全文获取类型
收费全文 | 4203篇 |
免费 | 205篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 30篇 |
儿科学 | 173篇 |
妇产科学 | 82篇 |
基础医学 | 599篇 |
口腔科学 | 88篇 |
临床医学 | 424篇 |
内科学 | 822篇 |
皮肤病学 | 67篇 |
神经病学 | 412篇 |
特种医学 | 198篇 |
外国民族医学 | 1篇 |
外科学 | 696篇 |
综合类 | 19篇 |
预防医学 | 224篇 |
眼科学 | 66篇 |
药学 | 251篇 |
中国医学 | 6篇 |
肿瘤学 | 280篇 |
出版年
2023年 | 25篇 |
2022年 | 31篇 |
2021年 | 79篇 |
2020年 | 46篇 |
2019年 | 52篇 |
2018年 | 71篇 |
2017年 | 47篇 |
2016年 | 85篇 |
2015年 | 85篇 |
2014年 | 108篇 |
2013年 | 156篇 |
2012年 | 214篇 |
2011年 | 291篇 |
2010年 | 152篇 |
2009年 | 153篇 |
2008年 | 249篇 |
2007年 | 226篇 |
2006年 | 212篇 |
2005年 | 228篇 |
2004年 | 168篇 |
2003年 | 188篇 |
2002年 | 170篇 |
2001年 | 117篇 |
2000年 | 108篇 |
1999年 | 111篇 |
1998年 | 51篇 |
1997年 | 48篇 |
1996年 | 37篇 |
1995年 | 33篇 |
1994年 | 37篇 |
1993年 | 19篇 |
1992年 | 66篇 |
1991年 | 48篇 |
1990年 | 54篇 |
1989年 | 41篇 |
1988年 | 46篇 |
1987年 | 38篇 |
1986年 | 33篇 |
1985年 | 37篇 |
1984年 | 40篇 |
1983年 | 23篇 |
1981年 | 18篇 |
1979年 | 33篇 |
1978年 | 18篇 |
1973年 | 21篇 |
1972年 | 20篇 |
1971年 | 18篇 |
1970年 | 19篇 |
1967年 | 16篇 |
1966年 | 17篇 |
排序方式: 共有4438条查询结果,搜索用时 343 毫秒
51.
Die Anaesthesiologie - Die Immunthrombozytopenie (ITP) ist eine seltene, erworbene Thrombozytopenie mit einer Inzidenz von 2–4/100.000 Personen und Jahr. Sie wird durch eine Thrombozytenzahl... 相似文献
52.
Hanno Niess Nikolaus Börner Maximilian Muenchhoff Elham Khatamzas Manfred Stangl Alex Graf Philipp Girl Enrico Georgi Dionysios Koliogiannis Gerald Denk Michael Irlbeck Jens Werner Markus Guba 《American journal of transplantation》2021,21(4):1629-1632
To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA. 相似文献
53.
Craniofacial development, one of the most complex sequences of developmental events in embryology, features a uniquely transient, pluripotent stem cell-like population known as the neural crest (NC). Neural crest cells (NCCs) originate from the dorsal aspect of the neural tube and migrate along pre-determined routes into the developing branchial arches and frontonasal plate. The exceptional rates of proliferation and migration of NCCs enable their diverse contribution to a wide variety of craniofacial structures. Subsequent differentiation of these cells gives rise to cartilage, bones, and a number of mesenchymally-derived tissues. Deficiencies in any stage of differentiation can result in facial clefts and abnormalities associated with craniofacial syndromes. A small number of conserved signaling pathways are involved in controlling NC differentiation and craniofacial development. They are used in a reiterated fashion to help define precise temporospatial cell and tissue formation. Although many aspects of their cellular and molecular control have yet to be described, it is clear that together they form intricately integrated signaling networks required for spatial orientation and developmental stability and plasticity, which are hallmarks of craniofacial development. Mutations that affect the functions of these signaling pathways are often directly or indirectly identified in congenital syndromes. Clinical applications of NC-derived mesenchymal stem/progenitor cells, persistent into adulthood, hold great promise for tissue repair and regeneration. Realization of NCC potential for regenerative therapies motivates understanding of the intricacies of cell communication and differentiation that underlie the complexities of NC-derived tissues. 相似文献
54.
