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71.
Stable gene transfer and expression of human blood coagulation factor IX after intramuscular injection of recombinant adeno-associated virus 下载免费PDF全文
Roland W. Herzog J. Nathan Hagstrom Szu-Hoo Kung Shing Jen Tai James M. Wilson Krishna J. Fisher Katherine A. High 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(11):5804-5809
We sought to determine whether intramuscular injection of a recombinant adeno-associated virus (rAAV) vector expressing human factor IX (hF.IX) could direct expression of therapeutic levels of the transgene in experimental animals. High titer (1012–1013 vector genomes/ml) rAAV expressing hF.IX was prepared, purified, and injected into hindlimb muscles of C57BL/6 mice and Rag 1 mice. In the immunocompetent C57BL/6 mice, immunofluorescence staining of muscle harvested 3 months after injection demonstrated the presence of hF.IX protein, and PCR analysis of muscle DNA was positive for AAV DNA, but no hF.IX was detected in mouse plasma. Further studies showed that these mice had developed circulating antibodies to hF.IX. In follow-up experiments in Rag 1 mice, which carry a mutation in the recombinase activating gene-1 and thus lack functional B and T cells, similar results were seen on DNA analysis of muscle, but these mice also demonstrated therapeutic levels (200–350 ng/ml) of F.IX in the plasma. The time course of F.IX expression demonstrates that levels gradually increase over a period of several weeks before reaching a plateau that is stable 6 months after injection. In other experiments we demonstrate colocalization of hF.IX and collagen IV in intersitial spaces between muscle fibers. Collagen IV has recently been identified as a F.IX-binding protein; this finding explains the unusual pattern of immunofluorescent staining for F.IX shown in these experiments. Thus rAAV can be used to direct stable expression of therapeutic levels of F.IX after intramuscular injection and is a feasible strategy for treatment of patients with hemophilia B. 相似文献
72.
R Isfort D Jones R Kost R Witter H J Kung 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(3):991-995
Retroviruses and herpesviruses are naturally occurring pathogens of humans and animals. Coinfection of the same host with both these viruses is common. We report here that a retrovirus can integrate directly into a herpesvirus genome. Specifically, we demonstrate insertion of a nonacute retrovirus, reticuloendotheliosis virus (REV), into a herpesvirus, Marek disease virus (MDV). Both viruses are capable of inducing T lymphomas in chickens and often coexist in the same animal. REV DNA integration into MDV occurred in a recently attenuated strain of MDV and in a short-term coinfection experiment in vitro. We also provide suggestive evidence that REV has inserted into pathogenic strains of MDV in the past. Sequences homologous to the REV long terminal repeat are found in oncogenic MDV but not in nononcogenic strains. These results raise the possibility that retroviral information may be transmitted by herpesvirus and that herpesvirus expression can be modulated by retroviral elements. In addition, retrovirus may provide a useful tool to characterize herpesviral function by insertional mutagenesis. 相似文献
73.
Diversity and structure of human T-cell receptor beta-chain variable region genes. 总被引:23,自引:13,他引:23 下载免费PDF全文
P Concannon L A Pickering P Kung L Hood 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(17):6598-6602
The nucleotide sequences of 27 T-cell receptor beta cDNA clones isolated from a human peripheral lymphocyte library were determined and compared to five additional published sequences. These cDNA clones represent 22 distinct T-cell receptor beta-chain variable region (V beta) gene segment sequences, which fall into 15 different V beta gene subfamilies, each containing six or fewer members. From this analysis, we estimate that the repertoire of expressed human V beta genes is less than 59, apparently much smaller than the immunoglobulin heavy chain and light chain variable region (VH and VL) repertoires. Variability plots comparing these human V beta regions with each other and with published mouse V beta regions provide evidence for only four hypervariable regions homologous to those seen in comparisons of immunoglobulin V regions. Somatic hypermutation appears to be used infrequently, if at all, in these V beta genes. 相似文献
74.
