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11.
This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups.  相似文献   
12.
S B Sherriff  R C Smart    I Taylor 《Gut》1977,18(12):1027-1031
During the course of a clinical trial to assess the value of adjuvant liver perfusion of 5-fluorouracil after surgery for colorectal cancer, liver blood flow was measured in 14 patients. Access to the portal circulation was achieved by dilatation and cannulation of the obliterated umbilical vein. The clearance from the liver of a bolus of 133Xe was monitored using a gamma-ray camera so that blood flow from different areas of the liver could be calculated. The clearance curve of 133Xe was a double exponential of which the initial fast component accounted for a consistently high proportion of the total clearance. The perfusion studies have shown wide differences in blood flow to the various areas of the liver in the same patient, in addition to a wide variation in perfusion rate between the 14 patients. This technique of quantitative estimations of liver blood flow to different areas of the liver may have importance in planning operative procedures and understanding the haemodynamic mechanisms involved in liver disease.  相似文献   
13.
The purpose of this study was to compare the effectiveness of a plasma arc lamp with a conventional tungsten quartz halogen lamp in orthodontic bonding. Twenty consecutive patients had their brackets bonded either with Transbond XT (n = 10) or Fuji Ortho LC (n = 10). In total, 352 teeth were bonded, 176 in each group. Using a randomized cross-mouth control study design, where diagonally opposite quadrants were assigned a particular treatment, the bonds were then either cured with the control light, namely a halogen lamp, or a plasma arc lamp. The halogen light was used for 20 seconds per tooth and the plasma arc lamp for 3 seconds per tooth. The measurement parameter used was bond failure and the patients were monitored for a period of 6 months following initial bond placement.In the Transbond XT group, the proportion of bond failures was 3.41 per cent for both the halogen and the plasma arc lamp. For the Fuji Ortho LC group, the proportions were 11.4 and 10.2 per cent, respectively. No difference was observed with respect to in-service bond failure proportions between bonds cured with the plasma arc or the conventional halogen lamp, irrespective of the bonding agent. Use of the plasma arc lamp could therefore lead to considerable savings in clinical time. However, this must be weighed against the increased purchase price of the plasma arc lamp.  相似文献   
14.
AIM: The aim of this in-vitro study was to measure interfacial forces acting between root canal dentine and ultrasonic files during endosonic instrumentation. METHODOLOGY: Single-rooted teeth were mounted on a cantilevered aluminium beam to which two pairs of single element strain gauges were joined in a half-bridge configuration mounted at right angles to each other. The strain gauges were connected to an analogue-to-digital converter fitted in a microcomputer via a conditioning amplifier. This enabled strains to be recorded as a function of interfacial forces over a period of time. Twenty operators instrumented root canals using sizes 15, 20 and 25 ultrasonically energized K-type files. The lateral forces generated were calculated. RESULTS: The mean interfacial forces used varied widely between operators and files, ranging from 18 g to 149 g, but there was a consistency in the relative magnitude for each operator. The average force used by the operators increased with file size; the differences between file sizes were significant (P < 0.05). CONCLUSIONS: The range of forces measured is broader than previously reported and may have a bearing on possible uncontrolled dentine removal, even during ultrasonically activated irrigation.  相似文献   
15.
Sherriff JL 《The Medical journal of Australia》2003,178(6):303; author reply 303-303; author reply 304
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16.
AIMS—To investigate the relation between haemoglobin in children followed longitudinally from 8 to 18 months, and developmental outcome at 18months.
METHODS—The Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) is a longitudinal survey of a geographically defined population of children born in 1991-92. In a randomly selected subsample, blood samples were assayed for Hb at 8, 12, and 18 months; a developmental assessment was carried out at 18 months on 1141 children using the Griffiths Scales of Mental Development.
RESULTS—There was a strong quadratic association between Hb at 8 months and performance on the locomotor subscale at 18 months. Average scores increased with increasing Hb up to 95 g/l; there was little additional developmental benefit in Hb levels beyond 95 g/l. Infants with Hb <95 g/l at 8 months of age scored on average 6 points lower on the locomotor subscale than infants with Hb ⩾ 95 g/l; infants with Hb <90 g/l at 8 months scored 12 points lower on the locomotor subscale than children with Hb ⩾ 90 g/l.
CONCLUSIONS—Low Hb concentrations (⩽ 95 g/l) in 8 month old children are associated with impaired motor development at 18 months. This cut off point corresponds to the 5th centile of Hb at 8 months. The results indicate that if there is an adverse effect of low Hb on developmental outcome, screening may be more effective at 8 months or earlier, rather than after this age. We propose to examine the importance of infant anaemia in relation to more accurate and detailed long term outcomes as the children get older.

