全文获取类型
收费全文 | 1131篇 |
免费 | 60篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 51篇 |
妇产科学 | 6篇 |
基础医学 | 106篇 |
口腔科学 | 54篇 |
临床医学 | 44篇 |
内科学 | 376篇 |
皮肤病学 | 10篇 |
神经病学 | 80篇 |
特种医学 | 32篇 |
外科学 | 218篇 |
综合类 | 2篇 |
预防医学 | 38篇 |
眼科学 | 11篇 |
药学 | 52篇 |
中国医学 | 1篇 |
肿瘤学 | 89篇 |
出版年
2023年 | 14篇 |
2022年 | 11篇 |
2021年 | 46篇 |
2020年 | 21篇 |
2019年 | 36篇 |
2018年 | 36篇 |
2017年 | 30篇 |
2016年 | 27篇 |
2015年 | 28篇 |
2014年 | 32篇 |
2013年 | 36篇 |
2012年 | 65篇 |
2011年 | 69篇 |
2010年 | 37篇 |
2009年 | 36篇 |
2008年 | 67篇 |
2007年 | 71篇 |
2006年 | 70篇 |
2005年 | 51篇 |
2004年 | 56篇 |
2003年 | 47篇 |
2002年 | 43篇 |
2001年 | 14篇 |
2000年 | 19篇 |
1999年 | 18篇 |
1998年 | 7篇 |
1997年 | 9篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 12篇 |
1991年 | 11篇 |
1990年 | 9篇 |
1989年 | 23篇 |
1988年 | 14篇 |
1987年 | 8篇 |
1986年 | 10篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1975年 | 9篇 |
1970年 | 3篇 |
1968年 | 4篇 |
1967年 | 4篇 |
排序方式: 共有1191条查询结果,搜索用时 156 毫秒
71.
72.
A cDNA fragment encoding the mitochondrial alternative oxidase, the enzyme responsible for cyanide-insensitive and salicylhydroxamic
acid (SHAM)-sensitive respiration, from the citric acid-producing fungus Aspergillus niger WU-2223L was cloned and expressed in Escherichia coli as a host strain. Synthetic primers were designed from the conserved nucleotide sequences of the alternative oxidase genes
from higher plants and a yeast. The 210-bp DNA fragment was amplified by PCR with these primers using chromosomal DNA of WU-2223L
as a template, and was employed to screen a cDNA library of A. niger. One full-length cDNA clone of 1.2 kb was obtained, and was sequenced to reveal that the clone contained an open reading
frame (ORF-AOX1) encoding a polypeptide of 351 amino acids. The predicted amino-acid sequence exhibited 50%, 55%, and 52%
homology to the alternative oxidases of Hansenula anomala, Neurospora crassa and Sauromatum guttatum, respectively. In the 5′-terminus region of the ORF-AOX1, a mitochondrial targeting motif was found. The whole open reading
frame of ORF-AOX1 was ligated to plasmid pKK223-3 to construct the expression vector pKAOX1. The E. coli transformant harboring pKAOX1 showed cyanide-insensitive and SHAM-sensitive respiration, and expression was increased approximately
two-fold by the addition of IPTG. These results indicated that the ORF-AOX1 encodes an alternative oxidase of A. niger.
Received: 10 August / 13 October 1998 相似文献
73.
74.
BACKGROUND: We investigated whether oral levofloxacin was as effective as intravenous cefazolin sodium for preventing postoperative infections in patients undergoing sagittal split ramus osteotomy of the mandible. METHODS: Forty-four patients were randomized to treatment with levofloxacin or cefazolin sodium. Levofloxacin (100 mg t.d.s.) was administered orally, and cefazolin sodium (1 g b.i.d.) by intravenous infusion. Both drugs were given until 5 days postoperatively. The concentrations of levofloxacin in the mandibular bone marrow and serum were measured. RESULTS: The mean levofloxacin concentration 4 h and 53.7 min after administration was 1.086 microg/ml in serum and 1.328 microg/ml in the mandibular bone marrow. The efficacy rate of levofloxacin was 95% and that of cefazolin sodium was 85.7%, with no significant difference between the two drugs (p = 0.322). CONCLUSION: Oral administration of levofloxacin is a simple, cost-effective and safe alternative to intravenous antibiotic prophylaxis after mandibular surgery. 相似文献
75.
