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1.
A comparative study of the physical performance capacity of 32 Burmese women aged 19-24 years of the rural and urban area was conducted. Difference in physique was found between the two groups. Maximal oxygen uptake of the rural group was 39.21 ml/kg/min and that of the urban group was 32.32 ml/kg/min, the difference being significant at 0.1% level. Maximal oxygen pulse and maximal work load were significant only at 2% and 5% levels respectively. Though maximal ventilation in the rural group had a higher mean value it was not significant. These showed a higher cardiorespiratory fitness in the rural group, which was attributable to their high work intensity of 55.13% of the maximal aerobic power. However, a positive training effect of habitual physical activity on muscle strength could not be observed in this study.  相似文献   
2.
Vasopressin for cardiac arrest: a systematic review and meta-analysis   总被引:5,自引:0,他引:5  
BACKGROUND: The current guidelines for cardiopulmonary resuscitation recommend vasopressin as an alternative to epinephrine for the treatment of adult shock-refractory ventricular fibrillation. The objective of this study was to determine the effectiveness of vasopressin in the treatment of cardiac arrest. METHODS: We performed a systematic review and meta-analysis of 1519 patients with cardiac arrest from 5 randomized controlled trials that compared vasopressin and epinephrine. Two reviewers conducted a systematic search of electronic databases, complemented by hand searches, to identify randomized trials. Reviewers evaluated the quality of the trials, extracted data, and derived pooled estimates using a random-effects model. RESULTS: There were no statistically significant differences between the vasopressin and epinephrine groups in failure of return of spontaneous circulation (risk ratio [RR], 0.81; 95% confidence interval [CI], 0.58-1.12), death before hospital admission (RR, 0.72; 95% CI, 0.38-1.39), death within 24 hours (RR, 0.74; 95% CI, 0.38-1.43), death before hospital discharge (RR, 0.96; 95% CI, 0.87-1.05), or combination of number of deaths and neurologically impaired survivors (RR, 1.00; 95% CI, 0.94-1.07). Subgroup analysis based on initial cardiac rhythm showed no statistically significant difference in the rate of death before hospital discharge between the vasopressin and epinephrine groups in any of the 3 subgroups: ventricular fibrillation or ventricular tachycardia (RR, 0.97; 95% CI, 0.79-1.19), pulseless electrical activity (RR, 1.02; 95% CI, 0.95-1.10), or asystole (RR, 0.97; 95% CI, 0.94-1.00). CONCLUSIONS: There is no clear advantage of vasopressin over epinephrine in the treatment of cardiac arrest. Guidelines for Advanced Cardiac Life Support should not recommend vasopressin in resuscitation protocols until more solid human data on its superiority are available.  相似文献   
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BACKGROUND: Elevated mean corpuscular volume (MCV) is a traditional biological marker for alcohol abuse and alcoholism, but the underlying mechanism is unclear. Three recent epidemiologic studies consistently showed that MCV was elevated by alcohol drinking more markedly among individuals with genetically inactive aldehyde dehydrogenase-2 (ALDH2) (encoded by ALDH2*2 mutant allele) than those with active ALDH2 (encoded by ALDH2*1/2*1 genotype), suggesting that the elevated MCV was etiologically linked to acetaldehyde exposure. The purpose of the present study was to clarify further this relationship by examining the status of folate and vitamin B12. METHODS: The study participants were 159 men who were aged 40 to 69 years and randomly selected from a Japanese rural population. The genetic polymorphism of ALDH2 was determined by PCR-restriction fragment length polymorphism method; data on alcohol drinking and other lifestyles were collected using a structured questionnaire; serum concentrations of folate and vitamin B12 were measured using the protein competitive reaction method, and blood cell counts were measured by routine methods. A multiple linear regression model was used to analyze the data. RESULTS:: The relationship between alcohol drinking and serum folate concentration was significantly different between ALDH2 genotypes, indicating that the reduction of serum folate by alcohol drinking was more marked in men with ALDH2*1/2*2 than those with ALDH2*1/2*1. The relationship between alcohol drinking and elevated MCV was significantly stronger in men with ALDH2*1/2*2 than those with ALDH2*1/2*1 even after adjustment for serum folate and vitamin B12 concentrations. CONCLUSIONS: These findings indicate that acetaldehyde plays a significant role in the development of decreased serum folate concentration and elevated MCV by alcohol drinking.  相似文献   
5.
Mild hyperhomocysteinemia is one of the known strong risk factors for atherosclerotic diseases, and therefore it is important to clarify factors that could determine plasma total homocysteine (tHcy) level. A cross-sectional study with a random sample of 455 Japanese rural residents aged 40-69 years was conducted in 2000 to investigate the associations of plasma tHcy concentration with 5,10-methylenetetrahydrofolate reductase (MTHFR) gene and selected life-style related factors. The frequency of the mutant allele, Valine (V) allele, was 0.40 and the prevalence of VV genotype was 14.3%. Plasma tHcy concentration in VV was significantly higher than those in two other genotypes. There were significant inverse associations of plasma tHcy with serum folate and serum vitamin B12 (P<0.001 for trend, respectively); both being stronger in VV than in other genotypes. The number of cigarettes smoked per day was positively associated with plasma tHcy concentration. A multivariate regression analysis revealed that serum folate, serum vitamin B12, and MTHFR genotype were independently associated with plasma tHcy. The inter-individual variance of plasma tHcy was more explained by serum folate and vitamin B12 than by MTHFR genotype. Higher intakes of folate, vitamin B12, and non-smoking may be important to prevent mild hyperhomocysteinemia and the eventual atherosclerotic diseases in this Japanese rural population.  相似文献   
6.
