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101.
OBJECTIVE: To estimate the prevalence of dental stains (DS) in competitive swimmers and quantify the risk of these stains compared with sportsmen in a non-swimmers group in Castellón, Spain. METHODS: Cross-sectional and case-control designs. Between July 1996 and March 1997, 404 subjects, (171 enrolled in two clubs of competitive swimming and 233 sportsmen from two schools), were examined in order to detect and classify yellowish-brown or dark-brown stains on the facial surface of the eight incisors. Participation rates were 88.6% for swimmers, and 95.7% for sportsmen. Mean of participants' age was 12 years, range 7-22 years. Castellón has three public competition swimming pools, two of which are indoors. Two of the pools used chloride products, and the third bromine for the disinfection of water. The recommended hygiene regulations were adhered to. RESULTS: Prevalence of DS was 60.2% in swimmers and 12.9% in sportsmen (P= 0.0001). Risk factors for DS included: use of competition swimming pools, age, gender, years of competition, daily consumption of coffee, red wine, and iron supplement during the last year. Professional dental cleanliness was a protective factor. In a logistic regression analysis, the use of competition swimming pools maintained a high risk of DS, odds ratio (OR)=9.28; 95% confidence interval (CI) 5.21-16.5, adjusted by the other variables. Amongst swimmers, more than 6 h of training a week increased the risk of these stains (OR=3.51; 95% CI 1.35-9.10). CONCLUSION: The study indicated a high risk of DS in competitive swimmers.  相似文献   
102.
OBJECTIVE: To investigate GDP opinions of the current referral system and to investigate the need and demand for telemedicine in oral surgery referrals. DESIGN: Postal questionnaire. SETTING: 400 GDPs in Greater Manchester. RESULTS: 84% participation rate. 48% were not satisfied overall with the service of their current specialist oral surgery referral site. The principal reason was the length of the waiting time for consultation and treatment. Distance for patients to travel to the specialist unit was also of concern, even though most patients (89%) travelled short distances (return journey of twelve miles or less). 23% of respondents wished to improve their ability to communicate with the oral surgeon and 70% wanted involvement in the patient consultation. Both of these requirements were more likely in younger practitioners. CONCLUSION: There is a need and demand for change in the referral system for oral surgery specialist care. Telemedicine could conceivably be one way to improve access to specialist oral surgery care.  相似文献   
103.
OBJECTIVE: To study the therapeutic prescribing of antibiotics by general dental practitioners. DESIGN: A postal questionnaire of National Health Service general dental practitioners in ten English Health Authorities. SUBJECTS: General dental practitioners (1,544) contracted to provide NHS treatment in the Health Authorities of Liverpool, Wirral, Oxfordshire, Buckinghamshire, Nottingham, North Nottinghamshire, Sheffield, Newcastle, Northumberland and North Tyneside. MAIN OUTCOME MEASURES: The questionnaires were analysed and the responses to each question expressed as absolute frequencies. RESULTS: Responses to the questionnaire were received from 929 (60.1%) practitioners. More than 95% of practitioners recognised the need for prescribing antibiotics where there was evidence of spreading infection. Some practitioners (12.5%) prescribed antibiotics for acute pulpitis and (3.3%) for chronic marginal gingivitis. Antibiotics were prescribed by practitioners before drainage of acute abscesses (69%) and by 23% after drainage. Practitioners were generally not influenced by patient's expectations of receiving antibiotics (92%), but would prescribe when under pressure of time (30.3%), if they were unable to make a definitive diagnosis (47.3%), or if treatment had to be delayed (72.5%). Amoxicillin was the most frequently prescribed antibiotic used for most clinical conditions apart from pericoronitis, acute ulcerative gingivitis and dry sockets where metronidazole was the drug of choice. There was a wide variety of dosage, frequency and duration for all the antibiotics used in the treatment of acute dental infections. CONCLUSIONS: The results obtained from this questionnaire support the conclusion that the therapeutic prescribing of antibiotics in general dental practice varies widely and is suboptimal. There is a clear need for the development of prescribing guidelines and educational initiatives to encourage the rational and appropriate use of the antibiotics in National Health Service general dental practice.  相似文献   
104.
A 14-year-old girl was referred to our clinic with a problem of a painless slow growing lesion for approximately three years. MR imaging findings of lesion was "retention cyst of the salivary gland". Controversially, the histological examination of the total excised specimen was "neurinoma" and that was inconsistent with MR findings. Neural tissue tumors of the oral cavity are rare, however, this diagnosis was confirmed by surgical excision and histopathological examination. There was a rare location of the lesion as well.  相似文献   
105.
Terminology of facial morphology in the vertical dimension   总被引:1,自引:0,他引:1  
Consideration of facial type plays an important role in the formulation of an orthodontic treatment plan and prognosis of treatment. Of particular importance is the vertical relationship, that is, whether an individual is long-faced (dolichofacial), or short-faced (brachyfacial). The vertical facial type provides a clue regarding the growth direction of the facial complex, and should be used with an anteroposterior classification to describe a patient's face. The potential for confusion in communicating vertical facial types exists due to the nature of the terminology in use. For example, the term dolichoprosopic as used in the Bimler analysis has an opposite meaning to the term dolichofacial. It would seem prudent that if such terminology is to be employed there should be some attempt at standardization, and at least an appreciation of the derivations of the terms, and their differences.  相似文献   
106.
