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31.
32.
Two cases of fibrous defect (nonossifying fibroma) of the mandible are presented. Each case occurred in the mandibular ramus of an 11-year-old girl. The usual fibrous defect of bone is an intraosseous fibrous, nonneoplastic, reactive lesion which appears as a well-delineated defect in the metaphysis of long bones. This report reviews the literature, histopathology, and classification of the fibrous defect of bone.  相似文献   
33.
Stimulation of muscarinic cholinergic receptors on rat parotid acinar cells causes a rapid production of inositol phosphates, with the key metabolic event being the breakdown of phosphatidylinositol 4,5-bisphosphate into inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) and diacylglycerol. Here a high-performance liquid chromatographic technique was used to measure the effects of intracellular lithium ions on the amount of various inositol phosphates produced. When acini were stimulated maximally with acetylcholine (ACh), the sum of all inositol phosphates produced followed a monoexponential function with a production rate constant for Ins(1,4,5)P3 of 0.07 +/- 0.01 solidus/sec. The presence of 23 mM LiCl intracellularly reduced the production rate constant of Ins(1,4,5)P3 induced by ACh to 0.03 +/- 0.01 solidus/sec, resulting in a decrease in the Ins(1,4,5)P3 production as well as in the magnitude of the rise in the intracellular free Ca2+ concentration. The lithium ion (Li+) did not affect the rate of conversion of Ins(1,4,5)P3 to either inositol 1,4-bisphosphate or inositol 1,3,4,5-tetrakisphosphate. The rate of the inositol phosphate production after the addition of the Ca2+ ionophore ionomycin was unaffected by intracellular Li+ (23 mM), which implies that the action of Li+ was at the muscarinic cholinergic receptor, on G-protein or on the interactions between G-proteins and phospholipase C. Thus, in the early events after receptor stimulation with ACh, Li+ causes a reduction in the concentration of the cellular messengers Ins(1,4,5)P3 and Ca2+.  相似文献   
34.
The aim of this paper was to describe a method for the preparation of autologous fibrin glue with platelet growth factors and to report its use with particulate cancellous bone in reconstructive maxillofacial surgery. The fibrin glue is a two-component glue, where the one component is a concentrated fibrinogen solution with platelet growth factors and the other component is a thrombin solution. Both components were produced from the patients own blood, thus making the glue entirely autologous. The glue was prepared from platelet rich plasma separated from 200 ml of the patient's blood prior to the operation. The fibrinogen in the glue was precipitated from the platelet rich plasma by ethanol precipitation at low temperature and separated together with the platelets by centrifugation. Raising the temperature to 37 degrees C redissolved the precipitate. The thrombin solution in the glue was produced from prothrombin precipitated from 10 ml of the platelet rich plasma by lowering the pH and the ionic strength. The precipitate was separated by centrifugation and dissolved in a calcium ion solution. Increasing the pH to neutral value induced activation to thrombin. Preparation of the fibrin glue was performed in the blood bank within 60 to 90 min with the use of standard equipment. The outcome from 200 ml of blood was approximately 8 ml of fibrin glue: 6 ml fibrinogen to be coagulated with 2 ml of thrombin. The glue had a fibrinogen concentration of approximately 12 times the value in platelet rich plasma and the concentration of growth factors was approximately eight times the value in platelet rich plasma. We have used this glue successfully with particulate bone grafts for reconstructive purposes within the oral and maxillofacial field. It might as well be applied to other surgical areas. Whenever larger amount of the glue will be needed, a whole unit of blood may be taken from the patient, and the red cells re-transfused to the patient during or after the operation.  相似文献   
35.
Kay EJ  Ward N  Locker D 《British dental journal》2003,194(11):621-5; discussion 611
OBJECTIVE: To measure the subjective impact of oral health in a group of patients attending general dental practices in the North West of England and to investigate the attributes of dentists and practices in order to examine how such attributes might relate to patients' subjective perceptions of oral health. DESIGN: Fifteen general dental practices conducting a simultaneous survey of attending patients and 15 practitioners from these practices providing information about their attitudes to treatment, prevention and various aspects of their surgery. SETTING: General dental OUTCOME MEASURES: Patient subjective impact scores. Relationships between practice and practitioner variables and patients' subjectively perceived oral health. RESULTS: Fifteen practitioners with diverse practice attributes provided data on 718 patients. The mean total oral health impact score was 18.4. Twenty two per cent of patients had experienced pain in the four weeks before the survey and 11% had been unable to chew some foods. Fifty five per cent of the surveyed population had, in the previous year, worried about the appearance of their mouth and 65% had worried about their oral health in general. Dentists' beliefs were related to patient impact scores but practice attributes were not significantly associated with patients' impacts. CONCLUSIONS: Fourteen percent of the differences in patients' subjectively perceived oral health can be attributed to dentist attitudes and attributes. Further research regarding the influence of dentists personality and professional beliefs on patients well-being needs to be undertaken.  相似文献   
36.
