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31.
32.
Efficacies of the 5-hydroxytryptamine (serotonin) 5-HT3 receptor (5-HT3R) agonists 2-methyl-5-HT, dopamine, and m-chlorophenylbiguanide on 5-HT3R native to N1E-115 cells and on homopentameric 5-HT3R expressed in Xenopus oocytes were determined relative to that of 5-HT. Efficacies of 2-methyl-5-HT and dopamine on 5-HT3R native to differentiated N1E-115 cells are high (54 and 36%) as compared with their efficacies on homopentameric 5-HT3R-A(L) and 5-HT3R-A(S) receptors expressed in oocytes (4-8%). m-Chlorophenylbiguanide does not distinguish between 5-HT3R in N1E-115 cells and in oocytes. The distinct pharmacological profile of 5-HT3R native to differentiated N1E-115 cells is conserved when poly(A)+ mRNA from these cells is expressed in oocytes. The results indicate that, apart from the known 5-HT3R subunits, N1E-115 cells express additional proteins involved in 5-HT3R function.  相似文献   
33.
Exposure of T cells to their specific antigen normally results in proliferation, but in the presence of high and repeatedly administered doses of antigen, T cells may undergo apoptosis. Here we demonstrate that i.v. administration of as little as 100 microg of recombinant P2 protein twice daily completely prevents experimental autoimmune neuritis induced by adoptive transfer of neuritogenic P2-specific T cells or by immunization with the neuritogenic P2-peptide-spanning amino acids 53-78. Antigen treatment started after disease onset markedly ameliorated experimental autoimmune neuritis. The mechanism of action may be through programmed T cell death; a profound increase of the rate of apoptosis was seen in inflammatory foci of peripheral nerves and in the spleen. There was no cytokine switch by our Th1 cells after exposure to their specific antigen, but increased secretion of interferon gamma and tumor necrosis factor alpha was demonstrated. High antigen dose therapy using recombinant, pathogen-free protein may prove useful for the treatment of autoimmune inflammatory disorders of the nervous system.  相似文献   
34.
Comparatively few studies have examined the effects of methadone given during a clinical detoxification programme. Furthermore, their results are different especially because of changing drop-out rates. This study was carried out on a drug-detoxification ward and investigated the effects of methadone given to alleviate withdrawal symptoms. Comparisons were undertaken with patients withdrawn during a one-year period before methadone was available. No significant difference was found between drop-out rates of patients with methadone-supported detoxification (n = 113, drop-out rate: 41.6%) and patients who did not receive methadone during detoxification (n = 108, drop-out rate: 37.0%). Nevertheless the drop-out rate in the first three days of withdrawal was reduced from 15.7% to 8.0%. On average the critical drop-out moment shifted from 5.3 days to 10.1 days. Interpretations of these findings should take into account, that the number of patients who underwent a voluntary detoxification programme for the first time was nearly doubled after methadone was offered on the ward and, additionally, many more patients tried to withdraw from methadone taken within an outpatient methadone-maintenance programme.  相似文献   
35.
