全文获取类型
收费全文 | 36903篇 |
免费 | 2016篇 |
国内免费 | 223篇 |
专业分类
耳鼻咽喉 | 359篇 |
儿科学 | 743篇 |
妇产科学 | 809篇 |
基础医学 | 4601篇 |
口腔科学 | 1396篇 |
临床医学 | 2721篇 |
内科学 | 10440篇 |
皮肤病学 | 1052篇 |
神经病学 | 3059篇 |
特种医学 | 686篇 |
外科学 | 5185篇 |
综合类 | 203篇 |
一般理论 | 11篇 |
预防医学 | 2703篇 |
眼科学 | 764篇 |
药学 | 2115篇 |
中国医学 | 129篇 |
肿瘤学 | 2166篇 |
出版年
2024年 | 26篇 |
2023年 | 287篇 |
2022年 | 654篇 |
2021年 | 1420篇 |
2020年 | 734篇 |
2019年 | 1265篇 |
2018年 | 1474篇 |
2017年 | 876篇 |
2016年 | 862篇 |
2015年 | 1070篇 |
2014年 | 1594篇 |
2013年 | 1833篇 |
2012年 | 3066篇 |
2011年 | 3233篇 |
2010年 | 1692篇 |
2009年 | 1563篇 |
2008年 | 2434篇 |
2007年 | 2492篇 |
2006年 | 2310篇 |
2005年 | 2142篇 |
2004年 | 1919篇 |
2003年 | 1622篇 |
2002年 | 1597篇 |
2001年 | 230篇 |
2000年 | 247篇 |
1999年 | 238篇 |
1998年 | 267篇 |
1997年 | 252篇 |
1996年 | 183篇 |
1995年 | 137篇 |
1994年 | 119篇 |
1993年 | 123篇 |
1992年 | 108篇 |
1991年 | 100篇 |
1990年 | 83篇 |
1989年 | 67篇 |
1988年 | 49篇 |
1987年 | 44篇 |
1986年 | 62篇 |
1985年 | 52篇 |
1984年 | 63篇 |
1983年 | 43篇 |
1982年 | 53篇 |
1981年 | 58篇 |
1980年 | 41篇 |
1979年 | 36篇 |
1976年 | 24篇 |
1975年 | 33篇 |
1973年 | 27篇 |
1971年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
35.
Sergi Sastre Francisco Maculé Sandra Lasurt Josep-María Segur Lluis Lozano Montse Nuñez Santiago Suso 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(4):393-397
Five patients with idiopathic transient osteoporosis were examined. Bone scanning and MRI was helpful in the diagnosis to differentiate of necrosis and all patients recovered completely with conservative and symptomatic treatment. There was no history of trauma in all patients. MRI was realized previously in all cases to confirm the diagnosis and after the resolution of symptomathology. 相似文献
36.
Javier Garzón Almudena López-Fando Pilar Sánchez-Blázquez 《Neuropsychopharmacology》2003,28(11):1983-1990
Members of the R7 subfamily of regulators of G-protein signaling (RGS) proteins (RGS6, RGS7, RGS9-2, and RGS11) are found in the mouse CNS. The expression of these proteins was effectively reduced in different neural structures by blocking their mRNA with antisense oligodeoxynucleotides (ODNs). This was achieved without noticeable changes in the binding characteristics of labeled beta-endorphin to opioid receptors. Knockdown of R7 proteins enhanced the potency of antinociception promoted by morphine and [D-Ala(2), N-MePhe(4), Gly-ol(5)]-enkephalin (DAMGO)-both agonists at mu-opioid receptors. The duration of morphine analgesia was greatly increased in RGS9-2 and in RGS11 knockdown mice. The impairment of R7 proteins brought about different changes in the analgesic activity of selective delta agonists. Knockdown of RGS11 reduced [D-Ala(2)]deltorphin II analgesic effects. Those of RGS6 and RGS9-2 proteins caused [D-Ala(2)]deltorphin II to produce a smoothened time-course curve-the peak effect blunted and analgesia extended during the declining phase. RGS9-2 impairment also promoted a similar pattern of change for [D-Pen(2,5)]-enkephalin (DPDPE). RGS7-deficient mice showed an increased response to both [D-Ala(2)]deltorphin II and DPDPE analgesic effects. A single intracerebroventricular (i.c.v.) ED(80) analgesic dose of morphine gave rise to acute tolerance in control mice, but did not promote tolerance in RGS6, RGS7, RGS9-2, or RGS11 knockdown animals. Thus, R7 proteins play a critical role in agonist tachyphylaxis and acute tolerance at mu-opioid receptors, and show differences in their modulation of delta-opioid receptors. 相似文献
37.
Mayte Ramirez Francisco Garcí a-Rí o Aleydis Vi as Concepci n Prados Jos M. Pino Jos Villamor 《The Journal of asthma》2005,41(1):109-116
The study objectives were to analyze the changes in exhaled carbon monoxide (COex) induced by histamine provocation challenge in asthmatic patients and to evaluate the relationship between COex and airway sensitivity and reactivity. Levels of COex were measured in 105 nonsmoking mildly asthmatic subjects before and after histamine provocation challenge. Dose-response curves were characterized by their sensitivity (PD20) and reactivity. Dose-response slope (DRS), continuous index of responsiveness (CIR), and bronchial reactivity index (BRI) were determined as reactivity indices. Bronchial challenge was positive for 47 subjects and negative for 58. The COex levels rose significantly after bronchial challenge in the positive response group (4.49 ± 0.4 vs. 5.74 ± 0.57 ppm, p = 0.025) and in the negative response group (2.84 ± 0.25 vs 4.00 ± 0.41 ppm, p = 0.000). An inverse relation between basal COex and PD20 was found (r = - 0.318, p = 0.030). In all subjects, a proportional direct relationship between COex and DRS (r = 0.214, p = 0.015), CIR (r = 0.401, p = 0.000), and BRI (r = 0.208, p = 0.012) was observed. On stepwise multiple linear regression analysis, COex only significantly correlated with CIR (multiple r2 = 0.174, p = 0.000). In conclusion, exhaled CO determination is a noninvasive inflammatory marker of the respiratory tract, which shows an acceptable association with airway hyperresponsiveness. 相似文献
38.
39.
David Jiménez Castro Gema Díaz David Martí Carlos Escobar Javier Ortega Sergio García-Rull Joaquin Picher Antonio Sueiro 《Blood coagulation & fibrinolysis》2007,18(2):173-177
This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization. 相似文献
40.