BACKGROUND: The purpose of this study was to generate right ventricular (RV) pressure-volume loops (PVLs) from time-activity curves obtained by first-pass radionuclide angiography (RNA) and RV pressures obtained by right heart catheterization. METHODS AND RESULTS: Short-lived tantalum 178 was used to obtain first-pass RNA at baseline (n = 31), after nitroglycerin (n = 5), or after the conclusion of cardiac catheterization (n = 13). From the radionuclide-derived RV ejection fraction and thermodilution stroke volume, the RV end-diastolic volume and end-systolic volume were measured. Special proprietary software was developed and used to integrate the pressure and the RNA data. The mean heart rate was 80 +/- 17 beats/min; RV ejection fraction, 39% +/- 12%; RV end-diastolic volume, 217 +/- 79 mL; RV end-systolic volume, 142 +/- 74 mL; and RV end-diastolic pressure, 10 +/- 7 mm Hg. The RV PVLs were of high quality and reproducible. CONCLUSIONS: This study provides proof of concept of the feasibility of generating RV PVL; the short half-life (10 minutes) and low energy (59 keV) of Ta-178 allow the generation of multiple loops at low radiation exposure. Such studies could be performed at the bedside and provide a wealth of information that may have clinical and research merits.  相似文献   
7.
BACKGROUND: Prior studies with first-pass radionuclide angiography (RNA) during treadmill exercise used a single-crystal (Anger) or multicrystal gamma camera and technetium 99m tracers. Motion correction, when done, used point sources, which limited correction to only plane movement. METHODS AND RESULTS: We examined the performance of a multiwire gamma camera (MWGC), generator-produced tantalum 178, and a novel method of motion correction during treadmill exercise testing. We studied 100 patients in whom rest and stress gated tomographic myocardial perfusion images were obtained. Eight patients were excluded because of incomplete data. There were 53 men and 39 women aged 52 +/- 12 years. The resting left ventricular (LV) ejection fraction (EF) was 61% +/- 12% by gated single photon emission computed tomography. Stress myocardial perfusion was normal in 83 patients and abnormal in 9 patients. The resting RNA EF in the upright position was 57% +/- 12% (r = 0.52, P = .0001 vs gated EF). At peak exercise, the EF by MWGC was 60% +/- 26% if uncorrected and 69% +/- 13% after motion correction. Among the 80 patients with normal perfusion and normal resting EF by gated single photon emission computed tomography, a normal response to exercise was seen in 52 (63%) without motion correction and 74 (89%) with motion correction (P < .05). CONCLUSION: Assessment of LV function is feasible with MWGC. The motion-corrected images significantly improved the results.  相似文献   
8.
Gallic acid and its alkylesters, polyphenolic compounds with antioxidative activity, acted as a prooxidant causing a copper-dependent DNA damage. Treatment of DNA from plasmid pBR322 and calf thymus with gallic acid plus copper ion caused strand scission and the formation of 8-hydroxy-2′-deoxyguanosine in DNA. Addition of catalase protected DNA from the gallic acid/copper-dependent strand breaks and the formation of 8-hydroxy-2′-deoxyguanosine, indicating that hydroxyl radical may participate in the DNA damage. Ethyl-, propyl- and butylgallates showed only a little DNA damage. Octyl- and laurylgallates caused negligible damage of DNA. DNA strand breaks and formation of 8-hydroxy-2′-deoxyguanosine were closely related to the reduction of copper by gallate compounds. These results imply that cuprous ion reduced by gallate derivatives may play a key role in the oxidative cleavage of DNA and the formation of base adduct. The cytotoxic effect of gallate compounds can be explained by their prooxidant action dependent on the reducing activity.  相似文献   
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The response to booster vaccination at 15-18 months of age and the presence of immune memory in 10-month old children, primed with a new combined diphtheria-tetanus-hepatitis B-whole cell pertussis vaccine extemporaneously mixed with Haemophilus influenzae type b-tetanus toxoid conjugate (DTPw-HBV/Hib) from new antigen sources and containing 2.5 microg polyribosyl-ribitol-phosphate (PRP) was assessed. Primary vaccination with the new DTPw-HBV/Hib vaccine was immunogenic and of comparable tolerability to commercially available Tritanrix HepB/Hiberix. Children were boosted with DTPw-HBV, DTPw-HBV/Hib or separate DTPw-HBV+Hiberix. Immune memory was assessed through administration of 10 microg PRP polysaccharide. Anti-PRP antibody GMCs increased substantially after the challenge in DTPw-HBV/Hib-primed subjects indicating the presence of immune memory. One month after the booster dose, 100% of subjects had seroprotective antibody concentrations against PRP, diphtheria and tetanus, >95% were seroprotected against hepatitis B, > or =94.0% had a pertussis booster response. Substantial increases in antibody GMCs against all antigens were observed. Swelling >20 mm was the most common Grade 3 solicited symptom reported (up to 26.0% of subjects). Fever >39.5 degrees C was uncommon (>2.5%). Eleven large swelling reactions were reported; none involved an adjacent joint. One serious adverse event occurred that was considered unrelated to vaccination. This new DTPw-HBV/Hib vaccine with new vaccine components and 2.5 microg PRP induced effective priming against Hib evidenced by a vigorous anamnestic response on exposure to PRP polysaccharide. The booster dose was immunogenic and the safety profile was acceptable. Combined DTPw-HBV and DTPw-HBV/Hib vaccines using new vaccine antigen sources will promote continued supply of combined DTPw-based vaccines to global mass vaccination campaigns.  相似文献   
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