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71.
BACKGROUND: An eight-hour workshop was conducted at a professional meeting in 1996 to introduce medical faculty to the principles of continuous quality improvement (CQI) as they relate to change in medical education and to provide participants with opportunities to use specific tools for applications to education. Four two-hour sessions focused on an introduction to CQI, understanding and mapping processes, identifying change ideas, and testing a change for improvement. TESTING A CHANGE FOR IMPROVEMENT: The goals of the final session were to plan a pilot test of an improvement, identify the steps of the plan-do-study-act (PDSA) cycle, and consider change for improvement in the context of one's own organization. Working in small groups, participants chose a specific change one might try in the following example: improving student performance in a neuroscience course. POSTSESSION EVALUATION AND FOLLOW-UP: Immediately following the workshop sessions, participants represented by administrators in medical education and clinical and basic science teaching faculty completed evaluations on the usefulness and likelihood of their using CQI tools. One year later, of the 32 workshop registrants who were mailed surveys, 15 respondents rated their change in understanding of CQI and their use of CQI techniques. More than 60% of the respondents reported application of CQI principles at their organizations. CQI methods used most frequently included structured team meetings, prioritizing opportunities, and brainstorming. CONCLUSION: The significant application of CQI principles and methods reported by participants one year after a brief intervention supports a need and utility for CQI principles and tools in medical education.  相似文献   
72.
1. The synthesis and release of nitric oxide may play a role in the pathogenesis of peripheral vasodilatation and hyperdynamic circulation observed in liver cirrhosis. In this work, we analysed the synthesis of nitric oxide by the lympho-mononuclear cells of peripheral blood from patients with chronic alcoholic and non-alcoholic liver disease and we identified the isoform of nitric oxide synthase involved in the increased nitric oxide synthesis. 2. Patients were classified following clinical and histological criteria in non-alcoholic cirrhotic, alcoholic cirrhotic and non-cirrhotic chronic liver disease. We studied clinical and analytical characteristics, haemodynamic parameters and endotoxin levels in these patients. 3. Cirrhotic patients showed an increase of cardiac output and a decrease of peripheral vascular resistance. These patients had higher levels of plasma endotoxin than those observed in the control group. N omega-Nitro-L-arginine methyl ester (L-NAME)-inhibitable nitrite production from mononuclear lymphocyte cells was higher in patients than in the control group, the highest levels being in non-alcoholic cirrhotic patients, and the lowest levels in patients with non-cirrhotic alcoholic liver disease. 4. Immunocytochemistry studies revealed a positive immunoreactivity for the inducible isoform of nitric oxide synthase in lympho-mononuclear cells that was more evident in non-alcoholic than in alcoholic cirrhotic patients. By Northern blot, inducible nitric oxide synthase mRNA expression was observed only in lymphomononuclear cells from non-alcoholic cirrhotic patients. 5. Our patients show a correlation between nitric oxide synthesis, endotoxin levels and haemodynamic parameters. 6. These findings indicate that lympho-mononuclear cell stimulation may play a role in elevated nitric oxide production in hepatic cirrhosis. Thus, this increased nitric oxide synthesis could be implicated in the pathogenesis of the haemodynamic disturbances frequently found in cirrhotic patients. This increase seems to be induced, at least in part, by activation of an inducible isoform of nitric oxide synthase.  相似文献   
73.
OBJECTIVE: To estimate the potential direct cost of making triple combination antiretroviral therapy widely available to HIV-positive adults and children living in countries throughout the world. METHODS: For each country, antiretroviral costs were obtained by multiplying the annual cost of triple antiretroviral therapy by the estimated number of HIV-positive persons accessing therapy. Per capita antiretroviral costs were computed by dividing the antiretroviral costs by the country's total population. The potential economic burden was calculated by dividing per capita antiretroviral costs by the gross national product (GNP) per capita. All values are expressed in 1997 US dollars. RESULTS: The potential cost of making triple combination antiretroviral therapy available to HIV-positive individuals throughout the world was estimated to be over US$ 65.8 billion. By far the greatest financial burden was on sub-Saharan Africa. The highest per capita drug cost in this region would be incurred in the subregions of Southern Africa (US$ 149) followed by East Africa (US$ 116), Middle Africa (US$ 44), and West Africa (US$ 42). In the Americas, subregional data indicated the highest per capita drug cost would be in the Latin Caribbean (US$ 22), followed by the Caribbean (US$ 17), Andean Area (US$ 7), the Southern Cone (US$ 6), North America (US$ 6), and Central American Isthmus (US$ 5). In Asia and Europe the percentage of the GNP necessary to finance drug therapy was less than 1% in most countries examined. CONCLUSION: Our results demonstrate that the cost of making combination antiretroviral therapy available worldwide would be exceedingly high, especially in countries with limited financial resources.  相似文献   
74.
