全文获取类型
收费全文 | 250524篇 |
免费 | 39693篇 |
国内免费 | 2733篇 |
专业分类
耳鼻咽喉 | 6231篇 |
儿科学 | 7935篇 |
妇产科学 | 4043篇 |
基础医学 | 17918篇 |
口腔科学 | 3637篇 |
临床医学 | 36969篇 |
内科学 | 68184篇 |
皮肤病学 | 9170篇 |
神经病学 | 25398篇 |
特种医学 | 10430篇 |
外国民族医学 | 6篇 |
外科学 | 55038篇 |
综合类 | 1485篇 |
现状与发展 | 72篇 |
一般理论 | 74篇 |
预防医学 | 15027篇 |
眼科学 | 5048篇 |
药学 | 7926篇 |
中国医学 | 126篇 |
肿瘤学 | 18233篇 |
出版年
2023年 | 5208篇 |
2022年 | 2109篇 |
2021年 | 5225篇 |
2020年 | 7259篇 |
2019年 | 4144篇 |
2018年 | 9677篇 |
2017年 | 8989篇 |
2016年 | 10387篇 |
2015年 | 10744篇 |
2014年 | 18578篇 |
2013年 | 19756篇 |
2012年 | 12133篇 |
2011年 | 12216篇 |
2010年 | 14182篇 |
2009年 | 17693篇 |
2008年 | 11717篇 |
2007年 | 10493篇 |
2006年 | 12438篇 |
2005年 | 9710篇 |
2004年 | 8605篇 |
2003年 | 6979篇 |
2002年 | 7068篇 |
2001年 | 5592篇 |
2000年 | 4727篇 |
1999年 | 4797篇 |
1998年 | 4830篇 |
1997年 | 4422篇 |
1996年 | 4129篇 |
1995年 | 3983篇 |
1994年 | 2620篇 |
1993年 | 2183篇 |
1992年 | 2509篇 |
1991年 | 2450篇 |
1990年 | 2057篇 |
1989年 | 2129篇 |
1988年 | 1864篇 |
1987年 | 1649篇 |
1986年 | 1707篇 |
1985年 | 1531篇 |
1984年 | 1219篇 |
1983年 | 1090篇 |
1982年 | 1060篇 |
1981年 | 849篇 |
1980年 | 751篇 |
1979年 | 817篇 |
1978年 | 724篇 |
1977年 | 758篇 |
1975年 | 603篇 |
1974年 | 574篇 |
1972年 | 605篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
151.
152.
Lucia Nogovà MD Volker Diehl MD Andreas Engert MD 《Current hematologic malignancy reports》2006,1(1):60-65
Lymphocyte-predominant Hodgkin’s lymphoma (LPHL) differs in histologic and clinical presentation from classical Hodgkin’s
lymphoma (cHL). Treatment of LPHL patients using standard Hodgkin’s lymphoma protocols leads to complete remission in more
than 95% of patients. Survival and freedom from treatment failure are substantially worse in advanced-stage patients than
for early-stage patients. Thus, patients in advanced stages and those in early stages with unfavorable risk factors should
be treated similar to those with cHL. In contrast, patients with early-stage LPHL without risk factors might be sufficiently
treated with reduced-intensity programs having less severe adverse effects. As a result, treatment of early LPHL is rather
heterogeneous, including radiotherapy using extended-fleld technique, involved-fleld radiotherapy (IF-RT), combined-modality
treatment, and, more recently, monoclonal antibodies. Watch-and-wait strategy plays an important role in pediatric oncology,
to avoid adverse effects associated with therapy. IF-RT seems to be emerging as a treatment of choice for patients with stage
IA LPHL; most larger study groups, such as the German Hodgkin Study Group and the European Organisation for Research and Treatment
of Cancer, have adopted IF-RT as the treatment of choice for these patients. 相似文献
153.
154.
155.
Rajnish Mago MD John-Paul Gomez MD Namita Gupta MBBS Elisabeth J. S. Kunkel MD 《Current psychiatry reports》2006,8(3):228-233
Anxiety disorders and anxiety symptoms are highly prevalent in the general population and more so in the medically ill. They
have a number of negative consequences for these patients and may worsen the outcome of the medical illness and increase health
care utilization. In the evaluation of these patients, it is of paramount importance to identify the etiology of the anxiety
and, in particular, to differentiate primary from secondary anxiety. Management includes medications (especially benzodiazepines
and selective serotonin reuptake inhibitors) and psychotherapy (particularly cognitive-behavioral therapy). 相似文献
156.
Rosendo A. Rodriguez MD PhD Fraser Rubens MD MSc Carlos D. Rodriguez Howard J. Nathan MD 《Journal of neuroimaging》2006,16(2):126-132
OBJECTIVE: The application of intensity thresholds for embolus detection with transcranial Doppler (TCD) can exclude from analysis an unrecognized proportion of high-intensity transient signals (HITS))whose intensities are below the threshold. The lack of consistent threshold criteria between clinical trials may explain part of the discrepancy in the reported HITS counts. We investigated the effect of choosing different thresholds on the sensitivity and specificity of detecting HITS during cardiopulmonary bypass (CPB). METHODS: Two observers independently analyzed TCD recordings from 8 patients under CPB. Doppler signals were classified as true HITS, equivocal HITS, artifacts, and Doppler speckles according to preestablished criteria. The relative intensity of Doppler signals was measured by two different methods (TCD software vs manual). Receiver Operating Characteristic curves determined the optimal threshold for each of the two intensity methods. RESULTS: Reviewers achieved agreement in 96% of 2190 Doppler signals (kappa = 0.90). Relative intensities calculated with the TCD-software method were 3 dB (95% CI: 3.0-3.4) higher than the manual method. The optimal threshold was found at 10 dB (sensitivity: 99%; specificity: 90.8%) with the software method and at 7 dB with the manual method (sensitivity: 96%; specificity: 83%). The use of an intensity threshold 2 dB higher than the optimal increased the rejection of true HITS by 8% and 14%, respectively. CONCLUSIONS: Using intensity thresholds higher than the optimal for embolus detection decreases HITS counts. Choosing a threshold depends on the type of method used for measuring the signal intensity. Uniform threshold criteria and comparative studies between different Doppler devices are necessary for making clinical trials more comparable. 相似文献
157.
