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61.
Reduced blood BDCA-2+ (lymphoid) and CD11c+ (myeloid) dendritic cells in systemic lupus erythematosus 总被引:1,自引:0,他引:1 下载免费PDF全文
Migita K Miyashita T Maeda Y Kimura H Nakamura M Yatsuhashi H Ishibashi H Eguchi K 《Clinical and experimental immunology》2005,142(1):84-91
Type 1 IFN is thought to be implicated in the autoimmune process of SLE. Plasmacytoid dendric cells (DC), which are natural IFN-alpha producing cells, play a pivotal epipathogenic role in SLE. The present study was undertaken to investigate the phenotypic characteristics of peripheral blood DC in SLE patients in comparison with those of healthy controls. Samples from 20 SLE patients and 18 healthy controls were studied. Three-colour flow cytometry was performed to identify myeloid DC, as CD11c(+) lineage marker(-), and HLA-DR(+) cells and plasmacytoid DC, as BDCA-2(+) linage marker(-), and HLA-DR(+) cells. We used the whole blood 'lyse/no-wash' procedure, which allows precise counting of peripheral blood DC. BDCA-2(+) plasmacytoid DC and CD11c(+) myeloid DC were reduced in SLE patients compared with controls. Similarly, BDCA-3(+) DC were reduced in SLE patients. These results indicated that SLE patients had a reduced number of both BDCA-2(+) plasmacytoid DC and CD11c(+) myeloid DC. These alternations of the DC subset may drive the autoimmune response in SLE. 相似文献
62.
Isolation of amantadine-resistant influenza a viruses (H3N2) from patients following administration of amantadine in Japan 总被引:3,自引:0,他引:3 下载免费PDF全文
Iwahashi J Tsuji K Ishibashi T Kajiwara J Imamura Y Mori R Hara K Kashiwagi T Ohtsu Y Hamada N Maeda H Toyoda M Toyoda T 《Journal of clinical microbiology》2001,39(4):1652-1653
In Japan, the use of amantadine for treatment of influenza A virus infection was not accepted until November 1998, although it was widely used for treatment of Parkinsonism. Since then, we have monitored the emergence of amantadine-resistant viruses and isolated two viruses from patients on long-term treatment with amantadine. 相似文献
63.
Developmental switch from GABA to glycine release in single central synaptic terminals 总被引:8,自引:0,他引:8
Nabekura J Katsurabayashi S Kakazu Y Shibata S Matsubara A Jinno S Mizoguchi Y Sasaki A Ishibashi H 《Nature neuroscience》2004,7(1):17-23
Early in postnatal development, inhibitory inputs to rat lateral superior olive (LSO) neurons change from releasing predominantly GABA to releasing predominantly glycine into the synapse. Here we show that spontaneous miniature inhibitory postsynaptic currents (mIPSCs) also change from GABAergic to glycinergic over the first two postnatal weeks. Many 'mixed' mIPSCs, resulting from co-release of glycine and GABA from the same vesicles, are seen during this transition. Immunohistochemistry showed that a large number of terminals contained both GABA and glycine at postnatal day 8 (P8). By P14, both the content of GABA in these mixed terminals and the contribution of GABA to the mixed mIPSCs had decreased. The content of glycine in terminals increased over the same period. Our results indicate that switching from GABAergic to glycinergic inputs to the LSO may occur at the level of a single presynaptic terminal. This demonstrates a new form of developmental plasticity at the level of a single central synapse. 相似文献
64.
Immunohistochemical analysis of centromere protein F expression in buccal and gingival squamous cell carcinoma 总被引:4,自引:0,他引:4
Centromere protein F (CENP-F) expression (localization and characteristics) in relation to tumor clinicopathological parameters was immunohistochemically examined and evaluated in 47 archival biopsy specimens of buccal and gingival squamous cell carcinomas (SCC). Centromere protein F expression was detected in 79% of the samples. An increase in the labeling index (LI) with WHO grading was obtained ( P < 0.05). Correlations were obtained between the CENP-F LI and tumor size ( P < 0.05). Immunoelectron microscopy showed CENP-F nuclear staining as punctate or fine dots. The present study shows that CENP-F expression and detection of a more specific cell subpopulation presents a theoretical advantage for the analysis of the precise cell cycle of G2 to M cells, compared to Ki-67. 相似文献
65.
Shigemitsu Iwai MD Kei Torikai MD Chris M. Coppin MD Yoshiki Sawa MD 《Journal of artificial organs》2007,10(1):29-35
Currently used bioprosthetic valves have several limitations such as calcification and functional deterioration, and revitalization
through cellular ingrowth is impossible. To overcome these obstacles, we have developed a minimally immunogenic tissue-engineered
valve that consists of an unfixed, decellularized porcine valve scaffold capable of being spontaneously revitalized in vivo
after implantation. Porcine aortic root tissue was decellularized using detergents such as sodium lauryl sulfate and Triton
X-100. The porcine valve was treated very gently and plenty of time was allowed for constituents to diffuse in and out of
the matrix. In a preliminary study, a piece of decellularized porcine valve tissue was implanted into the rat subdermal space
for 14 and 60 days and the structural integrity and calcification were evaluated. As an in vivo valve replacement model, the
decellularized porcine valve was implanted in the pulmonary valve position in dogs and functional and histological evaluation
was performed after 1, 2, and 6 months. Histological examination showed that the newly developed detergent treatment effectively
removed cellular debris from the porcine aortic tissue. Decellularized porcine valve tissue implanted subdermally in rats
showed minimal inflammatory cell infiltration and calcification. In the valve replacement model, spontaneous reendothelialization
and repopulation of the medial cells were observed within 2 months, and good valve function without regurgitation was observed
by echocardiography up to 6 months. The minimally immunogenic decellularized porcine valve proved effective in mitigating
postimplant calcification and provided a suitable matrix for revitalizing prostheses through in situ recellularization, cellular
ingrowth, and tissue remodeling. 相似文献
66.
