全文获取类型
收费全文 | 805篇 |
免费 | 61篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 85篇 |
妇产科学 | 48篇 |
基础医学 | 130篇 |
口腔科学 | 11篇 |
临床医学 | 55篇 |
内科学 | 134篇 |
皮肤病学 | 27篇 |
神经病学 | 56篇 |
特种医学 | 13篇 |
外科学 | 62篇 |
综合类 | 25篇 |
预防医学 | 49篇 |
眼科学 | 19篇 |
药学 | 82篇 |
中国医学 | 7篇 |
肿瘤学 | 60篇 |
出版年
2023年 | 6篇 |
2022年 | 12篇 |
2021年 | 25篇 |
2020年 | 17篇 |
2019年 | 11篇 |
2018年 | 32篇 |
2017年 | 17篇 |
2016年 | 22篇 |
2015年 | 24篇 |
2014年 | 29篇 |
2013年 | 39篇 |
2012年 | 54篇 |
2011年 | 69篇 |
2010年 | 50篇 |
2009年 | 37篇 |
2008年 | 49篇 |
2007年 | 54篇 |
2006年 | 41篇 |
2005年 | 41篇 |
2004年 | 28篇 |
2003年 | 40篇 |
2002年 | 24篇 |
2001年 | 12篇 |
2000年 | 10篇 |
1999年 | 14篇 |
1998年 | 12篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1984年 | 6篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 7篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1973年 | 3篇 |
1971年 | 2篇 |
1969年 | 2篇 |
1968年 | 4篇 |
1965年 | 5篇 |
1962年 | 2篇 |
排序方式: 共有866条查询结果,搜索用时 0 毫秒
141.
Indu Singh Rajan Swami Deep Pooja Manish Kumar Jeengar 《Journal of drug targeting》2016,24(3):212-223
Background: Delivery of drugs to brain is a subtle task in the therapy of many severe neurological disorders. Solid lipid nanoparticles (SLN) easily diffuse the blood–brain barrier (BBB) due to their lipophilic nature. Furthermore, ligand conjugation on SLN surface enhances the targeting efficiency. Lactoferin (Lf) conjugated SLN system is first time attempted for effective brain targeting in this study.Purpose: Preparation of Lf-modified docetaxel (DTX)-loaded SLN for proficient delivery of DTX to brain.Methods: DTX-loaded SLN were prepared using emulsification and solvent evaporation method and conjugation of Lf on SLN surface (C-SLN) was attained through carbodiimide chemistry. These lipidic nanoparticles were evaluated by DLS, AFM, FTIR, XRD techniques and in vitro release studies. Colloidal stability study was performed in biologically simulated environment (normal saline and serum). These lipidic nanoparticles were further evaluated for its targeting mechanism for uptake in brain tumour cells and brain via receptor saturation studies and distribution studies in brain, respectively.Results: Particle size of lipidic nanoparticles was found to be optimum. Surface morphology (zeta potential, AFM) and surface chemistry (FTIR) confirmed conjugation of Lf on SLN surface. Cytotoxicity studies revealed augmented apoptotic activity of C-SLN than SLN and DTX. Enhanced cytotoxicity was demonstrated by receptor saturation and uptake studies. Brain concentration of DTX was elevated significantly with C-SLN than marketed formulation.Conclusions: It is evident from the cytotoxicity, uptake that SLN has potential to deliver drug to brain than marketed formulation but conjugating Lf on SLN surface (C-SLN) further increased the targeting potential for brain tumour. Moreover, brain distribution studies corroborated the use of C-SLN as a viable vehicle to target drug to brain. Hence, C-SLN was demonstrated to be a promising DTX delivery system to brain as it possessed remarkable biocompatibility, stability and efficacy than other reported delivery systems. 相似文献
142.
Preeti Kumari Muddineti Omkara Swami Sravan Kumar Nadipalli Srividya Myneni Balaram Ghosh Swati Biswas 《Pharmaceutical research》2016,33(4):826-841
Purpose
This work describes the synthesis of block co-polymeric micelles, methoxy-poly(ethylene glycol)-poly(D,L-lactide) (mPEG-PLA) to encapsulate Curcumin (CUR), thereby improving the dispersibility and chemical stability of curcumin, prolonging its cellular uptake and enhancing its bioavailability.Methods
CUR-mPEG-PLA micelles, was prepared using the thin-film hydration method and evaluated in vitro. The preparation process was optimized with a central composite design (CCD). Micelles were characterized by size, transmission electron microscopy, loading capacity, and critical micelle concentration (CMC). The cytotoxicity of CUR-mPEG-PLA micelles was investigated against murine melanoma cells, B16F10 and human breast cancer cells, MDA-MB-231.Results
The average size of the CUR-mPEG-PLA micelles was 110?±?5 nm with polydispersity index in the range of 0.15–0.31, and the encapsulating efficiency for CUR was 91.89?±?1.2, and 11.06?±?0.8% for drug-loading. Sustained release of CUR from micelles was observed with 9.73% CUR release from micelles compared to 64.24% release of free curcumin in first 6 h under sink condition. The CUR-mPEG-PLA was efficiently taken up by the cancer cells, B16F10 and MDA-MB-231. Following 24 h incubation, CUR-mPEG-PLA induced higher cytotoxicity compared to free CUR in MDA-MB-231 cell lines indicating exposure of higher dose of free CUR to cells lead to up-regulation of drug efflux mechanisms leading to decreased cell death in case of free CUR administration.Conclusion
Our results indicate that the proposed micellar system has the potential to serve as an efficient carrier for CUR by effectively solubilizing, stabilizing and delivering the drug in a controlled manner to the cancer cells.143.
