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31.
The treatment of malignant histiocytosis   总被引:1,自引:0,他引:1  
Twenty-four consecutive cases of malignant histiocytosis (MH) treated at Stanford Medical Center between 1973 and 1983 have been reviewed. Most patients presented with systemic symptoms (91%) and advanced disease (stage IV, 80%). Multiple organ involvement was common. In six cases, pathologic tissue was further characterized by frozen section immune histochemistry, using a panel of monoclonal antibodies known to react with monocytes and macrophages, as well as a variety of hematopoietic cells. One case expressed a mature monocyte/macrophage phenotype; three cases were considered null cell or primitive lesions; and two cases were identified as probable T cell lymphomas. Seven patients underwent splenectomy. Two patients died prior to any treatment. Twenty-two patients were treated with CHOP (cyclophosphamide, Adriamycin, vincristine, prednisone) +/- bleomycin (B), +/- midcycle high-dose methotrexate (HD-MTX) with leucovorin rescue. Seven patients received prophylactic intrathecal MTX. Of 22 evaluable patients, there was a 68% complete response rate (CR), a 23% partial response rate (PR), and a 9% no response rate (NR). Median duration of CR was 30+ months; median duration of PR was 2.4 months. Median survival for patients attaining a CR has not been reached v 3 months for the PR and NR groups. For all 24 patients, median survival was 2 years, with a 5-year actuarial survival of 40%. Multivariate analysis revealed that a platelet count less than 150,000 (P Cox = .005) and the dose of drug delivered (P Cox = .057) were the most important prognostic factors. Prophylactic intrathecal MTX therapy and splenectomy did not influence survival. Although MH is an aggressive disease with a poor prognosis, it is potentially curable. Systematic and aggressive treatment should further improve the outcome.  相似文献   
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33.
AIM: To characterize peculiarities of arterial hypertension course in citizens of sieged Leningrad. MATERIALS AND METHODS: 2000 case records of hypertensive patients treated in 6 hospitals of sieged Leningrad have been analysed. RESULTS: Arterial hypertension (AH) was verified as the basic disease in 69 cases. Of them, only 47 patients were eligible for analysis. Mean age of the patients was 45 years. AH duration before hospitalization was less than 1 year in 35% of the cases. Hypertensive crises, hypertensive angiopathy, cerebral atherosclerosis, cardiac hypertrophy were documented in 25, 15, 15 and 64% of the cases, respectively. In hospital, no specific antihypertensive therapy was given. At the discharge, systolic blood pressure decreased significantly, diastolic blood pressure decreased insignificantly. CONCLUSION: Clinical data evidence for rapid affection of target organs in hypertensive subjects exposed to unfavourable conditions of the war time.  相似文献   
34.
Upon translation of poliovirus RNA in reticulocyte lysates, initiation occurs largely "incorrectly," that is, at sites in the middle of the viral genome rather than at the beginning of the polyprotein reading frame; the anomaly appears to be due to an initiation factor deficiency. Here, a fraction which stimulated initiation at the correct site, provisionally called "initiation correcting factor" (ICF), was partially purified from Krebs-2 cells. The ICF activity appeared to copurify with a complex of initiation factors eIF-2 and eIF-2B. The ability of ICF to stimulate, in reticulocyte lysates, the correct initiation of translation on the RNAs from neurovirulent and attenuated type 1 and type 3 poliovirus strains was investigated. Like crude initiation factor preparations, ICF appeared to be relatively less active with the RNAs from attenuated strains, the difference being especially pronounced for the type 3 strains. For the latter strains, the data suggested an important role of the nucleotide at, and perhaps around, position 472 in determining a response to the addition of ICF. It is proposed that interaction of a specific segment of the viral RNA with one or more of initiation factors plays an important part in the mechanism of translation of the picornavirus genomes, poliovirus attenuation, and, possibly, pathogenesis of poliomyelitis.  相似文献   
35.

Introduction  

Previous meta-analyses of magnesium sulphate infusion in the treatment of aneurysmal subarachnoid hemorrhage (SAH) have become outdated due to recently published clinical trials. Our aim was thus to perform an up-to-date systemic review and meta-analysis of published data on the use of magnesium sulphate infusion in aneurysmal SAH patients.  相似文献   
36.
