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51.
52.
YP Zverev J Chisi 《Malawi medical journal : the journal of Medical Association of Malawi》2004,16(1):14-16
Handedness is the most important behavioural asymmetry due to its intimate association with the specialisation of the brain for language. It exists in 3 forms, namely right, left and mixed. Left-handers constitute the biggest minority group in the world and in many aspects they are in a disadvantaged position compared to right-handers. Numerous studies demonstrated association between left-handedness and different health problems ranging from learning disorders to breast cancer and decreased longevity. This paper reviews the relevant literature on the genesis of handedness and connection between handedness and health. Deviations from the “normal” pattern of braininess observed in some left-handers might contribute to developmental, cognitive and some mental disorders. However increased incidence of some of pathological conditions among sinistrals could hardly be explained by the “abnormal” pattern of braininess or by the action of a gene or genes responsible for handedness determination. Review of literature suggests that many of health problems of left-handers develop due to environmental, developmental and other mechanisms related to genesis of handedness. 相似文献
53.
Clinical characteristics of patients with exercise-induced ST-segment elevation without prior myocardial infarction. 总被引:1,自引:0,他引:1
Ming-Jui Hung Ming-Yow Hung Chi-Wen Cheng Ning-I Yang Wen-Jin Cherng 《Circulation journal》2006,70(3):254-261
BACKGROUND: Exercise-induced ST-segment elevation is a relatively uncommon problem and occurs more frequently in patients who have had a myocardial infarction. Data is limited on the characteristics of Taiwanese patients without prior myocardial infarction who develop exercise-induced ST-segment elevation. METHODS AND RESULTS: Exercise-induced ST-segment elevation developed in 9 of 6,147 consecutive patients without myocardial infarction who underwent treadmill exercise testing at out institution over a 4-year period. The clinical and angiographic characteristics of these patients were studied. Angiographically normal coronary arteries with coronary vasospasm were found in 5 patients, hemodynamically significant coronary stenosis was found in 3 patients, and coexisting spasm in angiographically normal coronary arteries combined with hemodynamically significant coronary stenosis in the different vessel was found in 1 patient. During a median follow-up of 71 months, 2 patients with coronary vasospasm developed recurrent angina after self-discontinuation of calcium antagonists and 2 patients (1 with coronary vasospasm and 1 with hemodynamically significant coronary stenosis) died of cardiac causes before arrival at the emergency department. CONCLUSION: Coronary vasospasm was a more common underlying pathology of exercise-induced ST-segment elevation in this Taiwanese cohort. Coronary angiography +/- intracoronary ergonovine provocation testing is necessary in these patients to identify the underlying pathology and appropriate treatment. 相似文献
54.
Jong-Kai Hsiao Ming-Fong Tai Hung-Hao Chu Shin-Tai Chen Hung Li Dar-Ming Lai Sung-Tsang Hsieh Jaw-Lin Wang Hon-Man Liu 《Magnetic resonance in medicine》2007,58(4):717-724
The purpose of this work was to evaluate the efficacy of labeling human mesenchymal stem cells (hMSCs) by ionic superparamagnetic iron oxide (SPIO) without a transfection agent and verifying its capability to be detected with clinical 1.5 T magnetic resonance (MR) at the single-cell level. Human hMSCs were incubated for 24 h with an ionic SPIO, Ferucarbotran. The labeling efficiency of hMSCs was determined by iron content measurement spectrophotometrically, and the influence of labeling on cell behavior was ascertained by examination of cell viability using the trypan blue exclusion method, cell proliferation analysis using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, mitochondrial membrane potential (MMP) change, differentiation capacity, and reactive oxygen species (ROS) production measured by dichlorofluorescein diacetate (DCFDA) fluorescent probe. Labeled hMSCs were scanned under 1.5 T MRI with three-dimensional (3D) and two-dimensional (2D) T(2)-weighted gradient echo (GRE) pulse sequences. Human hMSC labeling without transfection agent was efficient. The iron content in hMSCs was 23.4 pg Fe/cell. No significant change was found in viability, proliferation, MMP change, ROS production, or differentiation capacity. About 45.2% of the hMSCs could be detected using 1.5 T MRI at the single cell level with 3D GRE and four repetitions. 相似文献
55.