Tyrosine-114 is one of 13 totally conserved amino acids in all known sequences of O6-alkylguanine-DNA alkyltransferase (AGT). The importance of this amino acid in repair of alkylated DNA by AGT was studied by changing it to phenylalanine (F), alanine (A), threonine (T), or glutamic acid (E) in human AGT. The activities of the mutant proteins were then compared to those of the wild type with regard to abilities to do the following: (a) protect Escherichia coli from the methylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG); (b) repair methylated DNA in vitro; (c) bind to oligodeoxynucleotides containing O6-methylguanine; and (d) react with the low molecular weight pseudosubstrate, O6-benzylguanine. When expressed at high levels in E. coli strain GWR109, lacking endogenous AGT, the wild type and the Y114F mutant were highly effective in reducing mutations and cell killing by MNNG. The Y114A mutant had a much smaller protective effect, and mutants Y114T and Y114E were inactive. Purified preparations of all four AGT mutants showed an approximately similar degree (74-120-fold) of reduction in the rate of reaction with O6-benzylguanine. In contrast, the degree of reduction in activity toward methylated DNA substrates in vitro varied according to the mutation with the more conservative Y114F producing only a 30-fold reduction and the most drastic change of Y114E abolishing activity completely. Alteration Y114A produced a 1000-fold reduction whereas Y114T reduced activity by 10000-fold. All of the mutations affected the binding of AGT to single- or double-stranded oligodeoxynucleotides containing O6-methylguanine. The extent of increase in the Kd varied according to the amino acid with 2-5-fold (F), 7-11-fold (A), 167-200-fold (T), and 600-1000-fold (E) increases. These results are consistent with tyrosine-114 playing a role both in the binding of AGT to its DNA substrate and in facilitating the transfer of the alkyl group. It is probable that AGT resembles other DNA repair proteins in bringing about a "flipping out" of the target base from the DNA helix. Tyrosine-114 is therefore an excellent candidate for a key role in the interaction with the flipped O6-methylguanine. The results also show that when large amounts of AGT are produced in the cell, substantial decreases in the efficiency with which AGT can repair methylated DNA do not prevent the ability to protect E. coli from toxic alkylating agents. Mutant Y114F, whose activity was reduced by 30-fold, was equal to wild-type AGT in bringing about this protection.  相似文献   
75.
This study will evaluate the safety and efficacy of allogenic donor lymphocyte infusions in patients who have relapsed hematologic malignancies after allogeneic bone marrow transplantation (BMT). Donor lymphocyte transfusions have resulted in the cure of some patients with relapsed leukemia or lymphoproliferative disorder after allogeneic BMT, but has been complicated by the development of graft versus host disease (GvHD). We hypothesize that a retroviral vector containing the Herpes simplex thymidine kinase (HStk) gene will allow for retention of the anti-leukemia response of transfused donor lymphocytes while allowing for the adverse effects of GVHD to be mitigated. Patients with relapsed hematologic malignancies after allogeneic BMT will be infused with ex vivo gene modified donor lymphocytes. The Herpes Simplex thymidine kinase (HStk) gene will be transduced into the cells ex vivo using LTKOSN. 1 vector supernate. Insertion of the HStk gene into lymphocytes confers a sensitivity to the anti-herpes drug ganciclovir (GCV). This selective destruction of donor lymphocytes in situ will be used to abrogate the effect of graft versus host disease, if it develops.  相似文献   
76.
77.
