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991.
Impaction grafting allows restoration of bone stock in hip revision, but there are reports of massive early subsidence. The aim of this study was to determine prognostic factors for stem and cup migration in a group of 56 consecutive patients followed up from 1 to 5 years. Cup and stem migration was correlated with 13 predictors including stem design, stem positioning, femoral anatomy, patient characteristics, and bone graft density. All migration occurred mainly during the first 3 months after surgery. Stem alignment changed by an average of 4.8 degrees . Fifty percent of the change in stem alignment was explained by four variables: age, femoral diameter, stem design, and density of the graft at the tip of the stem. Stem subsidence averaged 2.7 mm, and cup migration averaged 3.0 mm. None of the predictors explained the wide variation of migration of the cup or distal migration of the stem. It may be necessary to determine implant stability at the time of surgery.  相似文献   
992.
993.
994.
Farming is acknowledged to be a dangerous occupation that poses risks for farmers, farm employees and family members. This paper explores the farm as a setting where health promotion and prevention programs can be implemented. We present data from an occupational health and safety needs assessment of 347 farms in the South Central region of the province of Alberta, Canada. The data are used to describe farmers' familiarity with farm living, thoughts on farm safety, the numbers of people working and types of work performed, other work, income, and the availability of resources. Results are discussed in terms of implications for practitioners under three proposed justifications for a settings model. Data revealed that there is so much heterogeneity among these farms that an ecological settings approach to program development that accounts for both the composition and context of rural settings is more appropriate than the settings model currently in use.  相似文献   
995.
BACKGROUND AND AIM: There are only little data about the effects of lipid-lowering drugs (LLDs) on the metabolism of essential n-6 and n-3 fatty acids in patients with established coronary heart disease (CHD). METHODS AND RESULTS: Male patients with CHD and high cholesterol levels (>6.2 mmol/L) were randomized (double-blind protocol) to receive either simvastatin 20mg (S) or fenofibrate 200mg daily (F) for 3 months. Dietary habits and plasma fatty acids were not different in the two groups at baseline. After treatment, there were significant changes in both the groups for the main n-6 fatty acids, with an increase in arachidonate (from 6.5+/-1.7% of total fatty acids to 7.5+/-2.1, p<0.001 in S and from 6.2+/-1.4 to 6.8+/-1.4, p<0.005 in F) and a decrease in linoleate (from 26.9+/-3.9 to 24.2+/-3.6, p<0.001, and from 27.8+/-3.4 to 26.1+/-4.2, p<0.05, in S and F, respectively). In addition, there was a decrease in two major n-3 fatty acids (alpha-linolenate and docosahexanoate, both p<0.05), but only in F. CONCLUSIONS: For the first time in a double-blind randomized study in CHD patients, we report that LLDs significantly alter the metabolism of essential fatty acids that are critically important for the pathogenesis and prevention of CHD. Further studies are urgently needed to examine the effects of higher dosages of statins (as currently proposed to reduce more cholesterol) on these essential fatty acids in the clinical setting and the crucial questions of whether specific dietary intervention (combining low intake of n-6 fatty acids and high intake of n-3 fatty acids) may improve the effectiveness of these drugs.  相似文献   
996.
In100, a new integron carrying a carbapenemase gene (bla(VIM-2)) associated with a carbenicillinase (blaP1b) and aminoglycoside resistance genes (aacA4 and aadA2), was detected in a Pseudomonas aeruginosa clinical isolate. The particular gene cassette organization of In100 seems to reflect the evolution of antibiotic usage in therapeutics.  相似文献   
997.
Anatomic knowledge on the zygomatic fossa is of primary importance to improve the regional anesthetic technique of the maxillary nerve. Few reports in the literature have addressed the trajectory of the maxillary nerve and its branches in this region; thus, this study aimed at presenting information about the trajectory of these nerves. Thirty human half-heads of both genders were fixed in 10% formalin and demineralized in 5% nitric acid, and the maxillary nerve was dissected since its origin on the pterygopalatine fossa until penetration into the inferior orbital fissure. It was observed that the maxillary nerve sends one to three posterior superior alveolar branches and tuberal descendent branches, which supply the soft tissue structures of the region. The posterior superior alveolar nerves are inferiorly oriented near the maxillary tuberosity, where they penetrate the alveolar canals with the posterior superior alveolar artery and send small nerve branches that continue in an extraosseous trajectory. This study found that nearly 2/3 of the trajectory of the maxillary nerve is located in the zygomatic region, with a short segment (1/3) in the pterygopalatine fossa.  相似文献   
998.
