全文获取类型
收费全文 | 10285篇 |
免费 | 904篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 58篇 |
儿科学 | 348篇 |
妇产科学 | 394篇 |
基础医学 | 1474篇 |
口腔科学 | 186篇 |
临床医学 | 1328篇 |
内科学 | 1996篇 |
皮肤病学 | 172篇 |
神经病学 | 1182篇 |
特种医学 | 269篇 |
外国民族医学 | 1篇 |
外科学 | 983篇 |
综合类 | 155篇 |
一般理论 | 8篇 |
预防医学 | 1028篇 |
眼科学 | 278篇 |
药学 | 527篇 |
1篇 | |
中国医学 | 41篇 |
肿瘤学 | 804篇 |
出版年
2023年 | 104篇 |
2022年 | 148篇 |
2021年 | 332篇 |
2020年 | 181篇 |
2019年 | 281篇 |
2018年 | 328篇 |
2017年 | 271篇 |
2016年 | 230篇 |
2015年 | 303篇 |
2014年 | 396篇 |
2013年 | 520篇 |
2012年 | 644篇 |
2011年 | 723篇 |
2010年 | 379篇 |
2009年 | 305篇 |
2008年 | 616篇 |
2007年 | 552篇 |
2006年 | 520篇 |
2005年 | 519篇 |
2004年 | 471篇 |
2003年 | 429篇 |
2002年 | 374篇 |
2001年 | 228篇 |
2000年 | 194篇 |
1999年 | 169篇 |
1998年 | 125篇 |
1997年 | 82篇 |
1996年 | 90篇 |
1995年 | 82篇 |
1994年 | 74篇 |
1993年 | 62篇 |
1992年 | 147篇 |
1991年 | 109篇 |
1990年 | 112篇 |
1989年 | 104篇 |
1988年 | 127篇 |
1987年 | 90篇 |
1986年 | 89篇 |
1985年 | 91篇 |
1984年 | 72篇 |
1983年 | 47篇 |
1982年 | 37篇 |
1981年 | 32篇 |
1980年 | 34篇 |
1979年 | 45篇 |
1978年 | 29篇 |
1977年 | 31篇 |
1974年 | 31篇 |
1973年 | 30篇 |
1969年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Estrogen and progesterone receptors have been measured in primary and secondary ovarian carcinoma in eight patients, in bilateral ovarian tumors in 16 patients, and from multiple sites within the same tumor in 16 patients (12 primary and 4 secondary). In the majority of cases, metastatic tumors contained less receptors than their primary tumors. Marked variations in receptor content were noted within the same tumor and between bilateral tumors. This variation in receptor levels may explain the discrepancy between the presence of receptors and the response to hormonal treatment. Multiple sites of ovarian carcinoma need to be assayed for receptor content before a final decision can be made on receptor status. 相似文献
92.
Improved design of nasogastric feeding tubes 总被引:1,自引:0,他引:1
Disappointed with the overall performance of weighted and unweighted nasogastric feeding tubes, a design programme was initiated which resulted in the development of two new nasogastric tubes, one weighted and one unweighted. The tubes were manufactured with polyurethane rather than polyvinylchloride (PVC) which permitted an increase in diameter of the internal lumen which in turn was coated with water activated lubricant to ease removal of the introducer wire. A specially modelled outflow port was incorporated into the tips of both tubes. The performance of the two new polyurethane nasogastric feeding tubes was assessed under controlled trial condition using as a reference a widely used PVC unweighted open ended tube. While intubation times were similar in patients without concurrent endotracheal intubation, it took a significantly shorter time to intubate patients with concurrent endotracheal intubation with the new weighted tube. Following tube intubation, it was possible to aspirate gastric contents significantly more often through the new polyurethane tubes (p < 0.001) than through the PVC tube, and the unweighted polyurethane tube stayed in situ longer (p < 0.05) than the PVC tube. The newly designed polyurethane nasogastric feeding tubes are the first tubes that have been shown to have advantages over the simpler type of open ended, unweighted PVC nasogastric feeding tubes. 相似文献
93.
