全文获取类型
收费全文 | 2635篇 |
免费 | 130篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 241篇 |
妇产科学 | 69篇 |
基础医学 | 252篇 |
口腔科学 | 55篇 |
临床医学 | 132篇 |
内科学 | 411篇 |
皮肤病学 | 57篇 |
神经病学 | 191篇 |
特种医学 | 84篇 |
外科学 | 391篇 |
综合类 | 323篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 96篇 |
眼科学 | 40篇 |
药学 | 167篇 |
1篇 | |
中国医学 | 6篇 |
肿瘤学 | 211篇 |
出版年
2022年 | 27篇 |
2021年 | 57篇 |
2020年 | 28篇 |
2019年 | 35篇 |
2018年 | 53篇 |
2017年 | 36篇 |
2016年 | 48篇 |
2015年 | 71篇 |
2014年 | 68篇 |
2013年 | 87篇 |
2012年 | 122篇 |
2011年 | 138篇 |
2010年 | 139篇 |
2009年 | 116篇 |
2008年 | 138篇 |
2007年 | 154篇 |
2006年 | 135篇 |
2005年 | 133篇 |
2004年 | 115篇 |
2003年 | 91篇 |
2002年 | 81篇 |
2001年 | 78篇 |
2000年 | 68篇 |
1999年 | 65篇 |
1998年 | 45篇 |
1997年 | 51篇 |
1996年 | 41篇 |
1995年 | 28篇 |
1994年 | 28篇 |
1993年 | 12篇 |
1992年 | 38篇 |
1991年 | 30篇 |
1990年 | 25篇 |
1989年 | 22篇 |
1988年 | 34篇 |
1987年 | 21篇 |
1986年 | 20篇 |
1985年 | 22篇 |
1984年 | 15篇 |
1983年 | 17篇 |
1982年 | 20篇 |
1981年 | 14篇 |
1978年 | 24篇 |
1977年 | 23篇 |
1976年 | 16篇 |
1975年 | 11篇 |
1974年 | 21篇 |
1973年 | 15篇 |
1972年 | 16篇 |
1970年 | 12篇 |
排序方式: 共有2770条查询结果,搜索用时 15 毫秒
91.
Gupta S Kumar N Singhal N Kaur R Manektala U 《Indian journal of pathology & microbiology》2006,49(3):457-461
To study the spectrum of vaginal microflora in postmenopausal women on hormone replacement therapy (HRT) and to compare the efficacy of Papanicolaou (Pap) smears with other methods for their detection. Eighty postmenopausal women were recruited for the study. These included 40 women who had attained spontaneous and were on HRT (User 1); 20 hysterectomised women on only estrogen therapy (User 2) and 20 controls (Non users). Their clinical data was recorded and specimens were collected for vaginal cultures (for aerobic bacteria and fungi), vaginal pH, Gram stain and Pap stain on cervical-vaginal smears and toluidine blue on wet smears. Vaginal pH was significantly lower in Users as compared to Non users. Lactobacilli and Gardnerella were more frequently isolated from Users while Bacteroides and E. coli were more common in Non users. Cultures were significantly more sensitive than Gram stained direct vaginal smears in detection of aerobic bacteria; however, Candida could be detected on Gram stain alone in all the cases. Frequency of detection of organisms significantly improved by application of Gram stain to the cervico-vaginal smears. However, clinically relevant organisms like Candida, Gardnerella and Mobiluncus could be identified on Pap smears alone in >50% cases. Lactobacilli could be readily identified in Pap smears in 98% cases. Wet mounts could detect cocci more easily as compared to Pap smears. Altered vaginal microbial profile in post menopausal women receiving HRT may cause bacterial and fungal vaginitis. Although culture studies remain the gold standard to detect these microorganisms, Pap and Gram stains and wet smears provide useful supplements and may be used as alternative procedures especially in resource limited settings lacking adequate culture facilities. 相似文献
92.
