全文获取类型
收费全文 | 5520篇 |
免费 | 251篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 97篇 |
儿科学 | 331篇 |
妇产科学 | 69篇 |
基础医学 | 743篇 |
口腔科学 | 92篇 |
临床医学 | 345篇 |
内科学 | 975篇 |
皮肤病学 | 101篇 |
神经病学 | 348篇 |
特种医学 | 93篇 |
外科学 | 723篇 |
综合类 | 181篇 |
一般理论 | 6篇 |
预防医学 | 414篇 |
眼科学 | 156篇 |
药学 | 653篇 |
中国医学 | 34篇 |
肿瘤学 | 418篇 |
出版年
2023年 | 43篇 |
2022年 | 144篇 |
2021年 | 217篇 |
2020年 | 125篇 |
2019年 | 145篇 |
2018年 | 164篇 |
2017年 | 109篇 |
2016年 | 146篇 |
2015年 | 189篇 |
2014年 | 237篇 |
2013年 | 252篇 |
2012年 | 421篇 |
2011年 | 414篇 |
2010年 | 225篇 |
2009年 | 175篇 |
2008年 | 315篇 |
2007年 | 284篇 |
2006年 | 303篇 |
2005年 | 228篇 |
2004年 | 224篇 |
2003年 | 190篇 |
2002年 | 143篇 |
2001年 | 114篇 |
2000年 | 112篇 |
1999年 | 99篇 |
1998年 | 48篇 |
1997年 | 35篇 |
1996年 | 21篇 |
1995年 | 20篇 |
1994年 | 18篇 |
1993年 | 33篇 |
1992年 | 59篇 |
1991年 | 38篇 |
1990年 | 35篇 |
1989年 | 61篇 |
1988年 | 45篇 |
1987年 | 22篇 |
1986年 | 30篇 |
1985年 | 29篇 |
1984年 | 24篇 |
1983年 | 38篇 |
1981年 | 14篇 |
1980年 | 18篇 |
1979年 | 23篇 |
1978年 | 13篇 |
1975年 | 11篇 |
1973年 | 18篇 |
1972年 | 13篇 |
1971年 | 12篇 |
1970年 | 13篇 |
排序方式: 共有5779条查询结果,搜索用时 15 毫秒
1.
2.
Joseph F. Levy Rahul Khairnar Alexander V. Louie Timothy N. Showalter C. Daniel Mullins Mark V. Mishra 《Practical radiation oncology》2019,9(2):e172-e179
Purpose
A hydrogel rectal spacer (HRS) is a medical device that is approved by the U.S. Food and Drug Administration to increase the separation between the prostate and rectum. We conducted a cost-effectiveness analysis of HRS use for reduction in radiation therapy (RT) toxicities in patients with prostate cancer (PC) undergoing external beam RT (EBRT).Methods and Materials
A multistate Markov model was constructed from the U.S. payer perspective to examine the cost-effectiveness of HRS in men with localized PC receiving EBRT (EBRT alone vs EBRT + HRS). The subgroups analyzed included site of HRS placement (hospital outpatient, physician office, ambulatory surgery center) and proportion of patients with good baseline erectile function (EF). Data on EF, gastrointestinal and genitourinary toxicities incidence, and potential risks associated with HRS implantation were obtained from a recently published randomized clinical trial. Health utilities and costs were derived from the literature and the 2018 Physician Fee Schedule and were discounted 3% annually. Quality-adjusted life years (QALYs) and costs were modeled for a 5-year period from receipt of RT. Probabilistic sensitivity analysis and value-based threshold analyses were conducted.Results
The per-patient 5-year incremental cost for spacers administered in a hospital outpatient setting was $3578, and the incremental effectiveness was 0.0371 QALYs. The incremental cost-effectiveness ratio was $96,440/QALY for patients with PC undergoing HRS insertion in a hospital and $39,286/QALY for patients undergoing HRS insertion in an ambulatory facility. For men with good baseline EF, the incremental cost-effectiveness ratio was $35,548/QALY and $9627/QALY in hospital outpatient and ambulatory facility settings, respectively.Conclusions
Based on the current Medicare Physician Fee Schedule, HRS is cost-effective at a willingness to pay threshold of $100,000. These results contain substantial uncertainty, suggesting more evidence is needed to refine future decision-making. 相似文献3.
