全文获取类型
收费全文 | 35648篇 |
免费 | 2774篇 |
国内免费 | 354篇 |
专业分类
耳鼻咽喉 | 391篇 |
儿科学 | 965篇 |
妇产科学 | 957篇 |
基础医学 | 4558篇 |
口腔科学 | 582篇 |
临床医学 | 3710篇 |
内科学 | 7610篇 |
皮肤病学 | 831篇 |
神经病学 | 2413篇 |
特种医学 | 1166篇 |
外科学 | 4873篇 |
综合类 | 1173篇 |
一般理论 | 32篇 |
预防医学 | 1962篇 |
眼科学 | 1583篇 |
药学 | 2709篇 |
中国医学 | 307篇 |
肿瘤学 | 2954篇 |
出版年
2023年 | 265篇 |
2022年 | 511篇 |
2021年 | 959篇 |
2020年 | 615篇 |
2019年 | 781篇 |
2018年 | 997篇 |
2017年 | 762篇 |
2016年 | 868篇 |
2015年 | 1044篇 |
2014年 | 1375篇 |
2013年 | 1638篇 |
2012年 | 2343篇 |
2011年 | 2454篇 |
2010年 | 1404篇 |
2009年 | 1235篇 |
2008年 | 1912篇 |
2007年 | 1990篇 |
2006年 | 1992篇 |
2005年 | 1926篇 |
2004年 | 1700篇 |
2003年 | 1582篇 |
2002年 | 1414篇 |
2001年 | 1119篇 |
2000年 | 1051篇 |
1999年 | 904篇 |
1998年 | 355篇 |
1997年 | 262篇 |
1996年 | 242篇 |
1995年 | 194篇 |
1994年 | 188篇 |
1993年 | 187篇 |
1992年 | 452篇 |
1991年 | 439篇 |
1990年 | 419篇 |
1989年 | 394篇 |
1988年 | 346篇 |
1987年 | 366篇 |
1986年 | 320篇 |
1985年 | 272篇 |
1984年 | 203篇 |
1983年 | 146篇 |
1982年 | 94篇 |
1981年 | 85篇 |
1980年 | 89篇 |
1979年 | 138篇 |
1978年 | 89篇 |
1977年 | 72篇 |
1976年 | 76篇 |
1975年 | 77篇 |
1972年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
K. L. Chan 《Hernia》2007,11(1):37-40
Background Open repair of recurrent paediatric inguinal hernias (IH) is difficult and there is definite risk of damaging the vas deferens
and testicular vessels during dissection of the previous open herniotomy field. Laparoscopic repair (LR) has the benefit of
avoiding the previous operative site.
Method Records of patients with recurrent IH that had LR after open repair were reviewed and evaluated retrospectively. The results
were compared with data from cases in which the LR method was used in the initial IH repair.
Results From September 2002 to October 2005, four boys and one girl (mean age 58.8 months) were treated in our institution for recurrent
IH after open repair. Operative time, success rate and complications did not show any statistically significant difference
when compared with our previous prospectively collected data for primary repairs.
Conclusion Laparoscopic repair is the preferred operation for recurrent childhood IH after open repair. 相似文献
92.
Van Buskirk Glenn A. González Mario A. Shah Vinod P. Barnhardt Scott Barrett Colin Berge Stephen Cleary Gary Chan Keith Flynn Gordon Foster Thomas Gale Robert Garrison Raymond Gochnour Scott Gotto Amanda Govil Sharad Gray Vivian A. Hammar James Harder Samuel Hoiberg Charles Hussain Ajaz Karp Carol Llanos Hector Mantelle Juan Noonan Patrick Swanson David Zerbe Horst 《Pharmaceutical research》1997,14(7):848-852
Pharmaceutical Research - 相似文献
93.
为了比较中国内地城市和香港青少年儿童的心肺耐力和肌肉素质,对两地的青少年儿童体质调查数据进行了比较研究。结果发现:内地各年龄组男女生的心肺耐力均优于香港同龄者;香港青少年儿童的肌肉素质除立定跳远外,其他项目的成绩均弱于内地青少年儿童。提示:随着生活水平的提高,应重视青少年儿童对体育活动的参与。 相似文献
94.
Trisomy 8 and, less commonly tetrasomy 8, are karyotypic aberrations found in myeloid malignancies. We describe a unique case of acute myeloid leukemia with partial pentasomy 8 resulting from duplication of isochromosome 8q, and discuss its possible roles in leukemogenesis. 相似文献
95.
Deborah W. Knapp Ralph C. Richardson Gerald D. Bottoms Robert Teclaw Thomas C. K. Chan 《Cancer chemotherapy and pharmacology》1992,29(3):214-218
Summary Piroxicam, a nonsteroidal antiinflammatory drug, was given to 62 dogs bearing naturally occurring tumors in a phase I clinical trial. Dose escalation was performed, with oral doses ranging from 0.5 mg/kg every 48 h (q48h) to 1.5 mg/kg q48h being tested. Dose-limiting gastromestinal irritation/ulceration occurred in all four animals that received 1.5 mg/kg q48h. The maximum tolerated dose was 1 mg/kg q48h. Subclinical renal papillary necrosis occurred in two dogs (initial dosages, 1 and 1.5 mg/kg q48h, respectively). Following dose escalation, an additional group of dogs was treated with 0.3 mg/kg piroxicam q24h per os, the accepted canine dosage prior to this trial. Inclusion of this treatment group enabled evaluation of the toxicity of and tumor response to a daily dosage regimen. No complete remissions occurred in this trial. Partial remission was documented in three of ten dogs exhibiting transitional-cell carcinoma, in three of five animals bearing squamous-cell carcinoma, in one of three dogs displaying mammary adenocarcinoma, and in the one dog that exhibited a transmissible venereal tumor. The results of this study support the additional evaluation of piroxicam in a phase II clinical trial in dogs bearing naturally occurring tumors.This investigation was supported by Pfizer Inc. 相似文献
96.
