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71.
The relationship between testosterone levels and cognitive ability patterns.   总被引:11,自引:0,他引:11  
The cognitive performance of normal men and women was studied, grouped according to whether the subjects had relatively high or low salivary testosterone (T) concentrations. Men with lower T performed better than other groups on measures of spatial/mathematical ability, tasks at which men normally excel. Women with high T scored higher than low-T women on these same measures. T concentrations did not relate significantly to scores on tests that usually favor women or that do not typically show a sex difference. These results support suggestions of a nonlinear relationship between T concentrations and spatial ability, and demonstrate some task specificity in this respect.  相似文献   
72.
73.
OBJECTIVE: To investigate the possibility in rats that ONO-5046 Na, a new recombinant inhibitor of neutrophil elastase, can reduce hepatic metastases induced by ischaemia-reperfusion. DESIGN: Laboratory experimental study. SETTING: Research laboratory, Japan. SUBJECTS: Male Fischer rats. INTERVENTIONS: Rats underwent 60 min of 70% partial hepatic ischaemia, after which rat colon adenocarcinoma cells (RCN-H4) were injected into the spleen. The animals were divided into two test groups and a control group. One group was given ONO-5046 Na intravenously at 10 mg/kg/hour. A second group was given a saline solution for the same period, while the controls were not made ischaemic. MAIN OUTCOME MEASURES: Three weeks after inoculation, the number of tumour nodules on the liver surface was counted. The anti-cancer effect of ONO-5046 Na was measured by monotetrazolium assay. RESULTS: Hepatic ischaemia-reperfusion increased the number of liver metastases of RCN-H4 in both clamped and unclamped hepatic lobes. ONO-5046 Na significantly inhibited this in unclamped lobes, but had no anti-cancer effect. CONCLUSION: Neutrophil elastase may have an important role in increasing haematogenous liver metastases by ischaemia-reperfusion, particularly in unclamped lobes.  相似文献   
74.
Ca(++)-dependent monoclonal antibody specific to gamma-carboxyglutamic acid (Gla) domain of protein C was produced. It did not cross-react to the other vitamin K-dependent plasma proteins but to protein C of the other species. Using this monoclonal antibody, PC01, rabbit (170 micrograms), rat (60 micrograms) and mouse (40 micrograms) protein Cs were isolated from 100 ml of their plasma by affinity chromatography. All of these protein Cs were two chain form linked by disulfide bond as well as human protein C and activated by thrombin-thrombomodulin complex. Rat and mouse protein Cs showed similar characters to human protein C. On the other hand rabbit protein C had different M(r) of heavy and light chains and showed lower anticoagulant activity compared with human protein C.  相似文献   
75.
The serum triglyceride concentration (TG) tested in health checks after meals cannot properly sort out hypertriglyceridemia with reference to the upper normal limit of fasting TG (150 mg/dl) set by the Japan Arteriosclerosis Society, because TG goes up considerably after a meal. In our survey of a large number of health check examinees (free of abnormal biochemical data other than TG and diseases under medical treatment), the mean (M) of fasting TG + 2 standard deviations (SD) was close to 150 mg/dl. When the screening level was set at M + 2SD for each time span after a meal, the ratio of the screened was distributed between 19.9 and 21.8%, which was close to 23.5%, the ratio of the screened on fasting. Accordingly, the nearest round number ending with zero for the first digit is suggested to be of practical use for the screening level of after-meal TG. The average TG in females was definitely lower than that of males, though proportionately increasing with age. The ratio of the screened among females aged between 20 and 49 was 5.3% on fasting and 3.2-5.8% for after-meal time spans, and that of the screened aged in their fifties was 11.3% and 8.2-12.9% respectively.  相似文献   
76.
Growth of the patients with hematological malignancies, aplastic anemia, Fanconi's anemia, and Wiscott-Aldrich syndrome who had been treated with bone marrow transplantation (BMT) was studied. Fourteen out of 21 patients showed suppression of linear growth after BMT. Recovery of the growth velocity after 1-2 years tended to occur if BMT was performed at younger age. Six of eight patients with chronic graft-versus-host-disease (CGVHD) had impaired growth after BMT, whereas eight of 13 (61%) without CGVHD did. Provocative tests for growth hormone (GH) performed 5-72 months after BMT revealed three boys who showed poor response to more than two different stimuli. Two of these three boys had prolonged suppression of growth. Neither the age at BMT, difference in disease, nor presence of posttransplant growth retardation gave significant difference in the response of GH to provocative tests. It was concluded that approximately two-thirds of marrow-grafted children experienced transient decrease in growth velocity after BMT.  相似文献   
77.
