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991.
The effect of 3-nitropropionic acid (3-NP), a selective inhibitor of succinic dehydrogenase, preconditioning on postischemic neurological deterioration and infarction was examined in gerbils after transient ischemia. The animals were pretreated with 1-80mg/kg of 3-NP 1 day before ischemia induced by two 10-min occlusions of the left common carotid artery. Four milligrams per kilogram 3-NP pretreatment significantly ameliorated postischemic neurological deterioration (stroke index at 7 days postischemia, 1.4+/-1.5 vs. 7.4+/-5.4 in 4 mg/kg-pretreated vs. non-pretreated animals: mean+/-SD) and reduced infarct volume (24+/-4.8 vs. 43+/-12 mm(3)). One and 20 mg/kg 3-NP induced milder neuroprotection, and 80 mg/kg 3-NP aggravated postischemic stroke symptoms and infarction. Thus, appropriate doze of 3-NP preconditioning is effective in ameliorating the postischemic neurological deterioration and reducing infarct volume.  相似文献   
992.
BACKGROUND: The consultation-liaison (C-L) psychiatrist is in an opportune position to undertake the tasks of education, training and assessment of performance as regards future physicians, psychiatrists, specialists in other branches and nurses. This paper describes the education and training programme in the Psychiatric-Psychosomatic C-L Service of Modena University Hospital. DESCRIPTION OF THE PROGRAMME: This programme consists of the following main activities: (1) daily group-case supervision, performed by the full-time psychiatrist together with the psychiatry residents of the C-L staff; (2) a bimonthly quality management meeting, which is part of a European project of measurement and improvement of quality of service; (3) weekly lectures on selected topics; (4) monthly tutorials in research techniques; (5) bimonthly presentations of literature reviews; (6) weekly clinical case conferences, which are the nucleus of the curriculum and which focus on the following main topics: 'the patients', 'the intervention' and 'the group', and (7) liaison meetings requested by non-psychiatric departments. CONCLUSIONS: A common denominator seen throughout the teaching and training activities of such a programme is the attitude of openness and effort toward integration which should be the C-L psychiatrist's distinguishing mark, in the context of the general hospital.  相似文献   
993.
A case of primary large cell splenic lymphoma of B lineage exhibiting filiform cell appearance is reported. The patient presented with massive splenomegaly, and following spontaneous splenic rupture, died of adult respiratory distress syndrome. The clinical aspects of the case, notably a lymphoma arising as a primary tumour in the spleen, with spontaneous spleen rupture and rapid fatal outcome, in combination with the filiform appearance of the lymphoma on electron microscopic examination, constitute an unusual combination of features. As far as is known, this B cell neoplasm is only the second primary splenic lymphoma of filiform type to be recorded.  相似文献   
994.
Bladder motility recordings were performed in anaesthetized rats and the effect of the peripherally active opiate agonist loperamide on urinary bladder function was studied. Regional intra-arterial administration of loperamide (0.01-2 mg kg-1) induced weak bladder contraction per se. Loperamide caused an effective dose-dependent inhibition of bladder motility induced by regional injection of the receptor agonists acetylcholine (ACh) and substance P (SP), as well as by peripheral motor nerve stimulation (PNS). Pretreatment with naloxone (0.5 mg kg-1) partially antagonized the inhibitory action of loperamide on the nerve-mediated detrusor contraction. However, the depression of the motor responses induced by the receptor agonists ACh and SP was not influenced. It is suggested that the demonstrated inhibitory effect of loperamide on bladder motility is partially mediated by peripheral opioid receptors. The main non-opioid part of the inhibition might be a direct smooth muscle action.  相似文献   
995.
996.
Pattern evoked responses were recorded in 46 patients of tuberculosis on ethambutol and 16 healthy subjects. Deterioration in visual acuity was documented in two patients (4.3%). P100 latency was delayed in 16 cases (34.8%), while in 12 patients (26.1%) both latency and amplitude were affected. A cut off latency value of > or = 140 ms was associated with ophthalmological findings. The incidence of subclinical toxicity as detected by visual evoked response (VER) was higher in older subjects, patients on higher doses of ethambutol (> or = 20 mg/kg/day) and longer duration of treatment. Of two cases with objective ocular signs, one who reported for follow up after two months had recovered completely after stopping ethambutol. Recording of VER is an extremely useful objective test for subclinical optic nerve damage.  相似文献   
997.
Abstract: A variety of reasons related to the HLA class I system has complicated the application of molecular approaches to HLA class I typing. Here we present a PCR-based HLA-A typing strategy considering the sequence variations of the two most polymorphic exons which allows complete subtyping of the HLA-A locus. The method is based on a sequence-specific amplification identifying the serologically defined HLA-A specificities. The PCR products generated by these group-specific primers bear the sequence information necessary for a postamplification specificity step. The primer pairs are located within one exon, either exon 2 or exon 3, which avoids amplification of polymorphic intron sequences allowing subsequent single-strand conformation polymorphism analysis and facilitating direct sequencing. Using this method we investigated 48 cell lines and 153 clinical samples. 23 PCR reactions are performed per individual for the assignment of the serological specificities A1-A80. The reproducibility was 100% in all cell lines and 85 clinical samples typed on two separate occasions. With the exception of 13 out of 231 possible serological combinations all homozygous and heterozygous combinations of A1-A80 can be distinguished by specific amplification patterns. Comparing the PCR based typing results with those of serology in 12% a discrepancy was found. Solid-phase sequencing or SSCP analysis of the group-specific PCR fragments allowed complete subtyping of the HLA-A locus. This strategy can identify all 48 HLA-A alleles based on the sequence variations of the 2nd and 3rd exon. 1128 homozygous and heterozygous allele combinations are possible for the HLA-A locus. Only 4 out of these 1128 allele combinations remained unresolved.  相似文献   
998.
In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules. Received: 20 August 1999 / Accepted: 2 November 1999  相似文献   
999.
Cancer of the larynx is fourteenth most common cancer in the world. Evidence from case-control studies conducted in developed as well as developing countries suggest that specific micro-nutrients and trace elements have been implicated to be significantly associated with laryngeal carcinoma. The association of these micro-nutrients and trace elements with laryngeal cancer has been discussed in this review article.  相似文献   
1000.
Long-term treatment with recombinant interleukin-2 (IL-2) of diabetes-prone BB rats had contrasting effects in two different BB rat sublines. Diabetes development was enhanced in the subline with a low intrinsic diabetes risk and suppressed in the subline with a high diabetes risk. IL-2 treatment started between 35 and 42 days of age and lasted for 3 months. In subline 1, diabetes incidence increased from 23% to 53% (P less than 0.01), in subline 2 it decreased from 73% to 32% (P less than 0.01). The two sublines differed in serum levels of factors controlling IL-2 synthesis and activity. Mean IL-2 inhibitory activity was higher in subline 2 (between 140% and 290% of levels in subline 1, P less than 0.01). Conversely, mean concentrations of thymosin alpha 1 and beta 4 were higher in subline 1 (between 140% and 200% of levels in subline 2, P less than 0.01). Thus the two sublines differ in their response to exogenous IL-2 and also in serum levels of mediators affecting availability of IL-2. We conclude that an internal network of hormonal factors, including IL-2, contributes to the control of diabetes development in the BB rat.  相似文献   
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