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81.
Sara Lucena Belsy Guerrero Ana M Salazar Amparo Gil Carmen L Arocha-Pi?ango 《Blood coagulation & fibrinolysis》2006,17(6):427-435
Lonomia achelous is a caterpillar distributed in southern Venezuela and in northern Brazil that causes an acute hemorrhagic syndrome in people who have contact with its bristles. The effect of the crude hemolymph and its chromatographic fractions (FDII, Lonomin V and Lonomin V-2) on extracellular matrix proteins was studied. The chromatographic fractions show activities similar to plasmin and urokinase. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, both lonomins appear as a protein band of 25 kDa under reduced conditions. By exclusion chromatography, the molecular weights of Lonomin V and Lonomin V-2 were 26.5 and 24.5 kDa, respectively. Fibronectin, laminin and vitronectin were degraded by all venom components. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, under reduced conditions, shows that lonomins degrade fibronectin in four main fragments of 116, 60, 50 and 30 kDa. Molecular exclusion chromatography in native conditions shows that the molecular masses of these fragments are > or = 300, 62 and 27 kDa. The proteolytic effect of lonomins was abolished by benzamidine/HCl, iodoacetic acid and aprotinin. The extracellular matrix protein degradation together with the fibrino(geno)lytic activity of hemolymph and its fractions could explain, in part, the hemorrhagic syndrome, and the wound dehiscence in persons who have had contact with the L. achelous caterpillar. 相似文献
82.
Sara Jo Nixon Austin L. Errico Oscar A. Parsons William R. Leber Cynthia J. Kelley 《Alcoholism, clinical and experimental research》1992,16(5):949-954
This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states. 相似文献
83.
Sara Mondini Francesca Borgo Biagio Cotticelli Patrizia Bisiacchi 《Journal of the International Neuropsychological Society》2006,12(2):275-284
The evolution of the progressive loss of semantic knowledge of a patient, VZ, with lesions mainly affecting the infero-medial temporal lobes, was followed for two years. At the beginning of the study VZ's performance was mainly characterized by a category-specific deficit for living things and a modality-specific deficit for perceptual attribute knowledge. As time went on, VZ's disorder affected all categories by changing the relationship between category and attribute knowledge. Data show that dissociations may change in the course of progressive cognitive breakdown, depending on both degeneration stage and task demands. VZ's performance is discussed in the light of the most influential theoretical accounts. Methodological suggestions regarding longitudinal studies of degenerative patients are also put forward. 相似文献
84.
85.
To date microscopy and cultural isolation still remain the “gold standard” in the laboratory diagnostics of mycobacteria. Nucleic acid amplification techniques additionally enable a rapid and sensitive detection of Mycobacterium tuberculosis. However, bacterial growth is still required for species identification and susceptibility testing which should be performed from one of the first isolates of every patient and repeated after about 2 months if cultures are still positive. By means of DNA fingerprint techniques, the confirmation of transmission, of TB outbreaks, and also of laboratory cross-contamination is feasible. 相似文献
86.
Kirsten M Robertson Maria Norg?rd Sara H Windahl Kjell Hultenby Claes Ohlsson G?ran Andersson Jan-Ake Gustafsson 《Journal of bone and mineral research》2006,21(8):1276-1287
The liver X receptor (alpha,beta) is responsible for regulating cholesterol homeostasis in cells. However, our studies using the LXRalpha-/-, LXRbeta-/-, and LXRalpha-/-beta-/- mice show that both LXRalpha and beta are also important for bone turnover, mainly by regulating osteoclast differentiation/activity. Introduction: The liver X receptors (alpha,beta) are primarily responsible for regulating cholesterol homeostasis within cells and the whole body. However, as recent studies show that the role for this receptor is expanding, we studied whether the LXRs could be implicated in bone homeostasis and development. MATERIALS AND METHODS: pQCT was performed on both male and female LXRalpha-/-, LXRbeta-/-, LXRalpha-/-beta-/-, and WT mice at 4 months and 1 year of age. Four-month-old female mice were additionally analyzed with reference to qPCR, immunohistochemistry, histomorphometry, transmission electron microscopy, and serum bone turnover markers. RESULTS: At the mRNA level, LXRbeta was more highly expressed than LXRalpha in both whole long bones and differentiating osteoblast-like MC3T3-E1 and osteoclast-like RAW 264.7 cells. Four-month-old female LXRalpha-/- mice had a significant increase in BMD because of an increase in all cortical parameters. No difference was seen regarding trabecular BMD. Quantitative histomorphometry showed that these mice had significantly more endosteal osteoclasts in the cortical bone; however, these cells appeared less active than normal cells as suggested by a significant reduction in serum levels of cross-linked carboxyterminal telopeptides of type I collagen (CTX) and a reduction in bone TRACP activity. Conversely, the female LXRbeta-/- mice exhibited no change in BMD, presumably because a significant decline in the number of the trabecular osteoclasts was compensated for by an increase in the expression of the osteoclast markers cathepsin K and TRACP. These mice also had a significant decrease in serum CTX, suggesting decreased bone resorption; however, in addition presented with an increase in the expression of osteoblast associated genes, bone formation markers, and serum leptin levels. CONCLUSIONS: Our findings show that both LXRs influence cellular function within the bone, with LXRalpha having an impact on osteoclast activity, primarily in cortical bone, whereas LXRbeta modulates trabecular bone turnover. 相似文献
87.
