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排序方式: 共有1380条查询结果,搜索用时 15 毫秒
931.
Lymphocytopenia as an unfavorable prognostic factor in patients with cytomegalovirus infection after bone marrow transplantation 总被引:2,自引:3,他引:2
Einsele H; Ehninger G; Steidle M; Fischer I; Bihler S; Gerneth F; Vallbracht A; Schmidt H; Waller HD; Muller CA 《Blood》1993,82(5):1672-1678
Sixty-three recipients of an allogeneic marrow transplant were screened for the occurrence of cytomegalovirus (CMV) infection and clinical parameters possibly predicting the development of CMV disease in a retrospective study. Blood and urine samples obtained from these patients were screened weekly after bone marrow transplantation (BMT) for the presence of CMV by polymerase chain reaction (PCR) and virus culture technique. Forty-six of the 63 patients studied were found to be CMV-positive by PCR technique in blood and urine samples at a median of 29 days after BMT. In 33 of these 46 patients, CMV could be cultured from urine samples and 16 of the 46 had culture-positive viremia. Twenty-eight of these 46 PCR-positive patients developed CMV disease. Whereas PCR assays showed an optimal negative predictive value and sensitivity for the development of CMV disease, their positive predictive value was 61% and could not be remarkably increased when culture-proven viruria (64%) and viremia (69%) were considered. Acute graft-versus-host disease (GVHD) grade 2 to 4 (P < .05), but not underlying disease, conditioning therapy, or GVHD prophylaxis, was associated with CMV infection. On day +49, a remarkable decrease (P < .001) in the lymphocyte count, as well as in the absolute number of CD4+, CD8+, and CD56+ lymphocytes, occurred only among the patients who later developed CMV disease. The decrease of all of these cell counts, but predominantly the CD4+ T cells, to less than 100/microL on day +49 after BMT showed a very high positive predictive value (100%) for the development of CMV disease in patients with PCR-proven viremia. Persisting CD4 lymphopenia after antiviral therapy was only observed in patients who finally died of CMV disease. Thus, immunophenotyping of the patients after BMT in addition to a highly sensitive virus detection assay might help to identify patients at high risk to develop CMV disease and indicate the need for additional adoptive immunotherapy. 相似文献
932.
Long-range mapping of the Philadelphia chromosome by pulsed-field gel electrophoresis 总被引:6,自引:0,他引:6
The Philadelphia chromosome (Ph1) of chronic myelogenous leukemia (CML) contains sequences from chromosome 9, including the ABL protooncogene, that have been translocated to the breakpoint cluster region (bcr) of chromosome 22, giving rise to a bcr-ABL fusion gene, whose product has been implicated in the genesis of CML. Although chromosome 22 translocation breakpoints in CML virtually always occur within the 5.8- kilobase (kb) bcr, chromosome 9 breakpoints have been identified within the known limits of ABL in only a few instances. For a better understanding of the variability of the breakpoints on chromosome 9, we studied the CML cell line BV173. Using pulsed-field gel electrophoresis (PFGE), large-scale maps of the t(9;22) junctions were constructed. The chromosome 9 breakpoint was shown to have occurred within an ABL intron, 160 kb upstream of the v-abl homologous sequences, but still 35 kb downstream of the 5'-most ABL exon. bcr-ABL and ABL-bcr fusion genes were demonstrated on the Ph1 and the 9q+ chromosomes, respectively; both of these genes are expressed. These results suggest that the 9;22 translocation breakpoints in CML consistently occur within the limits of the large ABL gene. RNA splicing, sometimes of very large regions, appears to compensate for the variability in breakpoint location. These studies show that PFGE is a powerful new tool for the analysis of chromosomal translocations in human malignancies. 相似文献
933.
上海市长宁区160户家庭口腔健康问卷调查与分析 总被引:9,自引:0,他引:9
目的 了解上海市长宁区学生和成人的口腔保健知识知晓率、口腔卫生保健行为和求医行为。方法 对2个街道160户家庭进行口腔健康问卷入户调查。结果 学生组口腔保健知识知晓率85.94%,成人组80.23%,两组间存在显著性差异(P<0.05);学生组口腔卫生保健行为掌握率78.47%,成人组75.80%,两组间无显著性差异(P>0.05)。结论 学生和成人的口腔保健知识知晓率普遍较高,口腔卫生保健意识增强,应继续加强龋病和牙周疾病的一级和二级预防。 相似文献
934.
