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排序方式: 共有826条查询结果,搜索用时 15 毫秒
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43.
The impact of computed tomography on neuroradiologic practice 总被引:1,自引:0,他引:1
44.
45.
Traumatic diaphragmatic herniation 总被引:3,自引:0,他引:3
Traumatic diaphragmatic hernia is rare in children. Left-sided Herniations are seen in 90%. The diagnosis is often delayed
for months to years because of its rarity and overshadowing injuries. Chest/abdominal radiographs and, in particular cases,
computed tomography and ultrasound improve the accuracy of diagnosis. We report two cases of traumatic diaphragmatic rupture
in children. The history of trauma along with plain X-rays/barium study was diagnostic in both the cases. 相似文献
46.
AR-A014418, a selective GSK-3 inhibitor, produces antidepressant-like effects in the forced swim test 总被引:1,自引:0,他引:1
Gould TD Einat H Bhat R Manji HK 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2004,7(4):387-390
The mechanism by which lithium exerts either its anti-manic or antidepressant effects remains to be fully elucidated. Although lithium inhibits the enzyme glycogen synthase kinase-3 (GSK-3) at concentrations that are relevant for treatment of bipolar disorder, it is unclear whether GSK-3-related mechanisms are responsible for its therapeutic effects in the treatment of this disease. We report that AR-A014418 (a selective GSK-3 inhibitor) induces behavioural changes that are consistent with the effects of antidepressant medications. Subacute intraperitoneal injections of AR-A014418 reduced immobility time in rats exposed to the forced swim test, a well-established model for antidepressant efficacy. In addition, the specificity of this effect is supported by our finding that AR-A014418 decreased spontaneous as well as amphetamine-induced activity. Taken together, these data support the hypothesis that lithium may exert its antidepressant effects through inhibition of GSK-3, and that novel small-molecule GSK-3 inhibitors may be useful for the treatment of bipolar disorder and depression. 相似文献
47.
Neuronal death, attributable to perturbed redox homeostasis, is the underlying factor in many acute and chronic neurological disorders. The mechanisms employed by oxidatively stressed neurons to commit to cell death pathways are beginning to be characterized, but this is hampered by a lack of good models that extrapolate readily to redox-dependent neuronal death paradigms. In this Mini-Review, we discuss mechanisms by which oxidative stress can result in neurodegeneration. We examine evidence on which terminally differentiated neurons might commit to death under conditions of oxidative stress. In some cases, death may be linked to an aberrant and uncoordinated reentry into the cell cycle and mitotic catastrophe. Other evidence suggests that cell cycle reentry is not mandatory for death execution. Rather, the reexpression of cell cycle proteins may induce apoptotic pathways in a cell cycle-independent manner. In contrast to these models, there is also evidence that oxidative neuronal death is independent of cell cycle proteins. We conclude that oxidative stress-induced neuronal death may be promoted via several pathways, which may be cycle protein dependent or independent. The determining factor for which or how many pathways are induced appears to be context dependent and determined by the level and duration of oxidative stress. 相似文献
48.
This work reports the development of new non-thrombogenic polymers based on the linear polymers of polyamidoamines (PAAs), having heparin binding ability, obtained by polyaddition of secondary amines to N,N'-methylene bis-acrylamide. PAAs could not be used directly in the making of blood-contacting materials due to their poor mechanical strength. In order to overcome this lacuna, copolymers of amidoamine with methylmethacrylate (MMA) were prepared. Characterization studies indicated that the PAAs have been suitably incorporated into the MMA matrix. The relative hydrophilic nature of the synthesized copolymers was established from the measurement of water contact angle. The heparinized copolymers showed significant improvement in non-thrombogenic characteristics. 相似文献
49.
Fournier's gangrene in neonates-differences from that in adults 总被引:1,自引:0,他引:1
50.
Optimal reference mammography: a comparison of mammograms obtained 1 and 2 years before the present examination 总被引:3,自引:0,他引:3
Sumkin JH Holbert BL Herrmann JS Hakim CA Ganott MA Poller WR Shah R Hardesty LA Gur D 《AJR. American journal of roentgenology》2003,180(2):343-346
OBJECTIVE: We assessed and compared the benefit of using images acquired 1 year or 2 years previously during mammography interpretations. MATERIALS AND METHODS: Eleven radiologists and one resident reviewed 128 cases three times: once without prior mammograms for comparison, once with mammograms from the most recent (1 year) examination, and once with mammograms acquired 2 years previously. They were asked to determine whether the patient should be recalled for additional procedures. Performances under the three conditions were compared. RESULTS: Radiologists were significantly more accurate (p < 0.001) when comparison mammograms (obtained 1 or 2 years previously) were available. Although sensitivity was not significantly affected between the availability of mammograms from 1 or 2 years earlier (p > 0.10), the specificity was. Specificity using mammograms from the latest examination (obtained 1 year previously) as a reference was significantly better (p = 0.03) than specificity using mammograms obtained 2 years previously. CONCLUSION: Comparison mammograms are important for accurate diagnosis-in particular, for increasing specificity. The latest prior examination seems to be the optimal one for this purpose. 相似文献