全文获取类型
收费全文 | 2190篇 |
免费 | 130篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 130篇 |
妇产科学 | 17篇 |
基础医学 | 238篇 |
口腔科学 | 80篇 |
临床医学 | 256篇 |
内科学 | 493篇 |
皮肤病学 | 38篇 |
神经病学 | 53篇 |
特种医学 | 490篇 |
外科学 | 141篇 |
综合类 | 35篇 |
预防医学 | 70篇 |
眼科学 | 13篇 |
药学 | 169篇 |
1篇 | |
肿瘤学 | 101篇 |
出版年
2022年 | 5篇 |
2021年 | 11篇 |
2020年 | 16篇 |
2019年 | 13篇 |
2018年 | 26篇 |
2017年 | 22篇 |
2016年 | 28篇 |
2015年 | 39篇 |
2014年 | 38篇 |
2013年 | 38篇 |
2012年 | 57篇 |
2011年 | 53篇 |
2010年 | 50篇 |
2009年 | 60篇 |
2008年 | 44篇 |
2007年 | 37篇 |
2006年 | 49篇 |
2005年 | 81篇 |
2004年 | 53篇 |
2003年 | 53篇 |
2002年 | 80篇 |
2001年 | 84篇 |
2000年 | 69篇 |
1999年 | 75篇 |
1998年 | 106篇 |
1997年 | 94篇 |
1996年 | 112篇 |
1995年 | 78篇 |
1994年 | 74篇 |
1993年 | 61篇 |
1992年 | 75篇 |
1991年 | 60篇 |
1990年 | 56篇 |
1989年 | 73篇 |
1988年 | 72篇 |
1987年 | 77篇 |
1986年 | 35篇 |
1985年 | 50篇 |
1984年 | 37篇 |
1983年 | 36篇 |
1982年 | 30篇 |
1981年 | 20篇 |
1980年 | 12篇 |
1979年 | 8篇 |
1978年 | 11篇 |
1977年 | 12篇 |
1976年 | 10篇 |
1975年 | 11篇 |
1974年 | 5篇 |
1954年 | 5篇 |
排序方式: 共有2334条查询结果,搜索用时 0 毫秒
991.
Quirynen M Zhao H Avontroodt P Soers C Pauwels M Coucke W van Steenberghe D 《Journal of periodontology》2003,74(7):937-944
BACKGROUND: Breath odor is scored by different techniques, each with its own shortcomings. Organoleptic ratings are uncomfortable for the patient, subjective, influenced by external parameters including food and cosmetics, and especially lack international calibration. Portable sulphide monitors are relatively expensive and neglect several major malodorous molecules (e.g., butyric and propionic acids, putrescine, and cadaverine). Gas chromatography necessitates expensive devices and experienced technicians. This pilot study explored the applicability of a new technique (saliva incubation) by comparing its discrimination power, in a morning bad breath inhibition study of antiseptics, to those of hydrogen sulphide (H2S) measurement devices and organoleptic ratings. METHODS: After a professional cleaning, 8 periodontally healthy students abstained from all means of mechanical plaque control for 5 experimental periods of 7 days, with intervening washout periods of at least 2 weeks. During each experimental period, the students rinsed only twice daily with different antiseptics. At day 7, morning breath was scored clinically (volatile sulphide compound [VSC] level and organoleptic ratings), and 1.5 ml of saliva was collected and divided between 3 glass tubes that were sealed and incubated (37 degrees C, anaerobic chamber). Immediately after collection and after 3 and 6 hours of incubation, the headspace air in one of the tubes was examined for VSC production and organoleptic measurements. RESULTS: The investigations of the incubated saliva correlated well with the 7-day intraoral VSC recordings and organoleptic ratings (P < or = 0.005). Moreover, evaluations showed a similar interproduct ranking for their efficacy in malodor control. The power analyses indicated a higher discrimination power for the saliva incubation test than for the intraoral registrations. CONCLUSIONS: The strong correlation between odor production of incubated saliva and clinical assessments suggests that the saliva incubation test may be used as an indirect method to measure oral malodor and can be employed to investigate the antimalodor effectiveness of oral hygiene products. 相似文献
992.
