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971.
972.
BACKGROUND: The pericardial bovine prosthesis Pericarbon should offer some advantages in comparison with the former generations, because its development is focused on solving previous problems and resulted in the variation of the pericardial fixation method, of valve structure and of stent coating. This hypothesis was evaluated through a retrospective follow-up. METHODS: Between 1985 and 1989, 78 Pericarbon prostheses O 29 were implanted in mitral position by the same surgeon. All patients received warfarin for the first three months to maintain an International Normalized Ratio between 2.5 and 3.5; after which they received antiaggregant therapy indefinitely. With an average follow-up period of 7.34 years for a total of 573 patient-years, we evaluated perioperative and late mortality, late morbidity (thromboembolic and haemorrhagic events, reoperations, primary tissue failures, endocarditic events) and patient clinical conditions. RESULTS: Perioperative mortality was 1.28% (1/78), late mortality was 11.6% (9/77) with 5 valve-related deaths. 5-year survival was 93% and 10-year survival 97%. Fifteen patients required reoperation for prosthetic replacement, fourteen for primary tissue failure. There were ten minor thromboembolic events, one major event, one haemorrhage and one prosthetic endocarditis (the last two with patient exitus). After 10 years (75% of patients were in New York Heart Association class I-II. CONCLUSIONS: Besides the known better haemodynamic performance, Pericarbon bioprosthesis seems to present a survival and redofreedom curve comparable to the best porcine prosthesis, with less incidence of endocarditis, thromboembolic events and prosthesis leakage.  相似文献   
973.
继双能X线吸收仪之后,定量超声测骨仪器逐渐从群体筛查发展为筛查兼诊断手段,从补充、辅助工具进化成为潜在的主力。然而,在骨质疏松和骨折问题的本质,超声测骨仪器的产品名称、检测参数、派生参数、声学特性参数与骨矿密度相关性、产品性能表征与检验等方面,国内外均存在严重误读。本文就所涉及的一系列基本概念作了系统厘清,以期推动该类产品的科学、健康发展。  相似文献   
974.
[目的] 对墨旱莲中的化学成分进行分离鉴定。[方法] 采用正相硅胶、反相ODS(十八烷基键合硅胶)、凝胶等柱色谱及制备型高效液相色谱(HPLC)法分离纯化, 并利用质谱分析(MS)、核磁共振波谱(NMR)等方法对化合物结构进行鉴定。[结果] 从墨旱莲体积分数为70%的乙醇提取物中分离鉴定了9个化合物, 分别鉴定为2,2';5', 2"-三联噻酚(1)、5-醛基-2,2';5', 2"-三联噻酚(2)、5-羟甲基-2,2';5', 2"-三联噻酚(3)、2,2';5', 2"-三联噻酚-5-羧酸(4)、5-醛基-5'-(3-丁烯-1-炔基)-2,2'-二联噻酚(5)和5-丁-1'-炔-3'-羟基-4'-氯-(2-戊-1", 3"二炔)-噻酚(6),二氢猕猴桃内酯(7),黑麦草内酯(8),原儿茶酸乙酯(9).[结论] 化合物6~9为首次从鳢肠属植物中分离得到。  相似文献   
975.
目的探讨超声造影对壶腹部良恶性病变鉴别诊断的临床价值。方法回顾性分析62例经手术病理组织检查或胆道镜检查证实的壶腹部病变患者,包括壶腹部癌16例、胆总管下段癌11例,十二指肠乳头癌6例,胰头癌5例,胆总管下段结石或胆泥21例,十二指肠乳头炎3例。比较常规超声与超声造影对壶腹部病变的显示能力及良恶性病变的诊断正确性,并分析其超声造影表现。结果超声造影对病变显示率98.4%(61/62)明显优于常规超声54.8%(34/62),其差异有统计学意义(P<0.001);常规超声与超声造影对壶腹部病变诊断的准确性、敏感性、特异性分别为50.0%、55.3%、41.7%与95.2%、97.4%、91.7%,两者比较均有统计学差异(P<0.001)。结论超声造影可提高壶腹部病变的显示能力,且有助于病变的良恶性鉴别诊断,对临床指导治疗具有重要价值。  相似文献   
976.
