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911.
912.
Abstract

Currently, nanotechnology-based products are gaining tremendous interest in the development of nanocarriers for drug delivery and nano-diagnostic devices. Nanodroplets (NDs) emerge as novel carriers for delivery of gases and actives with a wide range of applications in fields of theranostics, drug delivery and diagnostic devices. NDs are multifunctional carriers composed of an outer shell of drug and polymer that encapsulates the inner core of gases and liquid molecules. This review focuses on properties of NDs, mathematical theories, different polymers used in the preparation of NDs, characterisation, animal models, toxicity and applications of NDs. These nanocarriers are advantageous due to their cost-effectiveness and compatibility with both gaseous and liquid core molecules. NDs are increasingly utilised in the field of healthcare due to their properties like large effective surface area for drug loading and target specificity. These nanocarriers are also employed in the treatment of hypoxia, multiple sclerosis and cancer. In the near future, NDs will advance in fields of personalised medicine and precise theranostics.  相似文献   
913.
The supercritical carbon dioxide-assisted extraction (SC CO2E) process was optimized for extracting picroside I and picroside II from Picrorhiza scrophulariiflora rhizomes. The picroside I and picroside II content was determined using validated LC–MS methodology. The response surface methodology (RSM) was employed to study quantitative effects of extraction parameters viz. operating pressure, temperature, modifier concentration and extraction time using Box–Behnken design. The experimental data were fitted to second-order polynomial equation using multiple regression analysis and analyzed using the appropriate statistical method. By solving the regression equation and analyzing 3D plots, the optimum extraction conditions were found to be: extraction pressure, 25 MPa; temperature, 40 °C; modifier concentration, 15 % and extraction time, 90 min. The effect of four different ionic liquids (IL) as a modifier additive has been investigated using optimized SC CO2E conditions. None of the IL showed equivalent or enhanced recovery of analytes of interest. The conventional hot percolation of P. scrophulariiflora powder resulted in 23.69 ± 1.02 and 10.22 ± 0.71 mg g?1 picroside I and II, respectively, after an extraction period of 6 h whereas SC CO2E with methanol as modifier showed 33.14 ± 1.23 and 16.77 ± 0.82 mg g?1 recovery of picroside I and II, respectively in 90 min. The comparison of yield and extraction time demonstrated that SC CO2E using methanol as modifier is more efficient than conventional hot percolation method.  相似文献   
914.
The criterion for assessing whether a drug prolongs QT as described in the International Conference on Harmonization topic E14 guideline does not explicitly account for individual drug concentrations. The authors' experience with reviewing QT studies indicates that understanding the relationship, if any, between individual drug concentration and QT change provides important additional information to support regulatory decision making. Therefore, regulatory reviews of "thorough QT" studies routinely include a characterization of the concentration-QT relationship. The authors provide examples to illustrate how the concentration-QT relationship has been used to plan and interpret the thorough QT study, to evaluate QT risk for drugs that have no thorough QT studies, to assess QT risk in subpopulations, to make dose adjustments, and to write informative drug labels.  相似文献   
915.
Complications of orthognathic surgery   总被引:1,自引:0,他引:1  
Complications in orthognathic surgery may stem from occurrences at anyone of many time points during the course of the patient's treatment: preoperative judgment and planning, perioperative orthodontic care, or intraoperatively. This article specifically addresses those complications that arise as a result of intraoperative technique. Such complications may broadly be characterized as airway, vascular, neurologic, infectious, skeletal, or aesthetic in nature. For each type, specific complications, their prevention, and their treatment are discussed.  相似文献   
916.
Arthrogryposis is the name given to a group of musculoskeletal disorders characterized by multiple joint contractures through the body that are present at birth. There are many causes for congenital limitations of the range of motion of a joint. However, the most common form of arthrogryposis, present in 40% of cases, is a condition called amyoplasia. In many cases, abnormal nerve, muscle, and connective tissue development is involved. Hands, wrists, elbows, shoulders, hips, feet, knees, back, and jaws are affected. Because of the complexity of tissue alterations and implications in normal facial growth, the authors of this article address the aspects related to clinical manifestations and therapeutic planning for patients with this condition who seek orthodontic treatment or orthognathic surgery.  相似文献   
917.
Objective: To demonstrate a strategy employed by predatory publishers to trap eager-to-publish authors or researchers into submitting their work.

