全文获取类型
收费全文 | 20435篇 |
免费 | 1910篇 |
国内免费 | 41篇 |
专业分类
耳鼻咽喉 | 254篇 |
儿科学 | 634篇 |
妇产科学 | 521篇 |
基础医学 | 2785篇 |
口腔科学 | 345篇 |
临床医学 | 2760篇 |
内科学 | 3632篇 |
皮肤病学 | 299篇 |
神经病学 | 2265篇 |
特种医学 | 685篇 |
外国民族医学 | 2篇 |
外科学 | 2529篇 |
综合类 | 418篇 |
一般理论 | 19篇 |
预防医学 | 2364篇 |
眼科学 | 474篇 |
药学 | 1236篇 |
中国医学 | 25篇 |
肿瘤学 | 1139篇 |
出版年
2022年 | 151篇 |
2021年 | 342篇 |
2020年 | 249篇 |
2019年 | 326篇 |
2018年 | 450篇 |
2017年 | 336篇 |
2016年 | 331篇 |
2015年 | 324篇 |
2014年 | 537篇 |
2013年 | 768篇 |
2012年 | 1087篇 |
2011年 | 1020篇 |
2010年 | 550篇 |
2009年 | 524篇 |
2008年 | 900篇 |
2007年 | 926篇 |
2006年 | 908篇 |
2005年 | 937篇 |
2004年 | 864篇 |
2003年 | 816篇 |
2002年 | 730篇 |
2001年 | 563篇 |
2000年 | 564篇 |
1999年 | 505篇 |
1998年 | 230篇 |
1997年 | 194篇 |
1996年 | 164篇 |
1995年 | 221篇 |
1994年 | 257篇 |
1993年 | 209篇 |
1992年 | 448篇 |
1991年 | 414篇 |
1990年 | 373篇 |
1989年 | 361篇 |
1988年 | 380篇 |
1987年 | 332篇 |
1986年 | 343篇 |
1985年 | 313篇 |
1984年 | 262篇 |
1983年 | 249篇 |
1982年 | 171篇 |
1981年 | 150篇 |
1979年 | 255篇 |
1978年 | 172篇 |
1977年 | 146篇 |
1976年 | 159篇 |
1975年 | 152篇 |
1974年 | 182篇 |
1973年 | 155篇 |
1972年 | 141篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
T C Greiner C P Burns F R Dick K M Henry I Mahmood 《American journal of clinical pathology》1992,98(5):522-525
Congenital dyserythropoietic anemia type II is a rare disorder that is often diagnosed in patients before age 20 years. Patients with this disorder, which is also called hereditary erythroblastic multinuclearity associated with a positive acidified serum lysis test, may have symptoms of iron overload. The purpose of this case report is to alert physicians to consider the diagnosis of congenital dyserythropoietic anemia type II in elderly patients who have anemia and iron overload. 相似文献
102.
L H Lin S Bock K Carpenter M Rose J J Norden 《Brain research. Molecular brain research》1992,14(1-2):147-153
Metabolic labeling and quantitative 2D gel autoradiography were used to assess changes in the synthesis and transport of GAP-43 in entorhinal cortex (EC) neurons and perforant pathway during lesion-induced sprouting and reactive synaptogenesis. In normal adult rats, there is a high constitutive level of GAP-43 synthesis and transport in EC neurons projecting to the hippocampus. Following unilateral EC lesions, there is a 2-fold (100%) increase in the transport of newly synthesized GAP-43 to the contralateral or 'sprouting' hippocampus. The timing of this upregulation (between 6 and 15 days) suggests that changes in GAP-43 expression occur in response to the growth of presynaptic terminals during sprouting. 相似文献
103.