Dierickx K Pauwels M Laine ML Van Eldere J Cassiman JJ van Winkelhoff AJ van Steenberghe D Quirynen M 《Journal of periodontology》2003,74(6):844-848
BACKGROUND: Porphyromonas gingivalis, a key pathogen in periodontitis, is able to adhere to and invade the pocket epithelium. Different capsular antigens of P. gingivalis have been identified (K-serotyping). These P. gingivalis capsular types show differences in adhesion capacity to human cell lines or to cells cultured on a feeder layer or stromal equivalent. METHODS: The adhesion capacity of different P. gingivalis serotypes (6 capsular types and non-encapsulated strains) was compared on in vitro cultured epithelial monolayers from periodontal pockets of patients with periodontitis. The degree of adherence of P. gingivalis was evaluated by both culture and fluorescence microscopy. RESULTS: Non-encapsulated strains adhered significantly more than their capsulated variants. Capsule type 4 (K-4) adhered slightly better than the remaining K-types. CONCLUSION: This study indicates that the presence and type of capsule have a significant influence on the initial adhesion of P. gingivalis to human periodontal pocket epithelial cells. 相似文献
993.
The purpose of this review is to explore the concept of immediate loading as it pertains to dental implants and the indications for clinical practice. The definition of immediate loading will be considered together with a review of the relevant literature in an attempt to provide evidence-based guidelines for successful implementation into practice.
A search of electronic databases including Medline, PubMed and the Cochrane Database of Systematic Reviews was undertaken using the terms ``immediate loading', ``dental implants', ``immediate function', ``early loading', ``oral implants', ``immediate restoration' and ``systematic review'. This was supplemented by handsearching in peer-reviewed journals and cross-referenced with the articles accessed. Emphasis was given to systematic reviews and controlled clinical trials.
A definition of immediate loading was suggested pertinent to the realities of logistics in clinical practice with respect to application and time frame. The literature was evaluated and shown to be limited with significant shortcomings. Guidelines and recommendations for clinical protocols were suggested and illustrated by examples of case types with a minimum of 1–3 years follow-up. A list of additional references for further reading was provided.
Within the limitations of this review, there is evidence to suggest that immediate loading protocols have demonstrated high implant survival rates and may be cautiously recommended for certain clinical situations. However, more high level evidence studies, preferably randomized controlled trials (RCTs), over a long time frame are required to show a clear benefit over more conventional loading protocols. 相似文献
A search of electronic databases including Medline, PubMed and the Cochrane Database of Systematic Reviews was undertaken using the terms ``immediate loading', ``dental implants', ``immediate function', ``early loading', ``oral implants', ``immediate restoration' and ``systematic review'. This was supplemented by handsearching in peer-reviewed journals and cross-referenced with the articles accessed. Emphasis was given to systematic reviews and controlled clinical trials.
A definition of immediate loading was suggested pertinent to the realities of logistics in clinical practice with respect to application and time frame. The literature was evaluated and shown to be limited with significant shortcomings. Guidelines and recommendations for clinical protocols were suggested and illustrated by examples of case types with a minimum of 1–3 years follow-up. A list of additional references for further reading was provided.
Within the limitations of this review, there is evidence to suggest that immediate loading protocols have demonstrated high implant survival rates and may be cautiously recommended for certain clinical situations. However, more high level evidence studies, preferably randomized controlled trials (RCTs), over a long time frame are required to show a clear benefit over more conventional loading protocols. 相似文献
994.