Biological properties and gene expression associated with metastatic potential of human osteosarcoma 总被引:4,自引:0,他引:4
Nakano T Tani M Ishibashi Y Kimura K Park YB Imaizumi N Tsuda H Aoyagi K Sasaki H Ohwada S Yokota J 《Clinical & experimental metastasis》2003,20(7):665-674
Lung metastasis has a great influence on the prognosis of patients with osteosarcoma. We previously established two high-metastatic
sublines, M112 and M132, from the HuO9 human osteosarcoma cell line by in vivo selection. In this study, we newly isolated a high-metastatic subline, H3, and three low-metastatic sublines, L6, L12 and
L13, from HuO9 by the dilution plating method. Three high-metastatic sublines produced more than 200 metastatic nodules in
the lung, while three low-metastatic sublines produced no or few nodules after injection of 2 × 106 cells into the tail vein of nude mice. There were significant differences in the motility and invasiveness between high-
and low-metastatic sublines, whereas the growth rates in vitro and the tumorigenicity in vivo showed no correlation with their metastatic abilities. Early adherence to culture plates was significantly lower in two of
three low-metastatic sublines, which occupied smaller surface areas on the culture plates than other sublines did. Comparison
of the expression of 637 cancer-related genes by cDNA microarray revealed that seven genes were differentially expressed between
high- and low-metastatic sublines. Among them, five genes (AXL, TGFA, COLL7A1, WNT5A, and MKK6) were associated with adherence, motility, and/or invasiveness. These results suggest that the differences in motility/invasiveness
and adhesive abilities are key determinants of lung metastasis in osteosarcoma.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
67.
Bordetella pertussis, the agent of whooping cough, is capable of invading human respiratory epithelial cells. In this study, we investigated the mechanisms by which B. pertussis invades the human lung epithelial cell line A549 and normal human bronchial epithelial (NHBE) cells. In vitro adhesion and invasion assays using both cell types with a virulent B. pertussis strain and its isogenic mutants revealed profound defects in a mutant deficient in filamentous hemagglutinin (FHA) expression. In addition, a mutant in which an FHA Arg-Gly-Asp (RGD) site had been changed to Arg-Ala-Asp had significantly diminished invasiveness, although its adhesiveness was comparable to that of the parental strain. Furthermore, a synthetic RGD-containing hexapeptide inhibited invasion of both cell types by the virulent strain. These results demonstrate that an RGD sequence of FHA is involved in B. pertussis invasion of epithelial cells in vitro. Monoclonal antibodies directed against human alpha5beta1 integrin, but not other integrins, blocked invasion, indicating that this integrin is involved in B. pertussis invasion. Taken together, these findings suggest that B. pertussis FHA may promote invasion of human respiratory epithelial cells through the interaction of its RGD sequence with host cell alpha5beta1 integrin. 相似文献
68.
Masaki Iwai Yasutaka Ishu Yoshihiro Kitagawa Kazunobu Tada Motomu Kashiwadani Takeshi Okanoue Kei Kashima 《Medical molecular morphology》1993,26(3-4):207-210
The immunoreactivity of albumin (ALB) was observed in the hepatocytes of fetal rats on day 18 of gestation, and was especially observable in immature rough endoplasmic reticulum (rER) and Golgi apparatus (GA); by then, a small amount of silver grains of ALB mRNA could already be detected. Just after birth, immunoreactivity of ALB could be observed in fine granules or diffusely in all hepatocytes, and was present in rER and GA. One week after birth immunoreactivity of ALB was observed in all hepatocytes and was visible in developed rER and GA; the grains of ALB mRNA were present in all hepatocytes. 相似文献
69.
Y Akiyama T Suzuki M Tanaka K Kobayashi T Kagiri T Ishibashi H Kitagawa F Imai K Hara Y Doi 《Arerugī》1990,39(6):542-547
We encountered a patient who developed an overlap syndrome of progressive systemic sclerosis (PSS), systemic lupus erythematosus (SLE), polymyositis (PM) and Sj?gren's syndrome (SjS) while we were treating her for mixed connective tissue disease (MCTD). This 42-year-old woman had been photosensitive since 18 years of age. In 1986, Raynaud's phenomenon, swollen hands and arthralgia appeared; therefore, we started to treat this patient based on a diagnosis of MCTD. At that time, her anti-RNP antibody titer was 82,920, but she was negative to anti-Sm antibody. In 1988, she was admitted to our hospital with chief complaints of aggravation of polyarthralgia and myalgia. On physical examination, she showed difficulty in opening her mouth, systemic dermal sclerosis, a decrease in muscular strength and rales. In laboratory tests, her myogenic enzyme level was increased, and she was found to be positive to LE cells, antinuclear antibody, anti-DNA antibody, anti-ENA antibody and anti-SSA antibody. Furthermore, histological features clearly corresponding to those of PSS were found by skin biopsy, myogenic changes by electromyography, evidence of chronic inflammation of the salivary glands by lip biopsy, and proliferative changes in the mesangium were detected by renal biopsy. The concept of MCTD, especially the differences from overlap syndrome, is vague. Therefore we need further study about many cases. Since there have been no reports on cases having sufficient evidence of the development of the overlap syndrome of PSS, SLE, PM and SjS during a course of MCTD, our patient would provide very useful data contributing to the study of MCTD. 相似文献
70.