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51.
A Y842D mutation within the activation loop of fms-like tyrosine kinase 3 (FLT3) has been shown to confer strong resistance to sorafenib in vitro. Whether this type of mutation exerts clinically significant effects in patients with acute myeloid leukaemia (AML) remains unclear. Here, a novel Y842D activating mutation within the kinase domain of FLT3, in a pregnant patient with de novo hyperleucocyte acute myeloid leukaemia, is described. Following induction failure with standard dose idarubicin and cytarabine (IA), the patient received re-induction combined with midostaurin, a promising agent targeting mutant-FLT3, and IA regimen. Fortunately, morphological remission was achieved. During the period of midostaurin treatment, the patient exhibited a symptom that was characteristic of differentiation syndrome, which disappeared following treatment with methylprednisolone. The present case revealed that Y842D, an uncommon activating mutation in the activation loop of FLT3, may be a midostaurin-sensitive mutation type in patients with acute myeloid leukaemia.  相似文献   
52.
The timely and accurate diagnosis of porcine epidemic diarrhea virus (PEDV) infection is crucial to reduce the risk of viral transmission. Therefore, the objective of this review was to evaluate the overall diagnostic accuracy of rapid point-of-care tests (POCTs) for PEDV. Studies published before 7 January 2022 were identified by searching PubMed, EMBASE, Springer Link, and Web of Science databases, using subject headings or keywords related to point of care and rapid test diagnostic for PEDV and PED. Two investigators independently extracted data, rated risk of bias, and assessed the quality using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The bivariate model and the hierarchical summary receiver operating characteristic (HSROC) model were used for performing the meta-analysis. Threshold effect, subgroup analysis, and meta-regression were applied to explore heterogeneity. Of the 2908 records identified, 24 eligible studies involving 3264 specimens were enrolled in the meta-analysis, including 11 studies on evaluation of lateral flow immunochromatography assay (ICA)-based, and 13 on nucleic acid isothermal amplification (NAIA)-based POCTs. The overall pooled sensitivity, specificity and diagnostic odds ratio (DOR) were 0.95 (95% CI: 0.92–0.97), 0.96 (95% CI 0.88–0.99) and 480 (95% CI 111–2074), respectively; for ICA-based POCTs and the corresponding values for NAIA-based, POCTs were 0.97 (95% CI 0.94–0.99), 0.98 (95% CI 0.91–0.99) and 1517 (95% CI 290–7943), respectively. The two tests showed highly comparable and satisfactory diagnostic performance in clinical utility. These results support current recommendations for the use of rapid POC tests when PEDV is suspected.  相似文献   
53.
The depressant effects of phencyclidine [1-(1-phenylcyclohexyl) piperidine, PCP] and three of its analogs (m-amino-PCP, m-nitro-PCP, and PCP-methyliodide) on the spontaneous action potential discharge of cerebellar Purkinje neurons in urethane-anesthetized rats were examined in this study. Both intraperitoneal injection and micro-pressure ejection were employed as routes of drug administration. The relative potency after parenteral administration corresponded closely with previous findings in behavioral test paradigms. PCP and m-amino-PCP were equipotent, m-nitro PCP was less potent than either PCP or m-amino-PCP, and PCP-methyliodide showed almost no activity. After local administration onto neurons, m-amino-PCP was significantly more potent than PCP, while PCP, m-nitro-PCP, and PCP-methyliodide were equipotent. Tritiated PCP, m-nitro PCP, and m-amino PCP have similar distribution and metabolism in cerebellum. PCP-methyliodide, a quaternary ion, does not cross the blood brain barrier. M-nitro PCP is appreciably less ionized at pH 7.4 than PCP or m-amino-PCP and, therefore, may be more easily sequestered into lipids. Differences between PCP and its analogs found in experiments which employ parenteral administration may reflect differences in drug distribution. These differences are minimized when these drugs are administered directly onto neurons via pressure microejection.  相似文献   
54.
目的 研究中国人2型糖尿病合并高甘油三酯血症患者脂蛋白醒酶(1ipoprotein lipase,LPL)基因突变及对酶功能的影响,从脂代谢途径探讨引发糖尿病的遗传因素。方法 对高甘油三酯及血脂正常的2型糖尿病患者和正常人的LPL基因进行研究。利用PCR—SSCP、PCR—RFLP及DNA测序技术对LPL基因的启动子和10个外显子区域进行突变检测,针对特异位点进行体外定点突变和酶活力表达研究,利用网上工具平台Swiss-PDB Viewer对正常和突变蛋白进行二级结构模拟分析。结果 在177例高甘油三酯2型糖尿病患者中检测到4种错义突变:Ala71Thr、Val181IIe、Glyl88Glu和Glu242Lys,在正常血脂的糖尿病患者和健康人组中没有检出以上突变。这4种突变位于进化上高度保守的氨基酸位点,并分别在高度保守的外显子3、5及6区域。体内和体外酶活力研究表明,这4个突变均引起了酶活力降低甚至失活,其改变程度可以从它们所在序列的保守性、在酶功能结构城中的相对位置、相应的二级结构改变和氨基酸特性获得解释。结论 在受累个体中,LPL突变是引起患者血浆甘油三酯升高的直接原因,是其发展成2型糖尿病的遗传性易感因素。  相似文献   
55.
