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71.
人参皂甙Rg1对老年大鼠免疫功能的调节作用 总被引:23,自引:1,他引:22
已知老年机体免疫功能的降低与淋巴细胞增殖能力的减弱和白细胞介素-2(IL-2)产生减少有密切关系。以老年大鼠免疫功能为主要研究对象,首次发现人参皂甙Rg1无论体内给药还是体外实验均能选择性增强老年大鼠脾淋巴细胞增殖能力和IL-2的产生与释放,采用Northern和Western印迹分析法证明,Rg1可明显促进IL-2基因和蛋白的表达,表现在IL-2mRNA和IL-2蛋白含量的显著增加。值得注意的是,在同样的条件下,Rg1对青年大鼠免疫功能的影响并不显著,由此可以认为Rg1一种“免疫调节剂”,而并非单纯的“免疫增强剂”。 相似文献
72.
D. van Zoeren-Grobben JHN Lindeman E. Houdkamp RMW Moison JT Wijnen HM Berger 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(12):1356-1362
Markers of oxidative stress and antioxidant activity in plasma and erythrocytes were studied for 14 d after birth in infants with neonatal respiratory distress syndrome ( n = 9) and controls ( n = 36). In plasma, the total radical trapping antioxidant capacity and the chain-breaking antioxidants vitamin C, sulfhydryl groups and bilirubin were similar. The differences in uric acid levels were not consistent, but vitamin E levels and vitamin E/total-lipid ratio were lower in the neonatal respiratory distress group ( p < 0.01). In erythrocytes, the antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase did not differ postnatally. Indicators of oxidative damage in plasma (sulfhydryl/protein ratio and thiobarbituric acid reactive substances) showed the same postnatal course in both groups and were not influenced by oxygen therapy. In erythrocytes the reduced/oxidized glutathione ratio showed no consistent differences. In conclusion, this study, using erythrocytes and plasma, does not provide convincing evidence of oxidative damage and diminished antioxidant defenses in preterm infants with neonatal respiratory distress syndrome. 相似文献
73.
妊娠末期催产素刺激子宫蜕膜细胞产生与分娩有关的前列腺素,但其作用方式仍未知。本实验分离妊娠19d大鼠蜕膜细胞,测定了催产素作用后蜕膜细胞内游离钙的变化,结果加入0.001~1μmol·L-1催产素后,蜕膜细胞内[Ca2+]i出现瞬息增加,其峰值与催产素浓度呈剂量依赖关系,且此作用有自身钝化现象。说明催产素可能激活妊娠末期大鼠蜕膜细胞内的肌醇磷酯蛋白激酶C系统。给妊娠末期大鼠ip硫酸去氢表雄酮钠盐后分离的蜕膜细胞,催产素作用引起[Ca2+]i瞬息增加峰值较对照升高。 相似文献
74.
75.
Cloning, functional activities and in vivo tissue distribution of rat NKR-P1+ TCR alpha beta + cells
Knudsen E; Seierstad T; Vaage JT; Naper C; Benestad HB; Rolstad B; Maghazachi AA 《International immunology》1997,9(7):1043-1051
We have successfully cloned nine NKR-P1+ TCR alpha beta + cells from PVG
rat spleens, utilizing murine macrophage inflammatory protein-1 alpha
(MIP-1 alpha) and IL-2. These clones are either double negative (DN,
CD4-CD8-), which included clones 3.31, 3.71, 4.19, 4.59 and 4.65, or single
positive (SP, CD4+CD8-), which included clones 1.64, 3.8, 3.76 and 3.78. No
CD8+ clone was recovered. All nine clones are restricted in terms of their
expression of the V beta antigens, since they express V beta 8.2 but not V
beta 8.5, V beta 10 or V beta 16. These clones are agranular and they fall
to generate NK or LAK activity upon incubation with IL-2, IL-12 or their
combination. On the basis of their production of intracellular cytokines
they can be divided into three categories: (I) SP clones (1.64, 3.8, 3.76
and 3.78) do not produce IL-2 or IL-4, but produce IFN-gamma and IL-12, and
they vary in their production of IL-1, RANTES or tumor necrosis factor
(TNF)-alpha; (II) DN clones 4.59 and 4.65 produce IL-1 alpha and IFN-gamma
only, and fall to produce other cytokines; and (III) DN clones 3.31, 3.71
and 4.19 produce IL-1 alpha, IL-1 beta, IL-2, IL-12, IFN-gamma, RANTES and
TNF-alpha. From all the clones examined only DN clones 3.31 and to a lesser
degree 4.19 produce IL-4. In vivo tissue localization of clones 3.8, 3.31
and 4.59 shows that these cells distribute into the liver and bone marrow
24 h post i.v. administration. Their accumulation in the liver and bone
marrow along with their ability to secrete various cytokines suggest that
these cells may influence the generation, differentiation or apoptosis of
immune or hematopoietic cells.
相似文献
76.
