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1.
C. O. Onyeaso BDS FWACS M. O. Arowojolu BDS FWACS J. O. Taiwo BDS MSc DDPH RCS Eng 《American journal of orthodontics and dentofacial orthopedics》2003,124(6):714-720
This prospective clinic-based study evaluated the pretreatment periodontal status of the orthodontic patients seen at the University College Hospital, Ibadan, Nigeria, and assessed the relationship between dental aesthetic index (DAI) scores and periodontal status according to community periodontal index of treatment needs (CPITN) scores. One hundred forty five patients-70 (48.3%) males and 75 (51.7%) females from 6 to 45 years (mean 15.8 +/- 7.5)-were seen. World Health Organization (WHO) guidelines were followed in the examination and reporting of the periodontal status, and DAI scores were assessed based on WHO guidelines. The chi-square test was used to determine the association between the DAI and the CPITN scores. Most patients were in the 6-15 (55.9%) or 16-25 (35.9%) age groups. Based on the WHO preferred cumulative calculations of treatment need (TN), 35.2% of the patients had TN 0, 64.9% had TN 1, 24.9% had TN 2, and only 0.7% had TN 3. The relationship between DAI scores and periodontal treatment needs was not statistically significant (P >.05). Although many patients were yet to attain the WHO goal of no more than 1 sextant affected by bleeding or calculus at the age of 15, over one third had satisfactory periodontal health. 相似文献
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Dissociation of GFAP intermediate filaments in EAE: observations in the lumbar spinal cord 总被引:1,自引:0,他引:1
Acute experimental allergic encephalomyelitis (EAE) in the Lewis rat is a cell-mediated autoimmune disease of central nervous system myelin. The lesion has been characterized by breakdown of the blood-brain barrier, edema, and periventricular infiltration of macrophages and lymphocytes. At the early stage of the disease, the astrocytes show a marked increase in immunostaining for glial fibrillary acidic protein (GFAP). A corresponding increase in GFAP content, however, cannot be demonstrated. Electron microscopic examination of the early lesion shows a typical reactive astrocytic response expressed by an enlarged watery cytoplasm, particularly at the level of the processes surrounding neurons and blood vessels and in the neuropil itself. The astroglial processes contain numerous glycogen particles (aggregates and single particles). Glial filaments are also conspicuous and are arranged in small bundles or loose thin filaments adjacent to the bundles. The glial filaments that normally appear as tight bundles have expanded and appear less dense. We suggest that the increase in GFAP immunostaining of the astrocytes in the early lesion is due in part to edema, which causes dissociation of the filaments and thereby exposes more antigenic sites to the antibodies. 相似文献
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Influence of Electromagnetic Fields on Function of Automated External Defibrillators 总被引:3,自引:2,他引:1
Roman Fleischhackl MD Florian Singer MD Wolfgang Nitsche PhD MSc Eng Guenther Gamperl MSc Engineering Bernhard Roessler MD Jasmin Arrich MD Sabine Fleischhackl MD Heidrun Losert MD Fritz Sterz MD Martina Mittlboeck PhD MSc Klaus Hoerauf PhD MD 《Academic emergency medicine》2006,13(1):1-6
Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed. 相似文献
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Rapid screening of organosulfur agents for potential chemopreventive activity using the murine NA assay 总被引:1,自引:0,他引:1
The chemopreventive efficacy of 11 organosulfur compounds was assessed using the murine nuclear aberration (NA) assay in C57BL/6J mice. The sulfur compounds were introduced by stomach gavage. Benzo[a]pyrene (BP), which is a carcinogen known to a) undergo biotransformation by pathways mediated by P-450 and b) induce NA in the intestine, was used as the challenge. All animals were killed 48 hours after BP injection, and NA per crypt were scored. The results indicated that several agents were active in inhibiting BP nucleotoxicity to the colon, most notably, allyl mercaptan, benzyl mercaptan, and phenylethyl mercaptan. The NA assay was useful in effectively prescreening certain compounds for potential interactions with chemical carcinogens, thus serving as one indicator of chemopreventive activity. 相似文献
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During a 24-month period, 350 patients were prospectively studied in an effort to determine the perioperative factors in the development of infections after colon and rectal resections. All patients received standard mechanical bowel preparation; perioperative parenteral cefoxitin (group A) or preoperative oral neomycin and erythromycin, in addition to perioperative cefoxitin (Group B), were also given. Both groups were comparable with respect to age, sex, associated diseases, and primary diagnosis. Wound infections developed in nine of 169 (5%) group B patients and in 15 of 141 (11%) group A patients. Stratification by type of operative procedure revealed that the rectal resections involved the highest rate of infection in group A (22%) and in group B (11%). In patients requiring intraperitoneal colon resection, the rates of wound sepsis were similar (3% in both groups). Analysis of length of operation revealed that in operations lasting 215 minutes or more the infection rate was 12%; in those lasting less than 215 minutes the rate was 4%. Patients with rectal resection and operative times of 215 minutes or more had a wound infection rate of 19% compared to 2% (p less than 0.05) in those with shorter nonrectal operations. Group B patients with the longer rectal operations had lower infection rates (11%) than group A patients (27%), while there was no difference among those who had shorter operations. Intra-abdominal abscesses (p less than 0.01) and anastomotic dehiscence (p less than 0.05) were also significantly reduced in group B patients. Postoperative wound infection is associated with length of operation and location of colon resection and can be significantly lowered by a combination of oral and parenteral antibiotics. 相似文献
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Rolf Gronas B. Eng Peter G. Kalman MD Daryl S. Kucey MD Graham A. Wright PhD 《Journal of magnetic resonance imaging : JMRI》1997,7(4):637-643
Flow-independent angiography (FIA), an approach that isolates arterial blood using MR relaxation characteristics rather than flow effects, was evaluated for application in peripheral vascular disease (PVD). First, pilot studies were conducted in which FIA coronal projection images were obtained from controls and symptomatic patients with PVD to assess clinical utility. All control images corresponded to the expected leg arterial anatomy with little interference from deep veins (one of five) and muscle (zero of five). Superficial venous signal was less well suppressed in comparison to deep veins (four of five). Images of symptomatic patients were less consistent with difficulty suppressing muscle and deep venous signal in some cases and edema when present. We then compared T2 values for muscle (T2m, tibialis anterior), arterial blood (femoral and popliteal arteries), and venous blood (femoral, popliteal, and saphenous veins) in controls (n = 8) and symptomatic patients with intermittent claudication (n = 5) or ischemic rest pain (n = 7). Changes in T2 measurements of various tissues accounted for poorer contrast in symptomatic patients. Patients with ischemic rest pain had significantly higher T2m compared with controls (T2m = 39.3 ± 2.1 (1 standard error of the mean [SEM]) versus 30.9 ± .4, P < .01). For all measurements, other than saphenous vein, variances were greater in symptomatic patients. To realize the inherent advantages of FIA for this clinical application, additional work on suppression of signals from muscle, veins, and edema is required. One promising approach involves shifting from projection images to three-dimensional acquisitions for improved tissue suppression. 相似文献