The topoisomerase II alpha (topo II alpha) enzyme is the target for several chemotherapeutic agents, including etoposide, teniposide, mitoxantrone, and doxorubicin (topo II poisons). The enzyme also is a marker of cell proliferation. Most cases of Hodgkin's disease (HD) are responsive to combination chemotherapy regimes that include topo II poisons such as doxorubicin. Immunoperoxidase methods for detection of the topo II alpha isoenzyme are now available for use in formalin-fixed, paraffin-embedded tissues, which may provide information about the proliferative capacity and possible sensitivity of tumors to drugs that target topo II. We used a specific antibody to analyze subsets of HD for topo II alpha staining patterns. Formalin-fixed blocks from 49 cases of HD, including 20 nodular sclerosis (NS), 14 mixed-cellularity (MC), and 15 lymphocyte-predominant (LP) subtypes, were analyzed by dual staining for topo II in combination with monoclonal antibodies against Reed-Sternberg (RS) cells consisting of CD15 for the NS and MC subtypes and CD20 for LP lymphocytic and histiocytic (L & H) cells. The number of morphologically appropriate cells coexpressing the RS or L & H marker and topo II alpha was quantitated. Positive nuclear staining for topo II alpha in RS or L & H cells was seen in 100% of cases, irrespective of subtype. Coexpression of CD15 and topo II alpha was seen in 58.4% of the RS cells or mononuclear variants in NSHD cases and 68.4% in MCHD cases. No significant difference in the percentage of neoplastic cells expressing topo II alpha was found between NS and MC subtypes. Cases of LPHD showed coexpression of CD20 and topo II alpha in 84.4% of the L & H cells, a significant increase over the level of tumor cell coexpression seen in NSHD and MCHD (P < .001). Only one case was found to have a low (< 25% of tumor cell coexpression) level of topo II alpha expression. Immunohistochemical detection of a high level of topo II alpha expression in HD, irrespective of subtype, suggests a molecular explanation for the excellent response of most HD to standard combination chemotherapy, which can include topo II poisons. The LP subtype has a higher expression of topo II alpha in the neoplastic cell population than do NS or MC subtypes, perhaps indicating increased sensitivity of these tumors to topo II poisons. It may be possible to identify subsets of HD that are more or less sensitive to conventional chemotherapeutic regimes, which would help in the selection of appropriate treatment.  相似文献   
36.
PURPOSE: Patients with primary cutaneous melanoma with a Breslow thickness > or = 1.5 mm have only a 30% to 70% probability of survival after surgery, and no adjuvant therapy has so far improved this outcome. Since interferon alfa-2a (IFNalpha2a) exhibits antitumor activity in metastatic melanoma, we investigated whether adjuvant IFNalpha2a diminishes the occurrence of metastases and thus prolongs disease-free survival in melanoma patients after excision of the primary tumor. PATIENTS AND METHODS: In a prospective randomized study, 311 melanoma patients with a Breslow thickness > or = 1.5 mm were assigned to either adjuvant IFNalpha2a treatment (n = 154) or observation (n = 157) after excision of the primary tumor. IFNalpha2a was given daily at a dose of 3 mIU subcutaneously (s.c.) for 3 weeks (induction phase), after which a dose of 3 mIU s.c. three times per week was given over 1 year (maintenance phase). RESULTS: Prolonged disease-free survival was observed in patients treated with IFNalpha2a versus those who underwent surgery alone. This difference was significant (P = .02) for all patients enrolled onto the study (intention-to-treat analysis) at a mean observation time of 41 months. Subgroup analysis showed that Breslow tumor thickness had no influence on treatment results in the groups of patients investigated. CONCLUSION: Adjuvant IFNalpha2a treatment diminishes the occurrence of metastases and thus prolongs disease-free survival in resected primary stage II cutaneous melanoma patients.  相似文献   
37.
OBJECTIVE: To report our experience with erosion of permanent suture or mesh material after abdominal sacrocolpopexy. METHODS: A retrospective chart review was performed to identify patients who underwent sacrocolpopexy by the same surgeon over 8 years. Demographic data, operative notes, hospital records, and office charts were reviewed after sacrocolpopexy. Patients with erosion of either suture or mesh were treated initially with conservative therapy followed by surgical intervention as required. RESULTS: Fifty-seven patients underwent sacrocolpopexy using synthetic mesh during the study period. The mean (range) postoperative follow-up was 19.9 (1.3-50) months. Seven patients (12%) had erosions after abdominal sacrocolpopexy with two suture erosions and five mesh erosions. Patients with suture erosion were asymptomatic compared with patients with mesh erosion, who presented with vaginal bleeding or discharge. The mean (+/-standard deviation) time to erosion was 14.0+/-7.7 (range 4-24) months. Both patients with suture erosion were treated conservatively with estrogen cream. All five patients with mesh erosion required transvaginal removal of the mesh. CONCLUSION: Mesh erosion can follow abdominal sacrocolpopexy over a long time, and usually presents as vaginal bleeding or discharge. Although patients with suture erosion can be managed successfully with conservative treatment, patients with mesh erosion require surgical intervention. Transvaginal removal of the mesh with vaginal advancement appears to be an effective treatment in patients failing conservative management.  相似文献   
38.
