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61.
Preliminary data indicate that the concentration of circulating cortisol may affect the binding of testosterone to plasma proteins. This interdependency was evaluated by the assessment of plasma cortisol, salivary (ST) and plasma total testosterone (TT), testosterone not bound to sex-hormone-binding globulin (n-SHBGT), and free testosterone (FT) in normal and in hyperandrogenemic women during combined dexamethasone/synthetic corticotropin administration. The concentrations of TT, FT, and ST significantly increased (P less than 0.001) during this dynamic test both in the controls and in hirsute women. Remarkably, however, n-SHBGT remained virtually unchanged in normal women in the follicular phase, decreasing in the luteal phase, and decreasing even more markedly in the hirsute women. Both the normal and the hirsute women showed a statistically significant negative correlation between the percentage of n-SHBGT and plasma total cortisol (P less than 0.001). The apparent decrease of n-SHBGT was the result of displacement of T from corticosteroid-binding globulin (CBG) by the increase in cortisol after the infusion of synthetic corticotropin: the CBG-bound T was measured as n-SHBGT because CBG was not precipitated with 50% saturated ammonium sulfate. Our results indicate that ST or FT better represents the clinical status of androgenicity than does n-SHBGT, as assessed by ammonium sulfate precipitation, because n-SHBGT also depends on the concentration of cortisol. 相似文献
62.
The authors studied the natural history of human immunodeficiency virus (HIV) exposure in 187 hemophiliacs followed for an average of 45 months. Overall, 55 percent developed antibody specific for HIV and 21 percent developed persistent generalized lymphadenopathy. Most patients seroconverted sometime between early 1982 and the end of 1984. Four patients developed acquired immune deficiency syndrome (AIDS) and four seropositive patients developed idiopathic thrombocytopenia (ITP). One of the four patients who developed AIDS and three of the four with ITP had preexisting lymphadenopathy. None of the 10 patients with lymphadenopathy or the 20 asymptomatic patients was seropositive for human T-lymphotropic virus, type I. Although seropositivity and lymphadenopathy have been found in many of the authors' patients, few have developed clinical disease that can be related to HIV infection. 相似文献
63.
Growth differentiation factor 15 in patients with congenital dyserythropoietic anaemia (CDA) type II
Casanovas G Swinkels DW Altamura S Schwarz K Laarakkers CM Gross HJ Wiesneth M Heimpel H Muckenthaler MU 《Journal of molecular medicine (Berlin, Germany)》2011,89(8):811-816
Congenital dyserythropoietic anaemias (CDAs) are heterogeneous, hereditary disorders hallmarked by ineffective erythropoiesis
and tissue iron overload. Growth differentiation factor 15 (GDF15) was suggested to mediate iron overload in iron-loading
anaemias, such as the thalassaemias and CDAI by suppressing hepcidin, the key regulator of iron absorption. Here, we show
that serum GDF15 concentrations are elevated in subjects with CDAI and CDAII. Despite similar disease characteristics, CDAI
patients present with significantly higher GDF15 concentrations compared to CDAII patients. Hepcidin concentrations are inappropriately
low in CDAII patients considering the severe hepatic iron overload associated with this disorder. GDF15 significantly correlates
with the degree of anaemia (Hb), the response of erythropoiesis (reticulocyte index) as well as with iron availability in
the serum (transferrin saturation). The observation that GDF15 is elevated in CDAII patients is consistent with the proposal
that GDF15 is among the erythroid factors down-regulating hepcidin and contributing to iron overload in conditions of dyserythropoiesis. 相似文献
64.