Metabolic abnormalities of gastrointestinal mucosa in celiac disease: An in vitro proton nuclear magnetic resonance spectroscopy study
下载免费PDF全文
![点击此处可从《Journal of gastroenterology and hepatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
4.
Pankaj Kumar Mishra 《European journal of cardio-thoracic surgery》2006,29(5):861-2; author reply 862
5.
OBJECTIVE: To analyse morbidity after completion total thyroidectomy compared with primary total thyroidectomy in a specialist thyroid surgery centre. DESIGN: Retrospective study. SETTING: Tertiary referral hospital, India. PATIENTS: Medical records of 143 patients who had total thyroidectomy between January 1990 and December 1999. 95 had primary thyroidectomies and 48 were completion thyroidectomies. MAIN OUTCOME MEASURES: Complication rate in both groups. RESULTS: The groups were comparable in respect of clinicopathological variables. Residual tumour was found in 19/48 (40%). After completion thyroidectomy, transient hypoparathyroidism and transient recurrent laryngeal nerve palsy were recorded in 8/48 (17%) and 2/48 (4%), respectively. No permanent hypoparathyroidism or permanent recurrent laryngeal nerve palsy was recorded in the completion thyroidectomy group. CONCLUSIONS: Completion thyroidectomy can be done with acceptable morbidity in a specialist thyroid surgery centre. Fear of increased morbidity after the procedure should not deter surgeon from doing this operation or referring the patients to a specialist centre. 相似文献
6.
A Girdhar B Mishra R K Lavania A K Bagga G N Malaviya B K Girdhar 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1989,57(2):472-475
Two infants, one 4 months old and the other 2 months old, having histologically confirmed indeterminate leprosy are reported. The route of infection, mode of transmission, and incubation period are discussed with reference to these two cases of infantile leprosy. 相似文献
7.
Girish S. Mishra Arpan Bhatia 《Indian journal of otolaryngology and head and neck surgery》2007,59(3):296-297
Dermatofibrosarcoma protuberance of head and neck is a rare neoplasm and accounts for less than one percent of Head and Neck Neoplasm. The objective of this report is to understand etiology, presentation, histopathologic identification and treatment option for this tumour. The goal of current report is to acquaint the clinician with presentation and treatment option for this disease. 相似文献
8.
Simultaneous Quantification of an Enantiomer and the Racemic Compound of Ibuprofen by X-ray Powder Diffractometry 总被引:1,自引:0,他引:1
Purpose. An X-ray powder diffractometric method was developed for the simultaneous quantification of the relative amounts of the racemic compound (±) of ibuprofen (I) and S(+)-ibuprofen (II), when they occur as a mixture.
Methods. The X-ray powder diffraction patterns of I and II show pronounced differences. This formed the basis for the determination of the relative amounts of I and II when they occur as a mixture. X-ray lines with d-spacings of 14.41 and 4.37 Å were unique to I and II, respectively. Mixtures containing different proportions of I and II were prepared which also contained lithium fluoride (III) as an internal standard.
Results. A linear relationship was obtained when the intensity ratio (intensity of the 4.37 Å line of II/intensity of the 2.01 Å line of III) was plotted as a function of the weight fraction of II in the mixture. Similar results were obtained in the case of I. Using these standard curves, the weight fractions of I and II in 'unknown' mixtures were determined. The experimentally determined analyte concentration ranged between 98 and 104% of the true value. The relative error in the analyses of individual samples was < 10%. The minimum detectable weight fraction of I in II and II in I were 0.032 (3.2% w/w) and 0.034 (3.4% w/w), respectively. The minimum quantifiable weight fractions were 0.136 for I and 0.112 for II. Since the X-ray diffraction patterns of S(+)-ibuprofen and R(–)-ibuprofen are identical, the conclusions drawn regarding mixtures of I and II will also hold true in the quantitative analyses of mixtures of I and R(–)-ibuprofen. 相似文献
9.
