全文获取类型
收费全文 | 6129篇 |
免费 | 449篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 64篇 |
儿科学 | 207篇 |
妇产科学 | 118篇 |
基础医学 | 810篇 |
口腔科学 | 49篇 |
临床医学 | 981篇 |
内科学 | 1072篇 |
皮肤病学 | 80篇 |
神经病学 | 517篇 |
特种医学 | 140篇 |
外科学 | 683篇 |
综合类 | 49篇 |
一般理论 | 2篇 |
预防医学 | 771篇 |
眼科学 | 64篇 |
药学 | 419篇 |
中国医学 | 2篇 |
肿瘤学 | 569篇 |
出版年
2024年 | 9篇 |
2023年 | 68篇 |
2022年 | 99篇 |
2021年 | 234篇 |
2020年 | 122篇 |
2019年 | 171篇 |
2018年 | 190篇 |
2017年 | 137篇 |
2016年 | 141篇 |
2015年 | 169篇 |
2014年 | 213篇 |
2013年 | 314篇 |
2012年 | 478篇 |
2011年 | 480篇 |
2010年 | 235篇 |
2009年 | 262篇 |
2008年 | 367篇 |
2007年 | 426篇 |
2006年 | 400篇 |
2005年 | 416篇 |
2004年 | 348篇 |
2003年 | 346篇 |
2002年 | 297篇 |
2001年 | 54篇 |
2000年 | 35篇 |
1999年 | 49篇 |
1998年 | 58篇 |
1997年 | 39篇 |
1996年 | 51篇 |
1995年 | 49篇 |
1994年 | 35篇 |
1993年 | 43篇 |
1992年 | 16篇 |
1991年 | 14篇 |
1990年 | 14篇 |
1989年 | 14篇 |
1988年 | 15篇 |
1987年 | 10篇 |
1986年 | 13篇 |
1985年 | 9篇 |
1984年 | 32篇 |
1983年 | 19篇 |
1982年 | 16篇 |
1981年 | 16篇 |
1980年 | 10篇 |
1979年 | 11篇 |
1978年 | 5篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1974年 | 7篇 |
排序方式: 共有6597条查询结果,搜索用时 15 毫秒
121.
122.
Monitoring recovery from diaphragm paralysis with ultrasound 总被引:1,自引:0,他引:1
BACKGROUND: Diaphragmatic paralysis is an uncommon, yet underdiagnosed cause of dyspnea. Data regarding the time course and potential for recovery has come from a few small case series. The methods that have been traditionally employed to diagnose diaphragmatic weakness or paralysis are either invasive or limited in sensitivity and specificity. A new technique utilizing two-dimensional, B-mode ultrasound (US) measurements of diaphragm muscle thickening during inspiration (Deltatdi%) has been validated in the diagnosis of diaphragm paralysis (DP). The purpose of this study was to assess whether serial US evaluation might be utilized to monitor the potential recovery of diaphragm function. METHODS: Twenty-one consecutive patients with clinically suspected DP were referred to the pulmonary physiology laboratory. Sixteen patients were found to have DP by US (unilateral, 10 patients; bilateral, 6 patients). Subjects were followed up for up to 60 months. On initial and subsequent visits, Deltatdi% was measured by US. Additional measurements included upright and supine vital capacity (VC), maximal inspiratory pressure (Pimax), and maximal expiratory pressure. RESULTS: Eleven of 16 patients functionally recovered from DP. The mean (+/- SD) recovery time was 14.9 +/- 6.1 months. No diaphragm thickening was noted in those patients who did not recover. Positive correlations were found between improvement in Deltatdi% and interval changes in VC, Pimax, and end-expiratory measurements of diaphragm thickness. CONCLUSIONS: US may be used to assess for potential functional recovery from diaphragm weakness or DP. As in previous series, recovery occurs in a substantial number of individuals, but recovery time may be prolonged. 相似文献
123.
Albert Propst M.D. Theresa Propst M.D. Peter Waldenberger M.D. Wolfgang Vogel M.D. Gert Judmaier M.D. 《The American journal of gastroenterology》1995,90(8):1345-1346
Hepatoccllular adenomatosis is characterized by the presence of numerous (arbitrarily > 10) adenomas within an otherwise normal liver without a history of glycogen storage disease or steroid hormone therapy. Although the disease is rare, its importance lies in its tendency to produce symptoms such as abdominal pain and its potential for abdominal hemorrhages. However, the prognosis of hepatocellular adenomatosis remains uncertain. Here we describe the ease of a -40-yr-old female with hepatoccllular adenomatosis without evidence of serious complications, who was observed over a period of 11 yr. 相似文献
124.
