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31.
植入前诊断是产前诊断非常早的一种方法,目的是放弃携带严重遗传病的胚胎,将健康胚胎植入母体。两种主要的方法是聚合酶链反应(PCR)和荧光原位杂交(FISH)。PCR用于单基因病诊断,FISH用于染色体异常诊断。临床主要应用于存在遗传风险的患者如携带单基因病和染色体易位的患者。随着分子生物学技术的飞速发展,如比较基因组(CGH),全基因组扩增技术(WGA),引物延伸预扩增(PEP),间期核转换技术及DNA芯片技术(DNAchip)等PGD先进检测手段的应用,单细胞用于诊断单基因或多基因突变及染色体疾病,为期不远。 相似文献
32.
目的:检测急性白血病(acute leukemia,AL)病人谷胱甘肽硫转移酶-π(glutathione—S—transferltse-π,GST-π)、多药耐药相关蛋白1(multi—drug resistance relevant protein 1,MRP1)的表达,探讨二者与AL多药耐药(multi—drug resistance,MDR)的关系及临床意义,明确二者在AL中的表达有无相关性以及两者表达与AL病人临床特征的关系。方法:采用免疫组织化学S—P法检测80例AL病人及30例正常人外周血单个核细胞GST-π、MPP1表达。运用SPSS10.0统计软件,采用X^2检验、四格表精确概率法、t检验、直线相关分析方法统计结果。结果:GST-π、MRP1在难治组的阳性率均高于初治组和完全缓解组;在初治组的阳性率均高于对照组。GST-π、MRP1在AL难治组中的表达具有高度相关性。GST-π、MRP1表达阳性组完全缓解率低于阴性组。GST-π、MRP1的表达与AL难治组病人年龄、性别、骨髓幼稚细胞比例及外周血白细胞计数无关。且两者在急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)组、急性非淋巴细胞白血病(acute nonlymphoblastic leukemia,ANLL)组表达无差别。结论:GST-π和MRP1的高表达与AL临床耐药有关;GST-π和MRP1在难治组中的表达密切相关;GST-π和MRP1表达阳性的AL病人的完全缓解率明显降低,两者可能是影响AL疗效的重要指标;GST-π和MRP1在难治组表达阳性率与年龄、性别、外周血白细胞计数、骨髓幼稚细胞比例可能无关,且在ALL组与ANLL组中差别无统计学意义。 相似文献
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目的:了解基质金属蛋白酶-2(MMP-2)及转化生长因子-β1(TGF-β1)在心肌梗死大鼠左室重构及心衰发展过程中的改变,以及氟伐他汀的干预作用,探讨心梗后心衰的发生机制。方法:选用雄性SD大鼠67只随机分为假手术组、心梗组和心梗他汀组,经冠状动脉前降支结扎术建立心肌梗死后心衰模型,手术24 h后心梗他汀组大鼠管饲氟伐他汀4 mg·kg-1·d-1,假手术组和心梗组大鼠管饲安慰剂。术后3 d、4周、8周检测大鼠非梗死区心肌MMP-2的含量(Western-blot法)、胶原、TGF-β1的改变(免疫组化法),压力传感器记录左室血流动力学改变。结果:术后各时点非梗死区心肌的MMP-2含量,心梗组及心梗他汀组显著高于假手术组(P<0.05),而心梗他汀组显著低于心梗组(P<0.05);术后各组各时点非梗死区心肌TGF-β1表达的变化趋势与MMP-2相同;与心梗组比较,心梗他汀组术后4周和8周的心功能明显改善,胶原容积分数(CVF)及Ⅰ/Ⅲ型胶原比值(Ratio of type Ⅰ/Ⅲ)降低(P<0.05)。结论:氟伐他汀通过减少非梗死区心肌MMP-2和TGF-β1的含量,而减轻心梗后非梗死区心肌胶原网络的破坏及反应性胶原的过度沉积,从而预防和逆转心室重构,改善心脏功能。 相似文献
35.
Bariatric surgery is associated with increased risk of new‐onset inflammatory bowel disease: case series and national database study
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36.
