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1.
Optimal use of interferons (IFNs) for the treatment of tumor disease requires experimental work in order to precisely define IFN actions. We have pointed out three modes of such actions relevant for the antitumor efficacy exerted by IFNs: effects on apoptosis, effects on genes involved in malignant transformation and effects on angiogenesis. These are but three selected areas forming a basis for the development of optimal IFN therapy. Further experimental work, undertaken in these and additional IFN areas, is mandatory for the most effective clinical use of IFNs for the treatment of tumor disease.  相似文献   
2.
The sex pheromone emitted by the female oleander scale, Aspidiotus nerii (Homoptera, Diaspididae), has been isolated and characterized as (1R, 2S)-cis-2-isopropenyl-1-(4'-methyl-4'-penten-1'-yl)cyclobutaneethanol acetate by using advanced MS and NMR spectroscopic methods, as well as a variety of microderivatization sequences. The structure has been confirmed by stereo- and enantioselective synthesis of the four possible stereoisomers. The absolute configuration has been determined by comparison of the activity of the cis (1S,2R) and (1R, 2S) enantiomers with that exhibited by the natural material in greenhouse bioassays and field tests. The structure of this sesquiterpenoid pheromone is new in the coccids and in the pheromone field in general.  相似文献   
3.
Studied characteristics of expertise in situations where judges deal with multidimensional information. Psychometric criteria were advocated as being indicative of expert judgment: (a) Experts should tend to cluster variables in the same way when identifying and organizing cues; (b) expert judgment should be highly reliable (intrajudge reliability), show both convergent and discriminant validity, and be relatively free of judgmental bias when measuring cues; and (c) experts should weight and combine information in similar ways. These criteria were applied to data obtained when 3 medical pathologists rated the amount of histological signs in biopsy slides. Results show that these experts generally met the criteria, although they did not seem to weigh information similarly. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
BACKGROUND: The characterization of the genes encoding melanoma-associated antigens MART-1 or gp100, recognized by T cells, has opened new possibilities for the development of immunization strategies for patients with metastatic melanoma. With the use of recombinant adenoviruses expressing either MART-1 or gp100 to immunize patients with metastatic melanoma, we evaluated the safety, immunologic, and potential therapeutic aspects of these immunizations. METHODS: In phase I studies, 54 patients received escalating doses (between 10(7) and 10(11) plaque-forming units) of recombinant adenovirus encoding either MART-1 or gp100 melanoma antigen administered either alone or followed by the administration of interleukin 2 (IL-2). The immunologic impact of these immunizations on the development of cellular and antibody reactivity was assayed. RESULTS: Recombinant adenoviruses expressing MART-1 or gp100 were safely administered. One of 16 patients with metastatic melanoma receiving the recombinant adenovirus MART-1 alone experienced a complete response. Other patients achieved objective responses, but they had received IL-2 along with an adenovirus, and their responses could be attributed to the cytokine. Immunologic assays showed no consistent immunization to the MART-1 or gp100 transgenes expressed by the recombinant adenoviruses. High levels of neutralizing antibody were found in the pretreatment sera of the patients. CONCLUSIONS: High doses of recombinant adenoviruses could be safely administered to cancer patients. High levels of neutralizing antibody present in patients' sera prior to treatment may have impaired the ability of these viruses to immunize patients against melanoma antigens.  相似文献   
5.
PURPOSE: To compare standard therapy with bleomycin, etoposide, and cisplatin (BEP) to experimental therapy with etoposide, ifosfamide, and cisplatin (VIP) as primary treatment of men with advanced, disseminated germ cell tumors. PATIENTS AND METHODS: A total of 304 men with advanced disseminated germ cell tumors were randomly allocated to receive four courses of BEP or VIP. Two hundred ninety-nine patients were assessable for toxicity and 286 were assessable for response. Complete response rates, favorable response (complete remission, surgical free of disease, continuous partial remission for 2+ years), time to treatment failure, and overall survival were assessed. RESULTS: Overall complete remission rate (VIP, 37%; BEP, 31%), favorable response rate (VIP, 63%; BEP, 60%), failure-free at 2 years (VIP, 64%; BEP, 60%), and 2-year overall survival (VIP, 74%; BEP, 71%) were not significantly different between the two treatments. Grade 3 or worse toxicity, particularly hematologic and genitourinary toxicity, was significantly more common in patients who received VIP. CONCLUSION: BEP and VIP produce comparable favorable response rate and survival in patients with poor-risk germ cell tumors. The substitution of ifosfamide for bleomycin, however, was associated with significantly greater toxicity. Four courses of BEP remain the standard treatment for advanced disseminated germ cell tumors.  相似文献   
6.