This article reviews and analyzes studies on the utilization of care and patterns of care in psychiatric care organizations with a defined catchment area responsibility. Eight studies fulfilled the inclusion criteria. The main results of the studies were reviewed with regard to distribution of utilization, typical patterns of care, sociodemographic characteristics, clinical characteristics and, when appropriate, organizational characteristics related to utilization. The results show that a small proportion of patients use a large proportion of resources. Sociodemographic factors such as living alone or having no occupation in some of the studies predicted a higher utilization. Only one study reported sex differences, men being more common among heavy users. In most of the studies a psychosis diagnosis predicted a higher utilization. A history of prior contacts with psychiatric care predicted a higher utilization in 2 studies. It is concluded that future studies should make efforts to develop standardized models of classification of patterns of care to enhance possibilities of comparisons. Cost, as a common unit for summarizing and comparing resource utilization, has not been used, but is viewed as a highly relevant measure. Furthermore, measures of utilization should be separated from evaluations of outcome or quality of care. However, the latter is a neglected area that should also be promoted in studies of utilization of psychiatric care to create knowledge of the relationship of utilization to outcome. 相似文献
77.
Use of peripheral blood instead of bone marrow to monitor residual disease in children with acute lymphoblastic leukemia 总被引:2,自引:2,他引:2 下载免费PDF全文
Coustan-Smith E Sancho J Hancock ML Razzouk BI Ribeiro RC Rivera GK Rubnitz JE Sandlund JT Pui CH Campana D 《Blood》2002,100(7):2399-2402
In children with acute lymphoblastic leukemia (ALL), response to treatment is assessed by bone marrow aspiration. We investigated whether minimal residual disease (MRD) can be effectively monitored in peripheral blood. We used flow cytometric techniques capable of detecting 1 leukemic cell among 10 000 or more normal cells to compare MRD measurements in 718 pairs of bone marrow and peripheral blood samples collected from 226 children during treatment for newly diagnosed ALL. MRD was detected in marrow and blood in 72 pairs and in marrow but not in blood in 67 pairs; it was undetectable in the remaining 579 pairs. Remarkably, findings in marrow and blood were completely concordant in the 150 paired samples from patients with T-lineage ALL: for each of the 35 positive marrow samples, the corresponding blood sample was positive. In B-lineage ALL, however, only 37 of 104 positive marrow samples had a corresponding positive blood sample. Notably, peripheral blood MRD in these patients was associated with a very high risk for disease recurrence. The 4-year cumulative incidence of relapse in patients with B-lineage ALL was 80.0% +/- 24.9% for those who had peripheral blood MRD at the end of remission induction therapy but only 13.3% +/- 9.1% for those with MRD confined to the marrow (P =.007). These results indicate that peripheral blood may be used to monitor MRD in patients with T-lineage ALL and that peripheral blood MRD may provide strong prognostic information in patients with B-lineage ALL. 相似文献
78.
Uncommon non‐Hodgkin lymphomas of childhood: pathological diagnosis,clinical features and treatment approaches 下载免费PDF全文
We provide a review of the pathological and clinical features for uncommon B‐cell and T‐cell lymphomas of childhood with a specific focus on advances in treatment approaches and outcomes. There is clearly a need for prospective investigation of both the clinical and biological features of the uncommon non‐Hodgkin lymphoma subtypes in childhood. These results should lead to more uniform and more effective treatment approaches. 相似文献
79.
Epstein–Barr virus (EBV) is a ubiquitous gamma‐herpesvirus that establishes a lifelong persistent infection in the oral cavity and is intermittently shed in the saliva. EBV exhibits a biphasic life cycle, supported by its dual tropism for B lymphocytes and epithelial cells, which allows the virus to be transmitted within oral lymphoid tissues. While infection is often benign, EBV is associated with a number of lymphomas and carcinomas that arise in the oral cavity and at other anatomical sites. Incomplete association of EBV in cancer has questioned if EBV is merely a passenger or a driver of the tumorigenic process. However, the ability of EBV to immortalize B cells and its prevalence in a subset of cancers has implicated EBV as a carcinogenic cofactor in cellular contexts where the viral life cycle is altered. In many cases, EBV likely acts as an agent of tumor progression rather than tumor initiation, conferring malignant phenotypes observed in EBV‐positive cancers. Given that the oral cavity serves as the main site of EBV residence and transmission, here we review the prevalence of EBV in oral malignancies and the mechanisms by which EBV acts as an agent of tumor progression. 相似文献
80.
Neutrophils are known to contain a major 67-kD protein that undergoes enhanced phosphorylation and translocation to the membrane during cell stimulation. Recent studies have assumed that this 67-kD phosphoprotein is the 67-kD subunit of the phagocyte oxidase (p67-phox). We compare here the protein phosphorylation patterns in lysates of normal neutrophils and neutrophils from patients with chronic granulomatous disease (CGD) that are completely deficient in p67-phox. The phosphoproteins were labeled by incubation of the cells with radioactive inorganic phosphate (32Pi) or by the addition of [gamma- 32P]ATP to electropermeabilized neutrophils. With either method, stimulation of the normal or CGD cells always resulted in an enhanced incorporation of 32p into two proteins in the 67-kD area. The extent of phosphorylation of these two proteins was very similar in the normal and CGD cells when permeabilized neutrophils loaded with [gamma - 32P]ATP were compared. Moreover, no overall differences in the protein phosphorylation patterns were observed between the normal and CGD cells. Our data indicate that the major 67-kD phosphoproteins observed in stimulated neutrophils are clearly different from p67-phox. 相似文献