 目的  探讨HIV/AIDS相关Burkitt淋巴瘤(Burkitt lymphoma,BL)的临床病理学形态、免疫表型特点、诊断及其鉴别诊断。方法  按照WHO(2008)造血与淋巴组织肿瘤病理学分类,应用HE染色、免疫组化EnVision法染色、荧光原位杂交(fluorescence in situ hybridization,FISH)及原位杂交并结合临床资料对2010年8月至2013年3月收集的10例HIV/AIDS相关BL进行综合分析。结果  10例患者中活检腋下肿块4例、颈部肿块3例、腹股沟肿块1例、腹部手术切除肿物2例。免疫组化染色瘤细胞均显示IgM、CD20、CD19、CD79a、CD10、Bcl 6阳性,CD5、CD21、CD30、EMA、Bcl 2、CD3、ALK-1、TdT阴性,Ki67增殖指数均>90%,1例表达CD38及MUM-1,3例c-myc阳性,1例LMP-1阳性,突变型p53阳性表达5例。原位杂交EBER 示3例阳性;FISH示C-MYC基因断裂重组8例t(8;14)(q24;q32)。病理诊断:经典型BL 9例,浆细胞样分化BL 1例。结论  HIV-BL为高度恶性淋巴瘤,预后较差,光镜下易与弥漫大B细胞淋巴瘤和淋巴母细胞性淋巴瘤/白血病等相混淆,结合典型病理表现、免疫组化和FISH技术有助于临床病理诊断及其鉴别诊断。  相似文献   
977.
目的探讨大黄贴敷神阙穴和天枢穴联合口服复方聚乙二醇电解质散(PGEP)在便秘患者肠道准备中的给药时机。方法选择行结肠镜检查的便秘患者300例,分3组,各100例。A组检查前1天晚上9点,行中药贴敷神阙穴和天枢穴,检查当天早上5~7点服完PGEP 139.12 g(2 000 ml);B组检查前1天晚上9点行中药贴敷神阙穴和天枢,检查当天上午10~12点服完相同剂量的PGEP;C组检查当天早上5点行中药贴敷神阙穴和天枢穴,早上5~7点服完相同剂量的PGEP。服药后4 h行结肠镜检查。应用Boston肠道准备量表(BBPS)评分,并对肠腔内气泡进行评分,比较3组患者肠道准备有效性、耐受性及安全性。结果 A组的肠镜检查时间(7.25±0.60)min明显短于B组(9.10±0.80)min和C组(10.50±0.55)min;A组的BBPS评分(8.50±0.35)分明显高于B组(7.35±1.25)分和C组(6.65±1.30)分;A组的肠腔内气泡评分(0.25±0.15)分明显低于B组(0.75±0.65)分和C组(0.55±0.50)分;A组肠道准备接受率、再次肠道准备接受率(96.00%、93.00%)明显高于B组(85.00%、70.00%)和C组(90.00%、88.00%);A组的总体不良反应评分(1.45±0.04)分明显低于B组(1.75±0.55)分和C组(1.60±0.25)分。差异均有统计学意义(P0.05)。结论检查前1天晚上9点大黄穴位贴敷联合检查当天早上5~7点口服PGEP对便秘患者行结肠镜检查肠道准备效果好。  相似文献   
978.
BackgroundInflammation can facilitate development of coronavirus disease 2019 (COVID-19) and cardiac injury is associated with worse clinical outcomes. However, data are relatively scarce on the association between hyper-inflammatory response and cardiac injury among COVID-19 patients.MethodsThe study was designed based on severe and critically ill patients with COVID-19. Information on clinical characteristics and laboratory examinations was collected from the electronic medical records and analyzed.ResultsThere were 32.4% (n = 107) of patients with cardiac injury. The median age was 67 years, and 48.8% (n = 161) of patients were men. Hypertension was the most common in 161 (48.8%) patients, followed by diabetes (16.7%, n = 55) and coronary heart disease (13.3%, n = 44). Compared to cases without cardiac injury, those with cardiac injury were older, had higher proportions of coronary heart disease, and leukocyte counts, significantly elevated concentrations of N-terminal pro-B-Type natriuretic peptide, high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor (TNF)-α, interleukin-2 receptor (IL-2R), IL-6, and IL-8, but lower lymphocyte counts. A significant positive correlation was observed between high-sensitivity troponin I and inflammatory cytokines. Logistic regression analysis showed that hs-CRP, TNF-α and IL-6 were independent risk factors for cardiac injury.ConclusionsCardiac injury was associated with elevated levels of inflammatory cytokines among severe and critically ill patients with COVID-19, suggesting that hyper-inflammatory response may involve in cardiac injury.  相似文献   
979.