A Japanese woman, aged 42, was admitted because of paroxysmal attacks consisting of paresthesia of the left face, tremor in the right hand, epigastric pain and urinary incontinence. A year prior to the admission, she noticed some difficulty in writing, dysarthria and unsteadiness of walking. These symptoms had been persistent since then. At the end of March, 1991, these symptoms rapidly worsened, and she fell down frequently. She also experienced pain behind both eyes, numbness in her left fingers and toe, urinary frequency and the above-mentioned attacks. Neurological examination disclosed bilateral internuclear ophthalmoplegia and upbeating nystagmus on upward gaze, titubation in the head, scanning speech, dysmetria in all limbs, exaggerated reflexes in jaw and both legs, bilateral extensor plantar reflexes and ankle clonus. SEP showed delayed cortical response with stimulation of the median nerves bilaterally and of the right posterior tibial nerve. P40 was absent with the left posterior tibial nerve stimulation. VEP was normal. T2-weighted image of MRI showed multiple high intensity areas located around the third ventricle, crus cerebri and the right upper part of the pons. The diagnosis of multiple sclerosis was made. Each paroxysmal attack started with numbness in the left face and burning sensation in the neck. Almost simultaneously tremor in the right hand began. The surface EMG showed the rhythmic contractions in the dorsal hand muscles and wrist extensors at a frequency of 6-7 Hz, and sometimes it revealed synchronized contractions of finger flexors and the dorsal hand muscles. A few seconds later she felt painful sensation in the epigastric region, and the tremor gradually increased in its intensity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
78.
Severe hypertension developed in a fifty-five year-old woman after surgical removal of a retroperitoneal tumor, when the renal artery was injured. Renal arteriography after the surgery demonstrated a segmental infarction of the right kidney. A close relationship between activation of the renin-angiotensin system and the development of severe hypertension was observed. Satisfactory control of blood pressure concomitant with reduction of plasma renin activity was achieved by a combination of an angiotensin-converting anzyme inhibitor, beta-blocking agent, and calcium-entry blocker. The mechanism of activation of the renin-angiotensin system in renal infarction is discussed.  相似文献   
79.
Species and sex differences of aflatoxin B1 (AFB1)-induced glutathione S-transferase placental form (GST-P) positive single hepatocytes have been investigated 48 h after an intraperitoneal injection of AFB1 to young male and female Fischer rats (2 mg AFB1/kg body wt) and male Syrian golden hamsters (6 mg AFB1/kg body wt). The presence of GST-P positive hepatocytes was examined by the immunohistochemical method. Male rats formed three times as many AFB1-induced GST-P positive hepatocytes as females. Pretreatment of both male and female rats with an inhibitor of GSH synthesis, buthionine sulfoximine (BSO) (4 mmol/kg body wt), 2 h and 4 h before AFB1 injection increased AFB1-induced GST-P positive hepatocytes by about 120% above the controls. Male hamsters formed several-fold less AFB1-induced GST-P positive hepatocytes than male rats. Pretreatment with BSO did not increase AFB1-induced GST-P positive hepatocytes in hamsters even though it produced an increase in hepatic necrosis. It appears that GSH and GSH S-transferases play an important role in modulating hepatic AFB1-DNA binding and AFB1-induced GST-P positive hepatocytes in rats and hamsters.  相似文献   
80.
Changes in cardiac myosin heavy chain (MHC) gene expression and isozyme transitions have been shown to be caused by developmental changes, hemodynamic overload, or the activity of various hormones. In this study, to examine whether caffeine, which has teratogenic effects on the fetal cardiovascular system, causes the distribution of cardiac MHC phenotype and, if so, to evaluate the mechanisms of the distribution of cardiac MHC phenotype by caffeine, we examined the effects of caffeine, theophylline, and cAMP on the cardiac MHC isoform transitions at the gene and protein levels using hypothyroid adult rats. Furthermore, we examined the expression of alpha- and beta-MHC gene in cardiac muscles of fetuses whose dams had received caffeine. The results showed that caffeine, theophylline, and cAMP caused accumulations of alpha-MHC mRNA and MHC isozyme V1. Furthermore, in the fetal hearts, it was recognized that caffeine induced an accumulation of alpha-MHC gene expression, as was also seen in the dams. However, this effect of caffeine on the heart was stronger in the fetus than in the dam. Intracellular cAMP concentration was increased by the administration of caffeine, theophylline, or cAMP, and the levels showed a positive correlation with those of alpha-MHC mRNA. These results suggest that the induction of alpha-MHC mRNA expression by the administration of caffeine may be induced by an increase in intracellular cAMP concentration.  相似文献   
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