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31.
The GABA transaminase inhibitors gamma-acetylen GABA (GAG) and sodium valproate were administered intraperitoneally and their effects on locomotor activity, motor execution and sexual behavior were analyzed. It was found that sodium valproate, administered 15 min before observation, reduced locomotor activity only at a dose of 200 mg/kg. Doses of 100 and 400 mg/kg had no effect. Motor execution was impaired in a dose-dependent way, the lowest effective dose being 200 mg/kg. Sexual behavior was also dose-dependently reduced. Sodium valproate, administered 60 min before observation, inhibited all behaviors. The lowest effective dose was 200 mg/kg for locomotor activity and 400 mg/kg for motor execution and sexual behavior. GAG also inhibited all behavior, in doses ranging from 25 mg/kg (locomotor activity) to 100 mg/kg (motor execution and sexual behavior). The data showed that there is no relation between effects on locomotor activity and the effects on sexual behavior, whereas sexual behavior is inhibited whenever motor execution is impaired. Moreover, there is no correlation between effects on locomotor activity and motor execution. It is suggested that GABA transaminase inhibitors effect sexual behavior only indirectly, via an impairment of motor execution. Therefore it is doubtful whether GABAergic mechanisms play any role in the normal regulation of sexual behavior.  相似文献   
32.
ObjectiveWe aimed to evaluate the accuracy of sentinel lymph node (SLN) mapping with transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) to detect lymph node (LN) metastases, in patients with intermediate and high-risk endometrial cancer (EC), focusing on its performance to detect paraaortic involvement.MethodsProspective study including women with preoperative intermediate or high-risk EC, according to ESMO-ESGO-ESTRO consensus, who underwent SLN mapping using the TUMIR approach. SLNs were preoperatively localized by planar and single photon emission computed tomography/computed tomography images, and intraoperatively by gamma-probe. Immediately after SLN excision, all women underwent systematic pelvic and paraaortic lymphadenectomy by laparoscopy.ResultsThe study included 102 patients. The intraoperative SLN detection rate was 79.4% (81/102). Pelvic and paraaortic drainage was observed in 92.6% (75/81) and 45.7% (37/81) women, respectively, being exclusively paraaortic in 7.4% (6/81). After systematic lymphadenectomy, LN metastases were identified in 19.6% (20/102) patients, with 45.0% (9/20) showing paraaortic involvement, which was exclusive in 15.0% (3/20). The overall sensitivity and negative predictive value (NPV) of SLNs by the TUMIR approach to detect lymphatic involvement were 87.5% and 97.0%, respectively; and 83.3% and 96.9%, for paraaortic metastases. After applying the MSKCC SLN mapping algorithm, the sensitivity and NPV were 93.8% and 98.5%, respectively.ConclusionThe TUMIR method provides valuable information of endometrial drainage in patients at higher risk of paraaortic LN involvement. The TUMIR approach showed a detection rate of paraaortic SLNs greater than 45% and a high sensitivity and NPV for paraaortic metastases in women with intermediate and high-risk EC.  相似文献   
33.
Cytogenetic and histologic correlations in malignant lymphoma   总被引:9,自引:0,他引:9  
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change.  相似文献   
34.
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.  相似文献   
35.
Factors associated with poor outcomes in patients with lupus nephritis   总被引:1,自引:0,他引:1  
The objective of this study was to identify the factors associated with important clinical outcomes in a case-control study of 213 patients with lupus nephritis. Included were 47% Hispanics, 44% African Americans and 9% Caucasians with a mean age of 28 years. Fifty-four (25%) patients reached the primary composite outcome of doubling serum creatinine, end-stage renal disease or death during a mean follow-up of 37 months. Thirty-four percent African Americans, 20% Hispanics and 10% Caucasians reached the primary composite outcome (P < 0.05). Patients reaching the composite outcome had predominantly proliferative lupus nephritis (WHO classes: 30% III, 32% IV, 18% V and 5% II, P < 0.025) with higher activity index score (7 +/- 6 versus 5 +/- 5, P < 0.05), chronicity index (CI) score (4 +/- 3 versus 2 +/- 2 unit, P < 0.025), higher baseline mean arterial pressure (MAP) (111 +/- 21 versus 102 +/- 14 mmHg, P < 0.025) and serum creatinine (1.9 +/- 1.3 versus 1.3 +/- 1.0 mg/dL, P < 0.025), but lower baseline hematocrit (29 +/- 6 versus 31 + 5%, P < 0.025) and complement C3 (54 +/- 26 versus 65 + 33 mg/dL, P < 0.025) compared to controls. More patients reaching the composite outcome had nephrotic range proteinuria compared to controls (74% versus 56%, P < 0.025). By multivariate analysis, CI (hazard ratio [95% CI] 1.18 [1.07-1.30] per point), MAP (HR 1.02 [1.00-1.03] per mmHg), and baseline serum creatinine (HR 1.26 [1.04-1.54] per mg/dL) were independently associated with the composite outcome. We concluded that hypertension and elevated serum creatinine at the time of the kidney biopsy as well as a high CI are associated with an increased the risk for chronic renal failure or death in patients with lupus nephritis.  相似文献   
36.