Quirynen M Mongardini C de Soete M Pauwels M Coucke W van Eldere J van Steenberghe D 《Journal of clinical periodontology》2000,27(8):578-589
BACKGROUND/AIMS: Recent studies reported significant additional clinical and microbiological improvements when severe adult periodontitis was treated by means of a "one-stage full-mouth" disinfection instead of a standard treatment strategy with consecutive root planings quadrant per quadrant. The one stage full-mouth disinfection procedure involves scaling and root planing of all pockets within 24 h in combination with an extensive application of chlorhexidine to all intra-oral niches such as periodontal pockets, tongue dorsum, tonsils (chairside, and at home for 2 months). This study aims to examine the relative importance of the use of chlorhexidine in the one stage full-mouth disinfection protocol. METHODS: Therefore, 3 groups of 12 patients each with advanced periodontitis were followed, both from a clinical and microbiological point of view, over a period of 8 months. The patients from the control group were scaled and root planed, quadrant per quadrant. at two-week intervals. The 2 other groups underwent a one stage full-mouth scaling and root planing (all pockets within 24 h) with (Fdis) or without (FRp=full-mouth root planing) the adjunctive use of chlorhexidine. At baseline and after 1, 2, 4 and 8 months, the following clinical parameters were recorded: plaque and gingivitis indices, probing depth, bleeding on probing and clinical attachment level. Microbiological samples were taken from different intra-oral niches (tongue, mucosa, saliva and pooled samples from single- and multi-rooted teeth). The samples were cultured on selective and non-selective media in order to evaluate the number of CFU/ml for the key-periodontopathogens. At baseline, an anonymous questionnaire was given to the patients to record the perception of each treatment (post operative pain, fever, swelling etc.). RESULTS: All 3 treatment strategies resulted in significant improvements for all clinical parameters, but the Fdis and FRp patients reacted always significantly more favourably than the control group, with an additional probing depth reduction of +/- 1.5 mm and an additional gain in attachment of +/- 2 mm (for pockets > or = 7 mm). Also from a microbiological point of view both the FRp and Fdis patients showed additional improvements when compared to the control group, as well in the reduction of spirochetes and motile organisms as in the number of CFU/ml of the key-pathogens, especially when the subgingival plaque samples were considered. The differences between FRp and Fdis patients were negligible. CONCLUSIONS: These findings suggest that the benefits of a "one-stage full-mouth disinfection" in the treatment of patients suffering from severe adult periodontitis probably results from the full-mouth scaling and root planing within 24 h rather than the beneficial effect of chlorhexidine. The raise in body temperature the second day after the full-mouth scaling and root planing seems to indicate a Shwartzman reaction. 相似文献
995.
Alex N Bastick Janet Wesseling Jurgen Damen Saskia PJ Verkleij Pieter J Emans Patrick JE Bindels Sita MA Bierma-Zeinstra 《The British journal of general practice》2016,66(642):e32-e39
Background
GPs have high consultation rates for symptoms related to knee osteoarthritis (OA). Many risk factors for symptomatic knee OA progression remain unknown.Aim
To define distinct knee pain trajectories in individuals with early symptomatic knee OA and determine the risk factors for these pain trajectories.Design and setting
Data were obtained from the multicentre prospective Cohort Hip and Cohort Knee study in the Netherlands. Participants with knee OA, according to the clinical criteria of the American College of Rheumatology, and a completed 5-year follow-up were included.Method
Baseline demographic, anamnestic, and physical examination characteristics were assessed. Outcome was annually assessed by the Numeric Rating Scale for pain. Pain trajectories were retrieved by latent class growth analysis. Multinomial logistic regression was used to calculate relative risk ratios.Results
In total, 705 participants were included. Six distinct pain trajectories were identified with favourable and unfavourable courses. Statistically significant differences were found in baseline characteristics, including body mass index (BMI), symptom severity, and pain coping strategies between the different trajectories. Higher BMI, lower level of education, greater comorbidity, higher activity limitation scores, and joint space tenderness were more often associated with trajectories characterised by more pain at first presentation and pain progression — compared with the reference group with a mild pain trajectory. No association was found for baseline radiographic features.Conclusion
These results can help differentiate those patients who require more specific monitoring in the management of early symptomatic knee OA from those for whom a ‘wait-and-see’ policy seems justifiable. Radiography provided no additional benefit over clinical diagnosis of early symptomatic knee OA in general practice. 相似文献996.
Gerardus PJ van Hout Fatih Arslan Gerard Pasterkamp Imo E Hoefer 《Expert opinion on therapeutic targets》2016,20(2):223-239
Introduction: Myocardial infarction (MI) provokes an intense inflammatory response that can lead to left ventricular adverse remodeling and heart failure (HF). The prognosis of HF patients is poor and related to a decreased quality of life and considerable health care costs. Hence, targeting the early inflammatory response after MI provides an interesting target to attenuate left ventricular remodeling and prevent HF.Areas covered: In the current review, we discuss the theory that our immune system does not distinguish between self and non-self, but rather senses danger. So-called danger-associated molecular patterns (DAMPs) serve as ligands for pattern recognition receptors (PRRs), which act as signal transduction molecules to induce a pro-inflammatory state. Many different DAMPs and PRRs have been identified recently. Here, we provide a concise overview of their interactions as well as their role in the inflammatory response after MI.Expert opinion: Interference with Toll-like receptor (TLR) 2, TLR4 and NLRP3-inflammasome signaling has consistently shown to reduce infarct size and preserve cardiac function post-MI in experimental animal models. Since clinically applicable inhibitors have been developed for these pathways, the path has been cleared to assess whether these promising results can be translated into the human situation. 相似文献
997.