目的:观察卡巴胆碱(carbachol,Car)对酵母多糖致多器官功能障碍综合征(MODS)小鼠多脏器功能和结构损伤的防护作用。方法:采用腹腔注射酵母多糖的方法复制小鼠MODS模型。雄性C57BL/6小鼠随机分为正常对照组(n=10),MODS 6、24、48 h组(n=30)和MODS Car 6、24、48 h防治组(n=30)。MODS组在致伤后腹腔注入生理盐水;MODS Car防治组在致伤前24 h内分3次灌胃注入卡巴胆碱。观察酵母多糖致伤后早期(48h内)动物死亡率,检测各组血丙氨酸转氨酶活性、尿素氮和肌酐水平,镜下观察致伤后48 h动物肝、肺、肾、心等脏器的组织病理学改变。结果:在酵母多糖致伤后48h内,MODS组小鼠死亡率达26.6%,MODS Car防治组的小鼠死亡率为10.0%。MODS组小鼠血浆ALT、BUN和Cr在伤后6h升高,而同时间点经卡巴胆碱预处理的小鼠血浆ALT、BUN和Cr仅略有升高,明显低于MODS组。光镜下观察发现,MODS组小鼠肝脏、肺脏、肾脏和心脏发生明显的病理改变,主要表现为脏器实质细胞浊肿、变性,间质充血、水肿和炎性细胞浸润,而卡巴胆碱防治组小鼠上述病变明显减轻。结论:预防性给予卡巴胆碱可以降低MODS急性期动物的死亡率,减轻脏器功能和结构的损伤,对急性炎症期的脏器损伤具有保护作用。 相似文献
104.
Elliot L Dimberg Sheila E Crowe Joel M Trugman Russell H Swerdlow M Beatriz Lopes T David Bourne Ted M Burns 《Movement disorders》2007,22(3):407-411
We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed. 相似文献
105.
Dorothy Burns 《Applied Nursing Research》2004,17(2):116-124
Roy's Adaptation Model was used to study problems and coping strategies reported by 102 blacks on hemodialysis. Although the most frequently identified problems were fatigue, muscle soreness, and physical limitations, food and fluid restrictions were most bothersome. Participants used multiple strategies to cope with the illness and its treatment. Putting trust in God was the most frequently identified strategy. These findings can be used to enhance the physical and psychosocial assessment of these patients and facilitate the ability of clinicians to intervene effectively in helping clients cope with the problems that are associated with the illness and its treatment. 相似文献
106.
M Rosewich M A Rose O Eickmeier M Travaci R Kitz S Zielen 《The European respiratory journal》2007,30(1):56-61
The present study investigated whether single-dose oral leukotriene receptor antagonists as add-on therapy to short-acting beta-agonists, immediately after allergen challenge, block the late-phase airway response. In total, 35 mild asthmatics (mean age 24 yrs, 19 males) sensitised for house dust mites underwent two courses of bronchial allergen challenge. After the early allergic response (EAR), subjects received salbutamol once and were randomly assigned to either 10 mg of montelukast or placebo (double-blind crossover). To identify a late allergic response, forced expiratory volume in one second (FEV(1)) was monitored over the following 8 h. Baseline exhaled nitric oxide (NO) was determined ahead of each allergen challenge. Baseline NO levels differed significantly depending on the reaction to allergen challenge. In total, 12 subjects showed no significant response, 11 only showed an EAR, and 12 had a dual response and underwent further analysis. The area under the FEV(1) time-response curve 3-8 h after bronchial allergen challenge was -0.77+/-1.68 from the pre-challenge values on montelukast compared with -2.47+/-1.32 on placebo. The baseline exhaled NO fraction of subjects without an EAR was significantly lower than of those presenting a dual response. The results of the present study demonstrate that single-dose leukotriene receptor antagonists given orally right after the early allergic response can significantly inhibit the late allergic response after bronchial allergen challenge. 相似文献
107.
Although breast milk is recommended as the optimal source of infant nutrition, breastfeeding initiation is below recommended levels, especially among teenage mothers. Breastfeeding initiation rates among Michigan (US) teenage mothers (12-19 y) were compared by demographics and health behaviors. Multivariate analyses determined which factors were significant independent predictors of breastfeeding initiation among teenage mothers enrolled prenatally in the Michigan Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in 1995. Significant predictors independently associated with breastfeeding initiation were race/ethnicity, education, marital status, postpartum anemia status, parity, prenatal trimester of WIC enrollment, and smoking. The strongest predictor of breastfeeding initiation differed for white mothers (positive predictor: education beyond high school [OR = 3.13]) and black mothers (negative predictor: multiparous [OR = 0.25]). Initiation rates for this population of teenage mothers fall below the national average for mothers of all ages and the US Healthy People 2010 goals. Research is needed concerning how breastfeeding support and education can be improved to reach the US national health goals. 相似文献
108.
