全文获取类型
收费全文 | 1107篇 |
免费 | 76篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 38篇 |
妇产科学 | 10篇 |
基础医学 | 96篇 |
口腔科学 | 29篇 |
临床医学 | 107篇 |
内科学 | 276篇 |
皮肤病学 | 8篇 |
神经病学 | 78篇 |
特种医学 | 41篇 |
外科学 | 207篇 |
综合类 | 12篇 |
一般理论 | 1篇 |
预防医学 | 42篇 |
眼科学 | 29篇 |
药学 | 107篇 |
中国医学 | 2篇 |
肿瘤学 | 88篇 |
出版年
2024年 | 4篇 |
2023年 | 16篇 |
2022年 | 46篇 |
2021年 | 96篇 |
2020年 | 55篇 |
2019年 | 60篇 |
2018年 | 72篇 |
2017年 | 43篇 |
2016年 | 47篇 |
2015年 | 53篇 |
2014年 | 64篇 |
2013年 | 74篇 |
2012年 | 111篇 |
2011年 | 98篇 |
2010年 | 46篇 |
2009年 | 33篇 |
2008年 | 52篇 |
2007年 | 55篇 |
2006年 | 47篇 |
2005年 | 38篇 |
2004年 | 28篇 |
2003年 | 20篇 |
2002年 | 15篇 |
2001年 | 3篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1983年 | 1篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有1191条查询结果,搜索用时 15 毫秒
51.
Sreekanth Thota Srujana Vallala Rajeshwar Yerra Daniel Alencar Rodrigues Eliezer J. Barreiro 《Medicinal chemistry research》2016,25(10):2127-2132
The synthesis and characterization of ruthenium complexes (Ru-1–Ru-6) of the type [Ru(R)2(K)]2+ (where R?=?1,10-phenanthroline/2,2′-bipyridyl and K?=?acetyl coumarin-inh, pyrazole-tch, acetyl coumarin-tsz, are described. These ligands form bidentate octahedral ruthenium complexes. The in vitro cytotoxic activities of the complexes measurement against the human cancer T-lymphocyte cell lines. In vitro evaluation of these title complexes revealed cytotoxicity from 0.34 to 1.4?µg/mL against CEM, 0.28 to 1.8?µg/mL against L1210, 0.44 to 2.5?µg/mL against Molt4/C8, 0.98 to 1.6?µg/mL against HL60, and 0.66 to 1.4?µg/mL against BEL7402. Ruthenium complexes Ru-5 & Ru-6 showed that quite significant anticancer activities over standard drugs. 相似文献
52.
Nour Hamade Sreekar Vennelaganti Sravanthi Parasa Prashanth Vennalaganti Srinivas Gaddam Manon C.W. Spaander Sophie H. van Olphen Prashanthi N. Thota Kevin F. Kennedy Marco J. Bruno John J. Vargo Sharad Mathur Brooks D. Cash Richard Sampliner Neil Gupta Gary W. Falk Ajay Bansal Patrick E. Young Prateek Sharma 《Clinical gastroenterology and hepatology》2019,17(5):864-868
53.
Gopal A Luo Z Lee JY Kumar K Li B Hoshino K Schmidt C Ho PS Zhang X 《Biomedical microdevices》2008,10(5):611-622
We designed and fabricated silicon probe with nanophotonic force sensor to directly stimulate neurons (PC12) and measured its effect on neurite initiation and elongation. A single-layer pitch-variable diffractive nanogratings was fabricated on silicon nitride probe using e-beam lithography, reactive ion etching and wet-etching techniques. The nanogratings consist of flexure folding beams suspended between two parallel cantilevers of known stiffness. The probe displacement, therefore the force, can be measured through grating transmission spectrum. We measured the mechanical membrane characteristics of PC12 cells using the force sensors with displacement range of 10 mum and force sensitivity 8 muN/mum. Young's moduli of 425 +/- 30 Pa are measured with membrane deflection of 1% for PC12 cells cultured on polydimethylsiloxane (PDMS) substrate coated with collagen or laminin in Ham's F-12K medium. In a series of measurements, we have also observed stimulation of directed neurite contraction up to 6 mum on extended probing for a time period of 30 min. This method is applicable to measure central neurons mechanics under subtle tensions for studies on development and morphogenesis. The close synergy between the nano-photonic measurements and neurological verification can improve our understanding of the effect of external conditions on the mechanical properties of cells during growth and differentiation. 相似文献
54.
