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51.
Rabinowitz  J; Petros  WP; Stuart  AR; Peters  WP 《Blood》1993,81(9):2452-2459
Endogenous cytokines are thought to mediate numerous biologic processes and may account for some adverse effects experienced following the administration of recombinant proteins. This study describes the pattern of endogenous cytokine exposure following high-dose chemotherapy. Blood concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), macrophage colony-stimulating factor (M-CSF), and erythropoietin (EPO) were measured by enzyme-linked immunosorbent assay (ELISA) methods in 68 patients receiving the same ablative chemotherapy regimen (cyclophosphamide, cisplatin, carmustine). Patients were grouped according to cellular support (autologous bone marrow [BM] CSF-primed peripheral blood progenitor cells [PBPCs]) and prescribed growth factor (recombinant human granulocyte or granulocyte-macrophage colony-stimulating factor [rHuG- CSF or rHuGM-CSF]). Leukocyte reconstitution was most accelerated in the groups treated with PBPCs and rHuG-CSF. IL-6, M-CSF, and TNF-alpha concentrations were higher in the groups treated with rHuGM-CSF and without PBPCs. Maximal endogenous cytokine concentrations occurred approximately 12 days after BM reinfusion. High concentrations of EPO occurred in patients experiencing significant hypotension despite routine transfusions for hematocrit < 42%. High M-CSF and IL-6 levels were associated with increased platelet transfusion requirements. Concentrations of all four cytokines were significantly higher in patients experiencing renal or hepatic toxicity, with elevations occurring in a predictable sequence and M-CSF elevations occurring first. This report shows that endogenous cytokine concentrations may be influenced by either cellular or CSF support and are associated with differences in platelet reconstitution and organ toxicity.  相似文献   
52.
Oral health is receiving increased recognition as an important factor for the health of women and children. This article describes pathological oral conditions and the physiological mechanisms involved in the maintenance of oral health during illness and hospitalization, including the importance of the production and secretion of adequate saliva. Alterations in physiology of saliva induced by hormonal changes that occur during pregnancy are described along with possible roles in pathophysiological conditions associated with pregnancy. The roles of xerostomia and periodontal disease as sources of pathological bacteria involved in aspiration pneumonia, ventilator-associated pneumonia, and chronic inflammation are described. The bidirectional interaction between oral health and general overall health is described, with special emphasis on cardiovascular disease. Specific evidence-based nursing measures to reduce the complications associated with poor oral health in at-risk patients are provided.  相似文献   
53.
空间位阻、对空气稳定的单氧氯化膦与Pd2(dba)3反应原位形成复合物,可促进芳基硼酸与芳基卤的Suzuki交叉偶联反应。芳基卤上有吸电子基时反应性更高,羰基及氰基无需保护。13例收率66%~93%。  相似文献   
54.
Anesthesia practitioners have begun to focus on the immune function of their patients as more research is done on the interface between anesthesia, surgery, and immune alterations. The anxiety associated with anesthesia and surgery produces alterations in immune function through several mechanisms which affect recovery from surgery and wound healing. Immune status may be assessed by traditional measures such as complete blood count and differential as well as using newer technologies such as flow cytometry, lymphocyte proliferation assays and natural killer cell cytotoxicity. Anxiety produces immune changes through sympathetic adrenal medullary and hypothalamic pituitary adrenal cortical mechanisms, as well as through the neurotransmitter substance P. Anxiety also produces changes in immune function through alteration in health behaviors such as increased smoking, increased alcohol consumption, drug use, and changes in diet and sleep. Recommendations for psychological and pharmacological measures that are effective in reducing stress-induced immunosuppression among this group of patients are provided. The future use of substance P antagonists, which are currently under investigation, as well as cytokine manipulation, hold promise for further measures to reduce immune alterations associated with anxiety.  相似文献   
55.