目的:探讨结节性硬化症(TSC)的CT表现和鉴别诊断。方法:分析7例诊断为结节性硬化症的CT资料。重点观察病变部位、大小、钙化程度及其他改变。结果:7例均有室管膜下结节,共计77个,其中钙化结节39个.80%结节位于侧脑室体部室管膜下;5例皮质及皮质下多发结节均无钙化,额枕叶为著,其次为颞顶叶:4例皮质下白质有不同程度低密度改变,主要围绕侧脑室体部及额角周围。4例合并其他畸形。结论:室管膜下多发结节并钙化,皮质异常脑回及不规则形低密度影、脑白质放射状分布的低密度改变是CT诊断结节性硬化症的主要征象,其中室管膜下结节并钙化是较有特征性的表现。CT结合临床可做出明确诊断并发现其他畸形。 相似文献
65.
目的:了解乌审旗妇女宫颈癌及癌前病变的发病现状,探讨子宫颈液基细胞学(Thinprep paptest,TCT)结合阴道镜检查的诊断价值。方法:对3 000名乌审旗妇女进行TCT筛查,对TCT阳性(细胞学TBS分类为不典型鳞状细胞以上)的妇女进行阴道镜及镜下多点活组织检查(活检),分析TCT阳性者的阴道镜检查及活检结果,比较TCT阳性者中不同年龄段患者的活检结果。结果:3 000名受检者中,TCT阳性537例(17.9%),其中经活检证实为宫颈上皮内瘤变(cervical intraepthelial neoplasia,CIN)190例(6.3%),宫颈浸润癌2例(0.07%),537例TCT阳性者中,阴道镜检查正常264例(49.2%),其中活检结果为CIN34例,阴道镜的假阴性率为12.9%,异常273例(50.8%),其中活检结果为湿疣34例,CIN或浸润癌158例,阴道镜与活检的诊断符合率达70.3%(192/273)。TCT为轻度鳞状上皮内病变、高度鳞状上皮内病变、鳞状细胞癌的病例与活检的诊断符合率分别为50.4%,88.3%和2/2,假阳性率则分别为49.6%、11%和0。537例TCT阳性者中,2030岁组、3140岁组,4147岁组的CIN检出率分别为33.7%、44.5%2、6.7%(P〈0.05)。结论:乌审旗妇女CIN的发生率高,是宫颈癌的高发人群。TCT结合阴道镜检查是较好的宫颈癌筛查手段之一。 相似文献
66.
SM Vieira HP Lemos R Grespan MH Napimoga D Dal-Secco A Freitas TM Cunha WA Verri Jr DA Souza-Junior MC Jamur KS Fernandes C Oliver JS Silva MM Teixeira FQ Cunha 《British journal of pharmacology》2009,158(3):779-789
Background and purpose:
Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.Experimental approach:
Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.Key results:
Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.Conclusion and implications:
Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1. 相似文献67.
68.
69.
Prevention and management of delayed transfer of older people from hospital to community settings is an enduring issue in industrialised societies and is the subject of many recent policies in the United Kingdom. A deeper, evidence-based understanding of the complex organizational and interprofessional issues which contribute to delays in transfer has emerged in recent years. Despite this, and the relative success of recent policies, two recent reviews of the area highlight the lack of studies on patients' perspectives. We sought to address this deficit by using conversational interviews and a phenomenological approach to explore and interpret participants' perceptions of delayed transfer from hospital into the community. A purposive sampling strategy was employed to incorporate participants from different categories of delay identified on weekly Situation Reports. Participants aged 65 years and over (mean age 82 +/- 5.4 years) and with a mean delay of 32 days (+/- 26) were recruited from three hospitals based in two NHS Trusts in the South of England. This paper focuses on their perceptions of the effects of delayed transfer into the community, their involvement in discharge planning and future community care needs. Our findings show that participants actively or passively relinquished their involvement in the processes of discharge planning because of the perceived expertise of others and also feelings of disempowerment secondary to poor health, low mood, dependency, lack of information and the intricacies of discharge planning processes for complex community care needs. Participants expressed a longing for continuity, emphasised the importance of social contact and sometimes appeared unrealistic about their future care needs. While current policies may have helped reduce overall numbers of delayed patients in the UK, our study suggests that there is scope for improvement in the involvement of delayed patients in planning their discharge into the community. 相似文献
70.