BackgroundWe performed this meta-analysis evaluating the efficacy of chronotherapy of hypertension with angiotensin receptor blockers (ARBs).MethodsWe searched Pubmed, Web of Science, and Cochrane for all published randomized trials that compare antihypertensive effects of ARBs between bedtime dosing and awakening dosing. Blood pressure (BP) was measured by ambulatory BP monitoring in patients with mild or moderate essential hypertension.ResultsThe effects of ARBs on BP were assessed in 805 essential hypertensive patients included in 8 trials with a follow-up of 12 ± 3 weeks. The sleep-time systolic and diastolic BP (SBP, DBP) with bedtime dosing greatly decreased as compared with awakening dosing (weighted mean differences [WMD] for SBP WMD ?5.23 [95% confidence intervals (CI), ?7.27, ?3.20] mm Hg, p < 0.001; WMD for DBP ?2.94 [95% CI, ?4.52, ?1.36] mm Hg, p < 0.001). The reduction of daytime SBP (WMD 0.98 [95% CI, ?0.20, 2.17] mm Hg, p = 0.10), DBP (WMD 0.11 [95% CI, ?0.68, 0.89] mm Hg, p = 0.79), 24 hour SBP (WMD ?0.75 [95% CI, ?1.93, 0.42] mm Hg, p = 0.21) and DBP (WMD ?0. 77 [95% CI, ?1.55 0.01] mm Hg, p = 0.05) with bedtime dosing was similar with awakening dosing.ConclusionsBedtime dosing with ARBs is more effective in lowering sleep-time BP than awakening dosing in patients with essential hypertension, suggesting a utilization of chronotherapy of hypertension with ARBs to reduce sleep-time high BP. Larger multi-ethnic studies are needed to investigate the efficacy of chronotherapy of hypertension.  相似文献   
980.
Introduction: Patients with schizophrenia or bipolar disorder treated with antipsychotic medication can frequently experience lack of efficacy and persistent side-effects, so much so that switching from one antipsychotic to another with a different side-effect profile has become a recommended strategy for improving the tolerability and safety of long-term antipsychotic treatment. Aripiprazole is an atypical antipsychotic with proven efficacy in schizophrenia and bipolar I disorder, with a pharmacological profile distinct from other available antipsychotics and a side-effect profile that is different from other agents in the class; these characteristics make it a possible alternative in patients requiring a change in antipsychotic treatment due to lack of efficacy or persistent side-effects.

Areas covered: A panel of Italian experts in psychiatry met to discuss the appropriateness of current strategies for the switch to aripiprazole in patients with schizophrenia or bipolar disorder once a clinician has decided to adopt this choice and also to propose alternate strategies where required. The strategies for the switch to aripiprazole presented in this position paper consider various scenarios encountered in clinical practice, highlight the importance of tapering the prior antipsychotic based on its pharmacological characteristics and provide detailed guidance throughout the entire switching process. Literature searches were conducted using the PubMed database and the search strategy (aripiprazole and switching); additional references were added from the reference lists of the papers obtained and also from the authors’ knowledge of the topic.

Expert opinion: Few studies have addressed the indications for antipsychotic switching and the best practical strategies to achieve the desired goal in the clinical practice setting. Studies on antipsychotic switching should clarify why, when and how a switch should be done. The results should standardize the reasons for switching an antipsychotic, assess the optimal time to switch and evaluate the best ways to switch. Both clinical and pharmacological factors should be considered when a patient needs to switch antipsychotics, and specific guidelines for antipsychotic switching that address all these factors are needed.  相似文献   

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