The distribution of the cell adhesion proteins vitronectin, fibronectin, tenascin, and laminin as well as several integrin subunits, alpha 2, alpha 5, and alpha v, was studied in primate periodontal tissues. Full baboon mandibular sections were analyzed by immunohistochemical methods in order to localize the molecules studied in both soft and hard tissues. Vitronectin was associated with the connective tissue of the marginal gingiva, the periodontal ligament, as well as the endosteum and periosteum. A notable finding was the particularly high staining intensity of vitronectin in the periodontal ligament. Fibronectin was widely distributed in the periodontal connective tissue and was also localized to the pericellular matrix of osteocytes and blood vascular elements. Epithelial basement membranes stained positively for both fibronectin and tenascin. These proteins were also expressed in the periosteal and endosteal connective tissues and the periodontal ligament. The staining intensity for tenascin was higher in zones along the cementum and bone surfaces. Laminin was, characteristically, limited to basement membranes of epithelium and endothelium. The distribution of fibronectin, tenascin, and laminin is related to previous findings in other species. The localization of the several integrin alpha-subunits is also described in full baboon mandibular sections. The vitronectin receptor (alpha v) had a uniquely strong expression in osteoclasts of the alveolar bone and was found, at lesser intensity, on periodontal ligament fibroblasts. The fibronectin receptor alpha subunit, alpha 5, was also observed on osteoclasts, and, in addition, was widely distributed on fibroblasts, cementoblasts, and osteoblasts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
107.
An account is given of a patient who had multiple canalicular adenomas in the upper lip and adjacent oral mucosa. A few months after these had been excised, several more tumors of the same type developed. Microscopic examination also revealed numerous tiny foci of adenomatous proliferation within otherwise normal salivary gland lobules. We suggest that this phenomenon represents a field neoplastic change although it appears to be benign.  相似文献   
108.
The purpose of this study was to determine whether erroneous kVp meter readings, induced by plastic wrap, affected the actual kVp (output) of a dental X-ray machine. To evaluate the effect of plastic wrap on dental X-ray machine kVp meters, a radiation output device was used to measure output in mR/ma.s. An intraoral dental X-ray unit (S.S. White Model #90W) was used to make the exposures. First, the kVp meter was not covered with plastic wrap and output readings were recorded at various kVp settings with the milliamperage and time held constant. Secondly, the same kVp settings were selected before the plastic wrap was placed. Milliamperage and time were again held to the same constant. The X-ray console was then covered with plastic wrap prior to measuring the output for each kVp. The wrap possessed a static charge. This charge induced erroneous kVp meter readings. Out-put readings at the various induced kVp settings were then recorded. A kVp of 50 with no wrap present resulted in the same output as a kVp of 50 induced to read 40 or 60 kVp by the presence of wrap. Similar results were obtained at other kVp settings. This indicates that the plastic wrap influences only the kVp meter needle and not the actual kilovoltage of the X-ray machine. Dental X-ray machine operators should select kVp meter readings prior to placing plastic wrap and should not adjust initial settings if the meter is deflected later by the presence of wrap. The use of such a procedure will result in proper exposures, fewer retakes, and less patient radiation. If plastic wrap leads to consistent exposure errors, clinicians may wish to use a 0.5% sodium hypochlorite disinfectant as an alternative to the barrier technique.  相似文献   
109.
Pulp stump and periapical tissue reaction to root canal filling with material containing calcium hydroxide and potassium nitrate after subtotal vital extirpation of the pulp was studied in 12 teeth of 6 green monkeys. Use of the material containing potassium nitrate was found to result on the 90th day of the experiment in the formation of a biologic barrier of secondary cement at the dental root apex. Such result was not achieved with calcium hydroxide-containing material. Other advantages of potassium nitrate-containing material were detected, consisting in a more rapid recovery of structural shifts in the pulp stump and periapical tissues.  相似文献   
110.
Longevity of posterior restorations   总被引:3,自引:0,他引:3  
The efficacy of restorative dentistry is dependent on a number of factors, including material quality, operator proficiency and the oral hygiene of the patient. The sum effect of all factors can be measured by recording the longevity of the restorations. Many studies focus on the age of restorations at the time of failure, others include the longevity of restorations which remain in situ. The surveys may be either longitudinal, prospective or retrospective, or cross-sectional retrospective studies of dental records. They are all hampered by the lack of uniform criteria defining when to place and replace restorations and by variations in decision-making between clinicians. The present review paper shows that the longevity of amalgam restorations has been studied most frequently. About 50 per cent of all amalgam restorations exceed 8-10 years in age, cast gold restorations may last longer and multisurfaced composite restorations have a shorter life-span. Glass ionomer cements lack the physical properties needed for large posterior restorations. The results of detailed longevity studies should be the basis for selection of materials and techniques in operative/conservative treatment. The cost of dental treatment should be related to the expected lifetime of the tooth rather than to the immediate cost of a simple restoration.  相似文献   
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