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951.
INTRODUCTION: Actinobacillus actinomycetemcomitans has been implicated in the etiology of aggressive periodontitis. In this study, we applied a novel nucleic acid amplification method, called loop-mediated isothermal amplification (LAMP), which amplifies DNA with high specificity, efficiency and rapidity under isothermal conditions, allowing the rapid detection of A. actinomycetemcomitans. METHODS: We designed the primers for detecting A. actinomycetemcomitans and evaluated the specificity and sensitivity of the assay. RESULTS: The LAMP primers used in this study successfully amplified serotypes a-e of A. actinomycetemcomitans, while other oral bacteria were not amplified. By measuring the precipitation of magnesium pyrophosphate, we could quantify the chromosomal DNA of A. actinomycetemcomitans. The detection limits using the real-time turbidimetry analysis were 5.8 x 10(2)-5.8 x 10(7) copies of A. actinomycetemcomitans template DNA per reaction tube. In addition, the LAMP assay was used for the rapid detection of A. actinomycetemcomitans in clinical specimens from eight individuals. The results with the LAMP method were similar to those using conventional polymerase chain reaction. CONCLUSION: Our results suggest that the LAMP-based assay is very useful for the rapid detection of A. actinomycetemcomitans.  相似文献   
952.
Longitudinal study of bone density and periodontal disease in men   总被引:2,自引:0,他引:2  
Bone loss is a feature of both periodontitis and osteoporosis, and periodontal destruction may be influenced by systemic bone loss. This study evaluated the association between periodontal disease and bone mineral density (BMD) in a cohort of 1347 (137 edentulous) older men followed for an average of 2.7 years. Participants were recruited from the Osteoporotic Fractures in Men Study. Random half-mouth dental measures included clinical attachment loss (CAL), pocket depth (PD), calculus, plaque, and bleeding. BMD was measured at the hip, spine, and whole-body, by dual-energy x-ray absorptiometry, and at the heel by ultrasound. After adjustment for age, smoking, race, education, body mass index, and calculus, there was no association between number of teeth, periodontitis, periodontal disease progression, and either BMD or annualized rate of BMD change. We found little evidence of an association between periodontitis and skeletal BMD among older men.  相似文献   
953.
Yin W  Feng Y  Hu D  Ellwood RP  Pretty IA 《Caries research》2007,41(3):186-189
The aim of this study was to determine the impact of analysis patch border inclusion or exclusion on the reliability of quantitative laser fluorescence (QLF) analyses of lesions close to the gingival margin. Ninety-three lesions on the maxillary anterior teeth were imaged using a fluorescent capturing system. All the lesions were located on the gingival third of the teeth. One examiner undertook two analyses of the images 1 week apart and another examiner undertook a single analysis. Analyses were undertaken using QLF 2.00 g with four patch borders. Each border was assessed as active or inactive. QLF metrics DeltaF, DeltaQ and area were exported. Kappa statistics were used to measure the agreement of border inclusion between all three analyses, and intra-class correlation coefficients (ICCs) were used to determine the intra- and inter-examiner reliability of the QLF metrics. Agreement on border exclusion was poor; with intra-examiner kappa of 0.48 and inter-examiner at 0.20. However, despite the inconsistencies in border exclusions the ICCs for each QLF metric were high; intra-examiner DeltaQ 0.91, DeltaF 0.80 and area 0.92; inter-examiner DeltaQ 0.86, DeltaF 0.68, area 0.88. Lesions adjacent to the gingival margin will often require a patch analysis border to be excluded in order to ensure a satisfactory reconstruction and thus accurate analysis. The decision to include or exclude a border and, if excluded, which border to select appears to be highly variable between examiners. Nevertheless, the QLF metrics appear to be robust as demonstrated by the high ICCs noted in this study.  相似文献   
954.
