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51.
The Second Scientific Fibre Reinforcement Symposium was held in Nijmegen, The Netherlands, on October 13th, 2001. The participants were invited speakers with extensive scientific and clinical backgrounds in glass fiber and polyethylene fiber research. The symposium reports focused on four areas of fiber reinforcement research: materials development, laboratory testing, clinical systems development, and clinical data. The consensus reached on the current status and future directions of this technology is reported here.  相似文献   
52.
53.
Amyloidosis with oral involvement. Case report   总被引:2,自引:0,他引:2  
A patient with chronic renal failure was investigated after complaining of oral discomfort which was found to be due to macroglossia and generalized involvement of the oral soft tissues by amyloidosis. A search for multiple myeloma proved to be positive. She also had a previous history of Carpal-tunnel syndrome. Despite an initial good response to treatment with phenylalanine nitrogen mustard (melphalan hydrochloride), she finally succumbed to end-stage renal failure.  相似文献   
54.
BACKGROUND: Health care providers have focused on outcome measures to determine the success or failure of treatment. In periodontics, there is no consistent view regarding what outcome measure(s) is(are) important for successful treatment. This study used a Delphi surveying technique to determine which outcome measures were clinically relevant to an expert panel of periodontists. METHODS: The Delphi surveyed 35 periodontists from the United States to determine the level of importance of attachment level, probing depth, furcation involvement, mobility, plaque, inflammation, esthetics, pain, and patient satisfaction following periodontal treatment of posterior teeth in a patient with severe chronic periodontitis. The Delphi panelists were questioned concerning the relative importance of each outcome measure, a minimally acceptable level considered necessary for success for each outcome measure, and the length of time required for these outcome measures to remain stable. RESULTS: Following two rounds of Delphi surveys, the panelists considered the control of pain to be an "extremely important" outcome measure for successful periodontal treatment. Attachment levels, probing depths, plaque levels, degree of inflammation, function, furcation involvement, and patient satisfaction were considered to be "very important" outcomes for successful periodontal treatment. The minimally acceptable reduction in probing depths following 1 year of treatment was 2 mm; whereas up to 1 mm of attachment loss was considered acceptable. The panel found that Glickman grade 2 furcation involvement or Miller degree II mobility would be considered an acceptable outcome for clinical success. Finally, the panel agreed that the 1-year results of treatment should remain stable for a minimum of 5 years. CONCLUSIONS: The Delphi surveying technique proved useful in developing a hierarchy for the relevance of periodontal outcome measures. Absence of pain was the only outcome measure considered to be "extremely important" for successful therapy. Although panelists considered attachment loss, furcation invasions, and mobility as "very important" outcomes, they were willing to accept loss of attachment of up to 1 mm, grade 2 furcation involvement, and degree II mobility following treatment as long as outcomes remained stable for 5 years. These data suggest that minimal standards for success of posterior teeth can be established among periodontal practitioners.  相似文献   
55.
BACKGROUND: Valuable decision making for periodontal treatment success in situations where there is ambiguous or conflicting information was previously reported using a consensus building method, the Delphi survey, for posterior teeth with chronic periodontitis. This study focuses on outcome measures relevant in assessing therapy of anterior teeth with chronic periodontitis. METHODS: The Delphi panelists were the same American periodontists who participated in the previous Delphi survey evaluating successful therapy in posterior teeth. In this study, panelists determined the level of importance of attachment level, probing depth, mobility, plaque, inflammation, esthetics, pain, and patient satisfaction following periodontal treatment of a single tooth or multiple anterior teeth in a patient with severe chronic periodontitis. The panelists were questioned concerning the relative importance of each outcome measure, a minimally acceptable level considered necessary for success for each outcome measure, and the length of time required for these outcome measures to remain stable. RESULTS: The 35 panelists considered the control of pain, esthetics, and patient satisfaction to be "extremely important" outcome measures for successful periodontal treatment of single or multiple teeth. Attachment levels, probing depths, plaque levels, degree of inflammation, and mobility (for multiple teeth) were considered to be "very important" outcomes. The minimally acceptable reduction in probing depths following 1 year of treatment was 2 mm; whereas 2 mm of attachment gain was considered necessary for successful treatment. The panel also found a Miller degree I mobility as an acceptable outcome for clinical success. Finally, the panel agreed that the 1-year results of treatment should remain stable for a minimum of 5 years. CONCLUSIONS: The Delphi technique proved a practical instrument to transform expert opinion into a group consensus for relevant periodontal outcome measures. Absence of pain, esthetics, and patient satisfaction were outcome measures considered "extremely important" for successful therapy. Although panelists considered attachment loss, probing depths, and mobility somewhat less important outcomes, they wanted an attachment gain of 2 mm and would accept a degree I mobility as long as outcomes remained stable for 5 years. These data suggest that minimal standards for successful therapy of anterior teeth can be established among periodontal practitioners.  相似文献   
56.