PSGL‐1 and E/P‐selectins are essential for T‐cell rolling in inflamed CNS microvessels but dispensable for initiation of EAE 下载免费PDF全文
Karthik Sathiyanadan Caroline Coisne Gaby Enzmann Urban Deutsch Britta Engelhardt 《European journal of immunology》2014,44(8):2287-2294
T‐cell migration across the blood‐brain barrier is a crucial step in the pathogenesis of EAE, an animal model for MS. Live cell imaging studies demonstrated that P‐selectin glycoprotein ligand‐1 (PSGL‐1) and its endothelial ligands E‐ and P‐selectin mediate the initial rolling of T cells in brain vessels during EAE. As functional absence of PSGL‐1 or E/P‐selectins does not result in ameliorated EAE, we speculated that T‐cell entry into the spinal cord is independent of PSGL‐1 and E/P‐selectin. Performing intravital microscopy, we observed the interaction of WT or PSGL‐1?/? proteolipid protein‐specific T cells in inflamed spinal cord microvessels of WT or E/P‐selectin?/? SJL/J mice during EAE. T‐cell rolling but not T‐cell capture was completely abrogated in the absence of either PSGL‐1 or E‐ and P‐selectin, resulting in a significantly reduced number of T cells able to firmly adhere in the inflamed spinal cord microvessels, but did not lead to reduced T‐cell invasion into the CNS parenchyma. Thus, PSGL‐1 interaction with E/P‐selectin is essential for T‐cell rolling in inflamed spinal cord microvessels during EAE. Taken together with previous observations, our findings show that T‐cell rolling is not required for successful T‐cell entry into the CNS and initiation of EAE. 相似文献
55.
56.
Sri Dantuluri Arun Urs Sivaramakrishnan Venkatesh Karthik 《Pediatric transplantation》2012,16(8):E372-E374
Dantuluri S, Urs A, Karthik SV. Follicular carcinoma of thyroid following successful liver transplantation – A report. Abstract: Follicular carcinoma of the thyroid is a relatively rare malignancy in childhood even in paediatric solid organ transplant recipients. The risk of developing de novo malignancies after liver transplantation is higher compared to the general population. We report an 18‐yr‐old girl who had successfully undergone liver transplantation five yr earlier for neonatal sclerosing cholangitis complicated by the development of dysplastic nodules. Baseline immunosuppression was with tacrolimus and prednisolone. Mycophenolate mofetil was later added in view of steroid‐resistant episodes of graft rejection. She subsequently suffered from marked obesity and essential hypertension needing antihypertensive medication. Five yr after liver transplantation, she presented with a right‐sided thyroid swelling that was rapidly progressive with no associated lymphadenopathy and normal systemic examination. Ultrasound of her neck revealed a solid lesion in the right lobe of the thyroid gland with ill‐defined margins, and a diagnostic right thyroid lobectomy confirmed the diagnosis of follicular carcinoma with focal capsular and vascular invasion. She underwent total thyroidectomy and currently remains well on thyroxine supplements. Our report highlights the need for high level of suspicion and prompt investigation into any abnormal lesion in the long‐term follow‐up of solid organ transplant recipients. 相似文献
57.
Balasubramanian K Kumar P Saini SS Attri SV Dutta S 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(3):236-241
Aim: To compare the incidence of hyponatremia in full‐term neonates with severe hyperbilirubinemia, receiving intravenous fluid supplementation with 0.2% saline in 5% dextrose versus 0.9% saline in 5% dextrose, to prevent blood exchange transfusion (BET). Methods: In this double‐blind, randomized, controlled trial, full ‐ term newborns (≥37 weeks), appropriate for gestational age, with severe non‐haemolytic hyperbilirubinemia (serum bilirubin ≥ 20 mg/dL) were enrolled. Eligible neonates were randomized to receive either 0.2% saline in 5% dextrose (hypotonic fluid group) or 0.9% saline in 5% dextrose (isotonic fluid group) over 8 hrs, in addition to phototherapy. The primary outcome was proportion of neonates developing hyponatremia (serum Na < 135 mmol/L) after 8 h. Results: Forty‐two neonates were analysed in each group. Proportion of neonates developing hyponatremia after 8 h was higher in hypotonic fluid group as compared to isotonic fluid group (48.8% vs. 10.5%, p < 0.001). However, a larger proportion in isotonic fluid group developed hypernatremia (39.5% vs. 12.2%, p < 0.001). The rate of BET was similar in both groups. Conclusion: In full‐term neonates with severe hyperbilirubinemia, administration of hypotonic fluid to prevent BET was associated with a higher incidence of hyponatremia while isotonic fluid was associated with an increased incidence of hypernatremia. 相似文献
58.