144.
Annalisa Dalzini Giovanni Ballin Sara DominguezRodriguez Pablo Rojo Maria Raffaella Petrara Caroline Foster Nicola Cotugno Alessandra Ruggiero Eleni Nastouli Nigel Klein Stefano Rinaldi Savita Pahwa Paolo Rossi Carlo Giaquinto Paolo Palma Anita De Rossi EPIICAL Consortium 《Journal of the International AIDS Society》2021,24(11)
IntroductionPersistence of HIV‐1, causing chronic immune activation, is a key determinant of premature senescence. Early antiretroviral therapy (ART) has been associated with a reduced HIV‐1 reservoir in children with perinatally acquired HIV‐1 (PHIV), but its impact on the senescence process is an open question. We investigated the association between HIV‐1 reservoir and biological and immune ageing profile in PHIV enrolled in the multicentre cross‐sectional study CARMA (Child and Adolescent Reservoir Measurements on early suppressive ART) conducted within the EPIICAL (Early treated Perinatally HIV Infected individuals: Improving Children''s Actual Life) consortium.MethodsBetween September 2017 and June 2018, CARMA enrolled 40 PHIV who started ART before 2 years of age and had undetectable viremia for at least 5 years before sampling date. Samples from 37 children with a median age of 13.8 years were available for this study. HIV‐1 DNA copies on CD4 cells, relative telomere length (marker of cellular senescence) and levels of T‐cell receptor rearrangement excision circle (TREC, marker of thymic output) on CD4 and CD8 cells were quantified by qPCR. Immunological profile was assessed by flow cytometry. Associations between molecular and phenotypic markers, HIV‐1 reservoir and age at ART initiation were explored using a multivariable Poisson regression.ResultsHigher HIV‐1 reservoir was associated (p<0.001) with telomere shortening (incidence rate ratio [IRR] = 0.15 [0.13–0.17]), immunosenescence (CD28–CD57+, IRR = 1.23 [1.21–1.26]) and immunoactivation (CD38+ HLADR+, IRR = 7.29 [6.58–8.09]) of CD4 cells. Late ART initiation (after 6 months of age) correlated with higher HIV‐1 reservoir levels (552 [303–1001] vs. 89 [56–365] copies/106 CD4 cells, p = 0.003) and percentage of CD4 senescent cells (2.89 [1.95–6.31] vs. 1.02 [0.45–2.69, p = 0.047). TREC levels in CD8 cells were inversely associated with HIV‐1 reservoir (IRR = 0.77 [0.76–0.79]) and were significantly lower in late treated PHIV (1128 [486–1671] vs. 2278 [1425–3314], p = 0.042).ConclusionsLater ART initiation is associated with higher HIV‐1 reservoir size, which correlates with increased telomere shortening and senescence of CD4 cells. Timing of ART initiation in infancy has long‐term consequences on the immune and biological ageing profile of children with perinatally acquired HIV‐1. 相似文献
145.
Gaurav Prakash Pankaj Malhotra Alka Khadwal Deepesh Lad Vikas Suri Savita Kumari Subhash Varma 《Indian journal of hematology & blood transfusion》2018,34(2):273-277
There is paucity of data on infusion related hypersensitivity reactions (IRHR) pattern of bio-similar rituximab in B-cell lymphoma patients. As bio-similar molecules are independently developed monoclonal antibodies, they are likely to differ in immunogenicity and therefore, the hypersensitivity data of the innovator rituximab may not be directly applicable to patients treated with the biosimilar rituximab molecule. We analysed our data of 256 patients of B cell lymphoid neoplasm who received bio-similar rituximab (Reditux) based chemo-immunotherapy for their treatment. Total 56/256 (21.8%) patients had ≥ grade II IRHR with first dose of rituximab. Grade II reactions were seen in 32/256 (12.5%) cases, grade III and grade IV reactions were seen in 21/256 (8.2%) and 3/256 (1.2%) cases, respectively. Rituximab was withdrawn from all further therapy in only 2 patients due to grade IV IRHR after attempting re-challenge of the drug under intensive monitoring. There was no difference in complete response rates in patients with or without IRHR during their first rituximab infusion. The IRHRs with bio-similar rituximab noted in our study were comparable with the previously published reactions associated with the original rituximab. 相似文献
146.