W. Taylor Kimberly Thomas W. K. Battey Ly Pham Ona Wu Albert J. Yoo Karen L. Furie Aneesh B. Singhal Jordan J. Elm Barney J. Stern Kevin N. Sheth 《Neurocritical care》2014,20(2):193-201
Background
Brain edema is a serious complication of ischemic stroke that can lead to secondary neurological deterioration and death. Glyburide is reported to prevent brain swelling in preclinical rodent models of ischemic stroke through inhibition of a non-selective channel composed of sulfonylurea receptor 1 and transient receptor potential cation channel subfamily M member 4. However, the relevance of this pathway to the development of cerebral edema in stroke patients is not known.Methods
Using a case–control design, we retrospectively assessed neuroimaging and blood markers of cytotoxic and vasogenic edema in subjects who were enrolled in the glyburide advantage in malignant edema and stroke-pilot (GAMES-Pilot) trial. We compared serial brain magnetic resonance images (MRIs) to a cohort with similar large volume infarctions. We also compared matrix metalloproteinase-9 (MMP-9) plasma level in large hemispheric stroke.Results
We report that IV glyburide was associated with T2 fluid-attenuated inversion recovery signal intensity ratio on brain MRI, diminished the lesional water diffusivity between days 1 and 2 (pseudo-normalization), and reduced blood MMP-9 level.Conclusions
Several surrogate markers of vasogenic edema appear to be reduced in the setting of IV glyburide treatment in human stroke. Verification of these potential imaging and blood biomarkers is warranted in the context of a randomized, placebo-controlled trial. 相似文献93.
Ashwini Ranade Gary J. Young Raul Garcia John Griffith Astha Singhal Jean McGuire 《Journal of the American Dental Association (1939)》2019,150(8):656-663
BackgroundInadequate access to oral health care and palliative care provided in the emergency department (ED) creates a pattern of repeat nontraumatic dental condition (NTDC) ED visits. The authors examined NTDC ED revisits and assessed the determinants associated with these visits in Massachusetts.MethodsThe authors examined NTDC ED revisits in Massachusetts during 2013 using the Massachusetts All-Payer Claims Database. The authors report patient characteristics of those who made a single NTDC ED visit and of those who made NTDC ED revisits within 30 days of the index NTDC ED visit. The authors used a multilevel logistic regression model to examine the determinants associated with NTDC ED repeat visits.ResultsIn 2013, 21.5% of NTDC ED visits were revisits. Men from 26 through 35 years of age who were enrolled in Medicaid and who did not make an outpatient dental office visit within 30 days of the index NTDC ED visit had increased odds of repeat visits.ConclusionsThe sizable proportion of NTDC ED repeat visits indicates that certain patients in Massachusetts experience consistent and systematic barriers in accessing appropriate and timely oral health care.Practical ImplicationsPrioritizing young adults and Medicaid enrollees for ED diversion programs and setting up a formal referral process via connecting patients to dental offices and community health centers after an NTDC ED visit may reduce NTDC ED revisits and provide appropriate oral health care to these patients. 相似文献
94.
Myocardial protein kinases: I. Properties of soluble and membrane-bound catalytic subunits. 总被引:1,自引:0,他引:1
The particulate fraction of rat left ventricle, under certain specific assay conditions, was found to contain as much protein phosphotransferase activity as the soluble fraction. Both the soluble and the membrane-bound holoenzyme could be activated by cyclic AMP. The properties of the catalytic subunit of the soluble enzyme differed from those of the catalytic subunit of the particulate fraction with respect to substrate specificity and apparent KM values for ATP. The soluble enzyme was found to have a very low apparent KM for ATP (5.0 × 10?6m) and was inhibited by ATP concentrations above 0.2 mm. The particulate enzyme, on the other hand, showed a high apparent KM for ATP (1.3 × 10?4m) and the activity increased with increasing ATP concentrations up to 0.4 mm. The activities in the soluble and particulate fractions were observed to vary inversely between ATP concentrations of 0.1 mm and 0.4 mm. It is concluded that ATP concentration may play a role in controlling the activity of the catalytic subunit after its dissociation from the holoenzyme (by cyclic AMP binding to the regulatory subunit). 相似文献
95.
