全文获取类型
收费全文 | 362808篇 |
免费 | 18952篇 |
国内免费 | 1231篇 |
专业分类
耳鼻咽喉 | 4645篇 |
儿科学 | 11299篇 |
妇产科学 | 8098篇 |
基础医学 | 51572篇 |
口腔科学 | 9805篇 |
临床医学 | 28242篇 |
内科学 | 80758篇 |
皮肤病学 | 10492篇 |
神经病学 | 32066篇 |
特种医学 | 10250篇 |
外国民族医学 | 133篇 |
外科学 | 44381篇 |
综合类 | 2825篇 |
一般理论 | 109篇 |
预防医学 | 33881篇 |
眼科学 | 7178篇 |
药学 | 25518篇 |
6篇 | |
中国医学 | 1551篇 |
肿瘤学 | 20182篇 |
出版年
2023年 | 1991篇 |
2022年 | 2676篇 |
2021年 | 7793篇 |
2020年 | 4396篇 |
2019年 | 7641篇 |
2018年 | 11494篇 |
2017年 | 7580篇 |
2016年 | 7557篇 |
2015年 | 8463篇 |
2014年 | 10400篇 |
2013年 | 15420篇 |
2012年 | 24487篇 |
2011年 | 25224篇 |
2010年 | 13211篇 |
2009年 | 10768篇 |
2008年 | 20765篇 |
2007年 | 21967篇 |
2006年 | 20309篇 |
2005年 | 20208篇 |
2004年 | 18747篇 |
2003年 | 17299篇 |
2002年 | 16326篇 |
2001年 | 9696篇 |
2000年 | 10048篇 |
1999年 | 8552篇 |
1998年 | 2218篇 |
1997年 | 1766篇 |
1996年 | 1563篇 |
1995年 | 1430篇 |
1994年 | 1192篇 |
1993年 | 1062篇 |
1992年 | 4324篇 |
1991年 | 3884篇 |
1990年 | 3679篇 |
1989年 | 3291篇 |
1988年 | 3071篇 |
1987年 | 2895篇 |
1986年 | 2712篇 |
1985年 | 2485篇 |
1984年 | 1864篇 |
1983年 | 1560篇 |
1979年 | 1563篇 |
1978年 | 1119篇 |
1975年 | 1080篇 |
1974年 | 1268篇 |
1973年 | 1282篇 |
1972年 | 1206篇 |
1971年 | 1189篇 |
1970年 | 1122篇 |
1969年 | 1158篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
J Segura M Anguita D Mesa E Romo R Vivancos J Suárez de Lezo F Vallés 《Revista espa?ola de cardiología》1991,44(9):625-627
The case of a patient in whom acute pericarditis was the initial manifestation of an idiopathic hypereosinophilia is reported. Endomyocardial abnormalities were not found by echocardiography. Response to prednisone therapy was good; symptoms, pericardial effusion and eosinophilia early disappeared after therapy. Some clinical aspects of this uncommon disease are discussed. 相似文献
993.
María de Gracia García-Martín María Violante de Paz Juan Antonio Galbis 《Macromolecular chemistry and physics.》1997,198(1):219-227
A chiral poly(3-substituted isobutyl D -aspartate) 12 was synthesized by polymerization of the chiral β-lactam 11 derived from D -glyceraldehyde. The new polyamide was characterized by elemental analyses, and infrared, 1H- and 13C nuclear magnetic resonance spectroscopies. The molecular weight was estimated as 543 000 and 230 000 on the basis of viscosimetric measurements and gel-permeation chromatography, respectively. Polyamide 12 is soluble in a variety of organic solvents including chloroform. 相似文献
994.
A method based on ion-exchange column chromatography to enhance the protein content of fruit allergenic extracts was found to help make the subsequent SDS-PAGE immunoblotting assays possible; otherwise, they were difficult to achieve due to the high carbohydrate content. Fractionated extracts of apple, pear, and peach (peel and pulp) were obtained by anion-exchange chromatography (Q-SepharoseTM column), providing clear electrophoretic patterns which allowed IgE detection by enzymatic assays of the transferred membranes. This chromatographic method produced in one single step an enriched extract directly from the standard crude aqueous one, with an increment in the protein content of more than sixfold, on average; thus, it proved to be more suitable than the usual chemical fractionation procedures. 相似文献
995.
996.
Cemal Şenyuva Akın Yücel Yagmur Aydın Ihsan Okur Zeki Güzel 《Aesthetic plastic surgery》1997,21(4):233-239
Extracorporeal septoplasty is a radical solution for the severely deviated nose. The major problems associated with this
procedure are fixation of the septal cartilage graft and dorsal irregularities. Extracorporeal septoplasty was performed in
combination with open rhinoplasty in 17 patients with severe nasal deformities. In this technique septum was totally removed
through the columellar incision of open rhinoplasty, corrected outside, and replaced as a free ``L' shaped cartilage graft.
The cartilage graft was fixated to the upper lateral cartilages to restore the natural relations of the anatomical structures.
