全文获取类型
收费全文 | 1444376篇 |
免费 | 81373篇 |
国内免费 | 1908篇 |
专业分类
耳鼻咽喉 | 18824篇 |
儿科学 | 46760篇 |
妇产科学 | 36504篇 |
基础医学 | 197954篇 |
口腔科学 | 37653篇 |
临床医学 | 119518篇 |
内科学 | 279207篇 |
皮肤病学 | 31504篇 |
神经病学 | 113614篇 |
特种医学 | 56392篇 |
外国民族医学 | 231篇 |
外科学 | 214974篇 |
综合类 | 24952篇 |
现状与发展 | 1篇 |
一般理论 | 301篇 |
预防医学 | 113320篇 |
眼科学 | 32129篇 |
药学 | 110040篇 |
7篇 | |
中国医学 | 4228篇 |
肿瘤学 | 89544篇 |
出版年
2021年 | 11695篇 |
2019年 | 11952篇 |
2018年 | 37451篇 |
2017年 | 28473篇 |
2016年 | 31921篇 |
2015年 | 16344篇 |
2014年 | 21369篇 |
2013年 | 30816篇 |
2012年 | 49494篇 |
2011年 | 64679篇 |
2010年 | 43185篇 |
2009年 | 34259篇 |
2008年 | 58789篇 |
2007年 | 63496篇 |
2006年 | 44276篇 |
2005年 | 43924篇 |
2004年 | 42880篇 |
2003年 | 41968篇 |
2002年 | 38725篇 |
2001年 | 66342篇 |
2000年 | 68448篇 |
1999年 | 56401篇 |
1998年 | 14003篇 |
1997年 | 12135篇 |
1996年 | 11975篇 |
1995年 | 11188篇 |
1994年 | 10069篇 |
1993年 | 9484篇 |
1992年 | 40585篇 |
1991年 | 38877篇 |
1990年 | 38281篇 |
1989年 | 36485篇 |
1988年 | 32912篇 |
1987年 | 31821篇 |
1986年 | 30059篇 |
1985年 | 28177篇 |
1984年 | 20441篇 |
1983年 | 17239篇 |
1982年 | 9504篇 |
1979年 | 18394篇 |
1978年 | 12325篇 |
1977年 | 11090篇 |
1976年 | 9629篇 |
1975年 | 11081篇 |
1974年 | 12911篇 |
1973年 | 12541篇 |
1972年 | 11958篇 |
1971年 | 11239篇 |
1970年 | 10368篇 |
1969年 | 10118篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
AIM: To assess the efficacy of intravesical botulinum toxin type A (BTX-A) in interstitial cystitis (IC). METHODS: Eleven patients with IC were injected with BTX-A. Primary outcome measures were: Bristol Female Lower Urinary Tract Symptom Score, Kings Health Questionnaire and 24-hour frequency-volume chart. They had urodynamics done before and six weeks after injection. Detrusor contractility was assessed using the modified PIP1 (projected isovolumetric detrusor pressure). 相似文献
992.
S Simona Jakab Victor J Navarro Beth W Colombe Constantine Daskalakis Steven K Herrine Simona Rossi 《Liver transplantation》2007,13(10):1405-1413
Human leukocyte antigen (HLA) compatibility has no clinically significant impact in cadaveric liver transplantation. Less is known regarding living-donor liver transplantation (LDLT). Our prior analysis of the Organ Procurement and Transplantation Network (OPTN) database suggested a higher graft failure rate in patients who underwent LDLT from donors with close HLA match. We further investigated the effect of HLA-A, -B, and -DR matching on 5-yr graft survival in adult LDLT by analyzing OPTN data regarding adult LDLT performed between 1998 and 2005. We evaluated associations between 5-yr graft survival and total, locus-specific, and haplotype match levels. Separate analyses were conducted for recipients with autoimmune (fulminant autoimmune hepatitis, cirrhosis secondary to autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis) or nonautoimmune liver disease. Multivariable Cox proportional hazard models were used to evaluate interactions and adjust for potential confounders. Among 631 patients with available donor/recipient HLA data, the degree of HLA match had no significant effect on 5-yr graft survival, even when analyzed separately in recipients with autoimmune vs. nonautoimmune liver disease. To be able to include all 1,838 adult LDLTs, we considered a first-degree related donor as substitute for a close HLA match. We found no difference in graft survival in related vs. unrelated pairs. In conclusion, our results show no detrimental impact of close HLA matching on graft survival in adult LDLT, including in recipients with underlying autoimmune liver disease. 相似文献
993.