Greer D Scripko P Bartscher J Sims J Camargo E Singhal A Parides M Furie K 《Neurocritical care》2012,17(2):240-244
Background
In clinical practice, magnetic resonance imaging (MRI) is commonly used to assess the severity of a cardiac arrest patient??s cerebral injury, utilizing treating neurologists?? imaging interpretation. We sought to determine whether clinical interpretation of diffusion-weighted imaging (DWI) helps to determine poor outcome in comatose cardiac arrest patients.Methods
We analyzed 80 consecutive MRIs from patients in coma following cardiac arrest. Each study was graded as ??normal?? or ??abnormal restricted diffusion?? in pre-specified brain regions by two blinded stroke neurologists. Poor outcome was defined as a modified Rankin Scale (mRS) score >4 at 3?months. Formal interpretations of neuroimaging by non-blinded neuroradiologists were compared with the blinded reviews by the stroke neurologists.Results
DWI abnormalities were highly sensitive (98.5?%) but only modestly specific (46.2?%) for predicting poor neurological outcome. Inter-observer reliability was moderate (kappa?=?0.49?±?0.32), with 91?% agreement between study observers, and no significant differences in study observers?? interpretations (p?=?0.125). There were, however, significant differences between the study observers and the clinical neuroradiologists in identifying studies showing evidence of global hypoxic-ischemic injury (p?=?0.001).Conclusions
The qualitative evaluation of imaging abnormalities by stroke physicians in comatose cardiac arrest patients is a highly sensitive method of predicting poor outcome, but with limited specificity. 相似文献96.
97.
98.
Surya Porwal Shikha Tewari Rajinder K. Sharma Savita Rani Singhal Satish C. Narula 《Journal of periodontology》2014,85(10):1380-1389
Background: Recently, some studies have revealed the effect of polycystic ovary syndrome (PCOS) on gingival inflammation. This cross‐sectional study attempts to assess the periodontal status and systemic inflammation of women receiving medical treatment for PCOS and women newly diagnosed with PCOS. Methods: A total of 126 participants comprising 41 newly diagnosed patients with PCOS (PCOS‐N), 45 patients with PCOS on medical treatment (PCOS‐MT), and 40 systemically healthy controls (control group [CG]) were examined. Periodontal parameters, anthropometric parameters, and serum levels of high‐sensitivity C‐reactive protein (hsCRP) were recorded. Results: Women with newly diagnosed PCOS had increased sites with bleeding on probing (BOP), probing depth, clinical attachment level (CAL), waist circumference (WC), hsCRP, and prevalence of periodontitis compared with control and PCOS‐MT groups (P ≤0.05). On partial correlation analysis after controlling for confounders, BOP and CAL correlated positively and significantly with hsCRP (P = 0.01 and P = 0.005). Multivariate linear regression analysis revealed that BOP and CAL (dependent variable) (P = 0.009/R2 = 0.05 and P = 0.005/R2 = 0.07, respectively) had significant association with hsCRP. Furthermore, hsCRP, when considered as outcome, also exhibited association with CAL and WC (P = 0.002/R2 = 0.07 and P = 0.04/R2 = 0.106). Logistic regression analysis demonstrated that the PCOS‐N group had 2.88 times increased likelihood of having moderate periodontitis (adjusted odds ratio 2.88, 95% confidence interval 1.18 to 6.98). Conclusions: Women with newly diagnosed PCOS may have increased prevalence and likelihood for periodontitis, with higher measures of periodontal inflammation and breakdown than those on medical treatment for PCOS and systemically healthy females. Furthermore, periodontal breakdown might depend on systemic inflammation and vice versa. 相似文献
99.
100.
Madhu Poornima Mamidala Anupama Polinedi Praveen Kumar P.T.V. N. Rajesh OmSai Ramesh Vallamkonda Vrajesh Udani Nidhi Singhal Vidya Rajesh 《Research in developmental disabilities》2013,34(9):3004-3013
Incidence of Autism Spectrum Disorder (ASD) is increasing across the globe and no data is available from India regarding the risk factors of ASD. In this regard a questionnaire based epidemiological assessment was carried out on prenatal, perinatal and neonatal risk factors of ASD across 8 cities in India. A retrospective cohort of 942 children was enrolled for the study. 471 children with ASD, under age of 10, were analyzed for pre-, peri-, and neonatal factors and were compared with the observations from equal number of controls. The quality control of the questionnaire and data collection was done thoroughly and the observations were computed statistically. A total of 25 factors were evaluated by unadjusted and adjusted analysis in this study. Among the prenatal factors considered, advanced maternal age, fetal distress and gestational respiratory infections were found to be associated with ASD and had an odds ratio of 1.8. Evaluation of perinatal and neonatal risk factors showed labor complications, pre-term birth, neonatal jaundice, delayed birth cry and birth asphyxia to be associated with ASD with an odds ratio greater than 1.5. This important study, first of its kind in Indian population gives a firsthand account of the relation of pre-, peri- and neonatal risk factors on ASD from an ethnically and socially diverse country like India, the impact of which was unknown earlier. This advocates additional focused investigations on physiological and genetic changes contributed by these risk factor inducing environments. 相似文献