人胰腺α-淀粉酶的cDNA克隆和原核表达的初步研究   总被引:4,自引:0,他引:4  
目的 获得人胰腺α-淀粉酶(AMY2A)基因并进行原核表达。方法 采用基因工程技术,根据人AMY2A基因序列设计并合成特异性引物;从人胰腺组织中提取总RNA,反转录成CDNA第一链;逆转录-聚合酶链反应(RT-PCR)扩增人胰腺AMY2A基因,经BamH Ⅰ和Kpn Ⅰ双酶切、连接并插入原核表达载体pGEX-5T,构建pGEX-5T-AMY2A重组表达载体,在大肠杆菌BL21中异丙基硫代半乳糖苷酶(IPTG)诱导表达AMY2A蛋白。包涵体经尿素变性、复性及谷胱苷肽琼脂糖柱亲和层析纯化、AMY2A酶活性测定和免疫印迹分析。结果 重组质粒测序和酶切结果显示AMY2A基因已正确插入pGEX-5T,重组蛋白、复性及纯化产物SDS聚丙烯酰胺凝胶电泳(SDS-PAGE)在84 000处有一条明显的蛋白表达条带,AMY2A检测具有酶活性,免疫印迹分析表明重组蛋白具有人胰腺淀粉酶抗原性。结论 作者已克隆并在大肠杆菌中初步表达并获得纯化的谷胱苷肽转移酶(GST)-AMY2A融合蛋白。  相似文献   
37.
In this study, we assessed the activity of ciprofloxacin, levofloxacin, sparfloxacin, and trovafloxacin against clinical isolates of Streptococcus pneumoniae that were resistant to the less-recently developed fluoroquinolones by using defined amino acid substitutions in DNA gyrase and topoisomerase IV. The molecular basis for resistance was assessed by using mutants selected with trovafloxacin, ciprofloxacin, and levofloxacin in vitro. This demonstrated that the primary target of trovafloxacin in S. pneumoniae is the ParC subunit of DNA topoisomerase IV, similar to most other fluoroquinolones. However, first-step mutants bearing the Ser79-->Phe/Tyr substitution in topoisomerase IV subunit ParC were susceptible to trovafloxacin with a minimum inhibitory concentration of 0.25 microg/ml, and mutations in the structural genes for both topoisomerase IV subunit ParC (parC) and the DNA gyrase subunit (gyrA) were required to achieve levels of resistance above the breakpoint. The data also suggest that enhanced activity of trovafloxacin against pneumococci is due to a combination of factors that may include reduced efflux of this agent and an enhanced activity against both DNA gyrase and topoisomerase IV.  相似文献   
38.
介绍了吉安电视台全硬盘自动播出网络系统设计指导思想及系统构成,该系统采用网络技术实现资源共享,采用多级安全措施确保安全播出.  相似文献   
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40.
Eukaryotic translation initiation begins with ribosomal recruitment of aminoacylated initiator tRNA (Met-tRNAMeti) by eukaryotic initiation factor eIF2. In cooperation with eIF3, eIF1, and eIF1A, Met-tRNAMeti/eIF2/GTP binds to 40S subunits yielding 43S preinitiation complexes that attach to the 5′-terminal region of mRNAs and then scan to the initiation codon to form 48S initiation complexes with established codon–anticodon base-pairing. Stress-activated phosphorylation of eIF2α reduces the level of active eIF2, globally inhibiting translation. However, translation of several viral mRNAs, including Sindbis virus (SV) 26S mRNA and mRNAs containing hepatitis C virus (HCV)-like IRESs, is wholly or partially resistant to inhibition by eIF2 phosphorylation, despite requiring Met-tRNAMeti. Here we report the identification of related proteins that individually (Ligatin) or together (the oncogene MCT-1 and DENR, which are homologous to N-terminal and C-terminal regions of Ligatin, respectively) promote efficient eIF2-independent recruitment of Met-tRNAMeti to 40S/mRNA complexes, if attachment of 40S subunits to the mRNA places the initiation codon directly in the P site, as on HCV-like IRESs and, as we show here, SV 26S mRNA. In addition to their role in initiation, Ligatin and MCT-1/DENR can promote release of deacylated tRNA and mRNA from recycled 40S subunits after ABCE1-mediated dissociation of post-termination ribosomes.  相似文献   
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