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991.
Cytoarchitectonic delineation of areas in post-mortem human brains provides the precise location of these areas. It has been
possible to study the size and location of areas between post-mortem brains with multi-subject cytoarchitectonic data. If
the structure–function relationship is assumed to be a one-to-one mapping for the purposes of inter-subject variability, then
functional areas in the cortex will also adhere to the structure, and therefore, the location and size of cytoarchitectonic
areas in the brain. Thus, it is possible to use the cytoarchitectonic data as being representative of the size and location
of functional activations. Under this assumption, we simulated activations in cytoarchitectonic areas from ten post-mortem
brains in this study. We then treated these data as we would a normal PET experiment. The purpose of this study is to demonstrate
a standard PET image analysis on a simulated ten-subject PET study using cytoarchitecture to localize the activations. By
doing so, we simulate activations with real inter-subject variability with the size and location of each area. Significant
activations were obtained for activations simulated in areas 3a and 3b. A voxel-wise conjunction between simulated data and
experimental data was made to better determine the underlying areas activated by the experimental tasks. This study presents
a novel technique for demonstrating the effect of standard image analysis on the location and size of simulated activations
as determined by cytoarchitectonic data from multiple subjects. Furthermore, this technique has been applied to better determine
the underlying areas activated in an experiment. 相似文献
992.
Kenji Matsumoto Oh-Yong Kwon Hyungtae Kim Yukihiro Akao 《Developmental dynamics》2005,233(3):1149-1156
rck/p54 is a DEAD-box RNA helicase protein with ATP-dependent RNA-unwinding activity. Its ortholog is required for sexual reproduction in yeast and for oocyte survival and sperm fertility in Caenorhabditis elegans. In the current study, we investigated the expression of rck/p54 in mouse gametogenesis and early embryogenesis. Western blot analysis revealed that rck/p54 was highly expressed in both the ovary and testis. In the ovary, maturing oocytes strongly expressed rck/p54 in their cytoplasm. In contrast, in the testis, spermatogonia and primary spermatocytes highly expressed rck/p54 in their cytoplasm, but its expression decreased in the spermatids. Interestingly, rck/p54 was concentrated in the heads of spermatozoa; and then its expression gradually decreased as these cells matured along the epididymal duct. After fertilization, rck/p54 protein and its mRNA remained present in the pronucleus phase; and then their expression levels slightly but definitely decreased in morulae and blastocytes. The injection of a CMV-based rck/p54 expression vector into the pronuclei of fertilized eggs caused a delay in early embryogenesis. In generating RCK transgenic mice, the birth rate of the mice was significantly lower than those of other gene transgenic mice. These findings indicate that rck/p54 may play an important role in gametogenesis and early embryogenesis in mammals. 相似文献
993.
Lee J Lee EN Kim EY Park HJ Chang CY Jung DY Choi SY Lee SK Lee KW Kwon GY Joh JW Kim SJ 《Immunology letters》2005,101(2):210-216
4-1BB (CDw 137), a member of the tumor necrosis factor receptor (TNFR) superfamily, is a costimulatory receptor primarily expressed on activated T cells. It has been shown that the administration of agonistic anti-4-1BB monoclonal antibody (mAb) enhances tumor immunity and allogenic immune responses. Paradoxically, we found that the administration of anti-4-1BB mAb reduced the incidence and severity of inflammatory bowel disease. In this study, we investigated the effects of anti-4-1BB mAb in a murine intestinal inflammation model, which induced by the hapten reagent, 2,4,6-trinitrobenzene sulfonic acid (TNBS) and mimics immunologic characteristics of human Crohn's disease (CD). Colitis was induced by rectal administration of 2mg of TNBS in 35% ethanol using a vinyl catheter positioned 4cm from the anus. All mice were sacrificed 3 and 10 days after the TNBS administration. The disease activity index (DAI), histological changes of the colon and production of cytokines (IL-2, IL-4, IL-10 and IFN-gamma) were evaluated. The surface molecules of T cells in peripheral blood, spleen and mesenteric lymph nodes were analyzed by flow cytometry. When mice were treated with anti-4-1BB mAb, improvement in both wasting and histopathologic signs of colonic inflammation was observed. The increase a number of splenic CD4(+)CD25(+) T cells and decreased synthesis of the Th1 cytokine IL-2 also occurred. Interestingly, increased production of Th1 cytokine IFN-gamma and proportion of CD8(+) T cells were observed in mice treated with anti-4-1BB mAb in comparison to the colitic mice. These studies show, for the first time, that agonistic anti-4-1BB mAb can improve experimental colitis by reduction of IL-2 and augmentation of CD4(+)CD25(+) regulatory T cells. TNBS colitis is Th1-mediated and has similar histologic features and distribution of inflammation to CD. This study suggests that anti-4-1BB mAb therapy could be effective in the treatment of patients with CD. 相似文献
994.
Claes Lundsteen Beth Bjerregaard Erik Granum John Philip Kim Philip 《Clinical genetics》1980,17(3):183-190
995.
996.
