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排序方式: 共有6523条查询结果,搜索用时 531 毫秒
61.
目的:观察新生儿缺氧缺血性脑病(HIE)心肌酶活性化及心脏受损的情况,方法:采用连续监测法等方法检测了110例新生儿HIE与45例正常新生儿脐血心肌酶谱测定值比较。结果:血清心肌酶谱HIE新生儿组明显高于新生儿正常对照组(P〈0.01),而重度HIE组显高于轻、中度HIE组(P〈0.01)。结论:新生儿HIE做心肌产谱测定是诊断其心肌损害、损害程度和估计预后的临床指标之一,有助于临床早期预测新生儿HIE心肌损害有给予早期治疗。 相似文献
62.
大鼠拟血管性痴呆模型的建立及中药9602防治作用初探 总被引:46,自引:0,他引:46
用反复夹闭双侧颈总动脉(CCA)结合腹腔注射硝普钠将血压降低到50mmHg左右的方法复制了大鼠拟血管性痴呆的模型。结果表明脑缺血再灌注后7 d,行为学实验显示模型组大鼠出现明显的学习记忆障碍;形态学观察发现海马CA1区出现明显的细胞缺失,而CA3区无明显变化。中药9602可明显减轻脑缺血对海马的损伤,改善脑缺血引起的学习记忆障碍的作用。 相似文献
63.
目的:研究KATP通道在离体大鼠心脏缺血预处理中的作用。方法:取雄性SD大鼠心脏行Langendorff灌流。以3m in 全心缺血加5m in 复灌重复3次为预处理,灌流30 m in 作为对照,同时灌以KATP通道阻断剂优降糖(10 μm ol/L)或开放剂吡那地尔(50 μm ol/L)。然后以结扎左冠状动脉20 m in,复灌60 m in 作为缺血复灌,以心肌梗塞范围和心律失常评分作为指标,观察药物对预处理的心肌保护作用的影响。结果:优降糖可阻断缺血预处理的作用,而吡那地尔则不能模拟缺血预处理,但是在缺血期间吡那地尔对心肌有保护作用。结论:KATP通道很可能参与了大鼠心肌缺血预处理的心肌保护机制,但不是触发因素 相似文献
64.
中西医结合治疗成人股骨头缺血坏死120例 总被引:7,自引:0,他引:7
采用中西医结合疗法 ,经皮股骨头内减压引流、靶血管脉冲式加压药物灌注、髂内动脉部分血管栓塞灌药和口服中药治疗成人股骨头缺血坏死 12 0例。通过 12~ 36个月的随访观察 ,髋关节疼痛缓解率为 92 5 0 % ,关节活动度改变率为 96 67% ,DSA检查血管增加达 88 33% ,CT、X线片股骨头骨质改变占 5 5 83%。综合疗效优于任何单项治疗 相似文献
65.
L. W. Jenkins J. T. Povlishock W. Lewelt J. D. Miller D. P. Becker 《Acta neuropathologica》1981,55(3):205-220
Summary The neuronal response to complete cerebral ischemia (CCI) of 5–15 min duration was evaluated at the light and electron microscopic level subsequent to postischemic recirculation periods of up to 60 min. Following postischemic reperfusion, the homogeneous neuronal changes characteristic of permanent CCI were modified into a heterogeneous pattern of selectively vulnerable neuronal responses. Four basic types of neuronal injury were represented within this heterogeneous neuronal population. The Type I neuronal response was most numerous and consisted of chromatin clumping, nucleolar condensation and a breakdown of polysomes. This response may represent a reversal of some of the neuronal changes observed after permanent CCI. In addition to the above changes, Type II neurons contained swollen mitochondria and Golgi saccules which appeared as microvacuoles under the light microscope. Type III neurons displayed varying degrees of neuronal shrinkage and numerous swollen mitochondria. Type IV neurons were markedly shrunken and electron-dense with few identifiable subcellular structures. The distribution of Type I neurons was random but the other neuronal responses occurred in selectively vulnerable brain regions. The number of Type II, III, and IV neurons increased with extended insult durations but were unaffected by the length of recirculation. Ten minutes of CCI represented the threshold for a significant increase in the number of severely altered neurons. These findings suggest that considerable neuronal injury may be present after 10–15 min of CCI, and the lack of a recirculation period following CCI appears to afford the brain parenchyma an extensive degree of structural protection.Supported by PHS Grant NS-12587 相似文献
66.