147.
Arnaud F Scultetus AH Kim B Haque A Saha B Nigam S Moon-Massat P Auker C McCarron R Freilich D 《Artificial cells, blood substitutes, and immobilization biotechnology》2011,39(4):195-205
Sodium nitrite (NaNO(2)) was evaluated in a 55% EBV hemorrhage swine model to mitigate the increased blood pressure due to HBOC-201. Animals were resuscitated by three 10 ml/kg infusions of either HBOC-201 or Hextend with and without NaNO(2). All vital signs, coagulation and blood chemistry were measured for 2 hr. HBOC-201-vasoconstriction was attenuated only after the first 10.8 μmol/kg NaNO(2) infusion. Complete abolition was obtained with the highest 3 NaNO(2) dose, but side effects were observed. There was no reduction in platelet function due to NaNO(2). NaNO(2) ability to reduce HBOC-201 vasoactivity was transient and 10.8 μmol/kg NaNO(2) seems an acceptable dose for further investigation. 相似文献
148.
This work rests on our previous report (J Cereb Blood Flow Metab 30: 1275-1287, 2010) recognizing that glutamate (Glu) oxaloacetate transaminase (GOT) is induced when brain tissue hypoxia is corrected during acute ischemic stroke (AIS). GOT can metabolize Glu into tricarboxylic acid cycle intermediates and may therefore be useful to harness excess neurotoxic extracellular Glu during AIS as a metabolic substrate. We report that in cultured neural cells challenged with hypoglycemia, extracellular Glu can support cell survival as long as there is sufficient oxygenation. This effect is abrogated by GOT knockdown. In a rodent model of AIS, supplemental oxygen (100% O(2) inhaled) during ischemia significantly increased GOT expression and activity in the stroke-affected brain tissue and prevented loss of ATP. Biochemical analyses and in vivo magnetic resonance spectroscopy during stroke demonstrated that such elevated GOT decreased Glu levels at the stroke-affected site. In vivo lentiviral gene delivery of GOT minimized lesion volume, whereas GOT knockdown worsened stroke outcomes. Thus, brain tissue GOT emerges as a novel target in managing stroke outcomes. This work demonstrates that correction of hypoxia during AIS can help clear extracellular neurotoxic Glu by enabling utilization of this amino acid as a metabolic fuel to support survival of the hypoglycemic brain tissue. Strategies to mitigate extracellular Glu-mediated neurodegeneration via blocking receptor-mediated excitotoxicity have failed in clinical trials. We introduce the concept that under hypoglycemic conditions extracellular Glu can be transformed from a neurotoxin to a survival factor by GOT, provided there is sufficient oxygen to sustain cellular respiration. 相似文献
149.
Camilla Zimmermann Debika Burman Nadia Swami Monika K. Krzyzanowska Natasha Leighl Malcolm Moore Gary Rodin Ian Tannock 《Supportive care in cancer》2011,19(5):621-629
Purpose
Improving health-related quality of life (HRQL) is the main goal of palliative care and an important outcome for oncology trials. This study examines medical and sociodemographic determinants of HRQL in outpatients with advanced cancer. 相似文献150.
Alzheimer's disease (AD) is characterized by deposition of amyloid-β (Aβ) plaques within the brain parenchyma followed by synaptic loss and neuronal death. Deposited Aβ reacts with activated microglia to produce reactive oxygen species (ROS) and cytochemokines, which lead to severe neuroinflammation. Curcumin is a yellow polyphenol compound found in turmeric, a widely used culinary ingredient that possesses anti-inflammatory and anti-cancer properties and may show efficacy as a potential therapeutic agent in several neuro-inflammatory diseases including AD. However, poor aqueous solubility and sub-optimal systemic absorption from the gastrointestinal tract may represent factors contributing to its failure in clinical trials. To increase curcumin's bioavailability, a polymeric nanoparticle encapsulated curcumin (NanoCurc?) was formulated which is completely water soluble. NanoCurc? treatment protects neuronally differentiated human SK-N-SH cells from ROS (H2O2) mediated insults. NanoCurc? also rescues differentiated human SK-N-SH cells, which were previously insulted with H2O2. In vivo, intraperitoneal (IP) NanoCurc? injection at a dose of 25mg/kg twice daily in athymic mice resulted in significant curcumin levels in the brain (0.32 μg/g). Biochemical study of NanoCurc?-treated athymic mice revealed decreased levels of H2O2 as well as caspase 3 and caspase 7 activities in the brain, accompanied by increased glutathione (GSH) concentrations. Increased free to oxidized glutathione (GSH:GSSH) ratio in athymic mice brain versus controls also indicated a favorable redox intracellular environment. Taken together, these results suggest that NanoCurc? represents an optimized formulation worthy of assessing the therapeutic value of curcumin in AD. 相似文献