A discussion is carried out about the experiences with the application of rimantadine and amantadine to patients with influenza. The basic general results consisted in the fact that 2 of the 74 patients treated had a high cure percent (> 68.0%) within the first 72 hours after using the drug. No new diseased were found among the 40 contacts to whom chemoprophylaxis was applied. There were only 3.9% adverse reactions among the total number of people treated with amantadine.  相似文献   
78.
We have previously described an in vitro sensitization (IVS) procedure which enabled the generation of therapeutic T cells from tumor-bearing mice for adoptive immunotherapy. The procedure involved culture of tumor-draining lymph node (TDLN) cells with irradiated tumor in the presence of interleukin-2 (IL-2). The availability of many recombinant cytokines affords an opportunity to examine their effects on the immune response to tumor. In this study, we investigated the effect of tumor necrosis factor-alpha (TNF alpha) on the generation and function of IVS cells utilized in adoptive immunotherapy of the murine MCA 106 sarcoma. TNF alpha administered iv at nontherapeutic doses was found to enhance the antitumor efficacy mediated by IVS cells plus IL-2 in the treatment of pulmonary metastases. In contrast, TNF alpha administration to mice bearing progressive footpad tumors had inhibitory effects on the sensitization of tumor-reactive cells in TDLN since IVS cells generated from these animals displayed a diminished antitumor effect. This effect appeared to be due to a reduced number of tumor-reactive lymphoid cells in the TDLN since TNF alpha added to IVS cultures did not alter the antitumor efficacy of the resultant IVS effector cells. These findings indicate the divergent effects of TNF alpha on the immune response to tumor and adoptive immunotherapy with IVS cells.  相似文献   
79.
BACKGROUND: An erythrocyte sedimentation rate (ESR) of at least 40 mm/h is considered an important requisite for the diagnosis of polymyalgia rheumatica (PMR). However, the relative frequency and clinical features of PMR in patients without a significantly increased ESR are unclear. METHODS: We performed a retrospective study of patients diagnosed as having PMR at the rheumatology divisions of 3 teaching hospitals. The diagnosis of PMR was established, regardless of the ESR, in 201 consecutive patients fulfilling the following criteria: (1) age 50 years or older, (2) severe proximal pain for more than 1 month in at least 2 of 3 areas: neck, shoulder, and/or pelvic girdles, and (3) rapid resolution of the syndrome while taking low-dose prednisone. Patients with giant cell arteritis were previously excluded from the study. The frequency and clinical features of patients with PMR and an ESR lower than 40 mm/h were analyzed. A comparative study between these patients and those with high ESRs was performed. RESULTS: An ESR lower than 40 mm/h was found in 41 patients (20.4%). These patients were younger (P = .02), were more frequently men (P = .006), and experienced a lower frequency of fever (P = .003) and weight loss (P = .07). Furthermore, these patients were characterized by an absence of anemia (P = .002) and a lower frequency of abnormal protein electrophoresis results (P < .001). Otherwise, their clinical syndrome, response to therapy, and frequency of relapses were similar to those of patients with classic PMR. In the entire population of 201 patients, the ESR was related to the length of treatment, number of areas involved, presence of fever, weight loss, and laboratory test result abnormalities, but it was unrelated to the duration of the illness prior to diagnosis. CONCLUSIONS: It is not uncommon to find a patient with PMR with an ESR lower than 40 mm/h. This syndrome is more frequent in men and it is clinically less severe than the classic form of PMR. Its recognition will allow these patients to benefit from an effective treatment with low-dose corticosteroids.  相似文献   
80.
Autonomic dysreflexia (AD) is a characteristic syndrome that occurs in spinal cord injury (SCI) patients with lesions above the sympathetic outflow at T6 and rarely in those with lesions below T10. Symptoms are initiated by noxious stimuli below the level of injury which result in massive sympathetic discharges from the isolated cord. These produce what may be called a sympathetic storm manifest by severe life threatening hypertension. Anesthesiologists and surgeons dealing with SCI patients must know how to recognize this syndrome, how to prevent its occurrence and how to manage it aggressively. Choice of anesthesia is frequently difficult and, in particular, it may be difficult to decide which type of anesthesia is best for patients susceptible to the syndrome. Therefore, we have conducted a retrospective study of SCI patients in the Department of Veterans Affairs Medical Center, Long Beach, California, where the Spinal Cord Injury Service is one of the largest in the country.  相似文献   
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