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991.
Céline Cavézian Isabelle Gaudry Céline Perez Olivier Coubard Gaëlle Doucet Christian Marendaz Olivier Gout Sylvie Chokron 《Cortex; a journal devoted to the study of the nervous system and behavior》2010,46(9):1123-1131
Introduction
Following unilateral damage of the primary visual cortex one of the most common visual field defects observed is Homonymous Hemianopia (HH), a loss of vision of the contralesional hemifield in each eye. The ipsilesional (“intact”) part of the central visual field is often used to compensate for difficulties encountered in the peripheral hemianopic visual field. However, the quality of vision within the central visual field is not well-known.Methods
To better describe and understand visual processing in hemianopia, two tasks were conducted with 25 healthy controls, six left hemianopes, and five right hemianopes. Filtered (in high, above 6 cycles/degree, or low, below 4 cycles/degree, spatial frequencies - HSF and LSF, respectively) and unfiltered natural scene images (5° of visual angle) were briefly presented (100 msec) centrally on a computer screen. Participants were required either to respond when a natural scene was presented (yes/no detection task) or to indicate if the stimulus was a city or a highway (categorization task).Results
The three groups showed similar accuracy levels but significant differences were observed in response times. More precisely, left hemianopes were impaired both in the detection and in the categorization tasks whereas right hemianopes were only impaired in the categorization task. However, the three groups had similar responses to spatial frequencies: HSF were processed more slowly than LSF.Conclusions
Overall these results suggest that central vision is not intact in hemianopia. Lesion side selectively affects reaction times (RTs) in the detection and the categorization tasks, but does not seem to determine a specific deficit in spatial frequency processing. 相似文献992.
目的 建立比较分子力场分析法(CoMFA)和比较分子相似性指数分析法(CoMSIA)模型,研究茚并异喹啉酮类化合物对前列腺癌细胞DU-145增殖抑制活性的三维定量构效关系。方法 选取63个文献报道的茚并异喹啉酮类化合物,采用CoMFA和CoMSIA方法进行研究。在CoMFA研究中,系统考察了分子取向与网格平移对q2值的影响,并基于得到的最优q2值结果,考察了网格点步长对统计结果的影响;在CoMSIA研究中,系统考察了各种分子场组合、网格点步长和衰减因子对模型统计结果的影响。结果 衰减因子为0.35,网格点步长为0.15 nm 时,仅用疏水场就可以得到最佳模型,所建立CoMFA和CoMSIA模型的交叉验证系数q2值分别为0.630和0.635,都具有较强的预测能力。结论 CoMFA和CoMSIA模型的三维等值线图直观地解释了该类化合物的构效关系,阐明了化合物结构中各位置取代基对前列腺癌细胞DU-145增殖抑制活性的影响,为进一步结构优化以提高抗前列腺癌活性提供了重要的理论依据。 相似文献
993.
994.
Oligodeoxynucleotides (ODN) containing unmethylated CpG dinucleotides (CpG ODN) mimic the immunostimulatory activity of microbial DNA via Toll-like receptor (TLR)9. Previous studies indicated that human NK cells express functional TLR3 and TLR9, since their cytokine release and cytolytic function could be incremented by poly(I:C) or ODN A/B, respectively. We have now evaluated the capability of a novel class of CpG ODN, termed ODN C, to modulate the function of human NK cells in the presence of exogenous cytokines. We show that NK cells isolated from peripheral blood and cultured with ODN C, in the presence of either IL-12 or IL-8, express higher levels of CD69 as compared to those stimulated with either ODN A or ODN B. Moreover, NK cells cultured with ODN C displayed higher cytolytic activity against tumor cell lines. These effects were not confined to freshly isolated peripheral blood NK cells since polyclonal NK cell populations that had been cultured in the presence of exogenous IL-2 for several weeks also displayed higher cytolytic activity and cytokine release after culture in the presence of ODN C. Remarkably, NK cells displaying poor responses to ODN A/B were efficiently stimulated by ODN C. 相似文献
995.