目的研究药学干预对老年慢性阻塞性肺疾病(COPD)患者药物服用依从性及疗效的影响。方法选取本院2013年6~12月收治的306例COPD患者,对照组和观察组在入院及出院时均给予同样的问卷调查表进行问卷调查,对照组患者由临床医师根据患者个体情况自行选择治疗方案,观察组患者由临床医师根据患者情况选择治疗方案后再由临床药师根据患者既往史、目前用药情况进行一对一的药学干预.内容包括用药指导、药物相互作用的指导、心理疏导及健康教育。结果观察组患者的总有效率98.7%,显著高于对照组的91.5%,差异有统计学意义(P〈0.05);观察组患者无药物不良反应,对照组出现9例不良反应,不良反应发生率为5.2%,两组差异有统计学意义(P〈0.05)。结论临床医师和临床药师联合干预后对老年COPD患者有较好的药物依从性和疗效,值得推广。 相似文献
935.
Recent studies have examined the synergistic effects of granulocyte- macrophage colony-stimulating factor (GM-CSF) and hematopoietin-1 (now identified as Interleukin-1, IL-1) on bone marrow colony formation. In the present report, human peripheral blood mononuclear cells (MNCs) were stimulated in vitro with recombinant human GM-CSF (rGM-CSF) and production of IL-1 alpha, IL-1 beta, and tumor necrosis factor (TNF) was measured by specific radioimmunoassays. In the MNCs of 20 individuals, rGM-CSF's ability to induce the three cytokines was variable. Nearly all donors responded to low-dose rGM-CSF (0.02 to 2 ng/mL) with production of TNF, whereas some individuals did not produce IL-1 alpha or IL-1 beta. The MNCs from some subjects stimulated with high-dose rGM-CSF (10 to 80 ng/mL) produced as much cytokine as in response to 10 ng/mL endotoxin. Localization (ie, extracellular or cell- associated cytokine) was specific for the cytokine rather than the stimulus. Indomethacin increased the amount of cytokine produced in response to rGM-CSF for IL-1 beta and TNF but not for IL-1 alpha. In addition, interferon-gamma (INF-gamma) upregulated the amount of TNF induced by rGM-CSF in all donors examined, with variable effect on IL-1 alpha and IL-1 beta. Suboptimal levels of endotoxin incubated with rGM- CSF did not alter the amount of IL-1 produced as compared with cells stimulated with rGM-CSF alone, whereas TNF production showed either no change or a slight decrease in production. These data suggest that GM- CSF may play an important role in the host defense response by stimulating production of these cytokines. 相似文献
936.
目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用. 相似文献
937.
938.
Manilal S; Sewry CA; Pereboev A; Man N; Gobbi P; Hawkes S; Love DR; Morris GE 《Human molecular genetics》1999,8(2):353-359
Emerin is a nuclear membrane protein which is missing or defective in
Emery-Dreifuss muscular dystrophy (EDMD). It is one member of a family of
lamina-associated proteins which includes LAP1, LAP2 and lamin B receptor
(LBR). A panel of 16 monoclonal antibodies (mAbs) has been mapped to six
specific sites throughout the emerin molecule using phage- displayed
peptide libraries and has been used to localize emerin in human and rabbit
heart. Several mAbs against different emerin epitopes did not recognize
intercalated discs in the heart, though they recognized cardiomyocyte
nuclei strongly, both at the rim and in intranuclear spots or channels. A
polyclonal rabbit antiserum against emerin did recognize both nuclear
membrane and intercalated discs but, after affinity purification against a
pure-emerin band on a western blot, it stained only the nuclear membrane.
These results would not be expected if immunostaining at intercalated discs
were due to a product of the emerin gene and, therefore, cast some doubt
upon the hypothesis that cardiac defects in EDMD are caused by absence of
emerin from intercalated discs. Although emerin was abundant in the
membranes of cardiomyocyte nuclei, it was absent from many non-myocyte
cells in the heart. This distribution of emerin was similar to that of
lamin A, a candidate gene for an autosomal form of EDMD. In contrast, lamin
B1 was absent from cardiomyocyte nuclei, showing that lamin B1 is not
essential for localization of emerin to the nuclear lamina. Lamin B1 is
also almost completely absent from skeletal muscle nuclei. In EDMD, the
additional absence of lamin B1 from heart and skeletal muscle nuclei which
already lack emerin may offer an alternative explanation of why these
tissues are particularly affected.
相似文献
939.
940.