstrated that the ROI radius had to be 2.3-2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex-based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase-based method using the similar-order optimization strategy. The complex-based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase-based method yielded equivalent results with less polynomial orders.  相似文献   
46.
47.
We studied the outcome in 308 patients with acute myocardial infarction (MI) admitted to the coronary care unit of Kobe General Hospital. Short-term outcome (within 28 days after MI) and long-term outcome (more than 28 days) were examined with survival curves to find any relationship with a history of previous MI and with the site of the MI. In the short term, 38 of the 308 patients died of cardiac causes. The group with anterior MI tended to have higher mortality than the group of patients with inferior MI, and among patients without a previous MI, patients with anterior MI had significantly higher mortality (p = 0.01). In multivariate analysis by the logistic regression model, the site of the MI was found to be independently associated with the short-term outcome. In the long term, with a mean follow-up of 3.4 years, 23 of the 308 patients died of cardiac causes. Different sites of the MI did not result in different outcomes in patients with or without a previous MI. Of patients with anterior or inferior MI, those with a previous MI tended to have higher mortality, and of patients with an inferior MI, the difference was significant (p = 0.001). In multivariate analysis by the proportional hazards model, a history of MI was more predictive than the site of the MI. In conclusion, the site of the MI was associated more with the short-term outcome than with the long-term outcome, and a history of MI was associated more closely with the long-term outcome.  相似文献   
48.
The effect of ACTH and/or adrenalectomy on serotonin (5-HT)2 receptor binding sites was evaluated in the neocortex of rat forebrain. One day after the adrenalectomy or sham operation, ACTH (50 µg/day) was injected subcutaneously into adult male SD rats for 10 consecutive days. Saturation analysis showed that subchronic ACTH treatment significantly increased the Bmax values for3H-ketanserin binding without any change in the Kd values. Moreover, this ACTH-induced increase in the Bmax values was prevented by adrenalectomy. The concentrations of 5-HT and 5-hydroxyindole acetic acid (5-HIAA) measured by HPLC-ECD were not altered by these manipulations. Ten-day administration of corticosterone (20 and 50 mg/kg) also increased 5-HT2 receptor density in the neocortex of rat forebrain. 5-HT2 (and 5-HT1C) receptor agonist, (±)DOI-induced wet-dog shakes in ACTH and/or adrenalectomy-treated rats were also examined. Ten-day administration of ACTH enhanced (±)DOI-induced wet-dog shakes and this increase was prevented by adrenalectomy. These results indicate that subchronic adrenocorticotropinadrenal axis activation of rats increases both the number of 5-HT2 receptors in neocortex of forebrain and the wet-dog shake responses induced by (±)DOI.  相似文献   
49.
50.
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer.  相似文献   
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