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17.
The aim of this study was to investigate the possible relationship between interfacial forces, duration of instrumentation and effectiveness of root canal shaping by filing. All factors were standardised except the manner of manipulation of the files and the dependent variables (interfacial force and duration of filing). The outcome measured was the final prepared canal shape. The study tested the hypothesis that if interfacial forces and duration of filing had predictive value for effective canal shaping, a relationship between them should be apparent. If it was not, it could be inferred that the remaining uncontrollable variable, "manner of file manipulation" had a dominating influence. 18 operators used a standard filing technique to instrument a root canal each in single rooted teeth matched for anatomy. The teeth were mounted in a custom-made transducer designed to measure laterally applied interfacial forces between file and dentine. The length of time taken with each instrument in the series was measured giving a total duration of instrumentation. The final canal shape measured by standardised "before" and "after" radiographic images of the roots was judged against an "ideal" canal shape calculated from the size of instruments used and based on the preliminary canal shape. Although some trends were revealed, no obvious relationship was demonstrated between interfacial force, duration of filing and final canal shape. Operators clearly used a range of interfacial forces characteristic for each individual and for the different file sizes. Both light and heavy forces could produce a satisfactory canal shape. Use of light or heavy forces did not obviously affect speed of preparation. Tactile discrimination was not dependent on use of light or heavy forces. It was inferred that the "manner of file manipulation" remained undefined and was probably the dominant factor influencing outcome of canal shaping.  相似文献   
18.
OBJECTIVE: To study the serum and peritoneal fluid cytokine profiles in infertile women with minimal/mild active endometriosis. METHODS: Fifty-seven consecutive infertile women undergoing laparoscopy for unexplained infertility had peritoneal fluid and serum samples obtained at the time of laparoscopy. The levels of interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-1 beta (IL-1 beta), vascular endothelial growth factor (VEGF), tumor necrosis factor-alpha (TNF-alpha), monocyte chemotatic protein-1 (MCP-1), RANTES, platelet derived growth factor (PDGF), soluble Fas (sFas), and soluble Fas Ligand (sFasL) in peritoneal fluid and serum were measured to compare the concentration in both biological fluids, in women who have minimal/mild red endometriosis using women with no endometriosis as controls. RESULTS: Peritoneal fluid levels of MCP-1, IL-8 and IL-6 were significantly higher in the endometriosis group (P < 0.012, P = 0.003, and P = 0.015, respectively). There was no significant difference in the peritoneal fluid levels of IL-1 beta, TNF-alpha, RANTES, VEGF, PDGF, sFas and sFasL in the two groups. Although serum levels of IL-8 were higher in women with endometriosis, the difference was not significant (P = 0.07). Serum levels of PDGF, IL-6, RANTES, IL-1 beta, TNF-alpha, and sFas, were not significantly different in the two groups. CONCLUSION: The elevated levels of MCP-1, IL-6, and IL-8 in peritoneal fluid but not serum may indicate the importance of local macrophage activating factors in the pathogenesis of endometriosis.  相似文献   
19.
Journal of Community Health - Little is known about Community Health Workers (CHWs) who work in non-clinical settings to provide sexual health support around HIV, viral hepatitis, and other...  相似文献   
20.
OBJECTIVE: To establish the relation between socioeconomic status and the age-sex specific prevalence of type 1 and type 2 diabetes mellitus. The hypothesis was that prevalence of type 2 diabetes would be inversely related to socioeconomic status but there would be no association with the prevalence of type 1 diabetes and socioeconomic status. SETTING: Middlesbrough and East Cleveland, United Kingdom, district population 287,157. PATIENTS: 4313 persons with diabetes identified from primary care and hospital records. RESULTS: The overall age adjusted prevalence was 15.60 per 1000 population. There was a significant trend between the prevalence of type 2 diabetes and quintile of deprivation score in men and women (chi 2 for linear trend, p < 0.001). In men the prevalence in the least deprived quintile was 13.4 per 1000 (95% confidence intervals (95% CI) 11.44, 15.36) compared with 17.22 per 1000 (95% CI 15.51, 18.92) in the most deprived. For women the prevalence was 10.84 per 1000 (95% CI 9.00, 12.69) compared with 15.48 per 1000 (95% CI 13.84, 17.11) in the most deprived. The increased prevalence of diabetes in the most deprived areas was accounted for by increased prevalence of type 2 diabetes in the age band 40-69 years. There was no association between the prevalence of type 1 diabetes and socioeconomic status. CONCLUSION: These data confirm an inverse association between socioeconomic status and the prevalence of type 2 diabetes in the middle years of life. This finding suggests that exposure to factors that are implicated in the causation of diabetes is more common in deprived areas.  相似文献   
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