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Introduction. The present case study is an analysis of the effect of compression socks on hemostatic activation following a marathon in a female endurance athlete found to be heterozygous for the coagulation factor V (F5 1691 G>A [Arg>Gln rs6025/560]) risk allele that predisposes one to a genetically inherited disorder of blood clotting, Factor V Leiden. Methods. Markers for coagulation and fibrinolysis were obtained 24 h prior to (PRE), immediately after (FINISH) and 24 h after (POST) completion of two marathons: the first in which the runner was not wearing compression socks, and the second in which the runner wore compression socks throughout the race. Results. Compression socks worn during a marathon appeared to lower the overall impact on hemostasis as well as clot formation in this particular athlete as evidenced by lower t-PA (–56%), TAT (–63%) and D-dimer (–30%). Conclusions. Hemostatic activation may be lower with the use of compression socks, and thus may be effective for preserving hemostasis in endurance athletes at risk.  相似文献   
3.
《Cor et vasa》2014,56(5):e420-e423
The acute mitral insufficiency is a life-threatening condition that may be caused by heavy physical strain, especially during the simultaneous occurrence of the myxomatous degeneration of the mitral valve. The mortality of the untreated illness is 75% during the first 24 h after the occurrence; the perioperative mortality is also high.The case study describes the story of a 57-year-old male, an active sportsman (long-distance runner), whose health condition was duly examined in an institute of sport medicine in Germany, and the results were reportedly always normal. Immediately after finishing a marathon run here, in Prague, he began to complain of severe dyspnea, NYHA III–IV. The physical examination revealed clearly audible strong systolic murmur with the amplitude on the heart apex with propagation into the left axilla, and the signs of pulmonary congestion were present. The transthoracic echocardiography confirmed the suspected acute mitral regurgitation, with a minor dilatation of the left atrium, and the hyperkinetic left ventricle with the preserved systolic function (EF 70%).After the confirming examination using transoesophageal echocardiography, the surgical revision of the mitral valve was indicated. This revealed myxoid degeneration of both leaflets of the mitral valve, tendinous cord rupture, and the dilatation of its annulus. A successful preservation operation was performed, together with the mitral plastic surgery, annuloplasty, and tendinous cord replacement. Having recovered from the difficulties of the post-surgery period, the patient was released to the domestic care on the 14th day after the operation.  相似文献   
4.

Background

Short-term and intermediate-term wear rates for highly cross-linked polyethylene (HCLPE) liners in total hip arthroplasty (THA) are significantly lower than published rates for traditional polyethylene liners. The aim of this study was to report the longest-to-date follow-up of a specific HCLPE liner.

Methods

A series of 35 THAs using a specific HCLPE liner were reviewed. Anteroposterior radiographs were reviewed for femoral head penetration, the presence of femoral and/or acetabular osteolysis, long-term survival, total wear, and wear rates in all patients.

Results

The average patient age at time of surgery was 70 years with an average follow-up of 10 years (118 months; range, 7.2-13.4 years). The mean wear rate in our cohort was 0.07 mm/y. Total wear was 0.71 mm over the study period. No hips showed evidence of osteolysis in any zones. Survivorship at latest follow-up was 100% with all-cause revision as an end point.