S D Hobbs M Yapanis P J Burns A B Wilmink A W Bradbury D J Adam 《European journal of vascular and endovascular surgery》2005,29(3):301-304
INTRODUCTION: Although up to a half of patients undergoing abdominal aortic aneurysm (AAA) repair suffer myocardial injury, as indicated by a rise in cardiac troponin I (cTnI), this is infrequently accompanied by a rise in creatine kinase (CK)-MB fraction or electrocardiogram (ECG) changes. This study compares for the first time peri-operative cTnI, CK-MB and ECG changes in patients undergoing surgery for critical lower limb ischaemia (CLI). METHODS: Twenty-nine patients (20 men, median age 75 [range, 57-95] years) were studied prospectively. cTnI, CK/CK-MB ratio and ECG were performed pre-operatively and on post-operative days 1, 2 and 3. RESULTS: Eleven (38%) patients had an elevated cTnI >0.5 ng/ml. Five (17%) patients had an elevated CK-MB fraction >4% and all of these patients had an elevated cTnI. Eleven (38%) patients had ischaemic changes on ECG including seven of 11 (64%) patients with elevated cTnI and all five patients with elevated CK-MB fraction. There was no relationship between pre-operative cardiac status, antiplatelet use or type of anaesthesia and post-operative cTnI rise. Patients with a cTnI rise were younger (p=0.01), and were more likely to have presented with gangrene (p=0.04) and have a longer operation time (p=0.01) than patients who did not demonstrate a cTnI rise. Four patients developed clinically apparent cardiac complications: cardio-pulmonary arrest (n=1), cardiogenic shock (n=1), acute CCF (n=1) and rapid atrial fibrillation (n=1). Survival at 6 months was 26 of 29 (90%) patients. CONCLUSION: These data demonstrate that over a third of patients operated for CLI sustain peri-operative myocardial injury, many of which are not clinically apparent. Pre-operative medical optimisation may improve prognosis in this group of patients. 相似文献
109.
Richard C Oude Voshaar Sube Banerjee Mike Horan Robert Baldwin Neil Pendleton Rebekah Proctor Nick Tarrier Yvonne Woodward Alistair Burns 《The American journal of geriatric psychiatry》2007,15(9):807-814
OBJECTIVE: Depression after hip fracture surgery is prevalent and associated with increased mortality rates and impaired functional recovery. The incidence of new-onset depressive symptoms in patients initially not depressed after hip fracture surgery and their relationship with functional recovery is unknown. METHODS: A cohort of 139 nondepressed elderly patients (>60 years) hospitalized for hip fracture surgery were followed up for six months. Clinically significant depressive symptoms were defined as a score of 7 or more on the 15-item Geriatric Depression Scale. RESULTS: The authors found a cumulative incidence rate of 20.5% adjusted for dropouts. Multiple Cox-regression analyses yielded the presence of subthreshold symptoms of depression, anxiety, pain, and cognitive impairment at baseline, the premorbid level of mobility, and a history of (treated) depression as risk factors for incident depression (p <0.05). A forward, conditional procedure identified postoperative pain (hazard ratio [HR] = 1.32, 95% confidence interval [CI]: 1.14-1.53, Wald chi(2) = 13.57, df = 1, p <0.001) and baseline anxiety (HR = 1.25, 95% CI: 1.08-1.44, Wald chi(2) = 8.86, df = 1, p = 0.003) as the strongest independent risk factors. Incident depression was associated with a less favorable outcome at 3 months follow-up. CONCLUSION: This exploratory study identified two treatable baseline characteristics that predicted incident depression in nondepressed patients after hip-fracture surgery. 相似文献