G Barzen C Schubert W Richter D Calder M B?rwald H Eichst?dt R Felix 《Strahlentherapie und Onkologie》1992,168(12):732-737
We evaluated the role of thallium-201 single-photon emission-computed tomography (SPECT) in diagnosis, differential diagnosis and follow-up of 33 patients with primary brain tumors. 27 of 33 lesions were detectable by Tl-201 SPECT because only two of eight low-grade (grade 1 and 2) astrocytomas showed Tl-201 accumulation up to a tumor to nontumor ratio of 2.6. High grade (grade 3 and 4) astrocytomas showed Tl-201 accumulation in the range of 2.2 up to 13.0 and were different from low-grade astrocytomas. Noninvasive grading of astrocytomas is therefore possible, whereas differential diagnosis of oligodendrogliomas and astrocytomas or meningiomas was not possible with Tl-201. In the follow-up of six patients, we could demonstrate, that tumor progression is correlated with increasing and tumor regression with decreasing Tl-201 accumulations. This functional changing proceed morphological findings in CT. But vanishing of Tl-201 accumulation during therapy does not mean vanishing of tumor as could be demonstrated by follow-up. 相似文献
88.
Gender differences in informal caring 总被引:1,自引:0,他引:1
Men have hitherto largely been invisible in research on informal care. This paper examines gender differences in informal caring, focusing on gender differences according to the relationship between the carer and care-recipient and the location of caring. The paper uses secondary analysis of the 1990–91 General Household Survey, which identified over 2700 adults as informal carers. Four per cent of men and women provide care for someone living in the same household. More women than men, 13% compared with 10%, provide care for someone living in another household. Men carers are less involved in care provision than women, providing fewer hours of care each week, and are less likely to be the main carer. However, gender differences are most marked among married carers, apart from those caring for their spouse, and least among unmarried carers. Married men can often rely on their wives to perform caring roles rather than performing them personally. Women carers are more likely to provide personal care than men carers, but the gender difference is least among those caring for their spouse or for disabled children. Cross-sex personal care is performed within the marital relationship and by parents caring for disabled children, but seldom by adult children caring for their parents or in more distant caring relationships. Evidence of cross-sex taboos in giving personal care is largely restricted to care provided in another household. Since the majority of elderly people in need of care are women, such cultural taboos may reinforce the pressure on mid-life women to care for mothers and mothers-in-law. 相似文献
89.
The following article presents two new cases of a lipofibroma of the median nerve. This formation is a very rare benign tumor of peripheral nerve tissue. Up to now 30 cases have been reported in the literature and are reviewed in this article and are compared with the two cases reported. Besides the operative treatment, which made the neuropathological diagnosis possible, preoperative diagnosis has been extended by MNT-scans of the involved parts of the nerve. The noninfiltrating character of the tumor could be well recognized on these scans. The signal quality and the anatomical proximity to the median nerve made the diagnosis of a lipofibroma likely. By the postoperative histological reviews the diagnosis was confirmed in classic manner. The immunological marking of the S-100 protein showed a remarkable reduction of this protein in these peripheral nerve tumors. The two cases reported by us recapitulate the clinical history typically and describe symptoms and our treatment for the lipofibroma of the median nerve. 相似文献
90.
The Changing Faces of the Nutcracker Esophagus 总被引:3,自引:0,他引:3
Christine B. Dalton P.A.C. Donald O. Castell M.D. Joel E. Richter M.D. 《The American journal of gastroenterology》1988,83(6):623-628
Although the nutcracker esophagus, characterized by high amplitude peristaltic contractions with mean distal amplitude greater than 180 mm Hg, is the most common esophageal motility disorder associated with noncardiac chest pain, little is known about its natural history. Therefore, we reviewed the manometric tracings of 23 patients with the nutcracker esophagus who had an average of 4.6 studies during a mean period of 32 months. Ten age-matched volunteers with normal baseline manometry who had undergone multiple studies (mean 5.8) over a mean time span of 32 months served as controls. In the 17 nutcracker patients with three or more motility studies, the variability of mean distal amplitudes between studies was 41.9% +/- 4.1 (+/- SE) compared to 27.0% +/- 3.3 for the control subjects (p less than 0.01). Highest distal pressures were noted during the first study in 11 of 17 patients (65%) compared to two of 10 controls (20%). The consistency of the diagnosis of nutcracker esophagus varied considerably: four patients always had high amplitude pressures, three patients only had the nutcracker diagnosis on the initial study, and 10 patients intermittently had pressures in the nutcracker range. Overall, these 17 patients had the diagnosis of the nutcracker esophagus confirmed on only 54% of subsequent studies. Changes in motility patterns were intermittently seen in six of 23 patients: one diffuse spasm and five nonspecific motility disorders. None of the control subjects developed high amplitude contractions or changed their motility pattern on serial testing. The possible pathophysiological implications of the changing faces of the nutcracker esophagus are discussed. 相似文献