N. Suciu-Foca E. Reed C. Rohowsky P. Kung D. W. King 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(3):830-834
We have previously shown that lymphoblasts alloactivated in vitro acquire the capacity of stimulating the autologous mixed lymphocyte response. This response is anti-idiotypic in nature because lymphocytes so primed display accelerated memory responses only when restimulated by autologous lymphoblasts that have been alloactivated against the same HLA-DR antigen. Based on this observation we have postulated that the absence of HLA antibodies in alloimmunized human subjects may be due to the development of autoantibodies that react with the anti-HLA receptors expressed by primed lymphocytes or by anti-HLA antibodies or both. This hypothesis has been confirmed in the present investigations which show that sera from parous women react with autologous T lymphoblasts primed in 5-day mixed lymphocyte culture against their husband—i.e., with lymphoblasts expressing receptors for the immunizing donor. Anti-HLA receptors expressed by T and B lymphocytes seem to share serologic determinants because sera that bind to autologous alloactivated lymphoblasts are also capable of inhibiting the anti-HLA activity of autologous and homologous sera. Auto-anti-idiotypic antibodies inhibit the autologous mixed lymphocyte response to autologous alloactivated lymphoblasts, a phenomenon whose in vivo correlate may reside in autoinhibition of anti-HLA antibody formation and of allograft immunity. Because auto-anti-idiotypic antibodies were found in sera from all parous women tested, the hypothesis that nonresponsiveness to alloantigens exists as a state per se is not likely. The passive transfer of antireceptor (idiotype) immunity by use of antibodies from pregnant women's sera may provide a powerful tool for specific suppression of allograft rejection. 相似文献
75.
Nicotinic Acid Metabolism, V. A Cobamide Coenzyme-Dependent Conversion of α-Methyleneglutaric Acid to Dimethylmaleic Acid 下载免费PDF全文
H. F. Kung S. Cederbaum L. Tsai T. C. Stadtman 《Proceedings of the National Academy of Sciences of the United States of America》1970,65(4):978-984
A new B(12)-coenzyme-dependent isomerization, catalyzed by extracts of a nicotinate-fermenting clostridium, results in the conversion of alpha-methyleneglutaric acid to dimethylmaleic acid. These two acids are intermediates in the multistep anaerobic process wherein nicotinate is converted, ultimately, to one mole each of propionate, acetate, carbon dioxide, and ammonia.Dimethylmaleic acid reacts in its anhydride form with 2,4-dinitrophenylhydrazine to form N-2',4'-dinitrophenyl-anilino-3,4-dimethylmaleimide. The characteristic reddish color exhibited by the latter derivative in alkaline solution serves as a convenient quantitative assay for dimethylmaleic acid. Comparison of the 2,4-dinitrophenylhydrazine derivatives of the product of the enzymic reaction and of synthetic dimethylmaleic anhydride showed them to be identical in every respect. 相似文献
76.
Shang-Jyh Chiou Pei-Tseng Kung James M. Naessens Kuang-Hua Huang Yu-Chia Chang Yueh-Hsin Wang Wen-Chen Tsai 《Diabetes research and clinical practice》2014
Aims
To assess whether the increased knowledge and resources available to physicians led to differences in dialysis and survival rates between physicians and non-physician patients with diabetes.Methods
All newly diagnosed (1997–2009) type 2 diabetes patients aged ≥35 years from the National Health Insurance Program of Taiwan database were included. After propensity score matching (1:10), we estimated the relative risk of dialysis and death using Cox proportional hazards model adjusted for demographic characteristics and comorbidities.Results
Physicians with diabetes were more likely to start dialysis than general patients, with a 48% increased hazard risk (HR) (P = 0.006). Physicians with diabetes had significantly lower risk of death (HR: 0.88; P = 0.025). However, those requiring dialysis had a non-significant increased risk of death (HR: 1.19). There was an increased HR for death in older physicians (HR: 1.81; P < 0.001) and those with cancer or catastrophic illness. The HR of dialysis (7.89; P < 0.0001) increased dramatically with increasing Charlson Comorbidity Index scores.Conclusions
Physicians with DM survived longer than other patients with diabetes, likely benefiting from their professional resources in disease control and prevention. Nonetheless, they displayed no advantage from their medical backgrounds compared with the general patients if they developed end stage renal disease. 相似文献77.
Xu Xiaoxia Zhu Hua Liu Fei Zhang Yan Yang Jianhua Zhang Lifang Xie Qing Zhu Lin Li Nan Kung Hank F. Yang Zhi 《European journal of nuclear medicine and molecular imaging》2020,47(10):2280-2292
European Journal of Nuclear Medicine and Molecular Imaging - The purpose of this study was to compare dynamic 18F-FGln PET/CT images of healthy subjects and cancer patients and explore the best... 相似文献
78.