158.
Theodore C. Bania MD MS Tom Ashar MD Gregory Press MD Patricia M. Carey MD 《Academic emergency medicine》2003,10(7):697-704
Long-term daily use of gamma-hydroxybutyrate (GHB) and related compounds has recently been associated with a withdrawal syndrome. To the best of the authors' knowledge, there are currently no animal models of GHB withdrawal. OBJECTIVES: The authors studied and described the effect of chronic dosing of GHB (3-6 days) on tolerance and withdrawal in a rat model. METHODS: Rats were administered GHB every three hours via intraperitoneal catheter. Groups of rats (2 per group) were dosed with GHB for either 3 (24 doses), 4 (32 doses), 5 (40 doses), or 6 (48 doses) days. The GHB dose was 0.25 g/kg for doses 1-8, 0.75 g/kg for doses 9-12, 1 g/kg for doses 13-16, 1.25 g/kg for doses 17-24, 1.5 g/kg for doses 25-32, 1.75 g/kg for doses 33-40, and 2 g/kg for doses 41-48. Following the last dose of GHB, the rats were scored using a 16-point ethanol intoxication-withdrawal scale rating spontaneous behaviors, response to handling, grooming, and neurological signs. Lower scores indicate intoxication, while higher scores indicate withdrawal. Scores were recorded at hours 0, 1, 2, 3, 4, 5, 6, 9, 12, and 24. RESULTS: Tolerance: Rats dosed with GHB for more days were less intoxicated one hour after their last GHB dose despite receiving higher doses. WITHDRAWAL: The scores for all rats dosed with GHB increased at hours 4 (p = 0.028), 5 (p = 0.037), 6 (p = 0.007), and 9 (p = 0.024) after the last dose, indicating withdrawal. The scores demonstrated a linear increase dependent upon the number of days of GHB dosing at hours 3 (p < 0.000), 4 (p = 0.004), 5 (p = 0.002), and 12 (p = 0.039) as well as prior to the last dose at hour 0 (p = 0.000). No rats developed seizures. CONCLUSIONS: Tolerance and mild withdrawal in rats can be induced by administering intraperitoneal GHB every three hours for 3-6 days. More prolonged dosing and higher doses of GHB may be necessary to induce severe withdrawal. 相似文献
159.
Nephronophthisis related to homozygous NPHP1 gene deletion as a cause of chronic renal failure in adults. 总被引:1,自引:0,他引:1
160.
Hazel B Breitz Richard E Wendt Michael S Stabin Sui Shen William D Erwin Joseph G Rajendran Janet F Eary Lawrence Durack Ebrahim Delpassand William Martin Ruby F Meredith 《Journal of nuclear medicine》2006,47(3):534-542
166Ho-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene-phosphonate (DOTMP) is a tetraphosphonate molecule radiolabeled with 166Ho that localizes to bone surfaces. This study evaluated pharmacokinetics and radiation-absorbed dose to all organs from this beta-emitting radiopharmaceutical. METHODS: After two 1.1-GBq administrations of 166Ho-DOTMP, data from whole-body counting using a gamma-camera or uptake probe were assessed for reproducibility of whole-body retention in 12 patients with multiple myeloma. The radiation-absorbed dose to normal organs was estimated using MIRD methodology, applying residence times and S values for 166Ho. Marrow dose was estimated from measured activity retained after 18 h. The activity to deliver a therapeutic dose of 25 Gy to the marrow was determined. Methods based on region-of-interest (ROI) and whole-body clearance were evaluated to estimate kidney activity, because the radiotracer is rapidly excreted in the urine. The dose to the surface of the bladder wall was estimated using a dynamic bladder model. RESULTS: In clinical practice, gamma-camera methods were more reliable than uptake probe-based methods for whole-body counting. The intrapatient variability of dose calculations was less than 10% between the 2 tracer studies. Skeletal uptake of 166Ho-DOTMP varied from 19% to 39% (mean, 28%). The activity of 166Ho prescribed for therapy ranged from 38 to 67 GBq (1,030-1,810 mCi). After high-dose therapy, the estimates of absorbed dose to the kidney varied from 1.6 to 4 Gy using the whole-body clearance-based method and from 8.3 to 17.3 Gy using the ROI-based method. Bladder dose ranged from 10 to 20 Gy, bone surface dose ranged from 39 to 57 Gy, and doses to other organs were less than 2 Gy for all patients. Repetitive administration had no impact on tracer biodistribution, pharmacokinetics, or organ dose. CONCLUSION: Pharmacokinetics analysis validated gamma-camera whole-body counting of 166Ho as an appropriate approach to assess clearance and to estimate radiation-absorbed dose to normal organs except the kidneys. Quantitative gamma-camera imaging is difficult and requires scatter subtraction because of the multiple energy emissions of 166Ho. Kidney dose estimates were approximately 5-fold higher when the ROI-based method was used rather than the clearance-based model, and neither appeared reliable. In future clinical trials with 166Ho-DOTMP, we recommend that dose estimation based on the methods described here be used for all organs except the kidneys. Assumptions for the kidney dose require further evaluation. 相似文献