Genya Mitani Yutaka Nakamura Takashi Miura Yuhei Harada Masato Sato Masahiko Watanabe 《Journal of orthopaedic science》2018,23(6):1056-1062
Background
Locomotive syndrome (LS) includes disorders of the musculoskeletal system and is a high-risk condition that requires nursing care. We included an examination of locomotive function in specific health checkups to investigate the relationship between LS risk and the muscle strengths. The purpose of this study was to determine the distribution of LS and the relationship between LS and metabolic syndrome (MetS).Methods
Among 2695 participants who undertook a specific health checkup, 790 received a locomotive examination (302 men and 488 women; mean age, 65.9 years). Data for MetS components were measured in the specific health checkup. Data about the locomotive examination were obtained from five tests: the two-step test, stand-up test, 25-question Geriatric Locomotive Function Scale, and measurement of lower limb muscular strength and grip strength.Results
The MetS components did not differ according to LS risk level in men. In women, body weight, body mass index, and abdominal circumference were significantly lower in the non-LS group than in the LS risk level 1 or 2 groups. The ratio of lower limb muscular strength to body weight differed significantly between all risk groups in men and women. In women, lower limb muscular strength was significantly higher in those at risk of both LS and MetS (double-risk group) than in the LS-only group. In women, the ratio of lower limb muscular strength to body weight was significantly lower in the double-risk group than in the LS-only group.Conclusions
Adding a locomotive examination to the specific health checkup may be useful for identifying people at risk of LS or MetS. The prevalence rates of LS and MetS correlate positively in women. The ratio of lower limb muscular strength to body weight might be a better index of locomotor dysfunction than lower limb muscular strength alone. 相似文献76.
Momotaro Kawai Atsushi Tanji Takayuki Nishijima Koichi Tateyama Yuhei Yoda Ai Iizuka Yusaku Kamata Tadahisa Urabe 《Journal of orthopaedic science》2018,23(6):987-991
Background
It remains unclear whether early surgical intervention can reduce mortality after surgery in hip fracture patients. The aim of this study was to investigate the association between time from injury to surgery and mortality rate within 90 days after hip fracture surgery.Methods
We retrospectively identified 1827 patients who underwent hip fracture surgery in a tertiary care center in Japan between April 2007 and March 2017. After applying exclusion criteria (patients with spontaneous fracture, multiple fractures, revision surgery, total hip arthroplasty, or a refusal to participate), 1734 patients were included. We extracted data concerning patients’ age, race, sex, operative procedure, American Society of Anesthesiologists (ASA) score, days from injury to surgery (injury-surgery days), and days from admission to surgery (admission-surgery days), which could affect 90-day mortality after surgery. Variables associated with 90-day mortality were determined using multivariate logistic regression analysis.Results
The 90-day postoperative mortality rate was 3.5% (60 of 1734). Multivariable analysis showed that injury-surgery days were not associated with 90-day mortality (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.80 to 1.05; P = 0.19), and that older age (OR, 1.06; 95% CI, 1.02 to 1.10; P = 0.005), male sex (OR, 3.62; 95% CI, 1.86 to 7.03; P < 0.001) and high ASA score (OR, 2.10; 95% CI, 1.06 to 4.18; P = 0.034) significantly increased 90-day mortality. In addition, admission-surgery days were not associated with 90-day mortality (OR, 0.95; 95% CI, 0.83 to 1.09; P = 0.45).Conclusion
Our results demonstrated that time from injury to surgery was not associated with mortality within 90 days after surgery after adjusting for age, sex, operative procedure, and ASA score. 相似文献77.
78.
79.
Sato Y Matsumoto N Kunimasa T Matsuo S Yoda S Tani S Kunimoto S Saito S Hirayama A 《International journal of cardiology》2008,131(1):e41-e43
We report a case of apical hypertrophic cardiomyopathy (HCM) presenting with non-sustained ventricular tachycardia. Whole-heart magnetic resonance imaging (MRI) showed normal coronary arteries and confirmed the diagnosis of apical HCM. First-pass gadolinium delayed-enhanced MRI showed local delayed enhancement in the endomyocardium in the hypertrophic lesion. The presence of perfusion defect and delayed enhancement may be a marker of a high-risk patient with apical HCM. 相似文献
80.
Shinya Yamamoto Satoru Kawakami Junji Yonese Yasuhisa Fujii Tetsuro Tsukamoto Yuhei Okubo Toshiki Kijima Yuichi Ishikawa Iwao Fukui 《International journal of urology》2010,17(8):720-725
Objectives: To investigate intraoperative and early postoperative complications of antegrade radical prostatectomy with intended wide resection (aRP) for clinically locally advanced prostate cancer (cLAD) and to compare with those of aRP for clinically localized prostate cancer (cLD). Methods: Between March 1994 and June 2007, 800 consecutive Japanese patients including 625 with cLD and 175 with cLAD underwent aRP and bilateral limited lymphadenectomy. Clinicopathological data including intraoperative and early postoperative complications (within 30 days after operation) were compared between cLD and cLAD groups. Results: No deaths occurred. Operative time and blood loss did not differ significantly between the groups. Intraoperative and early postoperative complications were observed in 11 (1.4%) and 123 (15.4%) of the entire cohort, respectively. Prevalent early postoperative complications were pelvic hematoma, wound infection, urinary retention and lymphocele or prolonged lymph drainage. There were no significant differences in the entire intraoperative and early postoperative complications between the groups. The majority of the early postoperative complications were minor. Conclusions: aRP for cLAD is technically feasible and a safe surgical procedure. If radical prostatectomy could be established as a standard treatment for cLAD in the future, aRP might be valuable as the first step of multimodal treatments. 相似文献