全文获取类型
收费全文 | 997423篇 |
免费 | 75240篇 |
国内免费 | 2616篇 |
专业分类
耳鼻咽喉 | 12961篇 |
儿科学 | 34466篇 |
妇产科学 | 28460篇 |
基础医学 | 145282篇 |
口腔科学 | 27715篇 |
临床医学 | 90269篇 |
内科学 | 193548篇 |
皮肤病学 | 22912篇 |
神经病学 | 79107篇 |
特种医学 | 38386篇 |
外国民族医学 | 305篇 |
外科学 | 149486篇 |
综合类 | 23738篇 |
一般理论 | 385篇 |
预防医学 | 77819篇 |
眼科学 | 22606篇 |
药学 | 71868篇 |
3篇 | |
中国医学 | 2030篇 |
肿瘤学 | 53933篇 |
出版年
2018年 | 10556篇 |
2017年 | 8235篇 |
2016年 | 9375篇 |
2015年 | 10594篇 |
2014年 | 14416篇 |
2013年 | 22001篇 |
2012年 | 28985篇 |
2011年 | 30829篇 |
2010年 | 18491篇 |
2009年 | 17436篇 |
2008年 | 28789篇 |
2007年 | 30461篇 |
2006年 | 30961篇 |
2005年 | 29637篇 |
2004年 | 28926篇 |
2003年 | 27797篇 |
2002年 | 26814篇 |
2001年 | 46926篇 |
2000年 | 48033篇 |
1999年 | 40262篇 |
1998年 | 11177篇 |
1997年 | 10096篇 |
1996年 | 10160篇 |
1995年 | 9775篇 |
1994年 | 9090篇 |
1993年 | 8480篇 |
1992年 | 32249篇 |
1991年 | 31458篇 |
1990年 | 31006篇 |
1989年 | 29874篇 |
1988年 | 27167篇 |
1987年 | 27325篇 |
1986年 | 25434篇 |
1985年 | 24602篇 |
1984年 | 18397篇 |
1983年 | 15516篇 |
1982年 | 9288篇 |
1981年 | 8375篇 |
1979年 | 16859篇 |
1978年 | 12217篇 |
1977年 | 10314篇 |
1976年 | 9754篇 |
1975年 | 10178篇 |
1974年 | 12317篇 |
1973年 | 11843篇 |
1972年 | 10884篇 |
1971年 | 10113篇 |
1970年 | 9375篇 |
1969年 | 8724篇 |
1968年 | 8104篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
Demosthenes B Panagiotakos Christos Pitsavos Christodoulos Stefanadis 《European journal of cardiovascular prevention and rehabilitation》2006,13(6):901-908
PURPOSE: Our aim was to evaluate whether healthy dietary habits, physical activity and non-smoking are associated with less severe acute coronary syndromes and better short-term prognosis. SUBJECTS AND METHODS: From October 2003 to September 2004, 2172 patients (1649 males), hospitalized for severe acute coronary syndromes in six major hospitals in Greece were included in the study. The severity of severe acute coronary syndromes was assessed through troponin-I and maximum creatinine kinase MB levels, while 30-day recurrent event rate (death or rehospitalization for cardiovascular disease, angioplasty or coronary artery bypass surgery) was used to evaluate the prognosis of the patients. A 'healthy index' that assessed adherence to the Mediterranean diet, moderate alcohol intake, physical activity and abstinence from smoking was developed (range 0-4). RESULTS: One unit increment in the healthy index was associated with -12.4+/-2.4 ng/ml decrease in troponin I levels (P=0.001) and -9.7+/-2.5 ng/ml decrease in maximum creatinine kinase MB levels (P=0.001). The in-hospital mortality rate was 3.2% in males and 5.7% in females (i.e. overall 82 deaths, P=0.009); during the first 30 days following hospitalization the event rate was 15.7% in males and 16.3% in females (P=0.001). Values of the healthy index above one (i.e. presence of two or more protective factors) seemed to be associated with 44-84% lower risk of having recurrent events (P<0.001), even after various adjustments were made. CONCLUSION: Among patients who had had severe acute coronary syndromes, a healthy lifestyle seemed to be associated with less severe cardiac events and lower risk of death or rehospitalization 30 days after the event. 相似文献
22.
Chronic transplant dysfunction is a complex dynamic pathogenic process. Clinically, a decrease in glomerular filtration rate (GFR) becomes apparent leading to chronic renal insufficiency and dialysis or death from cardiovascular events. Chronic transplant dysfunction can develop into a chronic alIograft nephropathy (CAN) as a specific entity with dynamic progression. CAN includes a collection of immunologic and non-immunologic factors, rejection, ischemia time, donor and recipient characteristics and toxicity of calcineurin inhibitors. Despite improvements in immunosuppression, the long-range prognosis of renal allografts has not improved. Whether modern immunosuppressive concepts with reduction or avoidance of calcineurin inhibitors and a therapy based on antimetabolites, such as mycophenolate or mTOR-inhibitors could lead to a prolongation of transplant survival, remains to be seen. 相似文献
23.
24.
G Steinitz M C Martín N Gazit-Yaari M L Quesada J de la Nuez R Casillas U Malik Z B Begin 《Applied radiation and isotopes》2006,64(4):520-524
Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes. 相似文献
25.