Emilie Brard Christoph Rllig Sarah Bertoli Arnaud Pigneux Suzanne Tavitian Michael Kramer Hubert Serve Martin Bornhuser Uwe Platzbecker Carsten Müller-Tidow Claudia D. Baldus David Martínez-Cuadrn Josefina Serrano Pilar Martínez-Snchez Eduardo Rodríguez Arbolí Cristina Gil Juan Bergua Teresa Bernal Adolfo de la Fuente Burguera Eric Delabesse Audrey Bidet Pierre-Yves Dumas Pau Montesinos Christian Rcher 《Blood cancer journal》2022,12(7)
In a context of therapeutic revolution in older adults with AML, it is becoming increasingly important to select patients for the various treatment options by taking account of short-term efficacy and toxicity as well as long-term survival. Here, the data from three European registries for 1,199 AML patients aged 70 years or older treated with intensive chemotherapy were used to develop a prognostic scoring system. The median follow-up was 50.8 months. In the training set of 636 patients, age, performance status, secondary AML, leukocytosis, and cytogenetics, as well as NPM1 mutations (without FLT3-ITD), were all significantly associated with overall survival, albeit not to the same degree. These factors were used to develop a score that predicts long-term overall survival. Three risk-groups were identified: a lower, intermediate and higher-risk score with predicted 5-year overall survival (OS) probabilities of ≥12% (n = 283, 51%; median OS = 18 months), 3–12% (n = 226, 41%; median OS = 9 months) and <3% (n = 47, 8%; median OS = 3 months), respectively. This scoring system was also significantly associated with complete remission, early death and relapse-free survival; performed similarly in the external validation cohort (n = 563) and showed a lower false-positive rate than previously published scores. The European Scoring System ≥70, easy for routine calculation, predicts long-term survival in older AML patients considered for intensive chemotherapy.Subject terms: Acute myeloid leukaemia, Risk factors 相似文献
94.
High-throughput screening of a plant and marine invertebrate extract library to find natural products with rat thyrotropin releasing hormorne (TRH) receptor 2 binding affinity led to the isolation of four new (1-4) and one known (5) spongian diterpene from the sponge Spongia sp. The structures were assigned from interpretation of 2D NMR and high-resolution ESIMS data. The absolute configurations of 1-4 were proposed on the basis of analysis of their CD spectra. Diterpenes 1-5 showed rat TRH receptor 2 binding affinity with IC(50) values of 23 microM, 70 microM, 400 microM, 600 microM, and 1 mM, respectively. 相似文献
95.
96.
Treatment of cervical intraepithelial neoplasia (CIN) greatly reduces the risk of cervical cancer. Treatment involves ablation or excision of the transformation zone of the cervix, most commonly using an electrosurgical excision technique known as LLETZ. However, the peak incidence of CIN occurs in young women, so if excision of a portion of the cervix has an adverse effect on pregnancy outcome, this might have a significant impact. This review discusses the methodology and findings of the published literature on the association between cervical treatment and preterm birth, and the clinical implications of these findings. 相似文献
97.
Michael S. Gold Patrick J. Quinn Dianne E. Campbell Jane Peake Joanne Smart Marnie Robinson Michael OSullivan Josef Korbinian Vogt Helle Krogh Pedersen Xiaoqiu Liu Elham Pazirandeh-Micol Ralf G. Heine 《Nutrients》2022,14(11)
This open-label, non-randomized, multicenter trial (Registration: ) aimed to assess if an amino acid-based formula (AAF) supplemented with two human milk oligosaccharides (HMO) supports normal growth and is well tolerated in infants with a cow’s milk protein allergy (CMPA). Term infants aged 1–8 months with moderate-to-severe CMPA were enrolled. The study formula was an AAF supplemented with 2′-fucosyllactose (2′-FL) and lacto-N-neotetraose (LNnT). Infants were fed the study formula for 4 months and were offered to remain on the formula until 12 months of age. Tolerance and safety were assessed throughout the trial. Out of 32 infants (mean age 18.6 weeks; 20 (62.5%) male), 29 completed the trial. During the 4-month principal study period, the mean weight-for-age Z score (WAZ) increased from –0.31 at the baseline to +0.28 at the 4-months’ follow-up. Linear and head growth also progressed along the WHO child growth reference, with a similar small upward trend. The formula was well tolerated and had an excellent safety profile. When comparing the microbiome at the baseline to the subsequent visits, there was a significant on-treatment enrichment in HMO-utilizing bifidobacteria, which was associated with a significant increase in fecal short-chain fatty acids. In addition, we observed a significant reduction in the abundance of fecal Proteobacteria, suggesting that the HMO-supplemented study formula partially corrected the gut microbial dysbiosis in infants with CMPA. NCT 03661736相似文献
98.
