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991.
The study used a naturally occurring crosslinking reagent-genipin to chemically modify acellular bovine pericardium, prepare cardiac valve tissue engineering scaffold material,and evaluated genipin crosslinked acellular matrix of bovine pericardium by investigating the physical and chemical properties of the tissues, such as the surface properties, crosslinking characteristics, mechanical properties, resistance to enzymatic capacity in vitro, and hemolysis tests. The results showed that acellular bovine pericardium matrix crosslinked with genipin was strong hydrophilicity, high crosslinking index, and stable structure, which can maintain good mechanical properties. As a kind of scaffold material for valve tissue engineering, it has wide application prospect. 相似文献
992.
目的研究脂肪组织在中等应变率下本构模型及其参数反求。方法基于脂肪组织力学性能实验,通过有限元方法重构脂肪组织压缩实验,并对常见表征脂肪组织的本构模型进行参数筛选。结合最优化方法中的可行方向法(method of feasible direction,MFD),进行中应变率下脂肪组织本构模型相关参数的反求。结果中应变率(260 s~(-1))下黏弹性本构模型相比Ogden本构模型更适合表征脂肪组织的力学响应,并反求得到适用于仿真的本构模型参数。结论中等应变率下黏弹性本构模型更适合表征脂肪组织力学响应。研究结果为汽车碰撞有限元仿真中探究人体脂肪组织对人体损伤的影响提供参考。 相似文献
993.
994.
Geelen E Van Hoyweghen I Doevendans PA Marcelis CL Horstman K 《American journal of medical genetics. Part A》2011,155(8):1930-1938
Professional guidelines on genetic testing of children have recently shifted their focus from protecting the child's autonomous choice to professionals, together with parents, striving to work in the child's “best interest.” This notion of “best interest” allows room for therapeutical as well as psychological and social considerations, and gives rise to the question how parents and professionals weigh up the child's best interest in practice. In this qualitative study, we followed six extended families involved in genetic testing for hypertrophic cardiomyopathy in the Netherlands for 3½ years. In total 57 members of these families were interviewed in depth; many of them more than once. Our empirical analysis shows that the best interest of a child is constructed via long‐term processes in the broader context of family and kin. In this context, “best interests” are considered and reconsidered. We conclude that a child's best interest should not be framed as the result of an instantaneous agreement between parents and professionals. In dealing with genetic testing of children, parents as well as professionals reflect on and learn from the processes of generating new meanings of “best interest.” To enable professionals to deal with the variety in family life, these learning processes should be documented closely. © 2011 Wiley‐Liss, Inc. 相似文献
995.
Ajay Gupta Deepak Govil Shaleen Bhatnagar Sachin Gupta Jyoti Goyal Sweta Patel Himanshu Baweja 《Indian Journal of Critical Care Medicine》2011,15(2):108-113
Objective:
To determine the effects of parenteral omega 3 fatty acids (10% fatty acids) on respiratory parameters and outcome in ventilated patients with acute lung injury.Measurements and Main Results:
Patients were randomized into two groups – one receiving standard isonitrogenous isocaloric enteral diet and the second receiving standard diet supplemented with parenteral omega 3 fatty acids (Omegaven, Fresenius Kabi) for 14 days. Patients demographics, APACHE IV, Nutritional assessment and admission category was noted at the time of admission. No significant difference was found in nutritional variables (BMI, Albumin). Compared with baseline PaO2/FiO2 ratio (control vs. drug group: 199 ± 124 vs. 145 ± 100; P = 0.06), by days 4, 7, and 14, patients receiving the drug did not show a significant improvement in oxygenation (PaO2/FiO2: 151.83 ± 80.19 vs. 177.19 ± 94.05; P = 0.26, 145.20 ± 109.5 vs. 159.48 ± 109.89; P = 0.61 and 95.97 ± 141.72 vs. 128.97 ± 140.35; P = 0.36). However, the change in oxygenation from baseline to day 14 was significantly better in the intervention as compared to control group (145/129 vs. 199/95; P < 0.0004). There was no significant difference in the length of ventilation (LOV) and length of ICU stay (LOS). There was no difference in survival at 28 days. Also, there was no significant difference in the length of ventilation and ICU stay in the survivors group as compared to the non survivors group.Conclusions:
In ventilated patients with acute respiratory distress syndrome, intravenous Omega 3 fatty acids alone do not improve ventilation, length of ICU stay, or survival. 相似文献996.