D B Irving J L Cook H B Menz 《Journal of Science and Medicine in Sport》2006,9(1-2):11-22; discussion 23-4
26.
A method is presented for 3D MRI in an extended field of view (FOV) based on continuous motion of the patient table and an efficient acquisition scheme. A gradient-echo MR pulse sequence is applied with lateral (left-right (L/R)) frequency-encoding direction and slab selection along the direction of motion. Compensation for the table motion is achieved by a combination of slab tracking and data alignment in hybrid space. The method allows fast k-space coverage to be achieved, especially when a short sampling FOV is chosen along the direction of table motion, as is desirable for good image quality. The method can be incorporated into different acquisitions schemes, including segmented k-space scanning, which allows for contrast variation with the use of magnetization preparation. Head-to-toe images of volunteers were obtained with good quality using 3D spoiled gradient-echo sequences. As an example of magnetization-prepared imaging, fat/water separated images were acquired using chemical shift selective (CHESS) presaturation pulses. 相似文献
27.
28.
A-C Koschker M Fassnacht S Hahner D Weismann B Allolio 《Experimental and clinical endocrinology & diabetes》2006,114(2):45-51
BACKGROUND: Adrenocortical carcinoma (ACC) is a rare and highly malignant tumour with a poor prognosis. Patients present with signs of steroid hormone excess (e.g., Cushing's syndrome) or symptoms due to an abdominal mass. DIAGNOSIS: In case of an adrenal mass, hormonal workup before surgery is required for differential diagnosis, perioperative management, and for follow-up. The imaging of choice is CT or MRI with MRI being of additional use when invasion of big vessels is suspected. Apart from that, the use of 18-FDG-PET is becoming increasingly established. TREATMENT: Surgical resection is the therapeutic option of choice in stages 1 - 3. In stage 4, the adrenolytic compound mitotane is part of the first-line treatment, but often needs to be combined with cytotoxic chemotherapy. Most patients will eventually have a recurrence, so adjuvant treatment (mitotane/tumour bed radiation) has to be considered in high risk patients, even if randomized controlled trials on adjuvant treatment are still lacking. STRUCTURAL PROGRESS: Several national and European structures have recently been established in order to increase our knowledge of ACC, improve therapeutic options and diagnostic procedures, and promote research. GANIMED, as a Germany-wide network of experts on adrenal diseases, has been founded allowing for improved gathering of data and joint studies. ENSAT (European Network for the Study of Adrenal Tumours) has been brought to life, aiming at European standards for therapy, diagnosis and tumour banking. Since 2003, patients can be enrolled in the German ACC Registry. France and Italy have also developed a central registry to collect nationwide data from patients with ACC. For the first time, patients with metastatic/unresectable ACC can participate in a prospective controlled randomized trial comparing two different cytotoxic chemotherapy regimes (FIRM-ACT). 相似文献
29.
B Dederichs M Dietlein B Jenniches-Kloth M Schmidt P Theissen D Moka H Schicha 《Experimental and clinical endocrinology & diabetes》2006,114(7):366-370
BACKGROUND: Radioiodine therapy (RIT) combined with glucocorticoids is an effective therapy for Graves' disease, but it is debatable whether glucocorticoids should be applied in patients without Graves' ophthalmopathy (GO). METHODS: The effect of 0.4 - 0.5 mg prednisone every second day over a period of 5 weeks after RIT was monitored over a follow-up period of at least 12 months after RIT. A questionnaire was sent to 186 consecutive patients without GO concerning eye symptoms after RIT. 148 patients (80 %) answered. If eye symptoms had occurred after RIT, additional clinical examination was carried out at our outpatient clinic. The primary endpoint was the absence or onset of GO within the first year after RIT. RESULTS: Within 12 months after RIT the examination confirmed GO in 5 out of 148 patients (3.4 %). In all cases the symptoms were transient. No adverse reaction to the use of prednisone after RIT was noted. CONCLUSIONS: The risk of new GO in the first year after RIT was low and the clinical course of GO was mild when RIT was combined with a low-dose glucocorticoid regimen. Preventive administration of glucocorticoids can therefore be recommended in patients with Graves' disease even without evident GO. 相似文献
30.
M Vitacca M Paneroni L Bianchi E Clini A Vianello P Ceriana L Barbano B Balbi S Nava 《The European respiratory journal》2006,27(2):343-349
The present study compared four different sites and conditions for the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in 38 spontaneous breathing tracheotomised patients. Of the patients, 28 had chronic obstructive pulmonary disease (COPD). The four different conditions were: 1) through a cuff inflated cannula (condition A); 2) through the mouth with a deflated cannula (condition B); 3) through the mouth with a phonetic uncuffed cannula (condition C); and 4) through the mouth after stoma closure (condition D). Five trials in each condition were performed using a standardised method. The measurement of both MIP and MEP differed significantly depending on the condition of measurement. MIP taken in condition A was significantly higher when compared with conditions B, C and D. MEP in condition A was significantly higher when compared with condition B and D. In condition A the highest frequency of the best measurement of MIP and MEP was observed at the fourth and fifth effort, respectively. The same results were obtained after the selection of only COPD patients. In conclusion, respiratory muscle assessment differs significantly depending on measurement condition. Measurement through inflated cannula tracheotomy yields higher values of both maximal inspiratory and maximal expiratory pressure. 相似文献