Conclusion

The wear rate of HCLPE liners continues to be lower than published wear rates for traditional polyethylene and continues to reaffirm the acceptably low wear rates using HCLPE acetabular liner in primary THA.  相似文献   
5.
Engaging in intensive aerobic exercise, specifically endurance sports, is associated with HPA axis activation indicated by elevated cortisol levels. Whether the repeated short-term elevations in cortisol levels result in higher long-term cortisol exposure of endurance athletes has been difficult to examine since traditional methods of cortisol assessments (saliva, blood, urine) reflect only relatively short time periods. Hair segment analysis provides a new method to assess cumulative cortisol secretion over prolonged time periods in a retrospective fashion. The aim of this study was to investigate cumulative cortisol secretion over several months reflecting intensive training and competitive races by examining hair cortisol levels of endurance athletes. Hair samples were obtained from 304 amateur endurance athletes (long-distance runners, triathletes, cyclists) and 70 controls. Cortisol concentrations were determined in the first to third 3-cm hair segments most proximal to the scalp. In addition, self-report measures of training volume were obtained. Endurance athletes exhibited higher cortisol levels in all three hair segments compared to controls (p<.001). Positive correlations between the cortisol concentration in the first hair segment and each indicator of training volume were found (all p<.01). These data suggest that repeated physical stress of intensive training and competitive races among endurance athletes is associated with elevated cortisol exposure over prolonged periods of time. These findings may have important implications with regard to somatic and mental health of athletes which should be investigated in future research.  相似文献   
6.
Summary Epidemiological evidence suggests that marathon runners have a higher incidence of renal stone formation than occurs in the general population. Since crystalluria and stone disease are thought to be related, we subjected urine samples from a group of marathon runners to particle counting and sizing in a Coulter Counter equipped with a population accessory unit. The volume-size distribution curves so obtained were bimodal with one peak occurring in the 2–5 m diameter range and a second in the 15–32 m diameter range—a pattern that is remarkably similar to the distributions reported for recurrent idiopathic stone formers and distinctly different to those recorded for control subjects. Analyses by scanning electron microscopy and X-ray powder diffraction revealed other features which are regarded as typical of stone formers' crystalluria. These physicochemical data indicate that marathon runners may be at increased risk of urinary stone formation.  相似文献   
7.
Summary The occurrence of possible prolonged alterations in plasma levels of cortisol, epinephrine, norepinephrine, selected energy metabolites, and water and electrolyte balance was assessed in six highly trained male marathon runners by measuring blood biochemical constituents on the 10th day before and for the three days following the running of a marathon. Post-race changes in hemoglobin, hematocrit, and protein levels indicated that a hemodilution had occurred, possibly as a result of elevated sodium levels. Epinephrine remained elevated until the second day. Cortisol was depressed on the first and third post-race days while variable levels were observed on the second day. No prolonged alterations were noted in norepinephrine, FFA, glycerol, triglycerides, glucose, lactate, and pyruvate.This work was supported in part by the Air Force Office of Scientific Research, Air Force Systems Command, Grant AFOSR 73-2455  相似文献   
8.
Serial total creatine kinase (CK) and CK MB activities were determined in the serum of seven runners following a marathon race and compared to enzyme activities in the sera from five patients following acute myocardial infarction (AMI). In the runner's sera, total CK and CK MB activities were significantly elevated at 1, 24, 48 and 72 hours post marathon race when compared to the 1 hour pre-marathon samples (p < 0.01). Serum CK MB activities peaked at 24 hours in both groups of subjects. The MB activities 24 hours following the marathon were substantially higher (91 ± 30 U/l; mean ± SD) than the MB activities 24 hours following AMI (46 ± 38 U/l). However, the percentages of CK MB 24 hours following the marathon and AMI were almost identical (7.0 ± 2.4% and 7.2 ± 2.3%, respectively). Furthermore, CK and CK MB clearances were significantly prolonged (p < 0.02 and p < 0.001, respectively) following the marathon race (T 12 CK, 49 hours; T 12 CK MB, 29 hours) as compared to following AMI (T 12 CK, 27 hours; T 12 CK MB, 12 hours). These results suggest release of CK MB from the skeletal muscle of marathon runners. Therefore, we recommend that elevation of CK MB in the range indicative of myocardial damage be interpreted with caution in long-distance runners.  相似文献   
9.
Background To assess left ventricular volumes and mass by cardiac magnetic resonance imaging in relation to conventional cardiovascular risk factors and coronary atherosclerotic plaque burden in master marathon runners aged ≥50 years. Methods Cardiac MRI was performed in 105 clinically healthy male marathon runners (mean age 57.3 ± 5.7 years, range 50–71 years) on a 1.5 T MR system (Avanto, Siemens, Germany). Cine steady state free precession images in standard long and short axes views were acquired to assess left ventricular volumes and mass. Cardiovascular risk factors (blood pressure, HDL/LDL cholesterol, smoking, body mass index) were assessed and coronary artery calcification (CAC) was quantified by electron beam computed tomography. Results Left ventricular muscle mass (mean LVMM = 140 ± 27 g; 73 ± 13 g/m2) increased with increasing left ventricular end-diastolic volume (mean LVEDV = 137 ± 32 ml; 72 ± 15ml/m2) (r = 0.41, < 0.0001) and with systolic (r = 0.33, P = 0.005) and diastolic (r = 0.28, P = 0.005) blood pressures. Left ventricular EDV increased up to the age of 55 years, but decreased thereafter. Runners with LVMM ≥150 g had significantly higher CAC scores than runners with LVMM <150 g (median CAC score 110 vs. 25, P = 0.04). Conclusions Increases in LVMM and LVEDV may not only represent a response to exercise but are dependent on age and blood pressure, also. In addition, a left ventricular hypertrophy without an increase in volume may be an indicator for early subclinical cardiac alterations in response to risk factor exposure.  相似文献   
10.
Chemokines are elevated in plasma after strenuous exercise in humans   总被引:3,自引:0,他引:3  
During the last few years much attention has been paid to the chemokines. Chemokine receptors are necessary to render a target permissive for infection by the human immunodeficiency virus (HIV) and high concentrations of chemokines have been shown to protect against the progression of HIV disease towards death. In the present study, we investigated the capability of strenuous exercise to induce elevated plasma concentrations of the chemokines interleukin (IL)-8, macrophage inflammatory protein (MIP)-1α and MIP-1β. Eight male athletes completed the Copenhagen Marathon 1997. Blood was sampled before, immediately after the run and every 30 min during a 4 h recovery period. Plasma chemokine concentrations were measured using enzyme-linked immunosorbent assays. The IL-8, MIP-1α and MIP-1β concentrations all peaked 0.5 h after the run when they were 6.7-fold, 3.5-fold and 4.1-fold increased, respectively. The elevated concentrations of chemokines in plasma after exercise could have implications for HIV-infected individuals; a possibility that needs further investigation. Accepted: 21 September 2000  相似文献   
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