55.
The gene that encodes the membrane-bound Mr 100,000 human melanoma-associated antigen (MAA) defined by mouse mAb 376.96, a leukocyte and fibroblast interferon-modulated glycoprotein having preferential distribution on melanoma and carcinoma cells, has been transfected into the mouse melanoma cell line B78H1 as a step toward molecular cloning and characterization of the MAA. Primary, secondary, and tertiary B78H1 transfectants expressing the Mr 100,000 MAA gene were generated by treatment with coprecipitated DNA from Mr 100,000 MAA+ human or transfectant mouse cells and they were detected by an indirect RBC rosetting assay. The Mr 100,000 MAA gene was also transferred into K-1735 mouse melanoma cells and into nonmalignant and malignant mouse fibroblast lines. The species immunoprecipitated by mAb 376.96 from human melanoma cells (Mr 100,000) and from mouse melanoma transfectant cells (Mr 97,000-100,000) were both converted to molecule(s) having an Mr of approximately 70,000 by enzymatic removal of asparagine-linked carbohydrate residues. Two independent secondary transformant clones of B78H1 cells express Mr 100,000 MAA antigenicity at levels significantly higher than those observed when one or two copies of the gene are present. Clone Mr 100,000 secondary-A spontaneously overexpresses Mr 100,000 MAA at least 5-fold and has greater than or equal to 10 times elevated levels of putatively Mr 100,000 MAA gene-associated human alu family repeat element (h-alu)-positive restriction fragments relative to "single" copy secondary transfectant cells. Clone Mr 100,000 secondary-B has increased copy number and expression of Mr 100,000 MAA as a consequence of a selective co-amplification procedure which is targeted to a mouse wild type dihydrofolate reductase (dhfr) gene expression vector. This vector was co-introduced into B78H1 cells in addition to the DNA of Mr 100,000 MAA+ primary transfectant cells and the initially selected aminoglycoside phosphotransferase (neo) gene vector. Stepwise selections of a secondary Mr 100,000 MAA+ transfectant clone with increasing concentrations of the dihydrofolate reductase-inhibitory antimetabolite methotrexate led to progressive increases in copy numbers of the introduced dhfr gene and to parallel increases in h-alu sequences, in cellular levels of dihydrofolate reductase protein, and in cellular mAb 376.96 reactivity. Levels of these entities ultimately reached 50-fold, relative to levels expressed prior to amplification. The array of h-alu+ restriction fragments amplified in Mr 100,000 secondary-B cell DNA is very similar to that observed in Mr 100,000 secondary-A cell DNA.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
56.
The constitutional gain-of-function variant p.Glu1099Lys in NSD2 is associated with a novel syndrome
Bernt Popp Melanie Brugger Sibylle Poschmann Tobias Bartolomaeus Maximilian Radtke Julia Hentschel Nataliya Di Donato Andreas Rump Janina Gburek-Augustat Elisabeth Graf Matias Wagner Ina Sorge Johannes R Lemke Thomas Meitinger Rami Abou Jamra Vincent Strehlow Theresa Brunet 《Clinical genetics》2023,103(2):226-230
57.
Mapelli V Graf vond der Schulenburg JM Laaser U Allhoff PG Rossi F 《PharmacoEconomics》1994,6(Z2):27-35
Data from a French placebo-controlled double-blind trial in 120 female patients treated with high dose fluorouracil, epirubicin and cyclophosphamide (HD-FEC) chemotherapy for inflammatory breast cancer were used to assess the economic impact of adjunctive lenograstim therapy. The analysis compared direct costs of treatment, with or without lenograstim, with reference to the Social Security (Germany) or to the National Health Service (Italy). Resource utilisation differed between the 2 treatment groups. The lenograstim group reported 32% fewer antibiotic therapy days (9.8 days vs 14.6; p = 0.01) and 24% fewer inpatient days for any reason other than chemotherapy (7.4 'excess' days vs 9.8). By reducing infection-related morbidity associated with a high dose chemotherapy regimen, lenograstim decreased treatment costs by DM 1794 and ItL 1.2 million, excluding the cost of lenograstim itself. Since lenograstim patients reported fewer chemotherapy delays (16.4 vs 30.5%) and, hence, benefited from 1.2 (p = 0.04) more chemotherapy days, the related cost was DM 1519 and ItL 0.9 million higher than for the placebo group. This cost difference would be expected to be smaller if the placebo group patients had been followed until completion of their full chemotherapy regimen. Assuming that the costs of chemotherapy were the same for both groups, the direct cost saving for the lenograstim group would be 30% in Germany and 34% in Italy. 相似文献
58.