余晓林  程鹏远  刘红  陈万平  朱华锋 《医学争鸣》2005,26(18):1720-1721
目的:研究慢性肝炎患者HBV-DNA水平与病情变化的关系. 方法:采用荧光标记定量PCR的方法,测定慢性乙型肝炎急性发作患者(HBeAg阳性45例,抗HBe阳性30例)其活动期和恢复期的血清HBV-DNA含量. 结果:HBeAg阳性组血清HBV-DNA含量(Logarrithm copy/mL)在活动期显著高于恢复期[(10.2±1.6) vs (5.3±2.1), P<0.05],抗-HBe阳性组血清HBV-DNA含量(Logarrithm copy/mL)在活动期显著高于恢复期[(7.6±1.3) vs (4.0±2.0), P<0.05]. 另外,活动期血清HBV-DNA含量(Logarrithm copy/mL)在HBeAg阳性组显著高于抗HBe阳性组[(10.2±1.6) vs (7.6±1.3), P<0.05]. 血清HBV-DNA水平与丙氨酸转氨酶(ALT)、门冬氨酸转氨酶(AST)及总胆红素(T-BLLI)之间无相关性. 结论:HBV-DNA复制水平与慢性乙型病毒性肝炎的活动密切相关.  相似文献   
56.
The ability to isolate DNA from archived human serum, plasma and paraffin-embedded human tissues enhances opportunities to study breast, lung and other cancer risk factors. We report herein a simple and fast protocol for the extraction of genomic DNA from these sources. Using a phenol-based extraction method, the recovery for DNA is quantitative and reproducible. DNA yields in serum (250 microl) were between 162 and 1060 ng (n = 18 subjects), in plasma (250 microl) were between 165 and 375 ng (n = 5 subjects) and in embedded tissues (5-microm thick sections for ethanol fixed, and between 5- and 20-microm sections for formaldehyde fixation) were between 1 microg and 11.7 microg (n = 32 subjects). The extraction method was combined with newly designed PCR- based assays for cancer susceptibility marker genes such as CYP1A1 (exon 7), CYP2E1 (Dra1, Rsa1), GSTM1 and NAT2 [NAT2*5A (C481T), NAT2*6A (G590A), NAT2*7A (G857A)]. Genotyping results from the serum and paraffin-embedded tissues compared favorably to results from archived freshly frozen tissues, where concordance was 98% for serum, 100% for ethanol-fixed embedded tissues, and 97% for formaldehyde-fixed and paraffin-embedded tissues. This facile method will allow for the use of archived tissue samples of prospective cohort and other studies where intact DNA was not previously available.   相似文献   
57.
In mammals, one of the Mad homologues, Smad2, was reported to be a mediator of TGF-beta signaling, and was found mutated in some cases of colon and lung cancers. To extend the analysis of this gene, we previously investigated the genomic organization of the human Smad2 gene and defined the structure of 12 exons and flanking introns. In this study, we designed 11 sets of intron-based primers to examine the entire coding region of the Smad2 gene. By the PCR-SSCP method using these primers, we screened genomic DNA sequences of colorectal cancers for mutations of the Smad2 gene. Though there was no mutation within all exons of the Smad2 gene, two of 60 sporadic colorectal cancers displayed deletions in the polypyrimidine tract preceding exon 4. Deletions of this region were also detected in colon cancer cell lines, and were clustered within cells exhibiting microsatellite instability. Deletions in the polypyrimidine tract had various effects on pre-mRNA splicing, but had no effect on the splicing of the Smad2 gene in these cases. However, our data support the idea that the polypyrimidine tract in the splicing acceptor site is a target of mutations in mismatch repair-deficient tumors.   相似文献   
58.
血管性痴呆发病机制研究进展   总被引:19,自引:0,他引:19  
石苗茜  刘卫平 《医学争鸣》2007,28(9):860-863
血管性痴呆发病率日益增高, 但发病机制不明确, 缺乏有效治疗手段, 因此各方面研究日益受重视, 本文主要对血管性痴呆的危险因素、病理类型、发病机制等方面做一综述.  相似文献   
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