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61.
This study investigated the effects of oral supplementation with ubiquinone-10 (Q10) (n = 9) compared with a placebo (n = 9) on aerobic and anaerobic physical performance over 22 days of supplementation. The supplementation period included 5 days of high intensity anaerobic training between days 11 and 14. The results demonstrated, that on an anaerobic (10 × 10 s) cycling test, the?placebo group showed a significantly greater improvement than the Q10-group after a supplementation and training period (P < 0.001). Further, the Q10 group had a significantly lower increase in total work performed during the seven training sessions (15 × 10 s) compared with the placebo group (P < 0.001). There was a significant increase in maximal blood lactate accumulation during cycling in the both groups, when compared with levels before the training and recovery period. There was no significant difference between the groups, either in VO 2max determined during running, or in submaximal and peak VO 2, Rate of Perceived Exertion, respiratory quotient, blood lactate concentration or heart rate determined during submaximal and maximal cycling. Although insignificant?(P = 0.1–0.3), there was evidence of higher submaximal VO 2 (55–80% of VO 2peak) during cycling in the Q10-group compared with the placebo group after training and recovery. It is concluded that with high intensity anaerobic training, there was a significantly greater increase in anaerobic performance in the placebo group compared with the Q10 group. The results suggest less increase in physical performance with Q10 supplement and high intensity anaerobic training, compared with placebo.  相似文献   
62.

Background

Intraoperative Radiotherapy (IORT) is a method by which a critical radiation dose is delivered to the tumour bed immediately after surgical excision. It is being investigated whether a single high dose of radiation will impart the same clinical benefit as a standard course of external beam therapy. Our centre has four Photon Radiosurgery Systems (PRS) currently used to irradiate breast and neurological sites.

Materials and methods

The PRS comprises an x-ray generator, control console, quality assurance tools and a mobile gantry. We investigated the dosimetric characteristics of each source and its performance stability over a period of time. We investigated half value layer, output diminution factor, internal radiation monitor (IRM) reproducibility and depth-doses in water. The half value layer was determined in air by the broad beam method, using high purity aluminium attenuators. To quantify beam hardening at clinical depths, solid water attenuators of 5 and 10 mm were placed between the x-ray probe and attenuators. The ion chamber current was monitored over 30 minutes to deduce an output diminution factor. IRM reproducibility was investigated under various exposures. Depth-dose curves in water were obtained at distances up to 35 mm from the probe.

Results

The mean energies for the beam attenuated by 5 and 10 mm of solid water were derived from ICRU Report 17 and found to be 18 and 24 keV. The average output level over a period of 30 minutes was found to be 99.12%. The average difference between the preset IRM limit and the total IRM count was less than 0.5%. For three x-ray sources, the average difference between the calculated and actual treatment times was found to be 0.62% (n = 30). The beam attenuation in water varied by approximately 1/r3.

Conclusion

The x-ray sources are stable over time. Most measurements were found to lie within the manufacturer's tolerances and an intercomparison of these checks suggests that the four x-ray sources have similar performance characteristics.  相似文献   
63.

Background

To describe long-term changes in time of quality of life (QOL) and the relation with parotid salivary output in patients with head-and-neck cancer treated with radiotherapy.

Methods

Forty-four patients completed the EORTC-QLQ-C30(+3) and the EORTC-QLQ-H&N35 questionnaires before treatment, 6 weeks, 6 months, 12 months, and at least 3.5 years after treatment. At the same time points, stimulated bilateral parotid flow rates were measured.

Results

There was a deterioration of most QOL items after radiotherapy compared with baseline, with gradual improvement during 5 years follow-up. The specific xerostomia-related items showed improvement in time, but did not return to baseline. Global QOL did not alter significantly in time, although 41% of patients complained of moderate or severe xerostomia at 5 years follow-up. Five years after radiotherapy the mean cumulated parotid flow ratio returned to baseline but 20% of patients had a flow ratio <25%. The change in time of xerostomia was significantly related with the change in flow ratio (p = 0.01).

