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31.
BACKGROUND: The aim of the present study was to investigate the importance of stress for the development of periodontitis by comparing oral health status, proinflammatory markers, and cortisol in gingival crevicular fluid (GCF) and saliva in patients with stress-related mental depression and controls. METHODS: The participants consisted of 43 women with stress-related depression and exhaustion (Diagnostic and Statistical Manual of Mental Disorders, 4th edition [DSM-IV], with a mean age of 42.0 (+/- 9.3 SD) years, and 29 controls, with a mean age of 54.5 (+/- 2.9 SD) years. Clinical examination included the assessment of dental plaque, gingival inflammation (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and number of teeth. GCF was collected with an intracrevicular washing technique from four sites in each subject. Interleukin (IL)-1beta, IL-6, and matrix metalloproteinase-9 were determined with enzyme-linked immunosorbent assay and cortisol with radioimmunoassay (125I RIA). Analysis of covariance (one-way covariance analyses) was used to remove the influence of age and smoking. RESULTS: The amount of plaque was significantly higher in patients compared to controls (P<0.003). The patients had an average GI of 1.53 (+/-0.13 SD) compared to 0.89 (+/- 0.10 SD) for the controls (P< 0.001). The levels of cortisol in GCF was significantly higher in patients than in controls, 3.46 nmol/l (+/- 3.25 SD) and 0.30 nmol/l (+/- 0.25 SD), respectively (P<0.001), whereas cortisol in saliva did not differ between groups. The levels of IL-6 in GCF were significantly higher in the patients than in controls (P<0.05). CONCLUSION: Women with stress-related depression and exhaustion had more plaque accumulation, GI and increased levels of IL-6 and cortisol in GCF compared to normal controls, suggesting that depression might affect immune function, which could lead to impaired periodontal health.  相似文献   
32.
The reported skew distribution of caries prevalence in preschool children, with a small group of children with very high caries prevalence, stresses the importance of early identification for prevention.The present study aimed to describe the caries prevalence in a group of Swedish preschool children and to identify caries risk factors in this population. 221 children, 2 to 3 years old, agreed to participate in the study (82%). A standardized questionnaire was used to describe socio-economic factors, dietary and oral hygiene habits and exposure to fluoride. Initial and manifest dental caries was diagnosed and the presence of plaque was visually observed without disclosing solution. Saliva and plaque samples were collected for identification of mutans streptococci (MS). For statistical analysis,the Student's t-test,the Chi-square test and Fisher's exact test were used. The caries prevalence among the 2 to 3 year-olds was 7 and 18 percent respectively. An association between early childhood caries and a number of factors was found e.g. the presence of MS and visible plaque, nocturnal meals, frequent sugar consumption, mothers' state of employment and immigrant background. The Public Dental Health Service has been successful in decreasing the number of children with caries, but the challenge remains to be able to control caries in the high-risk group. The skew distribution, with many children without caries and a smaller group with very high caries prevalence, was confirmed.The study provided insight into various factors, useful for monitoring children at risk of developing early childhood caries.  相似文献   
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34.
Optimum force magnitude for orthodontic tooth movement: a mathematic model.   总被引:9,自引:0,他引:9  
The aim of this study was to develop a mathematic model to describe the relationship between magnitude of applied force and rate of orthodontic tooth movement. Initially, data were extracted from experimental studies in dogs (beagles), in which controlled, standardized forces were used to move mandibular second premolars distally. Curve-fitting by nonlinear regression analysis provided an equation describing the relationship between force magnitude and rate of tooth movement in beagles. A similar equation was subsequently used to analyze the limited available data from the literature on human canine retraction. The maximum rates of tooth movement in humans and dogs are very similar. A threshold for force magnitude that would switch on tooth movement could not be defined. The model showed that a wide range of forces can be identified, all of which lead to a maximum rate of tooth movement.  相似文献   
35.
