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991.
The inhibitory effect of inflammation and endotoxins on the secretion of reproductive hormones from the hypothalamo-pituitary axis is well documented. A comparison of the luteinizing hormone (LH) suppressing effects of several pro-inflammatory cytokines revealed that centrally administered IL-1 beta was the most potent inhibitor of pituitary LH secretion; interleukin (IL)-1 alpha and tumor necrosis factor (TNF) alpha were relatively less effective, whereas IL-6 was ineffective. This order of potency suggested that the anti-gonadotropic effects of an immune challenge are most likely attributable to the action of centrally released IL-1 beta, and this was supported by the demonstration that IL-1 beta suppressed hypothalamic luteinizing hormone releasing hormone (LHRH) release. We used a multifaceted approach to identify the afferent signals in the brain that convey immune messages to hypothalamic LHRH neurons. Pharmacological studies with specific antagonists of opioid receptor subtypes demonstrated that activation of the mu 1 receptor subtype was required to transmit the cytokine signal. Furthermore, icv IL-1 beta upregulated hypothalamic POMC mRNA and increased the concentration and release of beta-endorphin, the primary ligand of mu 1 receptors. We have obtained evidence that IL-1 beta also enhanced the gene expression and concentration of tachykinins, a family of nociceptive neuropeptides in the hypothalamus. Blockade of tachykinergic NK2 receptors attenuated IL-1 beta induced inhibition of LH secretion. Collectively, these results demonstrate that IL-1 beta, generated centrally in response to inflammation, upregulates the opioid and tachykinin peptides in the hypothalamus. These two groups of neuropeptides are critically involved in relaying the cytokine signal to neuroendocrine neurons and causing the suppression of hypothalamic LHRH and pituitary LH release.  相似文献   
992.
Comparative analysis was performed of results of the treatment of patients with ischemic stroke, including 140 ones treated by means of hemodilution method (control group) and 40 patients treated with cerebrolysin (test group). Barolin's scale of the neurorehabilitation was used for the analysis of the results. Statistically significant results of rehabilitation were better in the test group. Improvement of the parameters characterizing social contacts, working activity and behaviour was more pronounced than an improvement of motor functions. Cerebrolysin had accelerating effect on restoration of damaged functions, by creating more stable basis for rehabilitation.  相似文献   
993.
Stimulus equivalence is a behavioral approach to analyzing the "meaning" of stimulus sets and has an implication for clinical psychology. The formation of three-member (A --> B --> C) stimulus equivalence classes was used to investigate the effects of three different sets of sample and comparison stimuli on emergent behavior. The three stimulus sets were composed of Rational-Emotive Behavior Therapy (REBT)-related words, non-REBT emotionally charged words, and a third category of neutral words composed of flower labels. Sixty-two women and men participated in a modified matching-to-sample experiment. Using a mixed cross-over design, and controlling for serial order effects, participants received conditional training and emergent relationship training in the three stimulus set conditions. Results revealed a significant interaction between the formation of stimulus equivalence classes and stimulus meaning, indicating consistently biased responding in favor of reaching criterion responding more slowly for REBT-related and non-REBT emotionally charged words. Results were examined in the context of an analysis of the importance of stimulus meaning on behavior and the relation of stimulus meaning to behavioral and cognitive theories, with special appraisal given to the influence of fear-related discriminative stimuli on behavior.  相似文献   
994.
995.
