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71.
牛磺酸对实验性高血压大鼠脑脊液和血浆内皮素含量的影响 总被引:4,自引:0,他引:4
目的探讨牛磺酸对实验性高血压大鼠脑脊液、血浆内皮素-1(ET-1)含量的影响.方法Wistar大鼠36只,随机分为高血压组,牛磺酸组和对照组3组,高血压组和牛磺酸组建立大鼠主动脉狭窄-高盐摄入性高血压模型,牛磺酸组饲料中加牛磺酸,观察3组大鼠脑脊液、血浆ET-1含量及血压的变化,测定脑组织和主动脉组织牛磺酸含量及主动脉肌条的舒缩功能.结果应用牛磺酸后,高血压大鼠pMA,脑脊液和血浆ET-1水平均下降(P<0.05),血管舒缩功能得以改善.结论牛磺酸可降低脑脊液、血浆ET-1水平,从而降低血压. 相似文献
72.
L- Tetrahydropalmatine (L- THP) ,a kind of al-kaloid extracted from traditional Chinese medicineRhizoma corydalis,posseses sedative,analgesic andhypnotic effects.Recently,it has been demonstratedthat L- THPalso had calcium- antagonistic and antiar-rythmic effects.Studies showed that L- THP had aprotective effect on acute focal and global cerebral is-chemia- reperfusion injury[1,2 ] .Many studies provedthat the production of NO wasincreased significantlyduring ischemia- reperfusion.The o… 相似文献
73.
益母草防治初发期急性肾小管坏死的实验研究 总被引:13,自引:3,他引:10
SD成年雄性大鼠,禁止16小时,肌注甘油引起急性肾小管坏死(ATN),于其初发期给予不同药液,观察到益母草组3、24及48小时Bcr升高值,24及48小时BUN升高值均明显低于自来水组和单纯禁水组,而与校正对照异搏停组近似,肾组织损伤程度亦明显减轻。结果表明,益母草对初发期急性肾小管坏死(IATN)有一定的防治作用。 相似文献
74.
J Staessen A Bernard J P Buchet F Claeys L Dekempeneer G Ducoffre R Fagard R Lauwerys P Lijnen H Roels 《IARC scientific publications》1992,(118):263-269
This paper summarizes the findings of the Cadmibel Study, a cross-sectional population study of the health effects of cadmium, but only with respect to the cardiovascular system and calcium metabolism. The study disproved the hypothesis that exposure to cadmium would lead to an increase in blood pressure and in the prevalence of hypertension and other cardiovascular diseases. On the other hand, there was a positive relationship between urinary cadmium (Cd-U) and both serum alkaline phosphatase activity and urinary excretion of calcium. The regression coefficients obtained after adjustment for significant co-variates indicated that, when Cd-U increased two-fold, serum alkaline phosphatase and urinary calcium rose by 4% and 0.25 mmol/24 h, respectively. These findings suggest that calcium metabolism is gradually affected as cadmium accumulates in the body. The morbidity associated with the latter phenomenon is still unknown, and requires further investigation, preferably in a longitudinal prospective population study, in which the incidence of morbid events would be monitored in relation to the cadmium body burden. 相似文献
75.
The expression of both high-affinity E receptor (EhR) to sheep erythrocytes and CD2-11.3 epitope on activated human T lymphocytes suggests that these two structures may be functionally identical or closely associated. Therefore the aim of the present work was to determine if the CD2-11.3 epitope is involved in the early E rosette formation. The ability of normal and phytohaemagglutin (PHA)-activated human T lymphocytes to express the CD2-11.3 epitope and to form early E rosettes (T cells with EhR) was studied simultaneously. The partial divergence of CD2-11.3 expression on T lymphocytes from the ability of these cells to form early E (Ee) rosettes was found. The results indicated that the expression of CD2-11.3 epitope alone is insufficient to form the Ee rosettes by activated T lymphocytes, yet it may facilitate this phenomenon in the presence of EhR. The above data clearly show that the CD2-11.3 epitope is functionally closely associated although not identical to EhR. Accordingly, it seems that these two structures may co-adhere to the appropriate ligand. Thus it is possible that the CD2-11.3 epitope, as well as its established role in activation signalling, may also act as a co-adhesion molecule. 相似文献
76.
《Alzheimer's & dementia》2007,3(3):204-210
BackgroundThe purpose of this study was to examine the direct costs of care for patients newly diagnosed with Alzheimer’s disease (AD) by using retrospective healthcare claims data.MethodsPatients aged 65 years or older with ≥1 claims containing a listed diagnosis of AD between January 1999 and November 2003 were selected. The first observed AD claim was deemed the index date. Control patients with no evidence of AD or dementia also were identified. Patients had a 12-month pre-index period and minimum 30-day follow-up. AD patients were matched to control patients on the basis of age, gender, and follow-up duration. Annualized utilization and costs were calculated; generalized linear models (GLM) were undertaken, controlling for demographic and clinical characteristics. Analyses focused on differences in costs among AD patients and controls.ResultsThe average age of AD and control patients was 82 years; 38% were men (n = 2,475 AD; 4,950 controls). Average total costs for AD patients were more than five-fold higher compared with controls ($28,263 vs $5,880; P < .001), driven primarily by inpatient costs. Total costs were significantly higher (P < .001) for AD patients in GLM modeling, with diagnosis group (AD vs control) as the most important predictor. Adjusted annual costs per patient were also five-fold higher ($21,150 vs $4,053 for AD vs control, respectively) during the follow-up period.ConclusionsThe annual economic burden of AD to third-party payers is more substantial than previously estimated ($3,805 to $8,200). 相似文献
77.
Control of movement depends on the continuous release of dopamine by neurons in the basal ganglia of the brain. The degeneration of these neurons in Parkinson's disease (PD) interferes with the flow of dopamine, leading to classic motor symptoms. In early PD, enough dopaminergic neurons remain to store dopamine provided by periodic dosing with oral levodopa and relatively normal, tonic levels of dopamine release are maintained. PD progression leads to degeneration of remaining dopaminergic terminals and loss of buffering capacity for exogenous levodopa. As a result, there are supraphysiological levels of dopamine after dosing and troughs when the available dopamine has been depleted. These divergent levels are associated with dyskinesia and ‘off’ states, respectively. Treatment strategies that provide a continuous flow of dopamine and can thus mimic normal physiological dopamine stimulation have potential to improve motor control for patients with advanced PD. 相似文献
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本实验通过结扎沙土鼠双侧颈总动脉20分钟,再灌流7天内,动态观察背侧海马组织的形态学变化。光镜观察表明:海马各区对缺血的反应性不同,其中以 CA_1区锥体细胞对缺血最为敏感,并且 CA_1区神经元的损伤是迟发性的,再灌流4天后才出现大量神经元的坏死、消失,即“迟发性神经元死亡”(NDN)。电镜下发现:缺血再灌流早期(1~2天),CA_1区神经细胞质内有大量粗面内质网增多。本实验结果表明:短暂性脑缺血所致的海马损伤与脑组织其他区域神经元损伤不同。 相似文献