BACKGROUND: The mechanism behind the antiviral action of interferon (IFN) therapy in chronic hepatitis C virus (HCV) infection is not well understood, and, furthermore, few factors have been shown to be good predictors of a favourable response to IFN treatment in chronic HCV infection. METHODS: Freshly explanted liver cells and peripheral blood mononuclear cells (PBMC) from 80 patients with chronic HCV infection were used to study the capacity of IFN to induce the enzyme 2',5'-oligoadenylate synthetase (2'5'-AS) in vitro. The HCV genotype was determined in 53 patients. The induction of 2'5'-AS was correlated to the results of IFN-alpha treatment in 36 patients. RESULTS: Normalization of transaminases during IFN treatment was significantly associated with 2'5'-AS levels in liver cells cultured in the absence of IFN. A similar tendency, although not statistically significant, was found for IFN-induced levels of 2'5'-AS in liver cells. No such associations were found when PBMC were analysed. Six patients showed a sustained biochemical response. These six did not deviate significantly from the remaining patients with regard to base-line or IFN-induced levels of 2'5'-AS in liver cells or PBMC. Eradication of HCV RNA during IFN treatment did not correlate with 2'5'-AS levels in liver cells. Comparison of HCV genotype and clinical response showed that patients with genotype 3a had the most favourable outcome. No association was found between liver histology and treatment outcome. CONCLUSION: These data imply that direct effects of IFN on liver cells are of importance for the response to IFN treatment.  相似文献   
7.
Results of irradiation, 1 to 3 years after treatment, are presented in 64 cases of nasopharyngeal carcinoma in East Africans. Two types of anatomic point indices are presented. Both correlate well with the results. Prophylactic irradiation of the mediastinum and both axillae was not followed by any evident improvement of the results.  相似文献   
8.
9.
A restriction fragment length polymorphism (RFLP) analysis of the alpha- and beta-interferon (IFN) genes was performed in malignant cells from 52 patients with acute lymphocytic leukemia (ALL). Normal cell DNA was available for comparison in 23 of the patients. Ten patients were found to have gross alterations of their alpha- and beta-IFN genes. Leukemic cells from 2 ALL patients showed a complete loss of alpha- and beta-IFN genes. Seven patients had a hemizygous loss of one of the alpha- and beta-IFN alleles, as shown by RFLP analysis and/or loss of signal intensity. In one other patient the malignant clone was reduced to homozygosity with regard to the alpha- and beta-IFN genes, without loss of signal intensity. In patients without hemizygous deletions, the overall incidence of complete homozygosity for the alpha- and beta polymorphisms was higher than expected. Analysis of the data indicates that the total frequency of ALL clones with gross alterations of the IFN-loci is around 30%. A 9p24 probe detected hemizygous deletions in 2 cases of IFN gene deletions. In the other tested cases the deletions were interstitial. No deletions of 9p24 were detected in patients without allelic losses of IFN genes. In 5 cases of allelic IFN gene deletions, DNA from parents was available for comparison. In 4 cases the deleted allele was derived from the mother, whereas in the fifth it originated from the father. Pediatric ALL patients with IFN-gene deletions or homozygosity for all polymorphisms in the IFN-loci had a significantly worse prognosis than heterozygotes. We conclude that deletion of alpha- and beta-IFN genes is a relatively common event in ALL and that RFLP analysis of the IFN genes may provide additional prognostic information in childhood ALL. Whether or not the IFNs act as tumor-suppressor genes in this disease is not yet known.  相似文献   
10.
The paper considers the prediction of reliability for a complex system designed for continuous operation. The state of the system is defined by identifying the subsystems which are functioning, the remainder undergoing repair (no inactive standby). The system is described as up whenever it is in one of an arbitrarily selected set of the system states. It is assumed that maintenance facilities are always adequate, and that the system conforms to a few other very mild restrictions. An exponential failure law is not assumed. Formulas are developed giving the mean durations of system up-times and down-times in terms of the corresponding quantities for the subsystems. The sensitivities of the formulas to errors in the input data are considered.  相似文献   
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