A. C. W. Chan S. C. S. Chung A. P. C. Yim J. Y. W. Lau E. K. W. Ng A. K. C. Li 《Surgical endoscopy》1997,11(5):438-440
Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery. 相似文献
97.
A 46-year-old man presented with shock and adult respiratory distress syndrome. Investigations revealed an adrenal mass that was diagnosed, by fine-needle aspiration biopsy, as pheochromocytoma. Because biopsy is contraindicated in patients with pheochromocytoma, this confusing presentation underscores the value of excluding this diagnosis by biochemical means before performing fine-needle aspiration of adrenal tumours. 相似文献
98.
K Chan 《European journal of drug metabolism and pharmacokinetics》1986,11(2):129-134
p-Aminobenzoic acid (PABA), p-acetamidobenzoic acid (PADB) and p-aminohippuric acid (PAH) have been separated and determined by a reversed phase, isocratic high performance liquid chromatographic (HPLC) procedure simultaneously. The mobile phase, at 1.5 ml min-1, used was 10 mM sodium hydrogen phosphate buffer, pH 3.5, containing 40% methanol. The eluent was detected at 270 nm. Linear relationship was obtained from 0 to 2.0 micrograms ml-1 of each compound with the corresponding peak-height ratio using p-methylamino-benzoic acid (PMAB) as the internal standard. Urine samples were obtained from healthy Chinese volunteers after oral dosing of 200 mg PABA which was used as a model substance for metabolic investigation of N-acetylation and other conjugation reactions. The 24 hour urinary recovery, from 43 healthy subjects, of PABA, PABA-COOH conjugates, PADB and PADB-COOH conjugates were (mean +/- S.D.) 2.9 +/- 1.5%, 5.2 +/- 3.3%, 13.9 +/- 4.0% and 42.9 +/- 9.8% of the ingested dose respectively. These accounted for 64.9 +/- 12.0% of total dose ingested in 24 hour. In contrast to previously reported findings on one Caucasian subject, no PAH was identified in the urine, and N-acetylation was the major route of metabolism of PABA apart from conjugation at the -COOH group in this group of Chinese volunteers. It is proposed that PABA metabolism may be a useful probe to study ethnic and geographic variation in N-acetylation. 相似文献
99.
Our initial characterization of a herpes simplex virus type 1, temperature sensitive host shutoff mutant, called ts1-8, revealed that it has a low plaquing efficiency and exhibits a defect in the shutoff of host polypeptide synthesis and host DNA replication at the nonpermissive temperature of 39.5 degrees C. Using intratypic marker rescue experiments the ts plaquing mutation was mapped to a 557 bp region. Sequence analysis and complementation studies revealed that the low plaquing efficiency phenotype is due to a mutation in the glycoprotein B gene converting Pro-357 to Ser. This novel tsgB mutation is located in a conserved region of gB and it is distinct from the delayed host shutoff mutation (dhs). 相似文献
100.
Liver transplantation for chronic hepatitis B with lamivudine-resistant YMDD mutant using add-on adefovir dipivoxil plus lamivudine. 总被引:5,自引:0,他引:5
Chung Mau Lo Chi Leung Liu George K Lau See Ching Chan Irene O Ng Sheung Tat Fan 《Liver transplantation》2005,11(7):807-813
Lamivudine treatment in patients with chronic hepatitis B virus (HBV) infection may improve clinical state and suppress viral replication before liver transplantation. Emergence of lamivudine-resistant YMDD mutant is common. We report the results of liver transplantation in 16 patients with pretransplantation YMDD mutants after receiving lamivudine treatment for a median of 738 days (range, 400-1799 days). Adefovir dipivoxil (10 mg daily) was added on to lamivudine for a median of 20 days (range, 8-271 days) before (n = 11) or at (n = 5) liver transplantation, and the combination was continued indefinitely thereafter. Eight patients received additional intravenous hepatitis B immune globulin (HBIG) for a median of 24 months. Fifteen patients with known pre-adefovir HBV DNA levels had a median titer of 14,200 x 10(3) copies/mL (2 x 10(3) to 4,690,000 x 10(3) copies/mL), and 14 had HBV DNA >10(5) copies/mL. All but 1 patient remained positive for HBV DNA (by quantitative polymerase chain reaction [qPCR]) at the time of liver transplantation, and the titer was greater than10(5) copies/mL in 8 patients. The median follow-up after liver transplantation was 21.1 (range, 4.4-68.9) months. One patient (6%) died of an unrelated cause 12.2 months after transplantation, and 15 patients (94%) were alive with the original graft. All patients cleared HBV DNA and had no detectable HBV DNA by qPCR at the latest follow-up. Fourteen patients had cleared hepatitis B surface antigen (HBsAg), but 2 patients who received only adefovir dipivoxil and lamivudine without HBIG remained HBsAg positive after 7.7 and 9.5 months. Serum HBV DNA, however, was negative, and there was no biochemical or histological evidence of recurrence. Adefovir dipivoxil was well tolerated with no significant renal toxicity. In conclusion, a combination of add-on adefovir dipivoxil plus lamivudine therapy provides effective prophylaxis in patients with pretransplantation YMDD mutant that may be actively replicating. The cost effectiveness of additional passive immunoprophylaxis remains to be defined. 相似文献