全文获取类型
收费全文 | 468篇 |
免费 | 28篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 25篇 |
妇产科学 | 32篇 |
基础医学 | 49篇 |
口腔科学 | 12篇 |
临床医学 | 25篇 |
内科学 | 109篇 |
皮肤病学 | 6篇 |
神经病学 | 24篇 |
特种医学 | 9篇 |
外科学 | 78篇 |
综合类 | 13篇 |
预防医学 | 36篇 |
眼科学 | 5篇 |
药学 | 29篇 |
中国医学 | 5篇 |
肿瘤学 | 38篇 |
出版年
2023年 | 3篇 |
2022年 | 8篇 |
2021年 | 16篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 15篇 |
2017年 | 6篇 |
2016年 | 12篇 |
2015年 | 15篇 |
2014年 | 18篇 |
2013年 | 24篇 |
2012年 | 37篇 |
2011年 | 48篇 |
2010年 | 23篇 |
2009年 | 28篇 |
2008年 | 41篇 |
2007年 | 38篇 |
2006年 | 30篇 |
2005年 | 31篇 |
2004年 | 25篇 |
2003年 | 21篇 |
2002年 | 12篇 |
2001年 | 5篇 |
2000年 | 5篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1991年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1971年 | 2篇 |
1946年 | 1篇 |
1945年 | 1篇 |
排序方式: 共有498条查询结果,搜索用时 203 毫秒
81.
Wig J Chandrashekharappa KN Yaddanapudi LN Nakra D Mukherjee KK 《Journal of neurosurgical anesthesiology》2007,19(4):239-242
The exact incidence of postoperative nausea and vomiting (PONV) in patients on steroids undergoing neurosurgical procedures is not known. This prospective randomized double-blind study was planned to know the efficacy of prophylactic ondansetron in the prevention of PONV in patients on steroids as compared with placebo. Seventy adult patients of either sex who had received preoperative steroids (dexamethasone) for at least 24 hours and were scheduled to undergo craniotomy for supratentorial tumors were included. Patients were randomly allocated using a randomization chart to 1 of the 2 groups to receive either ondansetron 4 mg (group O) or 0.9% saline (group S) intravenously at the time of dural closure. Numeric Rating Scale score for nausea and pain intensity was recorded preoperatively and till 24 hours postoperatively. The 6-hour postoperative nausea score was significantly lower in group O [median, 0; interquartile range (IQR), 0 to 20] than in group S (median, 20; IQR, 0 to 20) (P<0.05). The incidence of vomiting was lower in group O (23%) than in group S (46%) (P<0.05). The total number of emetic episodes, the number of doses of rescue antiemetics given in the first 6 postoperative hours, and the total number of rescue antiemetics given were significantly lower in group O than in group S (P<0.05). Intravenous administration of 4 mg of ondansetron at the time of dural closure was effective in reducing the incidence of PONV and the rescue antiemetics requirement in patients on preoperative steroids undergoing craniotomy for supratentorial tumors. 相似文献
82.
Punj J Pandey R Darlong V 《International Journal of Obstetric Anesthesia》2007,16(4):388-9; author reply 389
83.
Sen J Godara R Singh R Airon RK 《Asian journal of surgery / Asian Surgical Association》2007,30(2):122-125
BACKGROUND: Erectile dysfunction is a common and potentially treatable problem. Other than psychological, anatomical and metabolic factors, vasculogenic causes also play an important role in erectile dysfunction. Among the various diagnostic tools available for the diagnosis of vasculogenic causes, colour Doppler sonography is noninvasive, simple and promising. METHODS: This preliminary prospective study was conducted on 40 patients with erectile dysfunction, coming from a rural background to a hospital situated in a semi-urban setting. RESULTS: It was found that a cut-off value of 10 cm/second for peak systolic velocity in flaccid penis had the best accuracy among three chosen cut-off values, i.e. 5, 10, 15 cm/second, for detecting arterial insufficiency with sensitivity of 94.1%, specificity of 93.6%, negative predictive value of 98% and positive predictive value of 80%. CONCLUSION: Doppler sonography may be used as a good predictor of clinical response to intracavernosal injection of a vasodilating pharmacological agent. 相似文献
84.
85.
