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91.
Tracer experiments were carried out to compare the plant uptake behavior of Tc and Re from nutrient solutions. Radish plants, transplanted to nutrient solution including various tracers, showed the same uptake and distribution of 95mTc and 183Re. The trend was the same when the 99Tc and stable-Re concentrations were increased in nutrient solution. The behavior of other elements was different from that of Tc and Re. These findings suggest the possible use of Re as the chemical analogue of Tc in soil solution to plant uptake experiments. 相似文献
92.
胃类癌生物学行为及与预后关系的临床研究 总被引:1,自引:0,他引:1
目的分析胃类癌特有的生物学行为与肿瘤预后之间的关系。方法总结1964年1月至2005年1月间收治的26例经手术切除、病理证实的胃类癌病例资料,对其肿瘤大小、胃壁侵犯深度、区域淋巴结转移、肝转移、术后辅助化疗和5年生存率进行分析。结果本组患者平均年龄58岁。其中18例(69.2%)肿瘤侵犯胃浆膜;12例(46.2%)有区域淋巴结转移;10例(38.5%)术后接受辅助化疗;14例(53.8%)在随访中出现肝转移。肿瘤大小与胃壁侵犯深度、区域淋巴结转移和肝转移的发生及5年生存率无关(P>0.05)。生存分析提示浆膜浸润、淋巴结转移和肝转移影响生存时间(P<0.05)。有浆膜浸润、淋巴结转移和肝转移的患者5年生存率分别为16.7%、16.7%和0,预后较差;化疗与否5年生存率比较,差异无统计学意义(P<0.05)。结论胃类癌术后辅助化疗并无益处,其预后与肿瘤的浸润深度、淋巴结转移和肝转移有关。 相似文献
93.
Kathy Dujardin Pascal Sockeel David Devos Marie Delliaux Pierre Krystkowiak Alain Destée Luc Defebvre 《Movement disorders》2007,22(6):778-784
The objective of this study was to use the Lille Apathy Rating Scale to assess apathy in a large population of Parkinson's disease (PD) patients and identify several different apathy profiles. One hundred fifty-nine patients with probable PD and 58 healthy controls participated in the study. Apathy was assessed using the Lille Apathy Rating Scale. Motor, cognitive, and depressive symptoms were rated on standardized scales. Data were analyzed using linear regression and multivariate analyses of variance. Thirty-two percent of the PD patients were classified as apathetic. Apathy was more frequent in patients with dementia. The four apathy dimensions contributed differently to the overall severity of the apathetic condition. Action initiation and intellectual curiosity had a marked influence. Linear regression analysis revealed that the apathy level was mainly determined by cognitive impairment, not associated with the severity of motor symptoms, and only associated with the apathy subcomponent of the Montgomery and Asberg Depression Rating Scale. Apathy is highly prevalent in PD patients. Apathy profiles vary according to the clinical presentation of PD. The high prevalence of apathy in PD suggests the involvement of frontal-subcortical circuits. Although the neurochemical substrate of apathy remains poorly characterized, the strong link between apathy and cognitive impairment observed in several studies suggests the participation of nondopaminergic circuits. 相似文献
94.
95.
Cognitive Behavior Therapy for Psychotic Disorders: Current Issues and Future Developments 总被引:2,自引:0,他引:2
Nicholas Tarrier 《Clinical psychology》2005,12(1):51-56
There is accumulating evidence, reviewed by Caudiano (this issue), that cognitive behavior therapy (CBT) is an effective adjunct treatment for schizophrenia. Schizophrenia treatment and research provides a range of challenges that are probably not present in other mental health problems. These include contextual issues, clinical issues, scientific and methodological issues, practical and pragmatic issues, public concern, and human rights issues. This paper discusses these issues with emphasis on the clinical and research challenges for the future. 相似文献
96.