Additional rhinoplastic manipulations were also performed. The follow-up period was up to 18 months. The overall result was
successful in all patients. Nasal deviation did not recur and secondary revisions were not needed for any patient during follow-up. 相似文献
997.
M. V. Hernández P. Peris N. Guañabens L. Alvarez A. Monegal F. Pons A. Ponce J. Muñoz-Gómez 《Calcified tissue international》1997,61(1):48-51
Moderate increases in ``classical' biochemical markers of bone turnover have been described only in some patients with Camurati–Engelmann
disease. However, the determination of the following ``new' markers has not been previously performed: serum osteocalcin
(BGP), bone alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), aminoterminal propeptide
of type I procollagen (PINP), tartrate-resistant acid phosphatase (TRAP), telopeptide carboxyterminal of type I collagen (ICTP),
urinary pyridinoline (PYR), crosslinked N-telopeptides of type I collagen (NTX), and Crosslaps (CL). Such a determination
may improve the evaluation of the disease activity. To evaluate the usefulness of biochemical markers of bone turnover reflecting
Camurati–Engelmann disease activity we measured the levels of all these markers in four affected patients. The results were
compared with bone scintigraphic indices of disease activity. Except for PICP and TRAP, bone formation and resorption markers
were abnormal in all patients and were related to bone scan indices of disease activity. Among the markers of bone formation
PINP, BAP, and BGP showed the highest values, whereas NTX and CL were the most sensitive markers of bone resorption. These
results suggest that the determination of NTX or CL, and PINP or either BAP and BGP, associated with bone scan evaluation,
provides the best assessment of Camurati–Engelmann disease activity.
Received: 14 June 1996 / Accepted: 31 December 1996 相似文献
998.
Summary A rapid and quantitative method for the determination of benzodiazepines using high-performance liquid chromatography (HPLC)
with diode-array detection (DAD) is reported. The drugs were extracted from serum, blood or post-mortem blood using C18 extraction columns. Brotizolam was used as internal standard. Experiments with spiked serum/blood samples resulted in recoveries
between 75% and 94% for all investigated benzodiazepines. Excellent linearity was obtained over the concentration range 5–1500
ng benzodiazepine/ml. The limit of detection was approximately 2 ng/ml. The detection of low therapeutic serum levels of highly
potent benzodiazepines is also possible.
相似文献
999.
Ana Ortega Ph.D. George Dranitsaris M.Sci.Phm. Jeremy Sturgeon M.D. Heather Sutherland M.Sci. Amit Oza M.D. 《Gynecologic oncology》1997,66(3):454-463
The standard treatment for patients with advanced ovarian cancer (AOC) has been cyclophosphamide and cisplatin (CP). Recently, the results of a large randomized comparative trial demonstrated that the combination of paclitaxel and cisplatin (TP) provided a progression-free survival benefit of 5 months. In this study, a cost–utility analysis was performed from a Canadian health care system perspective to estimate the incremental cost-effectiveness of the TP combination. Twelve AOC patients who received treatment with TP were matched for age and disease stage on a 1-to-2 basis with a CP control. Total hospital resource consumption was then collected for all patients. Treatment preferences were estimated from a cohort of 20 patients and 40 healthy female volunteers using the time trade-off technique. The outcomes were then generated through a decision-analytic model. First-line treatment costs with TP were approximately fourfold greater on a per-cycle basis than the CP alternative (Can$1911 vs Can$459). When progression-free survival benefit and patient treatment preferences were incorporated into the analysis, the results of the decision model revealed an incremental cost between Can$12,000 and Can$24,000 per quality-adjusted progression-free year with the TP protocol. Even though the TP combination has a considerably higher drug acquisition cost, the results of the current analysis suggest that this new chemotherapy regimen does provide patients with substantial quality-adjusted progression-free survival benefit at a reasonable cost to the Canadian health care system. 相似文献
1000.
Frédéric Bruckert Eric de Kerviler Anne-Marie Zagdanski Jean-Michel Molina Isabelle Casin A. Guermazi Janine Bédrossian Jacques Frija 《Skeletal radiology》1997,26(7):431-433
Bartonella henselae, previously called Rochalimaea henselae, is the causative agent of cat scratch disease (CSD) in immunocompetent subjects and bacillary angiomatosis in immunocompromised
ones. Bone lesions are common in bacillary angiomatosis, but not in CSD. We present the case of a patient with a renal transplant
treated by immunosuppressive therapy who developed a sternal abscess with a histological pattern of CSD. The CT pattern was
that of a lytic bone lesion with adjacent fluid collection. The diagnosis was made on the basis of a polymerase chain reaction
amplification performed on bone material. Bartonella henselae is a newly described bacteria that causes CSD in a normal host and bacillary angiomatosis in immunocompromised patients. We
report a case of an osteolytic lesion of the sternum with adjacent fluid collection related to CSD, which occurred in a patient
with a renal transplant. 相似文献