Felicity Fanning Sharon Foley Elizabeth Lawlor Stephen McWilliams Deirdre Jackson Laoise Renwick Marie Sutton Niall Turner Anthony Kinsella Timothy Trimble Eadbhard O'Callaghan 《Early intervention in psychiatry》2012,6(4):432-441
Aim: Most national guidelines recommend psychological therapy for people with first‐episode psychosis (FEP) but interventions proven effective in randomized control trials (RCTs) conducted in research settings do not always translate effectively to real‐world clinical environments. In a limited health system, it is important to understand the system and patient barriers to participation in effective treatment. We sought to determine what patient characteristics influenced clinicians' decision to refer or not to refer to group cognitive behavioural therapy for FEP and what characteristics were associated with those referred attending/not attending and adhering/not adhering to the programme. Methods: Between 2006 and 2008, all cases of confirmed FEP from a defined geographical region were examined using the Structured Clinical Interview for DSM‐IV‐TR Axis I Disorders for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM‐IV) diagnoses, the Scale for Assessment of Positive Symptoms, Scale for Assessment of Negative Symptoms, Calgary Depression Scale for Schizophrenia and Birchwood Insight Scale. Duration of untreated psychosis was established using the Beiser Scale. Results: Of the 124 (77 males, 47 females) people in the final sample, 88 (72%) were referred for cognitive behavioural therapy (CBT), 52 (59%) attended and 12 (23%) did not complete CBT. Those with higher levels of insight into the need for treatment (U = 740.00, z = −2.63, P = 0.008) and higher levels of positive symptoms (t (120) = −3.064, P = 0.003) were more likely to be referred to CBT. Those with higher educational attainment (χ2 = 9.48, P = 0.03) and fewer negative symptoms, particularly in relation to global attention (t (85) = 2.32, P = 0.03), were more likely to attend and complete CBT. Conclusion: Within an early intervention service for FEP, it appears that individuals with less education, more negative symptoms and less insight experienced significant barriers to successfully completing group CBT. More information for referring clinicians about the benefits of CBT for FEP could help increase referral rates. Assertive outreach for people at risk of disengaging or non‐adherence should also be considered. 相似文献
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Erythropoietic activity is known to be closely associated with marrow iron uptake. A modification of the standard measure of plasma iron turnover has been developed in which erythron transferrin uptake (ETU) rather than iron uptake has been calculated. The ETU has the advantage of providing a parameter of erythroid marrow activity independent of change produced by plasma iron and transferrin saturation. Measurements in 80 patients with anemia were compared to the normal value of 60 +/- 12 mumol/L whole blood/d. The mean ETU for ten patients with severe aplastic anemia and for six patients with pure red-cell aplasia were 12 +/- 8 and 12 +/- 11 mumol/L whole blood/d, respectively. In ten transfusion-dependent patients with renal failure under dialysis therapy, the mean value was 35 +/- 11, while ten other dialyzed patients who were transfusion independent had a mean ETU of 73 +/- 21 mumol/L whole blood/d. Sixteen patients with hemolytic anemia had an average ETU of 400 +/- 130, while 28 patients with ineffective erythropoiesis had a mean value of 474 +/- 147 mumol/L whole blood/d. While patients with hypoproliferative anemia showed no relation between the severity of anemia and ETU, those with hyperproliferative erythroid marrow showed increasing values as the anemia became more severe. Sequential measurements in patients with aplastic anemia under treatment and in thalassemic patients under transfusion therapy showed the value of this measurement in monitoring the effects of treatment on erythroid marrow activity. It is concluded that the measurement of ETU provides a more direct ferrokinetic evaluation of erythroid activity in anemic states. 相似文献
40.
Identification of T lymphocytes in human mixed hemopoietic colonies 总被引:11,自引:0,他引:11
The addition of a T-cell growth-promoting medium (PHA-TCM) to culture conditions that support growth of multi-lineage hemopoietic colonies enhances the proliferation of cells with lymphoid morphology within these colonies. These cells were identified as T lymphocytes by their ability to form rosettes with SRBC and their reaction with monoclonal antibodies (OKT3, OKT4) directed against T-cell-specific surface components. They continue to proliferate extensively under the influence of PHA-TCM after transfer of mixed colonies into liquid suspension culture. Supportive evidence for a common progenitor of myeloid and lymphoid cells within single mixed colonies is provided by Y-chromatin body analysis of E-rosette positive and negative cells in colonies grown in cocultures of male and female bone marrow cells. 相似文献