Cytokinin/auxin balance in crown gall tumors is regulated by specific loci in the T-DNA 总被引:31,自引:7,他引:31
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Akiyoshi DE Morris RO Hinz R Mischke BS Kosuge T Garfinkel DJ Gordon MP Nester EW 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(2):407-411
Insertion of the transposon Tn5 into the T-region of the octopine Ti plasmid of Agrobacterium tumefaciens gives rise to crown gall tumors having altered morphology. Three loci within the T-DNA that control tumor morphology have been detected [Garfinkel, D. J., Simpson, R. B., Ream, L. W., White, F. F., Gordon, M. P. & Nester, E. W. (1981) Cell 27, 143-153]. They influence tumor size (tml), production of roots (tmr), or production of shoots (tms). Cytokinin and auxin levels in such mutant tumors were examined by HPLC/radioimmunoassay and HPLC/fluorescence assay, respectively. Free indoleacetic acid levels (in pmol/g) were: uninfected tobacco stem tissues, 128; wild-type A348 tumors, 295; tml mutant tumors, 307; tmr mutant tumors, 129; and tms mutant tumors, 70. Average trans-ribosylzeatin levels were correspondingly: 0.97, 48, 40, 0.54, and 1,400 pmol/g. trans-Ribosylzeatin/indoleacetic acid ratios were as high as 24 in shoot-producing tumors and as low as 0.003 in root-producing tumors. The evidence strongly suggests that tumor phytohormone levels are determined by genes in the T-DNA. 相似文献
125.
Brian D. Adkins Theresa A. Libby Marlene M. Mayberry Thomas W. Brady Justin B. Halls Stephanie Mallow Corbett Joseph Schoeny Eric P. Shields Jahan Chowdhury Amanda N. Kinsinger-Stickel Gay Wehrli Nicholas R. Jaeger Matthew P. Robertson Kathy M. Butler Stuart M. Lowson James Forrest Calland James D. Gorham 《Transfusion》2021,61(11):3066-3074
126.
Theresa Förg Christian T. Mayer Abdul Mannan Baru Catharina Arnold‐Schrauf Wendy W. J. Unger Hakan Kalay Yvette van Kooyk Tim Sparwasser 《European journal of immunology》2013,43(10):2543-2553
Vaccination is one of the oldest yet still most effective methods to prevent infectious diseases. However, eradication of intracellular pathogens and treatment of certain diseases like cancer requiring efficient cytotoxic immune responses remain a medical challenge. In mice, a successful approach to induce strong cytotoxic CD8+ T‐cell (CTL) reactions is to target antigens to DCs using specific antibodies against surface receptors in combination with adjuvants. A major drawback for translating this strategy into one for the clinic is the lack of analogous targets in human DCs. DC‐SIGN (DC‐specific‐ICAM3‐grabbing‐nonintegrin/CD209) is a C‐type lectin receptor with potent endocytic capacity and a highly restricted expression on human immature DCs. Therefore, DC‐SIGN represents an ideal candidate for DC targeting. Using transgenic mice that express human DC‐SIGN under the control of the murine CD11c promoter (hSIGN mice), we explored the efficacy of anti‐DC‐SIGN antibodies to target antigens to DCs and induce protective immune responses in vivo. We show that anti‐DC‐SIGN antibodies conjugated to OVA induced strong and persistent antigen‐specific CD4+ and CD8+ T‐cell responses, which efficiently protected from infection with OVA‐expressing Listeria monocytogenes. Thus, we propose DC targeting via DC‐SIGN as a promising strategy for novel vaccination protocols against intracellular pathogens. 相似文献
127.