994.
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
995.
R Depprich J Handschel J Hornung U Meyer N R Kübler 《Mund-, Kiefer- und Gesichtschirurgie》2007,11(1):19-26
BACKGROUND: Fractures of the mandible are a common form of facial injury. The aetiological factors associated with mandibular fractures and the trends in these factors over a 10-year period are reported. METHODS: A retrospective survey was carried out of 724 patients presenting with a fracture of the mandible over the 10-year-period 1994-2003. Patients; records were reviewed and analyzed according to age, sex, cause of injury, anatomic site of fracture, treatment and postoperative complications. RESULTS: Over the 10-year-period the rate of mandibular fractures remained constant (mean 40,7%). There were no changes in the age group (mean 33,3 years) or in the higher prevalence in male (male-female-ratio 2,3 : 1). The major causes of fractures were assaults (38,6%) and accidental fall (27,3%). The most common fracture site was the condylar region (47,0%) followed by the angle (29,4%). Most fractures were treated by closed reduction until 2002, thereafter surgical treatment increased noticeable. The complication rate was 8,9% and the most common complications were hardware exposure and infection. CONCLUSION: Fractures of the mandible are a prevalent form of facial injury. Aetiological factors show no significant change over the 10-year-period. Complication-rate is low and will support the tendency towards surgical treatment. 相似文献
996.
997.
998.
Sandra Urdaneta Hartmann Brian Wigdahl Elizabeth B Neely Cheston M Berlin Cara-Lynne Schengrund Hung-Mo Lin Mary K Howett 《Journal of human lactation》2006,22(1):61-74
Reduction of transmission of human immunodeficiency virus type 1 (HIV-1) through human milk is needed. Alkyl sulfates such as sodium dodecyl sulfate (SDS) are microbicidal against HIV-1 at low concentrations, have little to no toxicity, and are inexpensive. The authors have reported that treatment of HIV-1-infected human milk with < or = 1% (10 mg/mL) SDS for 10 minutes inactivates cell-free and cell-associated virus. The SDS can be removed with a commercially available resin after treatment without recovery of viral infectivity. In this article, the authors report results of selective biochemical analyses (ie, protein, immunoglobulins, lipids, cells, and electrolytes) of human milk subjected to SDS treatment and removal. The SDS treatment or removal had no significant effects on the milk components studied. Therefore, the use of alkyl sulfate microbicides to treat milk from HIV-1-positive women may be a simple, practical, and nutritionally sound way to prevent or reduce transmission of HIV-1 while still feeding with mother's own milk. 相似文献
999.
Major progress in clinical pain assessment and management has been achieved in the last decade. More effective analgesic drugs and improved techniques for pain management have been introduced. However, medical reports published during the last few years on postoperative pain management (POPM) indicate that moderate or even severe pain is still rather commonly experienced by surgical patients in the early postoperative period and that worst-pain-episodes may occur even in the late postoperative phase. Insufficient relief of postoperative pain seems a more common problem on surgical wards than on a postanaesthesia care unit (PACU). The aims of POPM are to inhibit autonomic trauma-induced nociceptive impulses that may result in functional disturbances of vital organs and thereby affect the incidence of potentially severe complications influencing clinical outcome. Considering that recent studies continue to show sub-optimal pain management despite the availability of effective drugs and analgesic techniques it must be considered essential to identify possible barriers to effective pain management in clinical practice so that necessary improvements in POPM routines can be carried out. 相似文献
1000.
Efficient high-frequency body coil for high-field MRI. 总被引:1,自引:0,他引:1
J T Vaughan G Adriany C J Snyder J Tian T Thiel L Bolinger H Liu L DelaBarre K Ugurbil 《Magnetic resonance in medicine》2004,52(4):851-859
The use of body coils is favored for homogeneous excitation, and such coils are often paired with surface coils or arrays for sensitive reception in many MRI applications. While the body coil's physical size and resultant electrical length make this circuit difficult to design for any field strength, recent efforts to build efficient body coils for applications at 3T and above have been especially challenging. To meet this challenge, we developed an efficient new transverse electromagnetic (TEM) body coil and demonstrated its use in human studies at field strengths up to 4 T. Head, body, and breast images were acquired within peak power constraints of <8 kW. Bench studies indicate that these body coils are feasible to 8 T. RF shimming was used to remove a high-field-related cardiac imaging artifact in these preliminary studies. P41RR13230 相似文献