Z. S. Meharwal N. Trehan V. M. Kohli V. K. Sharma R. R. Kasliwal A. Mishra V. Kohli A. Jayant 《Indian Journal of Thoracic and Cardiovascular Surgery》1992,8(2):88-91
Between November 1988 and February 1992, 416 patients required coronary endarterectomy for diffuse coronary artery disease.
This constitutes 16.19 per cent of all patients who underwent coronary artery bypass grafting during the same period. A total
of 528 endarterectomies were performed. Four-hundred and twenty-two endarterectomies were performed on right coronary system
and 106 endarterectomies were performed on left coronary system. One-hundred and twelve (26.92%) patients required more than
one endarterectomies.
The hospital mortality was 2.16 percent. 3.37 per cent of patients had perioperative infarction. Intraaortic balloon pump
was required in 1.92 per cent of patients. 5.77 per cent of the patients had significant arrhythmias. The patients have been
followed up for a mean period of 27 months. One-hundred and forty patients were evaluated by exercise multigated radionuclide
angiogram. One-hundred and thirty-four (95.71%) patients showed increase in ejection fraction as compared to preoperative
value. Six (4.29%) patients did not show any significant change while eight (5.71%) patients had fall in ejection fraction.
Postoperative coronary angiogram was done in 44 patients at a mean of 10 months. 89.59 per cent of grafts to the endarterectomised
vessels and 91.67% of grafts to nonendarterectomised vessel were patent. The difference between the two groups was not statistically
significant. 相似文献
10.
Caroline Bolton-Smith Marion E T McMurdo Colin R Paterson Patricia A Mole Julia M Harvey Steven T Fenton Celia J Prynne Gita D Mishra Martin J Shearer 《Journal of bone and mineral research》2007,22(4):509-519
Dietary supplementation with vitamin K(1), with vitamin D(3) and calcium or their combination, was examined in healthy older women during a 2-year, double-blind, placebo-controlled trial. Combined vitamin K with vitamin D plus calcium was associated with a modest but significant increase in BMC at the ultradistal radius but not at other sites in the hip or radius. INTRODUCTION: The putative beneficial role of high dietary vitamin K(1) (phylloquinone) on BMD and the possibility of interactive benefits with vitamin D were studied in a 2-year double-blind, placebo-controlled trial in healthy Scottish women > or =60 years of age. MATERIALS AND METHODS: Healthy, nonosteoporotic women (n = 244) were randomized to receive either (1) placebo, (2) 200 microg/day vitamin K(1), (3) 10 microg (400 IU) vitamin D(3) plus 1000 mg calcium/day, or (4) combined vitamins K(1) and D(3) plus calcium. Baseline and 6-month measurements included DXA bone mineral scans of the hip and wrist, markers of bone turnover, and vitamin status. Supplementation effects were tested using multivariate general linear modeling, with full adjustment for baseline and potential confounding variables. RESULTS: Significant bone mineral loss was seen only at the mid-distal radius but with no significant difference between groups. However, women who took combined vitamin K and vitamin D plus calcium showed a significant and sustained increase in both BMD and BMC at the site of the ultradistal radius. Serum status indicators responded significantly to respective supplementation with vitamins K and D. Over 2 years, serum vitamin K(1) increased by 157% (p < 0.001), the percentage of undercarboxylated osteocalcin (%GluOC) decreased by 51% (p < 0.001), serum 25-hydroxyvitamin D [25(OH)D] increased by 17% (p < 0.001), and PTH decreased by 11% (p = 0.049). CONCLUSIONS: These results provide evidence of a modest synergy in healthy older women from nutritionally relevant intakes of vitamin K(1) together with supplements of calcium plus moderate vitamin D(3) to enhance BMC at the ultradistal radius, a site consisting of principally trabecular bone. The substantial increase in gamma-carboxylation of osteocalcin by vitamin K may have long-term benefits and is potentially achievable by increased dietary intakes of vitamin K rather than by supplementation. 相似文献