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81.
破坏泛素依赖的蛋白水解通路对p53转录激活的抑制作用 总被引:1,自引:0,他引:1
目的 :研究功能性泛素化及蛋白酶体水解过程对p5 3转录激活的影响。方法 :通过瞬时转染报告基因法 ,测定内源、外源性p5 3或p5 3转录活性片断的转录能力 (荧光素酶活性 ) ;Western blot法测定细胞内p5 3及其靶蛋白p2 1waf1 的表达水平。结果 :抑制蛋白酶体水解过程 ,细胞内源、外源性p5 3及p5 3转录活性片断的转录能力均降低 ;泛素化途径缺失时 ,p5 3转录能力被显著抑制 ,虽然细胞内p5 3蛋白堆积 ,但其下游靶蛋白p2 1waf1 的表达却无增加。结论 :p5 3泛素蛋白酶体水解途径与其转录激活过程存在功能性联系 相似文献
82.
Digital and conventional chest images: observer performance with Film Digital Radiography System 总被引:5,自引:0,他引:5
The Film Digital Radiography System (FilmDRS) is a device with a laser optical film digitizer, 2,000 X 2,000 X 12-bit memory, and a 1,000-line video display. To evaluate the adequacy of this device for general radiography of the chest, four readers independently analyzed both radiographs and the corresponding video display of the digitized chest images of 150 patients, consisting of 100 images of abnormalities and 50 normal images. The overall results indicate equal sensitivity for the two systems. The FilmDRS, with interactive windowing, proved superior in the detection of hilar and mediastinal disease. X-ray film was superior in allowing detection of hyperlucent states. There was equivalent sensitivity for other disease categories. Superior specificity was achieved with conventional radiographs. 相似文献
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85.
Okada AA; Keino H; Suzuki J; Sakai J; Usui M; Mizuguchi J 《International immunology》1998,10(12):1917-1922
The systemic administration of IFN-alpha/beta was previously found to
suppress inflammation in rats with experimental autoimmune uveoretinitis
(EAU); however, an effect on the systemic immune response was not
identified. In order to investigate an immunological basis for suppression
at the intraocular level, rats immunized with interphotoreceptor
retinoid-binding protein (IRBP) were administered daily intramuscular
injections of 10(5) IU IFN-alpha/beta and cytokines were measured by ELISA
in intraocular extracts prepared by ultrasonification at various timepoints
throughout the course of EAU. In control EAU, intraocular concentrations of
IFN-gamma were found to be non-detectable on day 8 before the onset of
inflammation, significantly elevated on day 12 at peak inflammation
(182+/-106 pg/ml), then non-detectable again on day 16 after inflammation
had begun to subside. In contrast, intraocular IFN-gamma in IFN-alpha/beta-
treated rats remained non-detectable or low at all timepoints. Measurement
of intraocular IL-2 revealed no difference between the two groups of rats.
Intraocular IL-4 concentrations were elevated in rats treated with
IFN-alpha/beta, although this cytokine was also detected in the same range
in controls as well as normal rats. Finally, intraocular IL-10 was
non-detectable on day 8, significantly elevated at peak inflammation on day
12 (588+/-139 pg/ml), then decreased to low levels on day 16 in control EAU
rats, while remaining non-detectable or low in IFN-alpha/beta-treated rats.
These results suggest that acute inflammation in IRBP-induced EAU in rats
involves both IFN-gamma and IL- 10 at the local intraocular level, and that
systemic administration of IFN-alpha/beta inhibits EAU via a mechanism that
involves suppression of both cytokines.
相似文献
86.
Stéphanie F. Bernatchez PhD ; Patrick J. Parks MD PhD ; Duane M. Grussing SRS ; Shawn L. Matalas CVT ; Gwen S. Nelson AA 《Wound repair and regeneration》1998,6(3):223-233
Chronic wounds, such as venous ulcers and pressure ulcers, frequently remain unresponsive to currently available treatments. Several animal models of wound healing have been published, including models of impaired healing developed to mimic the clinical condition of chronic wounds better. We used a delayed wound healing model in the pig that uses irradiation of the skin prior to creation of the surgical wounds and characterized it histologically. Radiation was used on one side of the back prior to making four full-thickness wounds on each side. Clinical observations were performed to record granulation tissue, reepithelialization, and wound area as a function of time. Histology data were obtained at 1, 2, 3, and 4 weeks, and slides were stained with hematoxylin and eosin for general observations. Immunohistochemistry was performed using laminin as a marker for blood vessels, and the number, size, and circularity of blood vessels found in the granulation tissue were measured. Our results show that this model causes a delay in wound healing that is mostly apparent between days 7 and 15. Granulation tissue took more time to form and fill the wounds on the irradiated side, and blood vessels were slower to develop. Blood vessels were larger and more irregular in shape on the irradiated side than on the control side. After 2 weeks, healing resumed, indicating that the induced damage was not irreversible. These results suggest that this model can be used to test the effects of therapeutic approaches intended to treat chronic wounds. 相似文献
87.
N. Dzimiri S. Hussain A. Moorji G. Prabhakar S. Bakr M. Kumar AA Almotrefi and Z. Halees 《Fundamental & clinical pharmacology》1995,9(4):372-380
Summary— In order to test whether the β-adrenoceptor activity in rheumatic heart valvular disease depends on the ventricular load conditions, we determined their density and binding affinity to [125 I]-iodocyanopindolol in lymphocytes, as well as plasma catecholamine and cAMP levels in 69 patients with regurgitant and stenotic lesions of the aortic and mitral valves. The patients were classified as having left ventricular pressure overload (LVP), left ventricular volume overload (LVV), mixed lesions (MOL) or right ventricular pressure overload (RVP). The β-adrenoceptor activity was determined by radioligand binding methods, catecholamines by high performance liquid chromatography using an electrochemical detector and cAMP by radioimmunoassay. The mean β-adrenoceptor density (Bmax ) of the control group was 60.1 ± 9.5 /mol ( n = 29) per 106 lymphocytes. In the study population, the density was decreased by 83% in LVP, 78% in LVV, 87% in MOL and 86% in RVP. Plasma norepinephrine was elevated by 89% in LVP and 60% in MOL, epinephrine by 43% in LVP, 50% in VOL, 115% in MOL and 20% in RVP, while dopamine was not significantly changed, and cAMP was slightly elevated in all four groups. Screening for activating mutational changes in the Gsα -protein gave negative results, possibly dissociating the elevation in plasma cAMP from stimulatory effects of such abnormalities in the Gs -protein signaling. These results show a significant attenuation in lymphocyte β-adrenoceptor density of patients with rheumatic heart valvular disease, irrespective of the type of the prevailing ventricular load conditions. The reduction in receptor density is accompanied by a significant increase in plasma norepinephrine levels in patients with a left ventricular pressure overload and epinephrine in those with volume overload. 相似文献
88.
V. J
NSSON E. HIPPE O. J. CLEMMENSEN E. BADSBERG AA. VIDEBK 《European journal of haematology》1982,29(4):295-298
A mixed B-cell type centroblastic lymphoma with extraordinarily many histiocytes in a 68-year-old man is reported. Multiple skin tumours were the only clinical manifestation during the first 5 months. The disease then progressed to the lymph nodes, spleen, and parenchymal organs, but the bone marrow remained unaffected until death, 11 months after the onset of signs. C3d receptors were the only surface markers of the centroblasts. The histiocytes were normal with respect to morphology, muramidase staining, and Fc and C3b receptors. This highly unusual spread from skin to lymphoid and parenchymal organs is discussed in the light of lymphoid cell kinetics. 相似文献
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90.