This study compared the bacterial community profiles of the microbiota associated with acute apical abscesses from Brazilian and USA patients using denaturing gradient gel electrophoresis (DGGE). DNA was extracted from purulent exudate aspirates and part of the 16S rRNA gene was amplified by polymerase chain reaction and separated by DGGE. The resulting banding patterns, which were representative of the bacterial community structures in samples from the two locations, were then compared. Distinct DGGE banding patterns were observed from different samples. Ninety-nine bands with distinct positions in the gels were detected, of which 27 were found only in the USA samples and 13 were exclusive to Brazilian samples. Four of the 59 shared bands showed very discrepant findings with regard to prevalence in the two locations. Cluster analysis of DGGE banding profiles showed a great variability in the bacterial populations associated with teeth with abscesses regardless of the geographical location. Two big clusters, one for each location, were observed. Other clusters contained a mixture of samples from the two locations. The results of the present study demonstrated a great variability in the bacterial community profiles among samples. This indicates that the bacterial communities of abscesses are unique for each individual in terms of diversity. The composition of the microbiota in some samples showed a geography-related pattern. Furthermore, several bands were exclusive for each location and others were shared by the two locations and showed great differences in prevalence.  相似文献   
955.
The purpose of this paper is to discuss the treatment required for a patient affected by chronic maxillary sinusitis following a sinus grafting procedure with an alloplastic material. Sinusitis was not the consequence of migration of alloplastic material into the maxillary sinus, but rather the consequence of overfilling the subantral space followed by obstruction of the ostium. The treatment involved removal of the alloplastic material and correction of the ostium obstruction via a nasal endoscopic approach.  相似文献   
956.
957.
A case of angioleiomyoma localized at the level of the soft palate is reported. The 31-year-old patient presented a non-pathognomonic clinical picture and the anamnestic finding of the relatively slow growth of the neoformation raised problems of differential diagnosis in relation to benign growth and lesion of a non-neoplastic nature. The differential diagnosis was only obtained with histological examination of biopsy material.  相似文献   
958.
Dentists are a potentially valuable source of community education about the health effects surrounding tobacco use. The aims of this study were to provide Australian data on dentists' current practice regarding discussing smoking with patients, dentists' perceptions of the barriers to discussing smoking with patients and dentists' interest in discussing smoking with patients. A postal survey of all dentists who were members of the Hunter Branch of the Australian Dental Association in New South Wales was conducted. Dentists generally reported quite high levels of current activity regarding smoking. The majority of dentists reported asking at least some of their patients whether or not they smoked. Dentists reported that they discussed the possible oral effects of smoking with at least some of their smoking patients. Furthermore, they told at least some of their patients with smoking related disease that smoking may have contributed to their problems. Dentists identified a number of difficulties involved in helping patients quit smoking. These findings may be used to help guide future research and practice in involving dentists further in discussing smoking with patients.  相似文献   
959.
Simple three point bending tests were performed on Ni-Ti wires with three different Af points (1 degree C, 13 degrees C and 34 degrees C) to clarify the relationship between Af temperature and load changes under constant deformation. Each wire was deformed at 37 degrees C and then thermal changes were imposed by temperatures of 2 degrees C or 60 degrees C. The load changes with thermal changes from 37 degrees C to 2 degrees C or 60 degrees C showed the same tendency on the wires with different Af points: In the loading stage, the load became lower than the initial level at 37 degrees C and in the unloading stage, the load became higher than the initial load. The largest load change in the unloading stage was measured with the 13 degrees C Af point wire. Care must be taken when handling Ni-Ti wire with an Af point of less than 1 degree C in order to prevent it from reaching the limit of critical stress of slip deformation when the temperature in the mouth rises to above 40 degrees C.  相似文献   
960.
Cranio-orbital-temporal neurofibromatosis is an uncommon subtype of neurofibromatosis 1 characterized by pulsatile exophthalmos, orbital neurofibromas, sphenoid wing dysplasia, expansion of the temporal fossa, and herniation of the temporal lobe into the orbit. The cause of the sphenoid wing dysplasia is uncertain. Reconstruction of the sphenoid defect, separating the orbit and cranial vault, has been problematic because of resorption of bone grafts. This reports illustrates one potential cause of the sphenoid defect and a possible cause of the bone graft resorption.  相似文献   
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