Zeba Khanam Pratima Mittal Jyotsna Suri 《Journal of obstetrics and gynaecology of India》2021,71(3):226
Purpose of StudyTo study the role of uterine artery Doppler pulsatility index (UtA-PI), serum pregnancy-associated plasma protein-A (PAPP-A) and free beta human chorionic gonadotropin (fβ-hCG) levels, individually and in combination with each other, at 11–14 weeks of gestation for prediction of preeclampsia (PE).MethodsIn a prospective observational study, a total of 100 low-risk gravid females were recruited at 11–14-weeks of gestation. UtA-PI, PAPP-A and fβ-hCG levels were estimated. These women were followed up until delivery for the development of PE and gestational hypertension (GH).ResultsThe best individual marker for screening PE and GH was UtA-PI with ROC AUC (± standard error) = 0.934 ± 0.028, p < 0.0001. UtA-PI at a cutoff value of ≥ 2.8 (95th percentile) had 77.8% sensitivity, 98.9% specificity, 97.8% NPV and 87.5% PPV in detecting PE. PAPP-A (MoM) at a cutoff value of ≤ 0.27 (5th percentile) demonstrated 44.4% sensitivity, 95.6% specificity, 94.5% NPV and 50% PPV. fβ-hCG (MoM) at a cutoff value of ≤ 0.5 (5th percentile) had a specificity of 94.5%. Among the combined markers, UtA-PI along with PAPP-A estimation served best with a sensitivity and specificity of 44% and 100%, respectively. Addition of fβ-hCG to either UtA-PI or PAPP-A levels was not found sensitive for detecting PE but yielded 100% specificity and 96% NPV.ConclusionUtA-PI as a stand-alone test was found most useful for the prediction of PE. Addition of either or both of PAPP-A and fβ-hCG to UtA-PI did not improve the sensitivity of combined test with only a slight improvement in specificity and NPV. Their routine addition to UtA-PI studies is not recommended for prediction of PE at 11–14 weeks of gestation in low- and lower-middle-income countries (LMIC). 相似文献
86.
87.
Recurrent 16p11.2 microdeletions in autism 总被引:6,自引:0,他引:6
Kumar RA KaraMohamed S Sudi J Conrad DF Brune C Badner JA Gilliam TC Nowak NJ Cook EH Dobyns WB Christian SL 《Human molecular genetics》2008,17(4):628-638
Autism is a childhood neurodevelopmental disorder with a strong genetic component, yet the identification of autism susceptibility loci remains elusive. We investigated 180 autism probands and 372 control subjects by array comparative genomic hybridization (aCGH) using a 19K whole-genome tiling path bacterial artificial chromosome microarray to identify submicroscopic chromosomal rearrangements specific to autism. We discovered a recurrent 16p11.2 microdeletion in two probands with autism and none in controls. The deletion spans approximately 500-kb and is flanked by approximately 147-kb segmental duplications (SDs) that are >99% identical, a common characteristic of genomic disorders. We assessed the frequency of this new autism genomic disorder by screening an additional 532 probands and 465 controls by quantitative PCR and identified two more patients but no controls with the microdeletion, indicating a combined frequency of 0.6% (4/712 autism versus 0/837 controls; Fisher exact test P = 0.044). We confirmed all 16p11.2 deletions using fluorescence in situ hybridization, microsatellite analyses and aCGH, and mapped the approximate deletion breakpoints to the edges of the flanking SDs using a custom-designed high-density oligonucleotide microarray. Bioinformatic analysis localized 12 of the 25 genes within the microdeletion to nodes in one interaction network. We performed phenotype analyses and found no striking features that distinguish patients with the 16p11.2 microdeletion as a distinct autism subtype. Our work reports the first frequency, breakpoint, bioinformatic and phenotypic analyses of a de novo 16p11.2 microdeletion that represents one of the most common recurrent genomic disorders associated with autism to date. 相似文献
88.
89.
90.
Prachi Srivastava Smriti Badhwar Dinu S. Chandran Ashok Kumar Jaryal Viveka P. Jyotsna Kishore Kumar Deepak 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2019,13(3):2061-2068
AimDiabetes is associated with Renin-angiotensin-aldosterone-system (RAAS) activation. Protective role of Angiotensin (1-7) has been recently identified. The study aims to identify associations between imbalance in RAAS components with vascular endothelial dysfunction and inflammation in diabetics with newly diagnosed hypertension.MethodsBrachial Flow-mediated-dilation (FMD), Carotid Intima-media-thickness (CIMT), pulse-wave-velocity (PWV), Serum E-selectin, Vascular-Cell-Adhesion-Molecule-1 (VCAM-1), high-sensitivity C-Reactive Protein (hsCRP), Interleukin-10 (IL-10), Renin, AngiotensinII, Angiotensin-Converting-Enzyme 2 (ACE2) and Angiotensin1-7 were measured in 60 diabetic patients with newly diagnosed hypertension. Patients with AngiotensinII/Angiotensin1-7 ratio <1 were classified as Favourable-Axis (FA) group (n = 22) and those with ratio >1 were classified as Unfavourable-Axis (UA) group (n = 38).ResultshsCRP was higher [9.52 (4.64–16.19) vs 3.62 (1.77–13.09) (mg/l), p = 0.04], IL-10 was lower [2.26 (1.34–12.05) vs 10.98 (4.44–17.78) (pg/ml),p = 0.006], %FMD was lower [(5.51 ± 2.97) vs (7.66 ± 3.38) (%), p = 0.01] and CIMT was higher in UA compared to FA group [0.7 (0.55–0.79) vs 0.51 (0.49–0.65) (mm), p = 0.001]. Renin correlated positively with pressure, PWV, E-selectin and VCAM-1, opposing associations were obtained for Angiotensin1-7 and ACE2.ConclusionImbalance between AngiotensinII – Angiotensin1-7 is associated with increased inflammation and vascular dysfunction in diabetics and can contribute to development of hypertension in these patients. 相似文献