大鼠红核和颈段皮质脊髓背侧束联合损伤模型的建立 总被引:3,自引:0,他引:3
目的 为研究脊髓损伤后的可塑性变化 ,建立大鼠红核和皮质脊髓背侧束 (dCST)联合损伤模型。方法 立体定位仪下 ,致伤颈 3dCST和双侧红核 ,甲苯胺蓝染色显示损伤范围。示踪剂观测皮质脊髓腹侧束 (vCST)的出芽情况 ;同时 ,评定大鼠前肢功能的变化情况。结果 精确地致伤红核和dCST后 ,vCST的出芽数量和大鼠前肢功能评分成显著负相关 (P <0 0 1)。结论 大鼠红核和dCST联合损伤模型是研究脊髓损伤后可塑性变化的良好模型 相似文献
97.
低温保存动脉的粘弹性力学评价指标的初步建立 总被引:1,自引:0,他引:1
目的 建立低温保存动脉的粘弹性力学评价指标.方法 使用动态力学分析仪(DMA-2980, TA Instruments, New Castle, Delaware, USA) 比较研究不同低温保存方案下动脉蠕变行为与新鲜对照组的差异.结果 低温保存动脉相对新鲜对照组而言,其粘弹性均有损失;随降温速率的增加(1.5, 5, 10℃/min),其粘弹性损失趋于增加,即1.5℃/min 为本研究中最佳降温速率.结论 粘弹性力学性能是低温保存动脉的潜在的重要评价指标. 相似文献
98.
Jonathan L. Katz Jeffrey M. Witkin Steven I. Dworkin Linda A. Dykstra Richard B. Carter 《Drug development research》1990,20(1):31-41
Effects of daily administrations of d-amphetamine were studied on key peck responses of pigeons maintained under a multiple fixed-interval 2-min, fixed-ratio 30-responseschedule. Under the fixed-interval schedule, a pause was followed by a transition to increasing rates of responding until food presentation. Under the fixed-ratio schedule, higher sustained rates of responding were maintained. Low to intermediate doses (0.3-1.0 mg/kg) of d-amphetamine changed the temporal patterns and occasionally increased rates of responding under the fixed-interval schedule. Higher doses decreased rates of responding under bothschedules. With daily injections of 1.0 mg/kg d-amphetamine prior to experimental sessions, the effects of this dose on rates and patterns of responding were attenuated, and d-anphetamine dose-effect curves were shifted to the right, primarily under the fixed-ratio schedule. Similar results were obtained with daily presession injections of 5.6 mg/kg d-amphetamine in a second group of pigeons, except that rates of responding under both schedules were decreased by this daily dose, and did not return completely to control values with repeated injections. In a third group of pigeons, 1.0 mg/kg d-amphetamine administered daily, after experimental sessions, did not alter dose-effect functions for d-amphetamine. In a second experiment, pigeons were trained to peck one response key when given 1.0 mg/kg d-amphetamine and a different key when given presession water injections. Increasing doses of d-amphetamine produced incresing percentages of d-amphetamine-key responses. Repeated administration of 5.6 mg/kg d-amphetamine shifted these dose-effect functions to the right one-half log unit. Results suggested that decreases in reinforcement frequency are not a necessary condition for the development of behavioral tolerance to d-amphetamine. 相似文献
99.
Contralateral intrastriatal injection of 0.1 pmol or 1 pmol of endothelin-1 produced ipsilateral turning behaviour in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the nigrostriatal pathway. This effect could be abolished by pretreatment with either the endothelinETA/B receptor antagonist bosentan (1 nmol, intrastriatally) or the dopamine D2 receptor antagonist raclopride (0.1 mg/kg, s.c.) suggesting that endothelin is acting at endothelin receptors to evoke ipsilateral turning behaviour and that this response is mediated by dopamine. Similar ipsilateral turning behaviour was observed upon intrastriatal injection of 1 pmol of endothelin-3 or the specific ETB receptor agonist, [Ala1,3,11,15]endothelin-1 when compared to endothelin-1. Pretreatment with the specific ETB receptor antagonist BQ788 blocked the ipsilateral turning response to intrastriatal injection of endothelin-1 while pretreatment with the specific ETA receptor antagonist BQ123 did not significantly change the response to injection of endothelin-1. This indicates that endothelin-1, which has affinity for both ETA and ETB receptors, is most likely acting at the ETB receptor to elicit its effect. These results suggest that low doses of endothelin may act at ETB receptors to evoke the release of dopamine from the striatum in vivo. 相似文献
100.