Dental fear is often associated with experience of pain, unpleasant sounds and uncomfortable vibrations caused by dental drills. Therefore patients welcome alternative, less painful excavating methods such as lasers, sandblasters and chemomechanical systems. The aim of this study was to compare a chemomechanical caries removal system (Carisolv) to traditional drilling with regard to patient acceptance and time consumption as well as the six-month success rate of fillings. Ninety-two primary teeth in 46 children were included in the study. From this study, the following conclusions can be drawn: patient acceptance of Carisolv-treatment compared to drilling is excellent, since 65% would choose Carisolv and no one drilling when treated next time. The dentists rated patients' degree of pain significantly lower in Carisolv situations than in drill situations. Time consumption is significantly higher when excavating with Carisolv (6.7 min.) than with drill (3.3 min.). The durability of fillings six months after treatment is equal in the two groups.  相似文献   
999.
The present study assessed condylar displacement between initial maximal habitual intercuspation (MHI) and centric relation (CR), recorded after using a deprogramming occlusal splint for an average period of 7.8 +/- 2.1 months prior to any orthodontic treatment. The sample consisted of 22 subjects, 11 male and 11 female, with an average age of 14.2 +/- 1.4 years, with Class II malocclusion and with no apparent signs or symptoms of temporomandibular dysfunction (TMD). Condylar displacement was measured using a Panadent axis position indicator in decimal fractions of a millimeter. The original mean vertical displacements and the corresponding standard deviations were 4.24 +/- 2.53 mm and 3.86 +/- 2.72 mm, respectively, for the right and left sides. Because a significant negative correlation was observed between original condylar displacements and age factors, the displacement values were statistically adjusted to 2.74 +/- 2.00 mm and 2.44 +/- 1.93 mm. On the horizontal plane, the mean displacements measured were -0.72 +/- 1.53 mm on the right side and -0.51 +/- 1.98 mm on the left. The mean displacement on the transversal plane was 0.03 +/- 0.87 mm. A comparison between these values and those observed in non-deprogrammed groups, as well as those published in the related literature, indicates that use of occlusal splints results in greater mean condylar displacement values, especially vertically, between CR and MHI positions, which contributed to a more accurate orthodontic diagnosis.  相似文献   
1000.
This study has defined the cephalometric values of the Craniofacial Analysis of the Tweed Foundation for a sample of Brazilian subjects. The sample consisted of 211 cephalometric radiographs from subjects aged 12-15, which were divided into two groups: Class II group, with 168 lateral teleradiographs (cephalograms) of white Brazilian subjects, with Angle Class II, division 1 malocclusion, of both genders (82 males and 86 females); and the Control Group, with 43 lateral teleradiographs (cephalograms) of subjects whose occlusion was clinically excellent, and also of both genders (21 males and 22 females). The teleradiographs were selected from the files of the Department of Orthodontics, School of Dentistry of Piracicaba, State University of Campinas, previously to the orthodontic treatment. The results demonstrated no sexual dimorphism for each group, as attested by the Student's t-test. The exploratory analysis (+/- 0.5 standard deviation) enabled the tolerance limits to be determined and a Craniofacial Analysis Table to be constructed using the respective cephalometric intervals. In addition, the difference between the two groups was not statistically significant according to the maxilla position. The maxilla was in a good position in relation to the cranial base. On the other hand, the mandible was retruded in relation to the cranial base in the Class II cases. The skeletal pattern was not defined because only the Facial Height Index (FHI) showed a vertical pattern in Class II subjects, while the Y Axis, SN.PlO, SN.GoMe and FMA values did not show any statistically significant difference between the groups. The Class II division 1 subjects showed lower incisors more labially tipped and a convex facial profile.  相似文献   
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