Conclusion

Most of the xerostomia-related QOL scores improved in time after radiotherapy without altering the global QOL, which remained high. The recovery of the dry mouth feeling was significantly correlated with the recovery in parotid flow ratio.  相似文献   
64.
ANDERS ROMELSJÖ  M.D.  Ph.D.    LENA ANDERSSON  M.D.    HAKAN BARRNER  M.D.    STEFAN BORG  M.D.  Ph.D.    CLAES GRANSTRAND  M.D.    OLLE HULTMAN  M.D.    ANNIKA HÄSSLER  M.D.    ANNA KäLLQUIST  M.D.    PETER MAGNUSSON  M.D.    ROLAND MORGELL  M.D.    KJELL NYMAN  M.D.    ERS OLOFSSON  M.D.    EVA OLSSON  M.D.    ERS RHEDIN  M.D  OLLE WIKBLAD  M.D 《Addiction (Abingdon, England)》1989,84(11):1319-1327
The subjects were recruited from participants in a health examination of random samples of the adult population in Stockholm county. Those aged 18–64years who admitted a high alcohol consumption (>40 g 100% ethanol/day) among men and <30 g among women) or had an elevated value of serum-gammaglutamyltransferase (GOT) (cut-off point 1.0 microkatal/l for men and 0.6 microkatal/l for women) or had certain other indications of a high alcohol consumption were included. More severe cases, and those with an elevated GOT due to reasons other than alcohol, were excluded. The remaining subjects, 70 men and 13 women, were allocated at random to either an intervention or a comparison group. An elevated GGT was the main inclusion criteria. The subjects in the comparison group were advised by the general practitioner to cut their alcohol consumption, while those in the intervention group made further visits to their general practitioner, who gave general support and used an elevated GGT as an indication of the recent level of alcohol consumption at consecutive visits. There were three visits on average, so we are comparing a group receiving advice with a group receiving further minimal intervention. At the one-year follow-up there were greater, however not significant, reductions in GGT-level, in self-reported alcohol consumption and in a ‘problem index’ in the minimal intervention group than in the comparison group.  相似文献   
65.
The European Respiratory Society Task Force on primary ciliary dyskinesia (PCD) in children recently published recommendations for diagnosis and management. This paper compares these recommendations with current clinical practice in Europe. Questionnaires were returned by 194 paediatric respiratory centres caring for PCD patients in 26 countries. In most countries, PCD care was not centralised, with a median (interquartile range) of 4 (2-9) patients treated per centre. Overall, 90% of centres had access to nasal or bronchial mucosal biopsy. Samples were analysed by electron microscopy (77%) and ciliary function tests (57%). Nasal nitric oxide was used for screening in 46% of centres and saccharine tests in 36%. Treatment approaches varied widely, both within and between countries. European region, size of centre and the country's general government expenditure on health partly defined availability of advanced diagnostic tests and choice of treatments. In conclusion, we found substantial heterogeneity in management of PCD within and between countries, and poor concordance with current recommendations. This demonstrates how essential it is to standardise management and decrease inequality between countries. Our results also demonstrate the urgent need for research: to simplify PCD diagnosis, to understand the natural history and to test the effectiveness of interventions.  相似文献   
66.
67.
Abstract— The aim was to evaluate chemically modified starches (CMS) from a cariologic point of view as alternatives to gum arabic in sugar-free lozenges. Two commercial CMS, Purity Gum 40 and Capsul, were selected due to their comparatively low availability to alpha-amylase in vitro. Both gelatinized CMS suspensions and lozenges were tested in vivo by measuring plaque pH. The results showed that suspensions of Purity Gum 40 or Capsul were less available to alpha-amylase in vitro than the soluble starch reference. However, the initial phase of amylolysis was comparatively rapid also with CMS. In spite of the slower rate of hydrolysis, suspensions of the two CMS reduced pH of dental plaque in vivo to the same extent as soluble starch, but somewhat less compared with glucose. Lozenges with Purity Gum 40 also lowered plaque pH, although less than when administered as a precooked suspension. The most prominent pH drop was found with a lozenge containing Purity Gum 40-sucrosc-glucose, while tablets with gum arabic-maltitol and pectin-gelatine-Lycasin somewhat increased the pH values. To conclude, it is not recommended to exchange gum arabic for CMS in sugar-free lozenges, since the cariogenic properties of the products are negatively affected.  相似文献   
68.
The serum levels of zinc and retinol-binding protein (RBP) have been determined in 173 patients with acne and compared with those of a control group. The RBP is a specific transport protein and its level in plasma reflects the amount of vitamin A available to the tissues. Patients with severe acne were found to have lower levels of RBP than either patients with mild acne or healthy subjects of the same age. In the case of males with severe acne, the mean serum zinc level was significantly lower than that of the control group. No such difference was observed for girls. The observed condition of low levels of zinc and vitamin A in the serum of patients with severe acne may provide a rationale for the clinically good effect of oral zinc treatment.  相似文献   
69.
We analysed the production of nitric oxide (NO) intermediates by cells from BALB/c mice infected with either virulent (Tulahuén or RA) or avirulent (CA-1) strains of Trypanosoma cruzi. Peritoneal or spleen cells from mice infected with T. cruzi released NO when incubated without further stimuli. Cells from mice during the acute stage of infection accumulated higher levels of inducible NO synthase mRNA and produced both, before and after lypopolysaccharide stimulation, higher amounts of NO than cells from mice chronically infected with T. cruzi. NO synthesis showed similar kinetics in connection with all three strains ofT. cruzi, but cells from mice inbred with the Tulahuén or RA strains released higher levels of IFN-γ, an activator of the NO pathways, than cells from mice infected with the CA-1 strain. In vivo administration of L-Ng-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of NO synthase, increased the susceptibility of mice to T. cruzi. We conclude that infection with T. cruzi induces NO production, and suggest that NO plays a role in the resistance against the parasite.  相似文献   
70.
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