We hypothesized that one mechanism underlying advanced periodontal disease in diabetes may involve oxidant stress in the gingiva, induced by the effects of Advanced Glycation Endproducts (AGEs), the irreversible products of non-enzymatic glycation and oxidation of proteins and lipids which accumulate in diabetic plasma and tissue. Infusion of AGE albumin, a prototypic ligand, into mice resulted in increased generation of thiobarbituric acid reactive substances (TBARS) compared with infusion of non-glycated albumin in the gingiva, as well as in the lung, kidney and brain. Pretreatment of the animals with the antioxidants probucol or N-acetylcysteine (NAC) prevented the generation of TBARS in the gingiva. Affinity-purified antibody to AGEs demonstrated increased immunoreactivity for AGEs in the vasculature and connective tissues of the gingiva in streptozotocin-induced diabetic mice compared to non-diabetic controls. Increased immunoreactivity for AGEs was also demonstrated in the gingiva of diabetic humans compared with non-diabetic individuals via immuno-histochemistry and ELISA. Consistent with these data, immunohistochemistry for heme oxygenase-1, a marker of enhanced oxidant stress, was increased in the gingival vasculature of diabetic mice and humans compared with non-diabetic controls. These data suggest that AGEs present in diabetic gingiva may be associated with a state of enhanced oxidant stress, a potential mechanism for accelerated tissue injury.  相似文献   
36.
37.
AIM: The aim of this study was to evaluate spontaneous space closure, development of the permanent dentition, and need for orthodontic treatment after extraction of permanent first molars due to severe molar-incisor hypomineralization (MIH). SUBJECTS: Twenty-seven children aged 5.6-12.7 (median 8.2) years had one to four permanent first molars extracted due to severe MIH. Each case was followed up on individual indications 3.8-8.3 (median 5.7) years after extractions. The eruption of the permanent dentition, and space closure were documented by orthopantomograms, casts, photographs, and/or bitewings. RESULTS: Fifteen children were judged to have a favourable spontaneous development of their permanent dentition without any orthodontic intervention. Seven children were or should be subjected to orthodontic treatment for other reasons registered prior to the extraction. Five children were judged to have a treatment at least caused by the extractions, but three of them abstained because of no subjective treatment need. CONCLUSION: Extraction of permanent first molars severely affected by MIH is a good treatment alternative. Favourable spontaneous space reduction and development of the permanent dentition positioning can be expected without any intervention in the majority of cases extracted prior to the eruption of the second molar.  相似文献   
38.
Abstract –  Trauma to the primary dentition present special problems and the management is often different as compared with permanent teeth. An appropriate emergency treatment plan is important for a good prognosis. Guidelines are useful for delivering the best care possible in an efficient manner. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases in which the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the current best evidence based on literature research and professional opinion. In this third article out of three, the IADT Guidelines for the management of traumatic injuries in the primary dentition, are presented.  相似文献   
39.
This is the fifth paper in a series on the prescribing of medicines for children by dentists working in primary dental care. It deals with conscious sedation for children.  相似文献   
40.
AIMS: Arthrogryposis multiplex congenita (AMC) is characterized by congenital contractures and joint deformities, but there are only a few reports of temporomandibular joint (TMJ) involvement. The objective of this investigation was to study the cause of limited mouth movement in this disease. MATERIALS AND METHODS: Four individuals from a family affected by AMC over 5 generations were examined clinically and by magnetic resonance imaging (MRI) and 3-dimensional computerized tomography (3D-CT). RESULTS: The CT scans of the 4 individuals showed hyperplasia of the coronoid process protruding into the infratemporal fossa in 2 of them and cranially to the zygomatic arch in the other 2; the hyperplasia was associated with mechanical limitation of the mouth opening. The MRI showed a disc displacement with reduction in 1 patient and a disc displacement without reduction in another; disc displacement could not be evaluated because of the limited mouth opening in the other 2. The condyle-disc complex of these last 2 individuals could only rotate. The MRI on T2-weighted images showed disc hyposignal in all cases but no alterations in the masticatory muscle tissue. The pedigree of the family suggests an autosomal dominant form of inheritance. CONCLUSIONS: The restriction of mouth opening in the 4 individuals affected by AMC was likely due to osseous dysplasia.  相似文献   
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