OBJECTIVE: To determine prevalence and severity of carboplatin-induced dose-limiting toxicoses in the cat. ANIMALS: 9 healthy, 6- to 7-month-old cats weighing 4.7 (range, 3.0 to 6.5) kg. PROCEDURE: Cats were given a single i.v. bolus of carboplatin at a dosage of 150 (n = 3), 200 (n = 3), or 250 (n = 3) mg/m2 of body surface area. RESULTS: Dose-limiting neutropenia and thrombocytopenia were significant in all cats given carboplatin at 200 or 250 mg/m2. Weight loss, changes in appetite, and evidence of respiratory difficulty, as well as vomiting, diarrhea, or lethargy were not observed at any time during the 28-day period. At a highest dosage (250 mg/m2), the neutrophil nadir (560 +/- 303 neutrophils/microliters) was observed on day 17 and the platelet count nadir (96,500 +/- 11,815 platelets/microliters) was observed on day 14 after carboplatin administration. CONCLUSIONS: Carboplatin appears to be safe and clinically well-tolerated when given i.v. as a single bolus at a dosage of 200 mg/m2 to clinically normal cats. The dose-limiting toxicity of a single i.v. administered bolus is neutropenia. The nadir of a 200 mg/m2 i.v. administered dose occurs on day 17 (1,110 +/- 165 neutrophils/microliters) and neutropenia (< 2,000 neutrophils/microliters) lasts from day 14 through day 25 after carboplatin administration. CLINICAL RELEVANCE: The fatal dose-related pulmonary toxicosis observed in cisplatin-treated cats was inapparent in carboplatin-treated cats. To adequately determine the therapeutic role of carboplatin in tumor-bearing cats, a moderately tolerated dose of carboplatin of 200 mg/m2 given i.v. once every 4 weeks should be considered.  相似文献   
996.
Neurologists are being asked to incorporate methods into daily practice that measure quality of care. Standards of care are increasingly being defined using evidence-based assessments of neurological literature. To evaluate quality of care, a widely accepted and useful model considers the structure, process, and outcomes of care. Outcomes, the impact of care on patients' health, should include measures of mortality, morbidity, disability, patient functioning and well-being (health-related quality of life), and patient satisfaction with care. A variety of private organizations and government programs exist to encourage documentation and promotion of high quality of care. This explosion in quality information is not yet standardized, so that much confusion exists about appropriate data elements to be measured. The challenge is to collect, summarize, and disseminate practical data useful to neurologists and the purchasers and consumers of our services.  相似文献   
997.
Myeloablative therapy followed by allogeneic bone marrow transplantation (BMT) has proven to be curative therapy in patients with hematologic malignancies. Relapse, however, remains a major cause of treatment failure for patients with advanced disease. During the past 15 years, we have gained considerable experience with the combination of fractionated total-body irradiation (FTBI) and etoposide followed by allogeneic BMT for hematologic malignancies. In an attempt to decrease post-transplant relapse rates, 67 patients under the age of 50 years with high-risk or advanced-stage hematological malignancies received an intensified regimen of FTBI and etoposide plus cyclophosphamide followed by BMT from a genotypically-matched related donor. The regimen consisted of 1320 cGy of FTBI in 11 fractions, 60 mg/kg of etoposide (VP-16), and 60 mg/kg of cyclophosphamide (CY). Fifty-three patients received cyclosporine and prednisone for graft-vs.-host disease (GVHD) prophylaxis and 14 patients received cyclosporine, methotrexate, and prednisone. Diagnosis at BMT included 45 patients with acute leukemia, 7 patients with chronic leukemia, and 15 patients with high-grade non-Hodgkin's lymphoma (NHL). Actuarial disease-free survival (DFS) at 3 years was 42% +/- 12% for the entire group with a median follow-up of 50 months (range 20-74) for 28 patients who remain alive in continued complete remission (CR). Actuarial 3-year-DFS was 38% +/- 14% in 52 patients with acute or chronic leukemia and 60% +/- 25% in 15 patients with NHL with relapse rates of 45% +/- 16% and 21% +/- 11%, respectively. DFS at 3 years was 40% +/- 18% in 32 patients with acute leukemia in 1st relapse or 2nd CR or chronic myelogenous leukemia in accelerated phase, and was 32% +/- 22% in 20 patients with more advanced disease. Regimen related mortality occurred in 9 patients (4, veno-occlusive disease of the liver; 2, multi-organ failure; 1, diffuse alveolar hemorrhage; 1, central nervous system (CNS) hemorrhage; 1, adult respiratory distress syndrome (ARDS). The combination of FTBI, etoposide, and cyclophosphamide followed by allogeneic BMT is an effective and relatively well-tolerated regimen for patients with advanced hematologic malignancies. The role for this regimen should be further defined by prospective clinical trials.  相似文献   
998.