Introduction:
Under treatment of pain is a recognized global issue. Opioid analgesic medication is the mainstay of treatment in cancer patients as per the World Health Organization (WHO) pain relief ladder, yet 50% of cancer patients worldwide do not receive adequate pain relief or are undertreated.Aim:
The aim of this study was to audit the ongoing opioid-prescribing practices in our tertiary cancer pain clinic during January–June 2010.Materials & Methods:
The prescribed type of opioid, dose, dosing interval, and laxatives details were analyzed.Results:
Five hundred pain files were reviewed and 435 were found complete for audit. Three hundred forty-eight (80%) patients were prescribed opioids. Two hundred fifty-nine (74.4%) received weak opioids while 118 (33.9%) received strong opioids. A total of 195 (45%) patients had moderate and 184 (42%) had severe pain. Ninety-three (26.7%) patients received morphine; however, only 31.5% (58 of 184) in severe pain received morphine as per the WHO pain ladder. Only 73 of 93 (78.4%) patients received an adequate dose of morphine with an adequate dosing interval and only 27 (29%) were prescribed laxatives with morphine.Conclusion:
This study shows that the under treatment of pain and under dosing of opioids coupled with improper side effect management are major issues. 相似文献59.
Karthik Loganathan Gaurav Kumar Arivarasan Vishnu Kirthi Kokati Venkata Bhaskara Rao Abdul Abdul Rahuman 《Parasitology research》2013,112(11):3951-3959
A novel approach to control strategies for integrated blood-feeding parasite management is in high demand, including the use of biological control agents. The present study aims to determine the efficacy of optimized crude extract of actinomycetes strain LK1 as biological control agent against the fourth-instar larvae of Anopheles stephensi and Culex tritaeniorhynchus (Diptera: Culicidae) and adults of Haemaphysalis bispinosa, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae), and Hippobosca maculata (Diptera: Hippoboscidae). Antiparasitic activity was optimized using the Plackett–Burman method, and the design was developed using the software Design-Expert version 8.0.7.1. The production of the optimized crude actinomycetes LK1 strain extract was performed using response surface methodology to optimize the process parameters of protease inhibitor activity of marine actinobacteria for the independent variables like pH, temperature, glucose, casein, and NaCl at two levels (?1 and +1). The potential actinomycetes strain was identified as Saccharomonas spp., and the metamodeling surface simulation procedure was followed. It was studied using a computer-generated experimental design, automatic control of simulation experiments, and sequential optimization of the metamodels fitted to a simulation response surface function. The central composite design (CCD) used for the analysis of treatment showed that a second-order polynomial regression model was in good agreement with the experimental results at R 2?=?0.9829 (p?<?0.05). The optimized values of the variables for antioxidant production were pH 6.00, glucose 1.3 %, casein 0.09 %, temperature 31.23 °C, and NaCl 0.10 %. The LK1 strain-optimized crude extract was purified using reversed-phase high-pressure liquid chromatography, and the isolated protease inhibitor showed antiparasitic activity. The antiparasitic activity of optimized crude extract of LK1 was tested against larvae of A. stephensi (LC50?=?31.82 ppm; r 2?=?0.818) and C. tritaeniorhynchus (LC50?=?26.62 ppm; r 2?=?0.790) and adults of H. bispinosa (LC50?=?106.58 ppm; r 2?=?0.871), R. (B.) microplus (LC50?=?92.96 ppm; r 2?=?0.913), and H. maculata (LC50?=?84.90 ppm; r 2?=?0.857). 相似文献
60.
The purpose of the present study was to assess the effect of crude extracts of marine actinobacteria on larvicidal, repellent,
and ovicidal activities against Culex tritaeniorhynchus and Culex gelidus (Diptera: Culicidae). The early fourth instar larvae of C. tritaeniorhynchus and C. gelidus, reared in the laboratory, were used for larvicidal, ovicidal, and repellent assay with crude extracts of actinobacteria.
Saccharomonospora spp. (LK-1), Streptomyces roseiscleroticus (LK-2), and Streptomyces gedanensis (LK-3) were identified as potential biocide producers. Based on the antimicrobial activity, three strains were chosen for
larvicidal activity. The marine actinobacterial extracts showed moderate to high larvicidal effects after 24 h of exposure
at 1,000 ppm and the highest larval mortality was found in extract of LK-3 (LC50 = 108.08 ppm and LC90 = 609.15 ppm) against the larvae of C. gelidus and (LC50 = 146.24 ppm and LC90 = 762.69 ppm) against the larvae of C. tritaeniorhynchus. Complete protections for 240 min were found in crude extract of LK-2 and LK-3 at 1,000 ppm, against mosquito bites of C. tritaeniorhynchus and C. gelidus, respectively. After 24-h treatment, mean percent hatchability of the ovicidal activity was observed. The percent hatchability
was inversely proportional to the concentration of extract and directly proportional to the eggs. Crude extracts of LK-1 and
LK-3 showed no hatchability at 1,000 ppm against C. tritaeniorhynchus and C. gelidus, respectively. This is an ideal ecofriendly approach for the control of Japanese encephalitis vectors, C. tritaeniorhynchus and C. gelidus. 相似文献