McDonald J Damjanovich K Millson A Wooderchak W Chibuk JM Stevenson DA Gedge F Bayrak-Toydemir P 《Clinical genetics》2011,79(4):335-344
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant vascular disorder characterized by a unique pattern of telangiectasia and arteriovenous malformations (AVMs). Mutations in one of two genes (ENG and ACVRL1) cause approximately 85% of cases. Genetic testing impacts clinical management because genotype/phenotype correlations exist, and early preventive screening for internal AVMs is recommended in affected individuals prior to the age at which a diagnosis can typically be made based on clinical criteria. We report 383 consecutive cases in which sequencing and large deletion/duplication analysis were performed simultaneously for endoglin (ENG) and activin-like receptor kinase 1 (ACVRL1). We report the first case of mosaicism in an affected individual and 61 novel mutations. We discuss the potential benefits of a diagnostic testing approach for HHT whereby ENG and ACVRL1 are analyzed simultaneously by sequencing and a method which detects large deletion/duplications, rather than by a sequential or reflex testing protocol. We report a case in which a deletion would probably have been missed if large deletion/duplication analysis was performed only if a suspected pathogenic mutation was not first identified by sequencing. 相似文献
997.
998.
目的 使用分子线性探针杂交技术结合仪器法液体快速培养分析耐多药( multidrug resistant,MDR)及广泛耐药(extensively drug resistant,XDR)结核分枝杆菌(Mycobacterium tuberculosis,MTB)的耐药基因和表型特征.方法 运用GenoType MTBDR试剂盒检测M/XDR-TB菌株中各耐药基因的突变位点及类型,平行用BD MGIT960系统检测所选菌株对一线及二线抗结核药物的敏感性.结果 (1)94株MDR-TB经MGIT960检测,乙胺丁醇(ethambutol,EMB)、阿米卡星(amikacin,AMK)、氧氟沙星(ofloxacin,OFX)及莫西沙星(moxifloxacin,MFX)的耐药率分别为36.2%、17.0%、54.3%和55.3%.XDR-TB检出率为13.8%.(2)以MGIT960药敏结果作为参考标准,94株MDR-TB中,GenoType MTBDRplus检测MTB对异烟肼(isoniazid,INH)、利福平(rifampin,RFP)耐药的符合率分别为86.2%和95.7%;GenoType MTBDRsl检测MTB对EMB、AMK、OFX及MFX耐药的敏感性分别为47.1%、81.3%、94.1%、94.2%;特异性分别为75.0%、98.7%、90.7%、92.9%.(3)rpoB基因突变中以S531L最多;INH耐药主要由katG基因发生突变导致,以S315T1类型居多;gyrA突变位点主要集中在第94位密码子.所测菌株中有23例为复合耐药,7例为未知突变.结论 M/XDR-TB中,INH、RFP、AMK、OFX及MFX耐药株大多分别是由katG、rpoB、rrs及gyrA突变导致,乙胺丁醇与embB之间的耐药关联性相对较低.GenoType MTBDR试剂盒检测M/XDR-TB敏感性和特异性较好,可以在未获得传统细菌表型药敏结果前指导临床用药治疗. 相似文献
999.
1000.
Background The frequency of adults reporting a history of asthma is rising. However, it is unclear whether this increased prevalence accurately demonstrates a rising trend or if it reflects an overall increase in asthma awareness. Objective To determine the frequency of negative methacholine bronchoprovocation tests in adults who report physician‐diagnosed asthma and to explore the clinical characteristics of subjects with negative tests. Methods Data from methacholine challenge, spirometry, and physician assessment were analysed from 304 adults who reported physician‐diagnosed asthma and responded to community‐based advertising for asthma research studies. The clinical characteristics of methacholine‐positive and ‐negative subjects were compared and a predictive model was tested to identify those characteristics associated with a negative test. Results Of the 304 subjects tested, 83 (27%) had a negative methacholine test. A negative test was positively associated with an adult‐onset of symptoms (P<0.001), normal forced expiratory volume in 1 s (P<0.001), and having no history of exacerbation requiring oral steroids (P=0.03). Over half (60%) of those with a negative test reported weekly asthma‐like symptoms (cough, dyspnoea, chest tightness, or wheeze), while 39% reported emergency department visits for asthma‐like symptoms. Conclusions and clinical relevance A sizeable percentage of subjects who report physician‐diagnosed asthma have a negative methacholine challenge test. These subjects are characterized by diagnosis of asthma as an adult and by normal or near normal spirometry. Caution should be exercised in the assessment and diagnosis of adults presenting with asthma‐like symptoms, because they may not have asthma. Further diagnostic studies, including bronchoprovocation testing, are warranted in this patient group, especially if their spirometry is normal. Cite this as: K. W. McGrath and J. V. Fahy, Clinical & Experimental Allergy, 2011 (41) 46–51. 相似文献