A 9 year old girl presented with seizures, weight gain and early morning behavioural changes. She had been commenced on anticonvulsants and was subsequently diagnosed with hyperinsulinaemic hypoglycaemia. This case demonstrates the importance of blood glucose monitoring in children presenting with new‐onset seizures and/or with early morning or fasting behavioural changes, the challenges in localizing the lesion, as well as the difficulties in achieving normoglycaemia prior to, and immediately following, surgery. 相似文献
79.
Sen-Lin Xu Dong-Zu Zeng Wei-Guo Dong Yan-Qing Ding Jun Rao Jiang-Jie Duan Qing Liu Jing Yang Na Zhan Ying Liu Qi-Ping Hu Xia Zhang You-Hong Cui Hsiang-Fu Kung Shi-Cang Yu Xiu-Wu Bian 《International journal of clinical and experimental pathology》2014,7(6):2976-2986
Purpose: Aldehyde dehydrogenase 1A1 (ALDH1A1) has been proposed as a candidate biomarker for colorectal carcinoma (CRC). However, the heterogeneity of its expression makes it difficult to predict the outcome of CRC. The aim of this study was to evaluate the diagnostic and prognostic value of this molecule in CRC. Methods and Results: In this study, we examined ALDH1A1 expression by immunohistochemistry including 406 cases of primary CRC with corresponding adjacent mucosa, with confirmation of real-time PCR and Western blotting. We found that the expression patterns of ALDH1A1 were heterogeneous in the CRC and corresponding adjacent tissues. We defined the ratio of ALDH1A1 level in adjacent mucosa to that in tumor tissues as RA/C and found that the capabilities of tumor invasion and metastasis in the tumors with RA/C < 1 were significantly higher than those with RA/C ≥ 1. Follow-up data showed the worse prognoses in the CRC patients with RA/C < 1. For understanding the underlying mechanism, the localization of β-catenin was detected in the CRC tissues with different patterns of ALDH1A1 expression from 221 patients and β-catenin was found preferentially expressed in cell nuclei of the tumors with RA/C < 1 and ALDH1A1high expression of HT29 cell line, indicating that nuclear translocation of β-catenin might contribute to the increased potentials of invasion and metastasis. Conclusion: Our results indicate that RA/C is a novel biomarker to reflect the distinct expression patterns of ALDH1A1 for predicting metastasis and prognosis of CRC. 相似文献
80.
Pin-Yao Lin Fu-Jen Huang Fu-Tsai Kung Hsin-Ju Chiang Yu-Ju Lin Yi-Chi Lin Kuo-Chung Lan 《International journal of clinical and experimental pathology》2014,7(9):6245-6253
Objective: To determine whether or not the level of serum anti-Müllerian hormone (AMH) is related to early ovarian aging in young women (< 35 years of age) undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles. Design: Retrospective cohort study. Setting: An IVF laboratory in a university hospital in Taiwan. Patient (s): 70 young women (< 35 years of age) with low level of serum AMH (< 2 ng/ml) and 104 young women with level of serum AMH (≥ 2 ng/ml) who underwent IVF/ICSI cycles between January 2011 and November 2012 were enrolled. Intervention (s): None. Main outcome measure (s): Number of oocytes, fertilization rate, embryo quality, cycle cancellation rate, clinical pregnancy/abortion rate, and perinatal/infant outcomes. Results: The clinical pregnancy rate per transfer was favorable (low AMH group vs. normal AMH group [47.2% and 47.9%]) for women < 35 years of age, including women with a low serum AMH. Similarly, the live birth rate per transfer (low AMH group vs. normal AMH group [37.7% and 35.4%]) and perinatal outcomes were also comparable between the two groups. A significantly higher cycle cancellation was noted in the low AMH group than the normal AMH group (24.2% vs. 7.6%). Conclusion: Although early ovarian aging should be taken into consideration for young and infertile women with low AMH level than expected, our results suggest that low serum AMH level may suggest early ovarian aging in accelerated oocyte loss only, but may not fully represent “early ovarian aging” based on the favorable outcomes of pregnancy. 相似文献