Acute lymphoblastic leukemia (ALL) occurring in infants less than 1 year of age differs clinically and biologically from that observed in older children. Cytogenetically, 11q23 translocations are detected in approximately 50% of infant ALLs and fuse the 11q23 gene HRX with a variety of partner chromosomal loci. Overall, HRX rearrangements are detected molecularly in 70-80% of infant ALLs as compared to 5-7% of ALLs arising in older children. Two recently described molecular abnormalities in childhood ALL are ETV6 gene rearrangements and homozygous deletions of p16(INK4A) and/or p15(INK4B). Each of these abnormalities occurs in 15-20% of all childhood ALLs, and neither can be accurately identified by routine cytogenetic analyses. The incidence of these genetic abnormalities and their potential relationship to HRX gene status in infant ALL is unknown. Using Southern blot analyses, we determined ETV6 and p16(INK4A)/p15(INK4B) gene status in a cohort of infant ALLs. No ETV6 rearrangements or homozygous deletions (n=69) or homozygous p16(INK4A) and/or p15(INK4B) gene deletions (n=54) were detected in any of the infant ALLs. Therefore, ETV6 and p16(INK4A)/p15(INK4B) do not play a significant role in the pathogenesis of infant ALL, further emphasizing the distinctive biology of this subset of leukemias.  相似文献   
999.
The immunoregulatory functions of IL-4 and IL-5 have identified these cytokines as primary targets for the resolution of airways inflammation and bronchial hyperreactivity in asthma. However, the individual contribution of each of these cytokines and of IL-5-regulated eosinophilia to the induction of airways hyperreactivity in mouse models of asthma remains highly controversial. In this investigation, we have used IL-4- and IL-5-deficient mice of the same genetic background in combination with inhibitory mAbs to these cytokines to identify unequivocally the contribution of these factors to the induction of airways hyperreactivity. Sensitization and aeroallergen challenge of wild-type mice with OVA induced pathological changes to the respiratory epithelium, airways eosinophilia, and hyperreactivity to beta-methacholine. Inhibition of the actions of IL-4 and/or IL-5 did not abolish airways hyperreactivity, and in the case of IL-4-deficient mice pretreated with anti-IL-5 mAb, airways hyperreactivity persisted in the absence of pronounced airways inflammation. Airways hyperreactivity was abolished only by anti-CD4+ mAb treatment. However, aeroallergen challenge of IL-5-/- mice showed that morphologic changes to the airways were critically linked to IL-5 and eosinophilia. This investigation demonstrates the existence in BALB/c mice of a novel CD4+ T cell pathway for modulating airways hyperreactivity. These findings may provide an explanation for the dissociation of airways eosinophilia from the development of airways hyperreactivity observed in some cases of asthma and in animal models of this disease.  相似文献   
1000.
TB Gilbert  SP Gaine  LJ Rubin  AJ Sequeira 《Canadian Metallurgical Quarterly》1998,22(10):1029-32; discussion 1033
Pulmonary complications including hypoxemia, right heart failure, and prolonged ventilation may follow pulmonary thromboendarterectomy (PTE) performed via cardiopulmonary bypass (CPB) with deep hypothermic circulatory arrest. Seventeen adult patients have undergone PTE at the University of Maryland Medical System during the preceding 3 years. From these patients, clinical and hemodynamic parameters were tabulated pre-CPB, post-CPB, at admission to the intensive care unit (ICU), and prior to discontinuation of invasive monitoring in the ICU. Data on anthropometric variables, survival, and times of extracorporeal circulation, mechanical ventilation, and hospital stay were also collected. The mean values for pulmonary arterial systolic and diastolic pressures and pulmonary vascular resistance (PVR) decreased significantly from pre-CPB values after PTE (all p < 0.05). Mild mixed acidosis present at ICU admission resolved prior to discharge (p = 0.002). The length of mechanical ventilation time was positively correlated with the absolute post-CPB PVR and negatively correlated with the relative change in central venous pressure (CVP) from pre-CPB to post-CPB values (r = 0.75, p = 0.037). Of the pre-CPB anthropometric variables, only body mass index was significantly higher in nonsurvivors (p = 0.037). Pulmonary artery pressures and vascular resistance fall significantly after PTE. A lower post-CPB PVR and a relatively decreased (i.e., from pre-CPB values) CVP predict reduced length of postoperative ventilation but not of the hospital stay. Mortality appears increased in patients with a large body habitus.  相似文献   
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