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31.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease. 相似文献
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OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation. 相似文献
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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
36.
目的 白细胞介素 1 3(IL 1 3)是新近发现的一种抗炎性细胞因子 ,其在肾小球肾炎中的作用尚不清楚 ,该研究探讨脂多糖 (LPS)对体外培养的人肾小球系膜细胞 (HMC)表达IL 1 3作用以及IL 1 3对HMC促炎性细胞因子、趋化因子和促纤维化因子基因表达的影响。方法 体外培养HMC ,加入不同浓度的LPS和 (或 )IL 1 3后 ,用逆转录 -聚合酶链反应和ELISA检测HMCIL 1 3mRNA表达和细胞培养上清液中IL 1 3蛋白含量 ;应用核酸酶保护法检测HMC肿瘤坏死因子 α(TNF α)、白介素 - 1α(IL 1α)、白介素 - 1 β(IL 1 β)、单核细胞趋化蛋白 1(MCP 1 )、白介素 8(IL 8)、转化生长因子 - β1 (TGF β1 )mRNA的表达。 结果 未予LPS刺激的HMC不表达IL 1 3mRNA和蛋白 ;LPS呈剂量依赖性和时间依赖性诱导HMC表达IL 1 3mRNA和分泌IL 1 3蛋白。HMC受LPS刺激后 1 2h即可表达IL 1 3mRNA ,4 8h达高峰 ,72h仍维持在较高的水平。HMC受LPS刺激后 2 4h ,其培养上清液中检测到IL 1 3蛋白 ,4 8h和 72h进一步增加。外源性IL 1 3呈剂量依赖性地抑制LPS诱导的系膜细胞TNF α ,IL 1α ,IL 1 β ,MCP 1 ,IL 8,TGF β1mRNA的表达。应用抗IL 1 3抗体中和内源性IL 1 3后 ,上述炎症因子表达增强。结论 IL 1 3是HMC自分泌因子。IL 1 3可抑制LPS诱导 相似文献
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Lorna M Gibson Martha F Hanby Sarah M Al-Bachari Laura M Parkes Stuart M Allan Hedley CA Emsley 《Journal of cerebral blood flow and metabolism》2014,34(4):564-570
The interface between cerebrovascular disease (CVD) and epilepsy is complex and multifaceted. Late-onset epilepsy (LOE) is increasingly common and is often attributed to CVD, and is indeed associated with an increased risk of stroke. This relationship is easily recognizable where there is a history of stroke, particularly involving the cerebral cortex. However, the relationship with otherwise occult, subcortical CVD is currently less well established yet causality is often invoked. In this review, we consider the diagnosis of LOE in clinical practice—including its behaviour as a potential mimic of acute ischemic stroke and transient ischemic attack; evidence for an association between occult CVD and LOE; and potential mechanisms of epileptogenesis in occult CVD, including potential interrelationships between disordered cerebral metabolism and perfusion, disrupted neurovascular unit integrity, blood–brain barrier dysfunction, and inflammation. We also discuss recently recognized issues concerning antiepileptic drug treatment and vascular risk and consider a variety of less common CVD entities associated with seizures. 相似文献
39.
Escarlata Angullo-Martínez Enrique Carretero-Anibarro Ignacio Manuel Snchez Barrancos Xavier Cos Claramunt Domingo Orozco Beltrn Jos Luis Torres Baile Patxi Ezkurra Loiola en representacin del Grupo de Trabajo de Diabetes de la SemFyC en representacin del Grupo de Trabajo de Diabetes de la SemFyC 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2021,53(4)
Las circunstancias actuales provocadas por la COVID-19 nos obligan a los profesionales de atención primaria a idear nuevas formas de garantizar la atención sanitaria de nuestros pacientes con diabetes tipo 2 (DM2). Existen evidencias que respaldan la eficacia de la telemedicina en el control glucémico de los pacientes con DM2. Ante la rápida adaptación de la práctica clínica al uso de la telemedicina, el Grupo de Trabajo de Diabetes de la Sociedad Española de Medicina Familiar y Comunitaria (SemFyC) optó por elaborar un documento de consenso plasmado en un algoritmo de actuación/seguimiento telemático en la atención de los pacientes con DM2.Palabras clave: Telemedicina, Diabetes mellitus tipo 2, COVID-19 相似文献
40.
Biologic basis for interleukin-1 in disease 总被引:164,自引:6,他引:164
To understand the role of the proinflammatory cytokine interleukin-1 (IL-1) in disease, investigators have studied how production of the different members of the IL-1 family is controlled, the various biologic activities of IL-1, the distinct and various functions of the IL-1 receptor (IL-1R) family, and the complexity of intracellular signaling. Mice deficient in IL-1Beta, IL-1Beta converting enzyme, and IL-1R type I have also been studied. Humans have been injected with IL- 1 (either IL-1alpha or IL-1beta) for enhancing bone marrow recovery and for cancer treatment. The IL-1-specific receptor antagonist (IL-1Ra) has also been tested in clinical trials. The topics discussed in this review include production and activities of IL-1 and IL-1Ra molecules, the effects of IL-1 on gene expression, functions of cell-bound and soluble IL-1 receptors, the importance of the IL-1R accessory protein, newly discovered signal transduction pathways, naturally occurring cytokines limiting IL-1 production or activity, the effects of blocking cyclooxygenase and nitric oxide, and the outcomes of IL-1 and IL-1 Ra in human trials. Special attention is paid to IL-1beta converting enzyme and programmed cell death. The roles of IL-1 in hematopoiesis, leukemia, atherosclerosis, and growth of solid tumors are also discussed. This is a lengthy review, with 586 citations chosen to illustrate specific areas of interest rather than a compendium of references. At the end of each section, a short commentary summarizes what the author considers established or controversial topics linking the biology of IL-1 to mechanisms of disease. 相似文献