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121.
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CM Heinicke M Goorsky S Moscov K Dudley J Gordon D Guthrie 《Canadian Metallurgical Quarterly》1998,68(4):534-541
Following up on previous work demonstrating that an intervention with at-risk mothers made a positive impact on the quality of mothers' partner support, responsiveness to the needs of the child, the child's expectation of being cared for, and child's response to a brief separation, the present paper examines whether quality of the mother's partner support mediated the impact of the intervention on these outcomes. 相似文献
123.
To estimate ethanol consumption by university students attending a student health facility, a biochemical marker of alcohol intake [whole blood associated acetaldehyde (WBAA)] was quantified by fluorimetric HPLC. Over a two year period we studied blood samples, coded by date and sex, from 645 females and 332 males, and compared the results to previously established reference ranges for teetotalers by sex. Men had higher absolute values for WBAA than women (9.9 versus 9.5 microM in the present study). However, significantly greater numbers of women (74%) than men (44%) had WBAA levels above the 99th percentile for teetotalers. Variations occurred during the academic year, with significant elevations occurring in the late fall and winter months. Testing of WBAA levels in a student health service may be important especially for women to facilitate counseling on the dangers of alcohol abuse. 相似文献
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The ratio of (Na+ +K+)-ATPase (EC 3.6.1.3.)isoforms with high and low affinity for cardiac glycosides was studied in heart preparations from neonatal, 3-month and 6-month old Wistar rats. Biphasic ouabain inhibition curves of (Na+ +K+)-ATPase activity indicated that the relative contribution of the high-affinity process decreased from 34% at 9 days to 23% at 3 months and to 10% at 6 months. Scatchard plots for [3H]ouabain binding were curvilinear and indicated that the relative contribution of the high-affinity sites (Kd = 0.1-0.25 microM) decreased by about one-half between 3 months (19-24%, N = 2) and 6 months (9-11%, N = 2). 相似文献
127.
Our objective was to examine the accuracy of diagnosis of HIV-associated central nervous system (CNS) toxoplasmosis. Individuals diagnosed with HIV-associated CNS toxoplasmosis and controls were ascertained from a population-based database. Diagnosis was confirmed by response to therapy or by histology. Symptoms, results of anti-Toxoplasma serology and use of Pneumocystis carinii pneumonia (PCP) prophylaxis were recorded. Central nervous system toxoplasmosis was confirmed in 54 (76%) of 75 patients. Reactive anti-Toxoplasma serology was associated with CNS toxoplasmosis (OR=20.4, 95% CI 3.1-175.8). Adjusting for CD4 and use of dapsone or aerosolized pentamidine, trimethoprim-sulphamethoxazole (TMP-SMX) for PCP prophylaxis was associated with lower likelihood of CNS toxoplasmosis (OR 0.3, 95% CI 0.1-0.7). Diagnosis of CNS toxoplasmosis is often incorrect. Another diagnosis is most likely in patients who are anti-Toxoplasma seronegative or who are receiving prophylactic TMP-SMX. 相似文献
128.
The yield of upper gastrointestinal endoscopy (esophago-gastroduodenoscopy; EGD) in human immunodeficiency virus (HIV)-infected patients based on presenting symptoms has not been well studied. We studied consecutive patients with documented HIV infection undergoing EGD at a large innercity hospital between August 1, 1990 and December 31, 1993; all had presenting symptoms and indications for EGD prospectively recorded at the time of EGD. All endoscopic abnormalities were routinely subjected to biopsy, and extensive histopathological evaluation was performed. EGD was considered helpful when the findings stimulated specific therapeutic intervention other than antifungal or antacid medications. The specific indications for EGD in 156 patients were as follows: esophageal symptoms, 102 patients (65%); abdominal pain, 18 (12%); upper gastrointestinal bleeding, 25 (16%); refractory nausea and vomiting, 11 (7%). Overall, pathologic findings were identified in 116 patients (74%): in refractory esophageal symptoms, 82%; upper gastrointestinal bleeding, 92%; abdominal pain, 39%; nausea and vomiting, 27%. EGD with biopsy identified a specifically treatable opportunistic disorder other than Candida in 80 patients (51%), including idiopathic esophageal ulcer (22%) or viral esophagitis and/or duodenitis (29%). EGD was not helpful in 22.3% of cases, those involving Candida (12.3%) and peptic ulcer disease (PUD)-related causes (10%). The mean CD4 count of patients with opportunistic pathologic findings (24/mm3, n = 79) was significantly lower than that of patients with PUD/gastroesophageal reflux disease (GERD) (167/mm3, n = 9) or negative EGDs (165/mm3, n = 35). Overall, the results of EGD influenced patient management in 78% of cases. We conclude that selective symptom-specific use of EGD, particularly in patients with esophageal symptoms refractory to antifungal therapy or gastrointestinal bleeding, usually identifies specifically treatable abnormalities, whereas EGD is less useful for the evaluation of abdominal pain or nausea and vomiting. 相似文献
129.
IM Robbins LL Cuiper CM Stein AJ Wood HB He R Parker BW Christman 《Canadian Metallurgical Quarterly》1998,85(2):731-737
Prostacyclin (or epoprostenol), an arachidonic acid metabolite, is an effective treatment for patients with primary pulmonary hypertension. Interruption of chronic prostacyclin infusion can result in recurrent symptoms of dyspnea and fatigue. The etiology of this phenomenon is unknown. We hypothesized that sympathoadrenal activation could lead to increased vascular tone after abrupt termination of the infusion. To evaluate this effect, we monitored six chronically instrumented, awake sheep during and after infusion of prostacyclin. Prostacyclin decreased mean arterial pressure (MAP) by 14% and increased cardiac output by 33%. After the infusion ceased, MAP rebounded 23% above baseline, and cardiac output decreased by 28% from peak values within 10 min. We were unable to demonstrate an increase in norepinephrine levels after cessation of prostacyclin, nor did alpha-adrenergic blockade affect postinfusion hemodynamics. However, plasma renin activity increased >10-fold at peak infusion and remained elevated for up to 2 h after discontinuation of prostacyclin. Coinfusion of the angiotensin II-receptor antagonist L-158,809 resulted in complete abrogation of the postcessation rise in MAP. We conclude that renin-angiotensin system activation is primarily responsible for systemic hypertension occurring after abrupt cessation of prostacyclin infusion in sheep and that angiotensin II receptor blockade prevents this response. Our data do not support a role for sympathetic nervous system activation in the systemic pressor response after prostacyclin infusion. 相似文献
130.
CG Salomon CL Kalbhen CM Dudiak MC Olson ME Flisak RC Flanigan 《Canadian Metallurgical Quarterly》1998,206(2):533-538
The effects of denervation of central noradrenergic system on the interpartner relationships of adult cats were examined in a predatory test in the competitive situation for paired animals. Direct administration of the noradrenaline neurotoxin, N-2-chloroethyl-N-ethyl-2-bromobenzylamine (DSP-4 12 microg) into the medial forebrain bundle (MFB) of submissive cats changed previously established dominant-submissive relationship. Biochemical analysis demonstrated a significant reduction of noradrenaline (NA) concentration in the hypothalamus (AH), amygdala (AM), hippocampus (HC), and frontal cortex (CTX), and elevation of NA content in the midbrain central gray matter (CG) in MFB-lesioned cats. Simultaneously, DSP-4-induced lesions exerted significant decrease of 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) content in AH, CG, HC and CTX, and increased GABA level in AH, CG, AM, and HC. These results suggest that a coincident decrease of NA metabolism and increase of GABA metabolism led to fear drive reduction. 相似文献