Methods: This was a case study of 13 potential, possible, or probable predatory scholarly open-access publishers with similar characteristics. Eleven publishers were included from Beall’s list and two additional publishers were identified from a Google web search. Each publisher’s site was visited and its content analyzed. Publishers publishing biomedical journals were further explored and additional data was collected regarding their volumes, details of publications and editorial-board members.

Results: Overall, the look and feel of all 13 publishers was similar including names of publishers, website addresses, homepage content, homepage images, list of journals and subject areas, as if they were copied and pasted. There were discrepancies in article-processing charges within the publishers. None of the publishers identified names in their contact details and primarily included only email addresses. Author instructions were similar across all 13 publishers. Most publishers listed journals of varied subject areas including biomedical journals (12 publishers) covering different geographic locations. Most biomedical journals published none or very few articles. The highest number of articles published by any single biomedical journal was 28. Several editorial-board members were listed across more than one journals, with one member listed 81 times in different 69 journals (i.e. twice in 12 journals).

Conclusion: There was a strong reason to believe that predatory publishers may have several publication houses with different names under a single roof to trap authors from different geographic locations.  相似文献   

918.
919.
The HIV-1 accessory protein Nef is considered to play an important role in the development of a podocyte phenotype in HIV-1 associated nephropathy. We hypothesized that Nef may be altering the podocyte phenotype both structurally and functionally. To elucidate the involved mechanisms, podocyte proteins interacting with Nef were identified using GST pull down assay and yeast two hybrid assay. The GST pull down assay on protein extracts made from stable colonies of conditionally immortalized human podocytes expressing Nef (Nef/CIHP) displayed a band at 45 kD, which was identified as actin by mass spectrometry. Yeast two hybrid assay identified the following Nef-interacting proteins: syntrophin, filamin B, syntaxin, translational elongation factor 1, and zyxin. The Nef–actin and Nef–zyxin interactions were confirmed by co-localization studies on Nef/CIHP stable cell lines. The co-localization studies also showed that Nef/CIHP stable cell lines had a decreased number of actin filaments (stress fibers), displayed formation of lamellipodia, and increased number of podocyte projections (filopodia). Nef/CIHP displayed an enhanced cortical F-actin score index (P < 0.001) and thus indicated a reorganization of F-actin in the cortical regions. Microarray analysis showed that Nef enhanced the expression of Rac1, syndecan-4, Rif, and CDC42 and attenuated the expression of syndecan-3 and syntenin. In addition, Nef/CIHPs displayed a diminished sphingomyelinase (ASMase) activity. Functionally, Nef/CIHPs displayed diminished attachment and enhanced detachment to their substrate. These findings indicate that Nef interaction with actin compromises the podocyte cytoskeleton integrity.  相似文献   
920.
Tetanus is a rare life-threatening condition often complicated by repetitive spasms, dysautonomia and neuromuscular respiratory failure contributing to high fatality rates in its severe form. Benzodiazepines used to treat muscle spasms pose a high risk of respiratory failure requiring mechanical ventilation, which is unaffordable and inaccessible for many. Magnesium sulfate, a cheap and widely available medication in all urban and rural health centres of LMICs for the treatment of eclampsia, can be used to control muscle spasms and dysautonomia. We thus conducted a systematic review of evidence to assess the safety and efficacy of magnesium sulfate in the treatment of tetanus. Any study published before April 15, 2021, discussing the efficacy and/or safety of MgSO4 infusion in the treatment of tetanus was systemically reviewed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Our systematic review included data from 13 studies, three were randomised, double-blind and controlled trials. The remaining ten studies were observational; six prospective and four retrospective studies. Our review showed no mortality benefit associated with the use of magnesium sulfate. However, magnesium sulfate was found to be effective in reducing spasms along with diazepam, leading to better control of dysautonomia, reduced need for mechanical ventilation and shorter hospital stay by 3–7 days. The incidence of magnesium toxicity was very low in the studies included.  相似文献   
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