Ideal halogen-free instinct flame-retardant waterborne polyurethanes have high flame-retardant efficiency, environmental friendliness, fine compatibility, and good thermostability. Phosphorus flame-retardants are currently widely used in halogen-free instinct flame-retardant waterborne polyurethanes (HIFWPU), especially those with phosphorous–nitrogen co-structures. Phosphorous–nitrogen HIFWPU have become a hotspot because their co-structures provide higher flame-retardance as compared to waterborne polyurethanes. This review introduces three main types of HIFWPU based on composition, performance and application. HIFWPU not only have improved flame-retardance but also satisfy the various requirements for functionality. HIFWPU have been widely developed in textile, furniture, automobile, and aerospace applications.

Ideal halogen-free instinct flame-retardant waterborne polyurethanes have high flame-retardant efficiency, environmental friendliness, fine compatibility, and good thermostability.  相似文献   
56.
We present a case of histologically confirmed lipomatous meningioma, the first to our knowledge reported in Hong Kong. A 75‐year‐old woman presented to us with on and off dizziness for 1 month. Computed tomography (CT) of the brain showed an extra‐axial mass lesion containing fat and solid enhancing foci at her right frontal region. The definitive diagnosis could be made preoperatively. Postoperative histological examination of the tumour revealed the diagnosis of lipomatous meningioma. We have reviewed the literature and discussed the diagnostic clues, clinical presentation and pathology of this rare tumour.  相似文献   
57.
58.
背景:抗病毒药物能减少早期的巨细胞病毒疾病,但有较强的毒性和引起晚期巨细胞病毒疾病发生的可能。为了更好地防治巨细胞病毒疾病,研究细胞毒性T淋巴细胞控制巨细胞病毒再活化的作用是很关键的,荧光HLA-肽四聚体是一个很好的工具,被用来监测移植受者的巨细胞病毒特异细胞毒性T淋巴细胞的恢复。 目的:探讨HLA-肽四聚体和过继性免疫疗法在治疗巨细胞病毒疾病中的作用。 方法:由第一、二作者检索2003/2009 PubMed数据库及万方数据库有关移植后巨细胞病毒特异细胞毒性T淋巴细胞检测、抗病毒药物应用、HLA肽四聚体应用、过继性免疫治疗作用的文献,英文检索词为“HLA-peptide tetramers, cytomegalovirus, specific CTL, adoptive immunotherapy”,中文检索词为“HLA-肽四聚体,巨细胞病毒,特异细胞毒性T淋巴细胞,过继性免疫治疗”。排除重复性研究,纳入29篇归纳总结。 结果与结论:用巨细胞病毒特异细胞毒性T淋巴细胞进行的过继性免疫治疗是非常完美的策略,然而,产生这些细胞是昂贵和耗时的,因此治疗不是在每个移植中心都能进行。用HLA-肽四聚体从巨细胞病毒血清阳性供者外周血中选择巨细胞病毒特异细胞毒性T淋巴细胞是非常有希望的策略,使过继性免疫疗法更容易进行。 关键词:HLA-肽四聚体;过继性免疫治疗;巨细胞病毒疾病;特异T细胞;细胞毒性T淋巴细胞  相似文献   
59.
In this report, we describe a Taiwanese (Han Chinese) family with Leber's hereditary optic neuropathy. The family carried a mitochondrial DNA mutation (mtDNA m.14484T>C) associated with spontaneous visual improvement. A 15-year-old boy from this family was diagnosed with Leber's hereditary optic neuropathy 6 months after losing his vision. His vision recovered after 8 months of supportive treatment. His mother, older brother, and two sisters also had the same mutation and had previously experienced vision loss. In this family, there was no male predominance.  相似文献   
60.
This study critically examines the concepts of dignity and liminality at the end-of-life, in an effort to better understand the processes of healing within suffering among Chinese terminal cancer patients receiving palliative care services in Hong Kong. Meaning-oriented interviews were conducted with 18 Chinese terminal patients, aged 44 to 98, to elicit the narratives and stories of their illness experience. All interviews were analyzed using grounded theory and supplemented by ethnographic observations and field notes. Two major themes and eight subprocesses of healing adopted by patients to achieve and maintain dignity were identified: (a) personal autonomy, which encompasses the need to (i) regain control over living environments, (ii) maintain self-sufficiency despite institutional care, (ii) make informed care decisions to reduce sense of burden, and (iv) engage in future planning to create a lasting legacy; and (b) family connectedness, which encompasses the need to (i) maintain close ties with family members to express appreciation, (ii) achieve reconciliation, (iii) fulfill family obligations, and (iv) establish a continuing bond that transcends generations. Implications of these themes for advanced care planning and life review interventions were discussed with the goal of enhancing patient autonomy and family connectedness, and thereby providing structure and meaning for Chinese terminal patients and their families at the end of life.  相似文献   
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