67.
目的 观察化痰通络汤对缺血性中风恢复期风痰瘀阻证的临床疗效.方法 将57例缺血性中风恢复期风痰瘀阻证患者随机分为两组,治疗组29例采用化痰通络汤治疗,对照组28例采用消栓通络胶囊治疗,治疗8周后评价临床疗效.结果 两组患者治疗后神经功能缺损评分均得到明显改善(P<0.01),且治疗组优于对照组(P<0.05):治疗组的临床疗效及显效率优于对照组(P<0.05).结论 化痰通络汤治疗缺血性中风恢复期风痰瘀阻证有效. 相似文献
68.
Talavera JO Wacher NH Laredo F López A Martínez V González J Lifshitz A Feinstein AR 《Archives of medical research》2000,31(6):576-584
BACKGROUND: When a CT scan is not available, an early accurate clinical diagnosis of ischemic stroke is essential to initiate prompt therapy. Our objective was to construct a clinical index that is easy to use when stroke patients are first evaluated at the hospital, to identify those who probably are experiencing an acute ischemic episode. The study was conducted at a university-affiliated medical referral center and two community general hospitals in Mexico. METHODS: Clinical records were reviewed for 801 patients with sudden onset of a focal or global neurologic dysfunction, presumably of vascular origin lasting more than 24 h. Eligibility criteria for this study were admission to the hospital within the first 24 h after symptomatic onset, CT scan diagnosis between 24 and 72 h, and age >45 years. Ischemic stroke included cases of arterial brain infarction, while nonischemic stroke included subarachnoid or intraparenchymatous hemorrhage, mass lesion, venous infarction, and in cases without a CT scan evidence that could explain the clinical manifestations. Data excerpted for analysis were age, sex, history of diabetes mellitus or previous stroke/transient ischemic attack (TIA), time of onset of symptoms, presence of headache, vomiting, neck stiffness, hemiplegia, leukocytosis or atrial fibrillation, diastolic blood pressure, and Glasgow coma scale (GCS) rating. Two multivariable analyses were used: 1) step-wise multiple logistic regression (SMLR), and 2) conjunctive consolidation (CC). RESULTS: After appropriate exclusions, the study proceeded with 83 ischemic and 42 nonischemic stroke patients. With SMLR, six variables were selected as predictive for ischemic stroke, including neck stiffness, diastolic blood pressure, previous history of stroke/TIA, hemiplegia, GCS, and atrial fibrillation. An appropriate sum of weighted ratings had a positive predictive value (PPV) of 100% for ischemic stroke. With consolidated categories, the PPV was 97% when patients had the following: no neck stiffness; no atrial fibrillation but history of stroke/TIA and GCS > or =12, or no neck stiffness but atrial fibrillation. CONCLUSIONS: Among patients with acute stroke, clinical data can be used to identify a group with a high probability of ischemic stroke. There are slightly different results between both methods; while SMLR includes the four variables selected by CC, the latter included neither diastolic blood pressure nor hemiplegia/hemiparesia. However, CC results seem easier to understand and interpret than with SMLR. 相似文献
69.
70.
目的 研究心脏和肾脏短暂缺血预处理对急性心肌梗死(AMI)后心律失常的影响。方法 观察AMI组(A组)、心脏缺血预处理(MIP)组(B组)和肾脏缺血预处理(RIP)组(C组)新西兰兔在AMI前后的心律失常情况及QT间期离散度(QTd) ,并行心内电生理诱发室性心动过速(VT) ,对三组的指标进行比较,同时设置假手术组(D组)作对照。结果 四组在手术前心律失常及QTd差异无显著意义(P >0 . 0 5 ) ;D组手术前后心律失常及QTd比较差异无显著意义(P >0 . 0 5 ) ;在AMI后,B、C两组室性心律失常及QTd明显小于A组(P <0 . 0 5 ) ,而B、C两组室性心律失常及QTd比较差异无显著意义(P >0 .0 5 )。结论 MIP和RIP均可减少AMI后室性心律失常的发生,而且两者的作用没有明显差异。 相似文献