Theresa Cole Fiona McKendrick Penny Titman Andrew J. Cant Mark S. Pearce Catherine M. Cale David Goldblatt Andrew R. Gennery 《Journal of clinical immunology》2013,33(1):8-13
Purpose
Chronic Granulomatous Disease (CGD) is a rare primary immunodeficiency that predisposes to life-threatening infections and inflammation. Haematopoietic stem cell transplant (HSCT) can cure CGD. Chronic illness reduces quality of life. Children with haematological malignancies report improved quality of life post-HSCT. There are no data for children with CGD. This study evaluated quality of life and emotional well-being in CGD children treated conventionally or transplanted.Methods
Parents and children completed the Pediatric Quality of Life Inventory v4.0 (PedsQL) and Strengths and Difficulties Questionnaires (SDQ). Mean scores were compared with published UK norms. Comparisons were made for those that had or had not undergone HSCT.Results
Forty-seven parents completed PedsQL (children aged 3–15). Twenty-one were post-HSCT. Forty-two completed SDQ (children aged 3–15). Nineteen post-HSCT. Median age for non-HSCT group 9 years. Median age for post-HSCT group 10 years. The HSCT group were median 3 years post-HSCT (range 1–9 years). HSCT survival was 90 %—two died without completing questionnaires Parent and self-reported quality of life for non-transplanted children was significantly lower than healthy children. Parents reported increased emotional difficulties compared to published norms. PedsQL and SDQ scores for transplanted children were not significantly different from healthy norms.Conclusions
This study demonstrates the quality of life is reduced in CGD. Transplanted patients have quality of life comparable to levels reported in healthy children. This data will help inform families and clinicians when deciding about treatment and may have relevance for other immunodeficiencies treated with transplant. 相似文献128.
Cost Katherine T. Zaidman-Zait Anat Mirenda Pat Duku Eric Zwaigenbaum Lonnie Smith Isabel M. Ungar Wendy J. Kerns Connor Bennett Theresa Szatmari Peter Georgiades Stelios Waddell Charlotte Elsabbagh Mayada Vaillancourt Tracy 《Journal of autism and developmental disorders》2021,51(12):4575-4576
Journal of Autism and Developmental Disorders - 相似文献
129.
Background
Ovarian cancer has a different prognosis between early (I and II) and advanced stage (III and IV). The mechanism of disease progression is unknown, but patients with advanced disease may have a higher propensity for seeding of the abdominal cavity early in the disease process than those with early stage. Theoretically if this is so, then patients with advanced stage should have smaller sized tumors than patients with early stage.Methods
This was a retrospective chart review of patients in the tumor registry in 2003–2006. Patients had epithelial ovarian cancer, other cell types were excluded. Only cases with documentation of surgical and pathologic staging and measured dimensions on pathologic specimen were included. Patient stage and all available dimensions measured on diseased ovaries were recorded. The dimensions for each patient were averaged into a single dimension for that patient, and then these measurements were totaled and averaged.Results
There were 110 patients analyzed: 85 with advanced disease, 25 with early stage. The average measurement was 4.8 cm in advanced disease, and was 10.7 cm in early stage disease. This difference was statistically significant (p < 0.001).Conclusions
Overall, patients with early stage ovarian cancer have diseased ovaries that are more than twice as large as those found in advanced disease. This finding supports the fact that early versus advanced ovarian cancer are 2 separate disease processes. Early stage grows locally and does not disseminate, and advanced stage disseminates while the tumor is still relatively small. Theoretically there may be a factor that separates these 2 into different diseases, where advanced disease patients have a substance produced by their tumor that allows for early dissemination, and early stage lacks this substance and only grows locally. Basic science research comparing the tissue microarrays of early versus advanced stage disease may be able to identify this difference. If the difference is found, perhaps therapy can be targeted against this difference, and screening tests for advanced ovarian cancer can be improved. 相似文献130.
Michael Zech MD Robert Jech MD PhD Sylvia Boesch MD Matej Škorvánek MD PhD Ján Necpál MD Jana Švantnerová MD Matias Wagner MD Ariane Sadr-Nabavi PhD Felix Distelmaier MD Martin Krenn MD PhD Tereza Serranová MD PhD Irena Rektorová MD PhD Petra Havránková MD PhD Alexandra Mosejová MD Iva Příhodová MD PhD Jana Šarláková MD Kristína Kulcsarová MD Olga Ulmanová MD PhD Karel Bechyně MD Miriam Ostrozovičová MD Vladimír Haň MD PhD Joaquim Ribeiro Ventosa MD Theresa Brunet MD Riccardo Berutti PhD Mohammad Shariati MD Ali Shoeibi MD Susanne A. Schneider MD Alice Kuster MD Matthias Baumann MD David Weise MD Friederike Wilbert MD Wibke G. Janzarik MD Matthias Eckenweiler MD Volker Mall MD Bernhard Haslinger MD Steffen Berweck MD Juliane Winkelmann MD Konrad Oexle MD 《Movement disorders》2021,36(8):1959-1964