《Acta oto-laryngologica》2012,132(1):67-71
It has been reported that skin-test reactivity and rhinitis symptom severity weaken in the course of time. A corresponding weakening might also be seen in non-specific nasal hyper-reactivity, but the relationships of these responses are poorly understood. Our aim was to measure nasal responsiveness to histamine in a series of patients with long-continuing allergic rhinitis and to compare these measurements with skin test responses, allergen provocation and changes in severity of allergic rhinitis symptoms. A total of 73 patients in whom allergic rhinitis had been verified over 20 years earlier were re-interviewed and re-investigated. Skin prick tests with common allergens were performed and the presence of nasal allergy was confirmed by allergen provocation. Non-specific nasal hyper-reactivity was determined with nasal histamine challenge using four concentrations of histamine phosphate. The response was registered by counting sneezes, recording changes in nasal discharge and mucosal swelling and measuring nasal airway resistance. Sneezing and discharge scores showed that milder non-specific nasal hyper-reactivity was associated with lack of reactivity in skin prick tests and nasal allergen challenge. No association was observed between allergy test results and changes in nasal airway resistance during the histamine provocation. In most patients the symptoms of rhinitis had become milder or disappeared during the follow-up, but the results of the histamine challenge showed no relationship with the changes in symptom severity. In patients with allergic rhinitis, reactivity to histamine is associated with a concomitant change in skin and nasal mucosal reactivity to allergens. 相似文献
996.
Eva Lion Evelien L.J.M. Smits Zwi N. Berneman Viggo F.I. Van Tendeloo 《The oncologist》2012,17(10):1256-1270
The cytotoxic and regulatory antitumor functions of natural killer (NK) cells have become attractive targets for immunotherapy. Manipulation of specific NK cell functions and their reciprocal interactions with dendritic cells (DCs) might hold therapeutic promise. In this review, we focus on the engagement of NK cells in DC-based cancer vaccination strategies, providing a comprehensive overview of current in vivo experimental and clinical DC vaccination studies encompassing the monitoring of NK cells. From these studies, it is clear that NK cells play a key regulatory role in the generation of DC-induced antitumor immunity, favoring the concept that targeting both innate and adaptive immune mechanisms may synergistically promote clinical outcome. However, to date, DC vaccination trials are only infrequently accompanied by NK cell monitoring. Here, we discuss different strategies to improve DC vaccine preparations via exploitation of NK cells and provide a summary of relevant NK cell parameters for immune monitoring. We underscore that the design of DC-based cancer vaccines should include the evaluation of their NK cell stimulating potency both in the preclinical phase and in clinical trials. 相似文献
997.
Yoonhee Lee Youn-Duk Kim Hye-Jin Hyun Long-quan Pi Xinghai Jin Won-Soo Lee 《ANNALS OF DERMATOLOGY》2011,23(4):455-462
Background
Hair dryers are commonly used and can cause hair damage such as roughness, dryness and loss of hair color. It is important to understand the best way to dry hair without causing damage.Objective
The study assessed changes in the ultra-structure, morphology, moisture content, and color of hair after repeated shampooing and drying with a hair dryer at a range of temperatures.Methods
A standardized drying time was used to completely dry each hair tress, and each tress was treated a total of 30 times. Air flow was set on the hair dryer. The tresses were divided into the following five test groups: (a) no treatment, (b) drying without using a hair dryer (room temperature, 20℃), (c) drying with a hair dryer for 60 seconds at a distance of 15 cm (47℃), (d) drying with a hair dryer for 30 seconds at a distance of 10 cm (61℃), (e) drying with a hair dryer for 15 seconds at a distance of 5 cm (95℃). Scanning and transmission electron microscopy (TEM) and lipid TEM were performed. Water content was analyzed by a halogen moisture analyzer and hair color was measured with a spectrophotometer.Results
Hair surfaces tended to become more damaged as the temperature increased. No cortex damage was ever noted, suggesting that the surface of hair might play a role as a barrier to prevent cortex damage. Cell membrane complex was damaged only in the naturally dried group without hair dryer. Moisture content decreased in all treated groups compared to the untreated control group. However, the differences in moisture content among the groups were not statistically significant. Drying under the ambient and 95℃ conditions appeared to change hair color, especially into lightness, after just 10 treatments.Conclusion
Although using a hair dryer causes more surface damage than natural drying, using a hair dryer at a distance of 15 cm with continuous motion causes less damage than drying hair naturally. 相似文献998.