Leprosy is a disease consisting of a spectrum of clinical, bacteriological, histopathological and immunological manifestations. Tuberculoid leprosy is frequently recognized as the benign polar form of the disease, while lepromatous leprosy is regarded as the malignant form. The different forms of leprosy depend on the genetic and immunological characteristics of the patient and on the characteristics of the leprosy bacillus. The malignant manifestations of lepromatous leprosy result from the mycobacterial‐specific anergy that develops in this form of the disease. Using murine leprosy as a model of anergy in this study, we first induced the development of anergy to Mycobacterium lepraemurium (MLM) in mice and then attempted to reverse it by the administration of dialysable leucocyte extracts (DLE) prepared from healthy (HLT), BCG‐inoculated and MLM‐inoculated mice. Mice inoculated with either MLM or BCG developed a robust cell‐mediated immune response (CMI) that was temporary in the MLM‐inoculated group and long‐lasting in the BCG‐inoculated group. DLE were prepared from the spleens of MLM‐ and BCG‐inoculated mice at the peak of CMI. Independent MLM intradermally‐inoculated groups were treated every other day with HLT‐DLE, BCG‐DLE or MLM‐DLE, and the effect was documented for 98 days. DLE administered at a dose of 1.0 U (1 × 106 splenocytes) did not affect the evolution of leprosy, while DLE given at a dose of 0.1 U showed beneficial effects regardless of the DLE source. The dose but not the specificity of DLE was the determining factor for reversing anergy.  相似文献   
37.
Rick  ME; Krizek  DM 《Blood》1986,67(6):1649-1654
Factor VIII coagulant protein (VIII:C) functions as a critical cofactor with factor IXa, calcium ions, and phospholipid during the activation of factor X. In the course of this reaction, the activity of VIII:C is first increased and then is destroyed by one or more serine proteases that are part of the coagulation sequence. In this study, we have investigated the influence of platelets on the inactivation of VIII:C by plasmin. Platelets were separated from plasma proteins in the presence of granule release inhibitors and were incubated with plasmin and isolated VIII:C or the complex of purified VIII:C/von Willebrand factor (vWF); VIII:C activity and antigen levels were assessed over time. In the presence of platelets, the isolated VIII:C showed an initial increase in VIII:C activity that was not present when platelets were absent, and the VIII:C/vWF showed an increase in VIII:C activity over that seen when platelets were absent. In addition, platelets stabilized VIII:C activity over a one-hour time course when compared with buffer. The VIII:C antigen did not increase and decreased slowly whether platelets were present or absent. Preincubating the platelets with ristocetin, collagen, or plasmin did not alter the results, and experiments using platelets from a patient with severe von Willebrand's disease also showed a pattern similar to that seen with normal platelets. Experiments using fixed platelets or phospholipid vesicles showed that they did not support the activation reaction or delay the inactivation reaction. These studies demonstrate that platelets modulate the activation and inactivation of VIII:C by plasmin, apparently by a mechanism that is independent of the platelet release reaction.  相似文献   
38.
AIM: To describe the prevalence of cocaine and other drug use in secondary school students in Oviedo (Asturias, Northern Spain) and determine the personality features and levels of sensation seeking in cocaine users. METHODS: 2,862 secondary school students (mean age +/- SD = 15.87+/-1.48 years; 50.6% males) were interviewed during the 1998-1999 academic year. For evaluation, the World Health Organization questionnaire for drug consumption, the Eysenck Personality Questionnaire (EPQ) for adults and the Zuckerman Sensation Seeking Scale were used. RESULTS: The prevalence of lifetime, previous year and previous month cocaine use among secondary school students was 6.1, 4.9 and 2.7%, respectively. Cocaine ranked sixth among illicit drugs ever used by this population. Once individuals had used cocaine for the first time, they were likely to use it again (44.8% of those who had ever used cocaine reported that they had done so in the previous month). Compared to students who had never used cocaine (but who may have used other substances), cocaine users had a more extensive drug abuse history. Students who had used cocaine at some point during their lifetime scored significantly higher on the EPQ psychoticism subscale and reported higher levels of sensation seeking. CONCLUSIONS: There is a significant rate of cocaine consumption amongst secondary school students of both sexes. Cocaine users are polyconsumers of other substances, both legal and illicit. Those who consume cocaine have a different psychological profile, characterized by high sensation seeking and high levels of psychoticism.  相似文献   
39.
Standardization of sequence chromatogram analysis is required for consistent genotypic tropism determination across laboratories. A freely available, fast, and automated chromatogram analysis tool (RECall) provided tropism interpretations equivalent to those of manual sequence editing of 521 V3 loop HIV-1 population sequences, suggesting that RECall can be useful in standardizing genotypic tropism testing across laboratories.  相似文献   
40.
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