Amika S Singh Marijke JM Chin A Paw Stef PJ Kremers Tommy LS Visscher Johannes Brug Willem van Mechelen 《BMC public health》2006,6(1):1-15
Background
Immigrants to the U.S. are required to undergo overseas screening for tuberculosis (TB), but the value of evaluation and treatment following entry to the U.S. is not well understood. We determined the cost-effectiveness of domestic follow-up of immigrants identified as tuberculosis suspects through overseas screening.Methods
Using a stochastic simulation for tuberculosis reactivation, transmission, and follow-up for a hypothetical cohort of 1000 individuals, we calculated the incremental cost-effectiveness of follow-up and evaluation interventions. We utilized published literature, California Reports of Verified Cases of Tuberculosis (RVCTs), demographic estimates from the California Department of Finance, Medicare reimbursement, and Medi-Cal reimbursement rates. Our target population was legal immigrants to the United States, our time horizon is twenty years, and our perspective was that of all domestic health-care payers. We examined the intervention to offer latent tuberculosis therapy to infected individuals, to increase the yield of domestic evaluation, and to increase the starting and completion rates of LTBI therapy with INH (isoniazid). Our outcome measures were the number of cases averted, the number of deaths averted, the incremental dollar cost (year 2004), and the number of quality-adjusted life-years saved.Results
Domestic follow-up of B-notification patients, including LTBI treatment for latently infected individuals, is highly cost-effective, and at times, cost-saving. B-notification follow-up in California would reduce the number of new tuberculosis cases by about 6–26 per year (out of a total of approximately 3000). Sensitivity analysis revealed that domestic follow-up remains cost-effective when the hepatitis rates due to INH therapy are over fifteen times our best estimates, when at least 0.4 percent of patients have active disease and when hospitalization of cases detected through domestic follow-up is no less likely than hospitalization of passively detected cases.Conclusion
While the current immigration screening program is unlikely to result in a large change in case rates, domestic follow-up of B-notification patients, including LTBI treatment, is highly cost-effective. If as many as three percent of screened individuals have active TB, and early detection reduces the rate of hospitalization, net savings may be expected. 相似文献998.
999.
Tetraphenylphosphonium (TPP+) accumulation in rat brain synaptosomes was measured in the presence of various stimuli. TPP+ accumulation was sensitive to an increase of extracellular K+ or to the presence of Na+ channel neurotoxins. Examination of the effects of drugs with different physico-chemical properties on TPP+ accumulation showed that there was no effect under low and high K+ conditions; pimozide, flunarizine and buterizine were active in the presence of veratridine or scorpion venom. These results were compared to data obtained for the specific binding of [3H]BTX-B, a selective marker for the Na+ channel. It can be concluded that certain drugs, although active on [3H]BTX-B binding, are not necessarily identified when TPP+ is used as probe. 相似文献
1000.
J. W. Arndt G. E. Crama-Bohbouth H. W. Verspaget D. Blok A. S. Pena R. T. O. T. A. Tham I. T. Weterman C. B. H. W. Lamers E. K. J. Pauwels 《European journal of nuclear medicine and molecular imaging》1989,15(4):197-200
This study was undertaken to investigate the influence of various parameters of injected autologous 111In labelled granulocytes on scintigraphic image quality. Forty-two scintigrams of 37 patients with inflammatory bowel disease were evaluated. The images were divided into three groups according to quality: good, intermediate and poor. The relationships between image quality and such radiopharmaceutical parameters as injected dose of 111In, number of injected cells and specific activity were investigated. It appeared that in order to obtain interpretable images, a specific activity of at least 85 kBq 111In/million cells was necessary. The activity of the injected dose must exceed 7 MBq if poor quality images and very long acquisition times are to be avoided.Department of Gastroenterology 相似文献