Rosacea is a chronic inflammatory skin condition characterized by cutaneous hypersensitivity. There are many therapeutic options available for the treatment of rosacea, but none are curative. Since the pathogenesis of rosacea remains elusive, it is not surprising that no single treatment is paramount and that many patients find therapies unsatisfactory or even exacerbating. Treatments are prescribed to work in concert with each other in order to ameliorate the common clinical manifestations, which include: papules and pustules, telangiectasias, erythema, gland hypertrophy, and ocular disease. The most validated topical therapies include metronidazole, azelaic acid, and sodium sulfacetamide-sulfur. Many other topical therapies, such as calcineurin inhibitors, benzoyl peroxide, clindamycin, retinoids, topical corticosteroids, and permethrin have demonstrated varying degrees of success. Due to the inconsistent results of the aforementioned therapies patients are increasingly turning to alternative products containing natural ingredients or botanicals to ease inflammation and remit disease. Additional research is needed to elucidate the benefits of these ingredients in the management of rosacea, but some important considerations regarding the natural ingredients with clinical data will be discussed here. 相似文献
999.
Sterer N Nuas S Mizrahi B Goldenberg C Weiss EI Domb A Davidi MP 《Journal of dentistry》2008,36(7):535-539
OBJECTIVE: The aim of the present study was to test the effect of a palatal mucoadhesive tablet containing an herbal formulation on oral malodor production and volatile sulfide compound (VSC) levels, and to evaluate its antimicrobial activity. METHODS: A total of 56 healthy young volunteers participated in experiments 1 and 2. The palatal adhesive tablets were prepared with different active ingredients (herbal formulation, zinc and chlorhexidine), or without an active ingredient as control (placebo). Measurement included odor judge scores (two judges) and VSC readings by a sulfide monitor (Halimeter). In experiment 3, the antimicrobial activity of the herbal formulation ingredients (i.e. sage, Echinacea, Lavender and Mastic gum) were tested against three oral pathogens (Streptoccocus mutans, Porphyromonas gingivalis and Candida albicans) by the agar diffusion test. RESULTS: Application of the palatal adhesive tablets containing herbal formulation resulted in a significant reduction in both oral malodor scores (p<0.001) and VSC levels (p=0.013). Herbal formulation showed higher significance in VSC reduction (p=0.001), as compared to zinc and chlorhexidine (p=0.024 and 0.032, respectively). Sage, Lavender and Mastic gum showed antimicrobial activity against all three oral pathogens. CONCLUSIONS: Results of the present study suggest that the palatal adhesive tablets containing herbal formulation may serve as an effective means of treatment for patients complaining of oral malodor. 相似文献
1000.
Windisch P Szendroi-Kiss D Horváth A Suba Z Gera I Sculean A 《Clinical oral investigations》2008,12(3):257-264
Treatment of intrabony periodontal defects with a combination of a natural bone mineral (NBM) and guided tissue regeneration (GTR) has been shown to promote periodontal regeneration in intrabony defects. In certain clinical situations, the teeth presenting intrabony defects are located at close vicinity of the resorbed alveolar ridge. In these particular cases, it is of clinical interest to simultaneously reconstruct both the intrabony periodontal defect and the resorbed alveolar ridge, thus allowing insertion of endosseous dental implants. The aim of the present study was to present the clinical and histological results obtained with a new surgical technique designed to simultaneously reconstruct the intrabony defect and the adjacently located resorbed alveolar ridge. Eight patients with chronic advanced periodontitis displaying intrabony defects located in the close vicinity of resorbed alveolar ridges were consecutively enrolled in the study. After local anesthesia, mucoperiosteal flaps were raised, the granulation tissue removed, and the roots meticulously scaled and planed. A subepithelial connective tissue graft was harvested from the palate and sutured to the oral flap. The intrabony defect and the adjacent alveolar ridge were filled with a NBM and subsequently covered with a bioresorbable collagen membrane (GTR). At 11-20 months (mean, 13.9+/-3.9 months) after surgery, implants were placed, core biopsies retrieved, and histologically evaluated. Mean pocket depth reduction measured 3.8+/-1.7 mm and mean clinical attachment level gain 4.3+/-2.2 mm, respectively. Reentry revealed in all cases a complete fill of the intrabony component and a mean additional vertical hard tissue gain of 1.8+/-1.8 mm. The histologic evaluation indicated that most NBM particles were surrounded by bone. Mean new bone and mean graft area measured 17.8+/-2.8% and 32.1+/-8.3%, respectively. Within their limits, the present findings indicate that the described surgical approach may be successfully used in certain clinical cases to simultaneously treat intrabony defects and to reconstruct the resorbed alveolar ridge. 相似文献