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Objective Pegylated-interferon monotherapy is the standard treatment for patients with chronic hepatitis B; however, the factors associated with its therapeutic effects remain unclear. Methods Patients with chronic hepatitis B were treated with pegylated interferon α-2a for 48 weeks. We evaluated the kinetics of hepatitis B surface antigen (HBsAg) during treatment and follow-up periods and the factors associated with an HBsAg response (defined as a change in HBsAg of ≥-1 log IU/mL from baseline). Results The study population comprised 50 patients. The median baseline levels of hepatitis B virus DNA and HBsAg were 5.00 and 3.40 log IU/mL. The median values of HBsAg reduction from baseline were -0.44 (n=48), -0.41 (n=40), and -0.68 (n=11) log IU/mL at the end of treatment and at 48 and 144 weeks post-treatment, respectively. The rates of HBsAg response were 24.0% and 22.5% at the end of treatment and at 48 weeks post-treatment, respectively. A multivariate analysis identified HBsAg <3.00 log IU/mL as an independent baseline factor contributing to the HBsAg response at the end of treatment and 48 weeks post-treatment (p=1.07×10-2 and 4.42×10-2, respectively). There were significant differences in the reduction of the HBsAg levels at 12 weeks of treatment and in the incidence of serum ALT increase during treatment between patients with and without an HBsAg response. Conclusion These findings suggest that the baseline HBsAg level, HBsAg kinetics at 12 weeks of treatment, and ALT increase during treatment are important factors contributing to the HBsAg response in pegylated interferon α-2a monotherapy for patients with chronic hepatitis B.  相似文献   
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The aim of this study was to identify and compare the attitudes of dental students toward their career choice and dental education in three different countries. Three hundred thirty-six dental students from the University of British Columbia, Canada; Mahidol University and Chiang Mai University, Thailand; and Nippon Dental University, Japan, participated in this study. Information was derived from a questionnaire consisting of career choice items and dental education items. Significant differences in the responses of the participants from each of the three countries were detected for each of the questionnaire items (P<0.001). Regarding factors that may have served as motivations for career choice, the majority of dental students from each country indicated positive reasons such as interpersonal motives, caring for other people, and academic interest. For future career options, the majority of Japanese and Canadian students planned to work as general dentists. Thai students were more likely than Japanese or Canadian to prefer specialization than practicing general dentistry. Nearly three-quarters of the Canadian and Thai students were satisfied with the teaching faculty of their schools, while only a quarter of the Japanese students indicated satisfaction. The findings from this study enhance our understanding of differences and/or similarities among dental students in three nations; this information may help to define strategies to improve the quality of international student exchange programs.  相似文献   
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Object The purpose of this study was to compare the efficacy of the four combination modes of Trophy RadioVisioGraphy UI sensor (Trex-Trophy Radiology Inc., Marne-la-Valee, France) and Kodak InSight film (Eastman Kodak Co., Rochester, NY) for detecting proximal dental caries. Materials and Methods Thirty extracted human upper premolars were selected. Of 60 surfaces, 25 had carious lesions in the form of small cavities, and the rest showed no evidence of caries as verified by a micro computed tomogram (micro CT; XCT Research SA+, Stratec Medizintechnik GmbH, Pforzheim, Germany). All teeth were radiographed with the paralleling technique (60kV, 40 cm focus-to-sensor distance). Four combination modes (high-resolution caries mode—HRC; high-sensitivity caries mode—HSC; high-resolution periodontal mode—HRP; and high-resolution endo mode—HRE) were used. Exposure was set at 0.12 sec for HRC, 0.08 sec for HSC, 0.16 sec for HRP, 0.12 sec for HRE, and 0.16 sec for the Kodak InSight film. The resulting images were evaluated by three oral radiologists. The same three observers evaluated the digital images, and were allowed to use the contrast and brightness controls in doing so. Possible differences in ROC curve areas among image modalities were assessed by the Friedman test. Results The mean ROC curve areas were 0.66±0.11 for HRC, 0.78±0.02 for HSC, 0.76±0.04 for HRE, 0.77±0.04 for HRP, and 0.71±0.09 for the Kodak InSight film. There were no statistically significant differences between HRC, HSC, HRE, HRP and the Kodak InSight film in terms of proximal caries detection. Conclusion The four modes of RVG UI system are each a viable alternative to intraoral film for the detection of incipient dental caries.  相似文献   
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PURPOSE: The use of osseointegrated implants for maxillofacial prostheses reduces the need for adhesives, provides for a more stable and more esthetic prosthesis with thinner margins, and results in increased patient acceptance and confidence. The purpose of this study was to compare the retention and load transfer characteristics of differently designed implant-retained auricular prostheses. MATERIALS AND METHODS: A photoelastic model was fabricated of the auricular-temporal region of a human skull. Craniofacial implants 3.75 mm in diameter and 4 mm long were embedded in locations typically selected to retain auricular prostheses. Two retention mechanisms were evaluated on the implants: a Hader bar with 3 clips and the use of 3 Locator attachments. The retentive capacity of the prostheses was determined on an Instron test machine. Initial retention and changes with multiple removals were examined. Dislodgment forces were applied to each retentive device in the field of a circular polariscope. Resulting stresses were monitored and recorded photographically. RESULTS: The highest initial retention demonstrated by the Locator device was 12.4 +/- 0.9 lb, and the highest retention value for the Hader bar with clips was 7.5 +/- 1.1 lb. All attachments decreased in retention after multiple removals. The Locator devices produced higher peri-implant stresses compared to the Hader bar-with-clips design. CONCLUSIONS: Since higher retention is associated with higher stresses, results of this study suggest that a balance between retention and stress production is necessary in selecting a retention mechanism for the specific requirements of the patient being treated. The Locator attachment was correlated with higher retention values as well as with higher peri-implant stress compared to the Hader bar-and-clip attachment design. Retention decreased and then stabilized after multiple  相似文献   
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Background