DESIGN: This was a randomised controlled trial (RCT) set in a dental hospital. INTERVENTION: The implant group (IG) had two implants placed in the interforaminal region of the lower jaw followed (after healing) by a denture fixed to the implants by a ball attachment mechanism. In the conventional dentures group (CG), dentures were constructed using conventional replacement denture techniques. Patients in the IG had conventional upper dentures made in the same fashion. OUTCOME MEASURE: The performance of the dentures was evaluated using an oral health impact profile (OHIP) and a denture satisfaction scale before treatment and 3 months post-treatment. RESULTS: Analysis was conducted on an intention-to-treat basis. Substantial improvements in oral-health-related quality of life and denture satisfaction were reported by both groups. There were, however, no significant differences post-treatment between the groups. Patients randomised to the IG who declined implants had significantly lower pretreatment OHIP scores and there were significantly greater pre-/ post-treatment change-scores for individuals who had implants compared with the change-scores of people who declined. CONCLUSIONS: There were no significant post-treatment differences between the groups, but a treatment effect may be masked by the intention-to-treat analysis. The pre-/ post-treatment OHIP change-scores were significantly greater for people receiving implants than for those who refused.  相似文献   
37.
AIM: To assess the adoption of new endodontic technology in a population of Danish practitioners. METHODOLOGY: Members of the Copenhagen Dental Association (n = 1156) were approached with a questionnaire concerning the frequency of various endodontic procedures. Three options were available: often, occasionally and never. Responses were anonymous. The statistical analyses were performed as studies of association in two- or three-way contingency tables, and with Goodman-Kruskal's gamma-coefficient as the basic tool chosen. RESULTS: Only data from general practitioners (GPs) in private practice were analysed (n = 956). The response rate was 72%. NiTi hand instruments were often used to negotiate canals by 18%, whilst 10% often used NiTi rotary systems. Electronic apex locators were often employed by 15%. Nineteen per cent reported that warm gutta-percha was often used. A majority (53%) often spend two sessions to instrument a molar, and 20% often needed three or more sessions to finish the shaping phase. To complete a treatment of a nonvital case most practitioners reported to use at least three appointments. Only 4% frequently applied rubber dam. CONCLUSIONS: The adoption of new endodontic technology is at an early stage amongst Danish GPs. A new revised remuneration system might influence the rate of adoption, allowing the practitioners to act more rationally and produce a higher frequency of good-quality root fillings. Progress towards high quality endodontics might be hindered by the nonuse of rubber dam.  相似文献   
38.
The results of a follow-up study on 84 patients treated by mandibular vestibulolingual sulcoplasty with skin grafting, based on a questionnaire and clinical examination, are reported. It was concluded that more than 80% of the patients were satisfied with the results and that the complaints from the remaining patients were of only minor importance.  相似文献   
39.
AIM: To test the hypothesis that Coltosol F might cause infractions and cusp fracture in root-filled teeth because of material expansion. METHODOLOGY: Thirty-two extracted human molar teeth were root filled and prepared with mesial-occlusal-distal (MOD) cavities with or without undercuts. The specimens were filled proximally with glass-ionomer cement and then occlusally with either Coltosol F or zinc oxide eugenol (ZOE). The tooth specimens were kept in water at 37 degrees C for a period of 20 days, and every second day the intercusp distance (ICD) of each specimen was measured in a travelling microscope, and the number of infraction lines as well as fractures were noted. RESULTS: The number of infraction lines increased in teeth filled with Coltosol F. Between day 8 and 16, seven of 16 teeth filled with Coltosol F showed fracture and exhibited a mean increase in ICD of 316 +/- 156 microm. Teeth filled with ZOE did not show an increase in number of infraction lines or in ICD, and none showed fracture. CONCLUSIONS: The hygroscopic expansion of Coltosol F in a cavity may lead to cusp deflection, infraction development and fracture. Masticatory forces will in vivo aggravate this unfavourable condition. The material is not recommended for temporary filling in root-filled teeth except for a few days.  相似文献   
40.
The aim of this study was to develop, and assess the inter-observer reliability of an instrument for evaluating dental students' communication skills. Methods used were process-tracking of interactions between experienced practitioners and patients, development of the instrument and its simultaneous use by two researchers observing 43 third year dental students prior to communication skills training. The results found that the instrument was appropriate for the purpose for which it was designed, and was easy to utilise. There were no significant differences between observers' total scores. Item-specific weighted kappa scores showed almost perfect agreement between observers for all but four of the 31 items. The lowest interobserver weighted kappa score was for the measurement of eye contact (k = 0.60). In conclusion, assessment of communication skills is now a necessity in the undergraduate curriculum. Preliminary analysis of an instrument of communication skills in the dental surgery indicates that it may be possible to do this reliably.  相似文献   
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