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81.
OBJECTIVE: To extend and test hypotheses linking positive and negative symptoms to selective aspects of verbal memory in schizophrenia. BACKGROUND: Verbal memory includes the ability to discriminate and prevent the intrusion of irrelevant information into recall and recognition. This ability has been proposed as a cognitive process that differentially mediates positive and negative symptoms. METHOD: Four error discrimination and 1 general recall memory index from the California Verbal Learning Test as well as general ability (IQ) and sex were used as predictors of symptom ratings in 55 schizophrenia patients within a regression framework. RESULTS: Intrusion errors during free recall contributed significantly to the prediction equation for negative symptoms (Brief Psychiatric Rating Scale). In contrast, positive symptoms and general psychopathology were not predicted by any of the discrimination indices. However, general recall memory (California Verbal Learning Test total words trials 1-5) contributed significantly to the prediction of general psychopathology and marginally to the prediction of negative symptoms. CONCLUSIONS: Impaired recall memory predicts levels of nonspecific psychopathology in schizophrenia. Negative symptoms associate with low intrusion error rates, but there is no evidence of an association between elevated errors and positive symptoms. 相似文献
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Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient. 相似文献
84.
The role of alpha- and beta-adrenoceptor subtypes in mediating the effects of catecholamines on fasting glucose and insulin concentrations in the rat. 总被引:2,自引:1,他引:1 下载免费PDF全文
1. The role of alpha- and beta-adrenoceptor subtypes in the regulation of plasma glucose and immunoreactive insulin (IRI) levels has been investigated in normal conscious fasted rats by employing selective agonists and antagonists. 2. Adrenaline (0.2 mg kg-1)-induced hyperglycaemia was abolished by the selective alpha 2-adrenoceptor antagonist idazoxan (1.0 mg kg-1), unaltered by non-selective beta-adrenoceptor blockade (propranolol, 1.0 mg kg-1) and potentiated by the selective alpha 1-adrenoceptor antagonist prazosin (0.3 mg kg-1). Adrenaline increased plasma IRI levels in the presence of idazoxan but not in the presence of either prazosin or propranolol. 3. The selective alpha 2-adrenoceptor agonists UK 14304 (0.1 and 0.3 mg kg-1) and BHT-920 (0.2 and 0.5 mg kg-1) elicited dose-dependent hyperglycaemic responses, but did not alter plasma IRI levels. UK 14304 (0.1 mg kg-1)-evoked hyperglycaemia was blocked by idazoxan but not by prazosin. 4. The selective alpha 1-adrenoceptor agonists methoxamine (0.3 mg kg-1) and phenylephrine (0.3 mg kg-1) failed to modify either plasma glucose or IRI levels. 5. Isoprenaline (0.2 mg kg-1) elicited hyperglycaemic and insulinotropic responses which were attenuated by propranolol (1.0 mg kg-1) and the selective beta 2-adrenoceptor antagonist ICI 118551 (1.0 mg kg-1), but not by the beta 1-selective antagonists atenolol (1.0 mg kg-1) and betaxolol (1.0 mg kg-1). 6. None of the antagonists per se affected basal plasma glucose or IRI concentrations, except prazosin (1.0 mg kg-1).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
85.
Advanced primary breast cancer: assessment at mammography of response to induction chemotherapy 总被引:2,自引:0,他引:2
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer. 相似文献
86.
Jan Lycke Bo Svennerholm Anders Svenningsson Walter Muranyi Rolf M. Flügel Oluf Andersen 《Journal of neurology》1994,241(4):204-209
The role of human spumaretrovirus (HSRV) infections in the pathogenesis of multiple sclerosis (MS) was investigated with recombinant HSRV env-specific enzyme-linked immunosorbent assay. The presence of HSRV antibodies was determined in pairs of serum and cerebrospinal fluid (CSF) samples from 60 MS patients. In 7 of these patients serial serum and CSF samples were obtained in relation to the clinical activity of the disease during a period of 2 years. No increased antibody reactivity was demonstrable in the MS population compared with 14 aseptic meningitis patients, 50 blood donors and 16 healthy controls. Slightly elevated levels of antibodies were demonstrable in serum and/or CSF in 4 MS patients but also in 1 patient with aseptic meningitis, 1 blood donor and 1 child. No marked serum or CSF HSRV antibody fluctuation was observed in the MS patients followed longitudinally. Thus, this study does not support the involvement of HSRV in the pathogenesis of MS. 相似文献
87.
The relationship of cancer incidence to terrestrial radiation and population density was investigated. Cancer incidence was obtained using 40 years of age-standardized data from the Connecticut Tumor Registry, and environmental radiation was estimated using data from an airborne gamma radiation survey of the entire state. These variables were examined ecologically, using the 169 towns of the state as the analytic units in a weighted regression analysis. The study design involves a large population base in a state having relatively high terrestrial radiation exposure levels overall and reasonable variation in exposure between towns. For all cancer combined, only one of the eight sex-specific analyses by decade yielded a significant radiation regression coefficient, and this was negative. In the sex- and site-specific analyses, almost all the coefficients for radiation were not significantly different from zero. In contrast, significant positive relationships of cancer incidence with population density were found for all cancer, for cancer of the lung for both sexes, for stomach, colonic, and prostatic cancer for males, and for lymphomas, thyroid, breast, and ovarian cancer for females. Both the radiation and population density relationships were adjusted for socioeconomic status. Socioeconomic status was significantly negatively associated with stomach and lung cancer in males and with cervical cancer in females; it was also positively associated with lymphomas and breast cancer in females. A power calculation revealed that, despite the relatively large size of this study, there was only a small probability of detecting a radiation effect of the strength anticipated from previous estimates. 相似文献
88.
89.
Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. 总被引:21,自引:0,他引:21
Heike A Bischoff Hannes B St?helin Walter Dick Regula Akos Margrith Knecht Christian Salis Matthias Nebiker Robert Theiler Michael Pfeifer Bettina Begerow Robert A Lew Martin Conzelmann 《Journal of bone and mineral research》2003,18(2):343-351
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function. 相似文献
90.