Erythropoiesis-stimulating agents (ESAs) are standard therapy for chronic kidney disease (CKD) patients with renal anemia. However, few studies have compared the effects of different ESAs on anemia in identical pre-dialysis CKD patients.

Methods

Seventy-nine patients who switched from epoetin beta to darbepoetin alfa (Group 1), and 82 patients who switched from darbepoetin alfa to epoetin beta pegol (Group 2) were enrolled in this study. Clinical and laboratory parameters were assessed for 6 months before and after switching ESAs. The prevalence of adverse events, the dose conversion ratio of ESAs, and the frequency of ESA administration were also analyzed.

Results

Analysis of variance showed that switching ESAs did not significantly change hemoglobin levels for the study duration in both groups (mean hemoglobin 10.3–10.5 g/dL in Group 1 and 10.4–10.7 g/dL in Group 2). Estimated glomerular filtration rate, blood pressure, transferrin saturation, ferritin, and albumin remained constant in both groups. The prevalence of adverse effects was quite low (0–3.8 %) during both 6-month study periods. The mean dose conversion ratio for epoetin beta:darbepoetin alfa was 163.7 units:1 μg and for darbepoetin alfa:epoetin beta pegol was 1.08 μg:1 μg. The intervals of ESA administration significantly differed (epoetin beta pegol > darbepoetin alfa > epoetin beta).

Conclusions

Epoetin beta, darbepoetin alfa, and epoetin beta pegol are effective and well-tolerated agents for managing anemia in Japanese pre-dialysis CKD patients. The intervals of ESA administration to maintain a patient’s target hemoglobin were longer in the order of epoetin beta pegol > darbepoetin alfa > epoetin beta.  相似文献   
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Background

Ischemic postconditioning (PostC) protects the liver against ischemia-reperfusion (IR) injury. Milrinone, a phosphodiesterase 3 inhibitor, has been reported to exhibit preconditioning properties against hepatic IR injury; however, its PostC properties remain unknown. This study investigated whether milrinone has PostC properties against hepatic IR injury and the roles of phosphatidylinositol 3-kinase (PI3K) and nitric oxide synthase (NOS).

Materials and methods

Male Wistar rats were separated into six groups: (1) group S: animals that underwent sham operation without ischemia, (2) group C: ischemia followed by reperfusion with no other intervention, (3) group M: milrinone administered immediately after reperfusion, (4) group MW: wortmannin, a PI3K inhibitor, injected before milrinone administration, (5) group MN: l-NAME, a NOS inhibitor, injected before milrinone administration, and (6) group MD, milrinone administered 30 min after reperfusion. Except for group S, all groups underwent 1 h of warm ischemia of median and left lateral lobes, followed by 5 h of reperfusion. Biochemical liver function analysis and histologic examination were performed.

Results

Serum aspartate aminotransferase, alanine aminotransferase, and lactic dehydrogenase levels, histologic damage scores, and apoptotic rate in group M were significantly lower than those in group C. The inhibition of PI3K or NOS prevented this protective effect. Milrinone administered 30 min after reperfusion did not show obvious protective effects.

Conclusions

Milrinone-induced PostC protects against hepatic IR injury when it is administered immediately after reperfusion, and PI3K and NOS may play an important role in this protective effect.  相似文献   
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