Seung Eun Lee Jin-Young Jang Kuhn Uk Lee Sun-Whe Kim 《Journal of Korean medical science》2008,23(6):1011-1014
The spleen may be preserved during distal pancreatectomy (DP) for benign disease. The aim of this study was to compare the perioperative and postoperative courses of patients with conventional DP and spleen-preserving distal pancreatectomy (SPDP) for benign lesions or tumors with low-grade malignant potential occurred at the body or tail of the pancreas. A retrospective analysis was performed for the hospital records of all the patients undergoing DP and SPDP between January 1995 and April 2006. One-hundred forty-three patients underwent DP and 37 patients underwent SPDP. There were no significant differences in age, sex, indications of operation, estimated blood loss, operative time, and postoperative hospital stay between the two groups. Pancreatic fistula occurred in 21 (13.3%) patients following DP and in 3 (8.1%) following SPDP without a significant difference (p=0.081). Portal vein thrombosis occurred in 4 patients after DP. Splenic infarction occurred in one patient after SPDP. Overwhelming postosplenectomy infection was observed in one patient after DP. SPDP can be achieved with no increase in complication rate, operative time, or length of postoperative hospitalization as compared to conventional DP. Additionally, it has the advantage of reducing the risk of overwhelming postsplenectomy infection and postoperative venous thrombosis. 相似文献
997.
Kee HJ Shin JH Chang J Chung KY Shin DH Kim YS Kim SK Kim SK 《Yonsei medical journal》2003,44(1):65-74
Small cell lung cancer (SCLC) frequently shows a loss of heterozygosity (LOH) on chromosome 15q. In order to define the commonly affected region on chromosome 15q, we tested 23 primary SCLCs by microsatellite analysis. By analyzing 43 polymorphic microsatellite markers located on chromosome 15q, we found that 14 (60.8%) of 23 tumors exhibited a LOH in at least one of the tested microsatellite markers. Two (14.3%) of the 14 tumors were found to have more than a 50% LOH on chromosome 15q. LOH was observed in five commonly deleted regions on 15q. Of those regions, LOH from D15S1012 to D15S1016 was the most frequent (47.8%). LOH was also observed in more than 20-30% of tumors at four other regions, from D15S1031 to D15S1007, from D15S643 to D15S980, from D15S979 to D15S202, and from D15S652 to D15S642. Four of the 23 tumors exhibited shifted bands in at least one of the tested microsatellite markers. Shifted bands occurred in 3.2% (29 of 914) of the loci tested. Our data suggests the presence of at least five tumor suppressor loci on chromosome 15q in SCLC, and further that these may play an important role in SCLC tumorigenesis. 相似文献
998.
Kim H Schuessler DG Bach CA Lin CC Nomeir AA 《Journal of chromatography. B, Biomedical sciences and applications》1999,735(1):11-16
SCH 66712 is a potent and selective dopamine D4 receptor antagonist. An HPLC method was developed for the analysis of SCH 66712 in the plasma of rats, a species used for safety evaluation of this compound. The method involved solid-phase extraction on an ethyl cartridge and HPLC separation on a reversed-phase C8 column with quantitation using a fluorescence detector. The calibration curve was linear over a concentration range of 5-100 ng/ml. The limit of quantitation was 5 ng/ml, where the coefficient of variation (C.V.) was 2.9% and the bias was 6%. The precision of the method was satisfactory as indicated by an intra-day C.V. of < or = 4% and an inter-day C.V. of < or = 6%. The accuracy was also satisfactory as shown by an intra-day bias of < or = 8% and an inter-day bias of < or = 9%. The assay was shown to be sensitive, specific, accurate, precise, and reliable for use in pharmacokinetic or toxicokinetic studies. 相似文献
999.
We report a 61-year-old right-handed man developing disturbance of memory after a discrete thalamic infarction. Neuropsychological assessment revealed deficits in memory with retrograde and anterograde components, especially for verbal material. Brain MRI showed a left anterior thalamic infarction with normal angiographic findings. Despite the small lesion in the thalamus, he showed prolonged memory disturbance and a Brain SPECT image revealed decreased uptake in the ipsilateral fronto-temporo-parietal cortex and contralateral cerebellum. This diaschisis, a phenomenon caused by disconnection of the neural pathway helped us to evaluate the functional state of the patient and this imaging technique was valuable for obtaining to get more information for the evaluation of the neurological state and neuronal connections. In conclusion our findings correspond well with the understanding of amnesia as a disconnection syndrome because of the evidence of diaschisis on the Brain SPECT image. 相似文献
1000.
Sheila G. Haworth Susan M. Hall Michael Chew Kim Allen 《Virchows Archiv : an international journal of pathology》1987,411(2):161-171
Summary Adaptation to extra-uterine life and postnatal remodelling of intra-acinar arteries was followed in 34 Large White pigs, from birth to adult life, applying morphometry to light and electronmicroscopic studies. After birth, percentage wall thickness decreased rapidly due to a reduction in overlap of adjacent smooth muscle cells and an increase in smooth muscle cell surface area/volume ratio, (p<0.01 at 12 h), without a reduction in the volume density of smooth muscle cells. Smooth muscle cells appeared immature at birth and synthetic rather than contractile organelles predominated. Between 3 weeks and 6 months myofilament volume density doubled (p< 0.0001). At all ages, pericytes, intermediate and smooth muscle cells showed similar volume densities of contractile and synthetic organelles. Thus, the high fetal pulmonary vascular resistance appeared to be due to the shape and arrangement of smooth muscle and other contractile cells within the vessel wall, rather than an excessive contractility of these cells. After birth rapid remodelling of arterial wall structure achieved a reduction in wall thickness by 30 min, continuing during the first week of life. After 3 weeks, remodelling involved an increase in wall thickness, connective tissue deposition with more collagen than elastin (p<0.0001), and smooth muscle cell differentiation. 相似文献