Mercury has been used in both medicine and dentistry for centuries. Recent media attention regarding the increased levels of mercury in dietary fish, high levels of mercury in air emissions, and conjecture that certain diseases may be caused by mercury exposure has increased public awareness of the potential adverse health effects of high doses of mercury. Dentistry has been criticized for its continued use of mercury in dental amalgam for both public health and environmental reasons. To address these concerns, dental professionals should understand the impact of the various levels and types of mercury on the environment and human health. Mercury is unique in its ability to form amalgams with other metals. Dental amalgam--consisting of silver, copper, tin, and mercury--has been used as a safe, stable, and cost-effective restorative material for more than 150 years. As a result of this use, the dental profession has been confronted by the public on two separate health issues concerning the mercury content in amalgam. The first issue is whether the mercury amalgamated with the various metals to create dental restorations poses a health issue for patients. The second is whether the scraps associated with amalgam placement and the removal of amalgam restorations poses environmental hazards which may eventually have an impact on human health. Despite the lack of scientific evidence for such hazards, there is growing pressure for the dental profession to address these health issues. In this article, the toxicology of mercury will be reviewed and the impact of amalgam on health and the environment will be examined.  相似文献   
57.
Academic dental institutions are the fundamental underpinning of the nation's oral health. Education, research, and patient care are the cornerstones of academic dentistry that form the foundation upon which the dental profession rises to provide care to the public. The oral health status of Americans has improved dramatically over the past twenty-five to thirty years. In his 2000 report on oral health, the Surgeon General acknowledges the success of the dental profession in improving the oral health status of Americans over the past twenty-five years, but he also juxtaposes this success to profound and consequential disparities in the oral health of Americans. In 2002, the American Dental Education Association brought together an ADEA President's Commission of national experts to explore the roles and responsibilities of academic dental institutions in improving the oral health status of all Americans. They have issued this report and made a variety of policy recommendations, including a Statement of Position, to the 2003 ADEA House of Delegates. The commission's work will help guide ADEA in such areas as: identifying barriers to oral health care, providing guiding principles for academic dental institutions, anticipating workforce needs, and improving access through a diverse workforce and the types of oral health providers, including full utilization of allied dental professionals and collaborations with colleagues from medicine.  相似文献   
58.
This experiment investigated the ability of tooth-colored mineral trioxide aggregate (MTA) to maintain an apical seal in the presence of bacteria when contaminated with blood, saline or saliva. Ninety extracted human teeth with single canals were randomly placed into six groups of 15. Canals were prepared to size 50. The apical 3 mm of each root was removed and 3 mm root-end preparations were made with a #329 bur. Root-end preparations in groups 1 through 3 were filled with MTA after contamination with blood, saline, or saliva, respectively. In group 4, uncontaminated root-end preparations were filled with MTA. Groups 5 and 6 served as negative and positive controls. A tube/tooth assembly was utilized to suspend each root end in Trypticase Soy Broth (TSB). The access chambers were filled with Staphylococcus epidermidis. Positive growth over thirty days was demonstrated by turbidity of the TSB. Vitek analysis was used to confirm the presence of S. epidermidis in the positive samples. Data evaluation consisted of a chi(2) analysis (p < 0.05). Although all experimental groups demonstrated leakage, tooth-colored MTA contaminated with saliva (group 3) leaked significantly more than the uncontaminated tooth-colored MTA (group 4) (p = 0.028).  相似文献   
59.
PURPOSE: The purpose of this study was to compare the linear dimensional accuracy and the handling characteristics of 7 die materials. MATERIALS AND METHODS: A master die analogous to a complete veneer crown preparation was machined from medical grade stainless steel, and 3 measurements (1: vertical; 2 and 3: horizontal) were made from 3 scribed reference lines. Individual polyvinylsiloxane impressions were made (n = 10) for each of the specimens. The fabricated dies were measured (50x) to the nearest 0.0001 mm. Data were subject to ANOVA/Duncan tests at significance level 0.05 and pairwise comparisons. RESULTS: Type IV resin-impregnated dental stone and copper-plated dies most closely approximated the dimensions of the master die, and were not significantly different from each other in any of the pairwise comparisons. Conventional Types IV and V dental stone dies exhibited setting expansion within the range appropriate for gypsum. Epoxy resin die materials demonstrated shrinkage comparable to the expansion of the Types IV and V dies. Polyurethane dies displayed a combination of linear expansion and shrinkage. Bis-acryl composite resin dies had excessive shrinkage. CONCLUSIONS: Type IV resin-impregnated dental stone and copper-plated dies were more dimensionally accurate than the other die materials tested.  相似文献   
60.
Adult male rats were maintained on a wholly liquid diet for 9 days. The three pairs of major glands were removed, weighed, histologically sectioned and examined by stereological and morphometric techniques. The results were compared with the same glands from control rats maintained on normal hard diet and water, and the extent of the differences was compared between the three different types of gland. Up to 50% of the serous acinar volume in the parotid glands, but only 15% in the submandibular glands, was lost after liquid feeding. There was no loss of the mucous acinar tissue in the sublingual gland. Mean acinar diameters were reduced by 33% in parotids and 15% in submandibular glands after liquid feeding, whereas the mucous acini of the sublingual gland remained unaltered. The results point to varying levels of susceptibility to the loss of masticatory reflexes between the parotid serous acini and the submandibular serous acini, and show that the morphology of the sublingual mucous acini is independent of masticatory reflex stimulation. The reductions in acinar diameters suggest that most of the glandular atrophy after liquid feeding is due to acinar cell shrinkage rather than to losses of acinar cell numbers in both parotid and submandibular glands.  相似文献   
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