Rosen A Reiner A Klein M Lahousen M Graf A Vavra N Auerbach L Rosen H 《Oncology reports》1994,1(4):853-856
A retrospective evaluation of 68 Fallopian tube carcinomas (FTC) of a period of ten years (1980-1990) in stage I and II was performed. The aim of this study was to evaluate the prognostic impact of various factors. 68 cases were investigated for the prognostic influence of mitotic activity, degree of nuclear anaplasia and inflammatory reaction. Histological grading (p=0.08), and inflammatory reaction (p=0.003) showed to have a prognostic impact for survival in univariate analysis. Whereas, mitotic activity did not show any statistically significant influence. 47 (69%) tissue samples showed a positive inflammatory reaction which correlated with a significantly better outcome compared with tumors without this feature. However, this influence was proved in multivariate analysis for inflammatory reaction only (p=0.01). Although no data on the influence of the inflammatory reaction on prognosis in FTC has been published up to now, we can state that the determination of this factor can be useful for prognosis in this rare but highly aggressive tumor. 相似文献
59.
A placebo-controlled trial of lamotrigine add-on therapy for partial seizures in children. Lamictal Pediatric Partial Seizure Study Group 总被引:6,自引:0,他引:6
Duchowny M Pellock JM Graf WD Billard C Gilman J Casale E Womble G Risner M Manasco P 《Neurology》1999,53(8):1724-1731
OBJECTIVE: To compare the safety and efficacy of add-on lamotrigine and placebo in the treatment of children and adolescents with partial seizures. BACKGROUND: Add-on and monotherapy lamotrigine is safe and effective in adults with partial seizures, and reports of preliminary uncontrolled trials suggest similar benefits in children. METHODS: We studied 201 children with diagnoses of partial seizures of any subtype currently receiving stable conventional regimens of antiepileptic therapy at 40 study sites in the United States and France. After a baseline observation period (to confirm that more than four seizures occurred in each of two consecutive 4-week periods), patients were randomized to add-on lamotrigine or placebo therapy. A 6-week dose-escalation period was followed by a 12-week maintenance period. RESULTS: Compared with placebo, lamotrigine significantly reduced the frequency of all partial seizures and the frequency of secondarily generalized partial seizures in these treatment-resistant patients. The most commonly reported adverse events in the lamotrigine-treated patients were vomiting, somnolence, and infection; the frequency of these and other adverse events was similar to that in the placebo-treated group, with the exception of ataxia, dizziness, tremor, and nausea, which were more frequent in the lamotrigine-treated group. The frequency of withdrawals for adverse events was similar between groups. Two patients were hospitalized for skin rash, which resolved after discontinuation of lamotrigine therapy. CONCLUSIONS: Lamotrigine was effective for the adjunctive treatment of partial seizures in children and demonstrated an acceptable safety profile. 相似文献
60.
The Ultrapulse CO2 laser (Coherent Inc., Palo Alto, CA, USA) was used in 239 patients, from March 1996 to July 1998, for full-face laser resurfacing.
In 106 (43%) of these patients rhytidectomy was performed in the same procedure. All patients submitted to laser resurfacing
were prepared for 1 to 2 months beforehand with retinoic acid and hydroquinone. The procedures were done under local anesthesia
controlled by an anesthesiologist. A clear film dressing impregnated with silicone gel (Silon TSR; Bio-Med Sciences, Bethlehem,
PA, USA) was used for 6 to 7 days and complete healing was observed in 7 to 10 days. Complications were exclusively dermatologic,
without relation to surgery. No necrosis of the cutaneous flap was observed. Skin biopsies of 10 consecutive patients undergoing
the combined procedures revealed no vascular impairment to the dermis. The patients were able to resume their activities 2
weeks after the procedure. 相似文献