Pragney Deme Leah H. Rubin Danyang Yu Yanxun Xu Gertrude Nakigozi Noeline Nakasujja Aggrey Anok Alice Kisakye Thomas C. Quinn Steven J. Reynolds Richard Mayanja James Batte Maria J. Wawer Ned C. Sacktor Deanna Saylor Norman J. Haughey 《Viruses》2022,14(6)
Background: HIV infection results in immunometabolic reprogramming. While we are beginning to understand how this metabolic reprogramming regulates the immune response to HIV infection, we do not currently understand the impact of ART on immunometabolism in people with HIV (PWH). Methods: Serum obtained from HIV-infected (n = 278) and geographically matched HIV seronegative control subjects (n = 300) from Rakai Uganda were used in this study. Serum was obtained before and ~2 years following the initiation of ART from HIV-infected individuals. We conducted metabolomics profiling of the serum and focused our analysis on metabolic substrates and pathways assocaited with immunometabolism. Results: HIV infection was associated with metabolic adaptations that implicated hyperactive glycolysis, enhanced formation of lactate, increased activity of the pentose phosphate pathway (PPP), decreased β-oxidation of long-chain fatty acids, increased utilization of medium-chain fatty acids, and enhanced amino acid catabolism. Following ART, serum levels of ketone bodies, carnitine, and amino acid metabolism were normalized, however glycolysis, PPP, lactate production, and β-oxidation of long-chain fatty acids remained abnormal. Conclusion: Our findings suggest that HIV infection is associated with an increased immunometabolic demand that is satisfied through the utilization of alternative energetic substrates, including fatty acids and amino acids. ART alone was insufficient to completely restore this metabolic reprogramming to HIV infection, suggesting that a sustained impairment of immunometabolism may contribute to chronic immune activation and comorbid conditions in virally suppressed PWH. 相似文献
99.
Meera Patel Kathryn A. F. Pennel Jean A. Quinn Hannah Hood David K. Chang Andrew V. Biankin Selma Rebus Antonia K. Roseweir James H. Park Paul G. Horgan Donald C. McMillan Joanne Edwards 《British journal of cancer》2022,126(12):1704
Background To understand the relationship between key non-canonical NF-κB kinase IKK-alpha(α), tumour mutational profile and survival in primary colorectal cancer.Methods Immunohistochemical expression of IKKα was assessed in a cohort of 1030 patients who had undergone surgery for colorectal cancer using immunohistochemistry. Mutational tumour profile was examined using a customised gene panel. Immunofluorescence was used to identify the cellular location of punctate IKKα expression.Results Two patterns of IKKα expression were observed; firstly, in the tumour cell cytoplasm and secondly as discrete ‘punctate’ areas in a juxtanuclear position. Although cytoplasmic expression of IKKα was not associated with survival, high ‘punctate’ IKKα expression was associated with significantly reduced cancer-specific survival on multivariate analysis. High punctate expression of IKKα was associated with mutations in KRAS and PDGFRA. Dual immunofluorescence suggested punctate IKKα expression was co-located with the Golgi apparatus.Conclusions These results suggest the spatial expression of IKKα is a potential biomarker in colorectal cancer. This is associated with a differential mutational profile highlighting possible distinct signalling roles for IKKα in the context of colorectal cancer as well as potential implications for future treatment strategies using IKKα inhibitors.Subject terms: Prognostic markers, Colorectal cancer 相似文献
100.