This paper uses definitions of a consensus conference (ACCP/CCM) describing the epidemiology of SIRS, sepsis and septic shock in surgical ICU patients. During a period of 2 years a total of 656 patients were prospectively enrolled into the study. 335 patients (51.1% of the total population) developed SIRS (systemic inflammatory response syndrome); in 65 of these patients infection could be documented, i.e. they met the criteria of sepsis, 47 of these 65 septic patients developed septic shock, with mortality of 53.2%. SIRS is associated with a high sensitivity but a low specificity in predicting the outcome of ICU patients. Moreover, SIRS and sepsis appear to be of minor clinical relevance. On the contrary, septic shock describes a very high risk group of patients which should be characterized more closely in future studies.  相似文献   
39.
BACKGROUND: The glial protein S100beta has been used to estimate cerebral damage in a number of clinical settings. The purpose of this investigation was to determine the correlation between cerebral microemboli and S100beta levels during cardiac operations. METHODS: Transcranial Doppler ultrasonography was used to measure emboli in the right middle cerebral artery. Emboli counts (n = 111) were divided into five time periods: (1) incision to aortic cannulation; (2) aortic cannulation to cross-clamp onset; (3) cross-clamp onset to cross-clamp release; (4) cross-clamp release to decannulation; and (5) decannulation to chest closure. The level of S100beta (n = 156) was measured at baseline, at the end of cardiopulmonary bypass, then 150 and 270 minutes after cross-clamp release. RESULTS: The level of S100beta correlated with age, cardiopulmonary bypass time, cross-clamp time, and number of emboli at time period 2. Although cardiopulmonary bypass time was univariately associated with S100beta level, it became nonsignificant in a multivariable model that included age and cross-clamp time. CONCLUSIONS: The correlation of S100beta level with emboli measured during cannulation (time period 2) supports the hypothesis that cannulation is a high-risk time period for cerebral injury.  相似文献   
40.
214 ewes suffering from pregnancy toxaemia (ketosis) were examined. Clinical signs during onset and course of disease and laboratory findings were compared between animals that survived and those which died. In the latter the onset of ketosis was earlier in pregnancy (day 143 +/- 7 vs. day 146 +/- 8) and duration of the disease was shorter (10 +/- 13 vs. 14 +/- 9 days). The animals that died showed more severe clinical signs and higher values of 3-hydroxy-butyrate (4.3 +/- 3.6 vs. 3.5 +/- 2.6 mmol/l) and cortisol (72 +/- 98 vs. 52 +/- 80 mmol/l) as well as lower values of insulin (37 + 12 vs. 3.5 + 2.6 mmol/l) and potassium (4.1 + 1.0 vs. 4.4 + 1.0 mmol/1) at onset of the disease than those which survived (all of differences with P < 0.05). Glucose levels did not differ between groups. Treated animals with glucose plus fructose infusions (n = 56) or with oral application of glucose precursors plus electrolytes (n = 126) had survival rates of 53.6% and 62.7%, respectively. Oral treatment with glucose precursors plus electrolytes and an additional subcutaneous insulin treatment (n = 15) led to an enhanced survival rate of 86.7% (P < 0.05). Low insulin levels in ketotic pregnant sheep and the therapeutic effect of insulin treatment support the hypothesis that insulin plays a causative role in the pathogenesis of ovine ketosis.  相似文献   
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