Shih-Chieh Hung Kozo Nakamura Ryoji Shiro Kiyokazu Tanaka Hazime Kawahara Takahide Kurokawa 《Journal of orthopaedic research》1997,15(3):381-390
An animal model, using distraction force on adult rabbits, was developed to study the effects of nonweight-bearing on articular cartilage in a moving joint. Histologic evaluation was used to compare the morphology of chondrocytes, safranin O intensity, cartilage thickness, and structural changes between the test and contralateral joints. At 3 and 6 weeks, the chondrocytes in superficial and intermediate zones were round, with an increase in cellular volume density and mean cell volume and with less metachromasia; the safranin O intensity and cartilage thickness were the same as in the controls. In cartilage of the 9-week group, mean cell volume decreased with cell cloning in the superficial zone, while numerical density increased and mean matrix volume per cell decreased in the superficial and intermediate zones. The cartilage, with a 34% reduction in thickness and a 53–72% decrease in safranin O intensity from the superficial to the deep zone, had superficial fibrotic proliferation, suface erosion or depression, ard tidemark irregularity. Continuous distraction in a moving joint caused morphological changes in chondrocytes prior to degeneration of cartilage. These results support the hypothesis that the forces perceived by cells may dictate their shape and then stimulate alterations in cellular biochemistry and matrix metabolism. 相似文献
56.
57.
Jia-You Fang Yann-Lii Leu Tsong-Long Hwang Hsiao-Chin Cheng Chi-Feng Hung 《European journal of pharmaceutical sciences》2003,19(4):253-262
To improve the drug permeation into and/or across the skin, essential oils extracted from Alpinia oxyphylla (AO) were evaluated using in vitro and in vivo permeation techniques with Wistar rats as the animal model. Hydrocarbons and oxygenated sesquiterpenes were the major components in the lower-polarity fraction (AO-1) and higher-polarity fraction (AO-2), respectively. Permeation of indomethacin was significantly enhanced after treatment with AO-1 and AO-2 in the in vitro and in vivo studies. AO-2 generally showed a higher ability to promote drug permeation compared to AO-1. The increment of skin/vehicle partitioning may be the predominant mechanism for this enhancing activity. Both transepidermal water loss (TEWL) and colorimetric evaluation showed limited irritation to skin by AO essential oils at the macroscopic level. Human skin fibroblasts were used to investigate the in vitro screening of skin toxicity. AO-1 slightly increased prostaglandin E(2) (PGE(2)) formation from skin fibroblasts. A striking result was observed with AO-2, which greatly inhibited the release of PGE(2). Moreover, both AO essential oils had no statistically significant effect on PGE(2) release by human lung epithelial cells. The results of this study indicate that skin disruption and inflammation do not necessary correspond to the enhancing efficiency of the enhancers tested. 相似文献
58.
Yuh-Fang Chen Chang-Hao Yang Por T Hung 《Journal of ocular pharmacology and therapeutics》2003,19(5):417-423
This was a 6-week, parallel, randomized, double-blind study comparing the efficacy and safety of the 0.5% timolol/2.0% MK-507 combination b.i.d. to the concomitant administration of 0.5% timolol b.i.d. and 2.0% MK-507 b.i.d. Patients with ocular hypertension or open-angle glaucoma from 21 to 85 years of age were enrolled in this study. Each of them should have intraocular pressure (IOP) of 20 mmHg or more in the study eye after they completed the wash-out period. The patients enrolled were randomly assigned to either combination (0.5% timolol/2.0% MK-507 b.i.d. and placebo b.i.d.) or concomitant (0.5% timolol b.i.d. and 2.0% MK-507 b.i.d.) treatment. During the study, no systemic or topical medication affecting IOP other than test drugs were allowed. A total of 20 randomized patients were included in the intention-to-treat population for analysis of data. The ten were assigned to the combination treatment and others were assigned to the concomitant treatment. There was no statistically significant difference between the two study treatments in terms of gender distribution, average age, and average IOP at the trough and the peak before starting the test medications. Mean reduction of the IOP from baseline to the final visit at the trough was 5.04 mmHg in the combination treatment and was 2.73 mmHg in the concomitant treatment. Mean reduction of the IOP at the peak was 2.19 mmHg in the combination treatment and was 2.53 mmHg in the concomitant treatment. There were no statistically significant differences in the above analyses between the two treatments. Safety evaluation was carried out, and number of adverse events in each treatment group did not differ substantially. Ocular signs and symptoms were evaluated in each visit, and all of the between-treatment values were not different significantly, either. Laboratory tests were performed, and showed no significant differences between pre- and post-treatment periods. None of these was found to be clinically serious, either. We concluded that the 0.5% timolol/2.0% MK-507 combination b.i.d. is equivalent in the efficacy of lowering IOP as well as safety compared to the concomitant administration of 0.5% timolol b.i.d. and 2.0% MK-507 b.i.d. in patients with ocular hypertension or open-angle glaucoma. 相似文献
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