全文获取类型
收费全文 | 9381篇 |
免费 | 740篇 |
国内免费 | 29篇 |
专业分类
耳鼻咽喉 | 56篇 |
儿科学 | 410篇 |
妇产科学 | 242篇 |
基础医学 | 1336篇 |
口腔科学 | 189篇 |
临床医学 | 1167篇 |
内科学 | 1780篇 |
皮肤病学 | 88篇 |
神经病学 | 1123篇 |
特种医学 | 170篇 |
外科学 | 733篇 |
综合类 | 106篇 |
一般理论 | 11篇 |
预防医学 | 1404篇 |
眼科学 | 126篇 |
药学 | 432篇 |
中国医学 | 29篇 |
肿瘤学 | 748篇 |
出版年
2023年 | 51篇 |
2022年 | 98篇 |
2021年 | 227篇 |
2020年 | 134篇 |
2019年 | 222篇 |
2018年 | 251篇 |
2017年 | 180篇 |
2016年 | 201篇 |
2015年 | 213篇 |
2014年 | 296篇 |
2013年 | 440篇 |
2012年 | 620篇 |
2011年 | 676篇 |
2010年 | 377篇 |
2009年 | 326篇 |
2008年 | 676篇 |
2007年 | 658篇 |
2006年 | 656篇 |
2005年 | 655篇 |
2004年 | 609篇 |
2003年 | 563篇 |
2002年 | 530篇 |
2001年 | 52篇 |
2000年 | 45篇 |
1999年 | 85篇 |
1998年 | 112篇 |
1997年 | 88篇 |
1996年 | 81篇 |
1995年 | 87篇 |
1994年 | 63篇 |
1993年 | 52篇 |
1992年 | 40篇 |
1991年 | 37篇 |
1990年 | 33篇 |
1989年 | 44篇 |
1988年 | 30篇 |
1987年 | 34篇 |
1986年 | 27篇 |
1985年 | 34篇 |
1984年 | 29篇 |
1983年 | 49篇 |
1982年 | 56篇 |
1981年 | 47篇 |
1980年 | 40篇 |
1979年 | 12篇 |
1978年 | 26篇 |
1977年 | 19篇 |
1976年 | 17篇 |
1974年 | 12篇 |
1972年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Mark S. Wallace Steven G. Charapata Robert Fisher Michael Byas‐Smith Peter S. Staats Martha Mayo Dawn McGuire David Ellis 《Neuromodulation》2006,9(2):75-86
Objective. The safety and efficacy of intrathecal (IT) ziconotide was studied in a randomized, double‐blind, placebo‐controlled trial. Materials and Methods. Patients (169 ziconotide, 86 placebo) with severe chronic nonmalignant pain unresponsive to conventional therapy and a visual analog scale of pain intensity (VASPI score) ≥ 50 mm were treated over a 6‐day period in an inpatient hospital setting. Initial starting dose was 0.4 µg/hour and was titrated to analgesia or intolerance (maximum dose 7.0 µg/hour). The starting and maximum doses were reduced to 0.1 µg/hour and 2.4 µg/hour, respectively, due to adverse events (AEs). Results. The mean percent reduction in VASPI score from baseline was 31.2% and 6.0% for ziconotide‐ and placebo‐treated patients, respectively (p ≤ 0.001). During the initial titration phase, a significantly greater percentage of patients in the ziconotide group compared to the placebo group reported AEs, including abnormal gait, amblyopia, dizziness, nausea, nystagmus, pain, urinary retention, and vomiting. Conclusion. Ziconotide provided significant analgesia in patients for whom conventional therapy failed. However, there was a considerable incidence of ziconotide‐associated AEs due to the rapid titration and high doses administered. 相似文献
6.
Rammurti T Kamble George B Selby Martha Mims Mohamed A Kharfan-Dabaja Howard Ozer James N George 《Biology of blood and marrow transplantation》2006,12(5):506-510
Iron overload presenting as exacerbation of hepatic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation has not been previously described. We report 6 patients with established hepatic GVHD in whom iron overload (median serum ferritin, 7231 mug/dL; median transferrin saturation, 77%) resulting from a lifetime median of 20 units of packed red blood cell transfusions was manifested by worsening of liver function. Liver biopsies performed in 4 patients confirmed severe iron overload and also hepatic GVHD. Analysis for the C282Y and H63D hemochromatosis gene mutation was negative for the homozygous state in all 6 patients. Erythropoietin-assisted phlebotomy resulted in normalization of liver function at a median of 7 months and of serum ferritin at a median of 11 months. Immunosuppressive therapy was successfully tapered in all 4 patients who completed the phlebotomy program, and this supported the impression that iron overload, rather than GVHD, was the principal cause of liver dysfunction. At a median follow-up of 50 months (range, 18-76 months) from the transplantation and 25 months (range, 5-36 months) from ferritin normalization, all 4 patients require maintenance phlebotomy. We conclude that iron overload can mimic GVHD exacerbation, thus resulting in unnecessary continuation or intensification of immunosuppressive therapy for GVHD, and that maintenance phlebotomy is necessary after successful iron-reduction therapy. 相似文献
7.
Performance characteristics of pooled rabbit IgG polyclonal anti-C3d are compared with one mouse IgM and three mouse IgG monoclonal anti-C3d antibodies (MAs). IgG MA,s employed singly or in combination, failed to precipitate C3d; by contrast, IgM MA and polyclonal anti-C3d precipitated C3d. Measurements of polyclonal anti-C3d concentration by chemical means and by 125I-C3d radioimmunoassay (RIA) agreed closely. RIA values were 50% of chemical measurement values for three of the four MAs. Use of sucrose density gradient ultracentrifugation to assess MA C3d/anti-C3d molar combining ratios for soluble anti-C3d/C3d was not possible because fast-sedimenting multimeric C3d/anti-C3d complexes did not form. Dissociation and competitive binding studies indicate that (1) two MAs had substantially lower affinities than the other anti-C3d antibodies, and (2) polyclonal anti-C3d recognizes more C3d epitopes than are recognized by individual MAs. The results demonstrate antigenic complexity of C3d fragment and illustrate the difficulties of predicting individual MA performance based on prior experience with polyclonal antibodies. 相似文献
8.
Michael Rosenzweig Martha Skinner Tatiana Prokaeva Roger Théberge Catherine Costello Brian M Drachman Lawreen H Connors 《Amyloid》2007,14(1):65-71
We report the identification of a new transthyretin (TTR) gene mutation and variant protein, Glu61Gly, in a 55-year-old man with progressive cardiomyopathy, mild peripheral neuropathy and bilateral carpal tunnel syndrome. A diagnosis of TTR-associated familial amyloidosis (ATTR) was considered after an endomyocardial biopsy revealed amyloid deposits in the heart of a patient who had no family history of amyloidosis and no evidence of a plasma cell dyscrasia. Serum screening for a TTR variant by isoelectric focusing (IEF) was positive and prompted further studies to identify the genetic abnormality and to characterize the amyloidogenic protein. Direct DNA sequence analysis of all four coding regions in the TTR gene demonstrated heterozygosity in exon 3. Near equal amounts of guanine (G) and adenine (A) were observed at the second base position of codon 61. The wild-type (GAG) and mutated (GGG) sequences found in codon 61 correspond to glutamic acid (Glu) and glycine (Gly) residues, amino acids which differ in mass by -72 Da. Mass spectrometric analyses of TTR immunoprecipitated from serum showed the presence of both wild-type and variant proteins. The observed mass results for the wild-type and variant proteins were consistent with the predicted values calculated from the genetic analysis data. 相似文献
9.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
10.