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991.
Insufficient immunosurveillance is an important aspect in early tumorigenesis and in the pathogenesis of malignant disease. In the later course of cancer, the development of immunodeficiency is considered the major reason for disease progression and death. Within the anti-tumoral host defense reaction, Th1-type cytokine interferon-gamma (IFN-gamma) is of particular relevance. IFN-gamma stimulates several anti-proliferative and thus tumoricidal biochemical pathways in macrophages and other cells and also in tumor cell lines. These include inducible nitric oxide synthase, indoleamine (2, 3)-dioxygenase, an enzyme degrading the essential amino acid tryptophan, and the production of reactive oxygen species and neopterin in human macrophages and dendritic cells. Although the anti-proliferative strategy of the immune system aims to inhibit the growth of malignant cells, it can also affect T-cell response and thus contribute to the development of immunodeficiency. Accelerated degradation of tryptophan and increased production of neopterin were found to parallel the course of malignant diseases. Moreover, a higher degree of these metabolic changes characterizes poor prognosis and is associated with the development of anemia, weight loss and depressive mood in patients. Available data suggest that immunodeficiency in cancer patients may develop as a long-term side-effect of the antiproliferative and pro-apoptotic mechanisms elicited within Th1-type immune response, and enhanced production of pro-inflammatory cytokine IFN-gamma seems to be critically involved.  相似文献   
992.
The synthesis and the in vitro and in vivo antibacterial activities of a series of N-acylated phenylglycine cephalosporins are described. These compounds exhibit activity against a broad spectrum of gram-positive and gram-negative bacteria including some strains of Pseudomonas aeruginosa, a bacterial species normally insensitive to the cephalosporin antibiotics. The cephalosporins were prepared by acylation of cephaloglycin or its 3-tetrazolylthiomethyl analogue. In several cases, the acylations produced mixtures of diastereomeric cephalosporins, the components of which, when separated, showed different levels of antibiotic activity. Optimum activity was obtained when the acyl moiety on the phenylglycine nitrogen contained an oxygen atom centrally located between the amide carbonyl and a carboxyl substituent, preferably in a three- or five-membered ring. Replacement of acetoxymethyl by (1-methyl-1H-tetrazol-5-yl)thiomethyl at the 3 position resulted in overall improvement in activity both in vitro and in vivo. Against a group of P. aeruginosa strains, the best compounds of this series showed activity on the order of carbenicillin.  相似文献   
993.
994.
Bovine ovarian follicles were individually aspirated to obtain granulosa cells and follicular fluid, and estrogen concentrations in fluid were measured with a radioimmunoassay. Granulosa membranes were harvested by centrifugation and were pooled from follicles containing statistically high or low estrogen. Granulosa cell concentrations were estimated by comparing their protein content to cell standards. Results showed that cell numbers increased with increasing follicle size, and follicles with high estrogen concentrations possessed more granulosa than follicles with low estrogen. Specific binding of [3H]heparin decreased with advancing follicle size and was higher to granulosa harvested from follicles containing low estrogen.  相似文献   
995.
996.
Zusammenfassung Es wurde die Serumarginaseaktivität von Kontrollpersonen (gesunder Blutspender und an neurologischen Krankheiten leidender Patienten) und einer Anzahl an verschiedenen psychiatrischen Krankheiten leidenden Patienten bestimmt und festgestellt, daß diese bei Depressionen signifikant erhöht ist. Bei biphasischem Psychosenverlauf wurden phasenabhängige Veränderungen des Serumarginasespiegels beobachtet: Normale Werte in der Manie, höhere im Phasen-intervall, höchste Aktivität in der Depression.Frl. Pirosehka Engi und Frl. Maria Payer sei an dieser Stelle für die sorgfältige Assistenzarbeit gedankt.  相似文献   
997.
BACKGROUND: Hot-spot microvessel density (MVD) and vascular patterns have been reported as histopathologic factors that influence prognosis in retrospective series of malignant gliomas. To investigate clinical utility, the authors systematically studied observer agreement on MVD and vascular patterns and the influence of repeatedly assessed data on patient outcomes in 2 independent glioblastoma series. METHODS: MVD and vascular patterns were assessed retrospectively by 5 observers in 1) a retrospectively compiled glioblastoma series that included 110 patients and 2) a glioblastoma series that included 233 patients who were treated within a randomized trial. MVD was determined in the field of greatest density ("hot-spot"). Predominantly classic or bizarre vascular patterns were determined by using a previously defined algorithm. RESULTS: Observer agreement on MVD was highly variable (range of kappa values, 0.464-0.901). The worst observer agreement was achieved when both the selection of hot-spots and MVD counts were performed independently. Survival analysis did not show a consistent association between repeatedly assessed MVD and patient outcome. Observer agreement on vascular patterns was poor (kappa = 0.297). Survival analysis did not show a consistent association between repeatedly assessed vascular patterns and patient outcome. CONCLUSIONS: Observer agreement on hot-spot MVD and vascular patterns in patients with glioblastoma was poor in independent assessments. MVD and vascular patterns were not associated consistently with patient outcome. Based on these findings, the authors concluded that poor observer agreement limits the clinical utility of histopathologically assessed hot-spot MVD and vascular patterns as prognostic factors in patients with glioblastoma. Improved methodologies for morphologic assessment of glioblastoma vascularization need to be identified.  相似文献   
998.

Purpose

The objective of this phase II study was to determine the response rate in patients with hormone-refractory prostate cancer given paclitaxel/estramustine/carboplatin for weeks 1, 2, and 3 of a 4-week cycle.

Patients and Methods

Eighty-four patients were registered into the trial. Paclitaxel 80 mg/m2 and carboplatin area under the curve of 2 were administered intravenously on days 2, 9, and 16, and oral estramustine 280 mg 3 times daily was given on days 1-3, 8-10, and 15-17 for 6 cycles. Eastern Cooperative Oncology Group performance status 0, 1, and 2 was 46%, 41%, and 13%, respectively, and median age was 70 years (range, 53-82 years), with 58 patients (69%) aged > 65 years. The majority of patients (83%) were white. Fifteen patients (18%) had received previous chemotherapy, 61 patients (73%) had undergone previous surgery, and 51 patients (61%) had received previous external-beam radiation therapy.

Results

Intent-to-treat analysis revealed a ≥ 50% prostate-specific antigen decrease rate of 61%. Median survival was 15.3 months. The most frequent grade ≥ 3 toxicities included fatigue (11%), nausea (10%), neutropenia (9%), anemia (6%), and vomiting (6%).

Conclusion

Paclitaxel/estramustine/carboplatin administered in a weekly regimen is highly effective in the treatment of hormone-refractory prostate cancer and can be administered with reasonable safety in an outpatient setting.  相似文献   
999.
1000.
Thrombophilia has been described to be involved in the pathogenesis of idiopathic recurrent miscarriage (IRM). We investigated the association between IRM and a C-->T polymorphism at nucleotide 46 in the 5'-untranslated region of the coagulation factor XII (FXII) gene. Two hundred and twelve women with a history of IRM and 149 healthy controls were tested by a mutagenically separated polymerase chain reaction assay (MS PCR). Allele and genotype frequencies were not significantly different between the study and the control groups. Our data suggest that the FXII gene is not a candidate gene for this condition.  相似文献   
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