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The effect of prostaglandin E1 (PGE1) on platelets is mediated through the PGE1 receptor and the consequent maintenance of the platelet's discoid shape. The effects of PGE1 and dibutyryl cAMP (dbcAMP) on the deformability of human platelets were studied. Deformability tests based upon the micropipette aspiration on the platelets were performed by using pipettes with radii (Rp) of 0.26-0.36 gm. The time course of the extension length (Dp, in μg) of the platelets in response to aspiration with a negative pressure (ΔP) of 5 cm H2 O (ΔP × Rp = 0.15 dynes/cm) was analyzed. PGE1 treatment (0.1 μM) resulted in a decrease of platelet deformability as compared with results obtained for apparently non-activated, control platelets. The deformation index, i.e., Dp/Rp (PGE1 -treated) / Dp/Rp (control), was significantly reduced to 0.90 ± 0.04. DbcAMP treatment also significantly decreased the deformability of platelets and this decrease was dbcAMP dose dependent. In contrast, colchicine- or cytochalasin D-treated platelets increased deformability. PGE1 -treated platelets had a higher [cAMP]i than controls. Platelets treated with PGE1 or dbcAMP showed a reduced [Ca2+]i increment induced by thrombin as compared to non-treated controls. These results indicate that PGE1 and dbcAMP treatment of platelets is accompanied by an enhancement of platelet resistance to deformation. The increased [cAMP]i and low [Ca2+]i after PGE1 treatment may limit the rearrangement of cytoskeleton and thus enhance platelet resistance to deformation. 相似文献
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Chih-Hung Chien Tzong-Yang Tu Shu-Feng Chien Angela Chung-I Li Mei-Jan Yang An-Suey Shiao Yi-Fen Wang 《台湾医志》2006,105(10):832-838
BACKGROUND/PURPOSE: In the geriatric population, the reliability of pure-tone threshold (PTT) is sometimes poorer than that in young adults because of various reasons. This study assessed the relationship between Mandarin speech reception thresholds (SRTs) and PTTs in the aged and developed SRT as a measure for corroborating PTT. METHODS: This prospective study enrolled 46 consecutive subjects over 60 years of age. The results of SRT and PTT were collected from one ear randomly selected from each subject. Simple linear and multiple regressions were used to determine the correlation and linear regression coefficients between SRTs and PTTs at various frequencies. RESULTS: In the simple regression analysis, the correlation coefficient was highest at 1000 Hz (r = 0.949) and 500 Hz (r = 0.922), followed by 250 Hz (r = 0.850) and 2000 Hz (r = 0.792). In the multiple regression model with SRT as the dependent variable and PTTs as predictor variables, the resultant multiple correlation coefficient R was 0.967, while R2 was 0.936. In this model, PTTs at the frequencies of 500 Hz and 1000 Hz contributed significantly to the variance in SRTs with p values of 0.029 and < 0.001, respectively. These results demonstrated that the Mandarin SRT is strongly associated with PTTs at the frequencies of 500 Hz and 1000 Hz. CONCLUSION: This study established the agreement between Mandarin SRTs and PTTs in the low tone area of speech frequencies in the geriatric population. In clinical settings, SRT test can be rapidly and easily performed and is relatively inexpensive. It is a vital indicator of the accuracy of PTT measurement. 相似文献
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T C Andy 《The Central African journal of medicine》1990,36(10):246-250
This paper reports a 1986 house interview survey which was carried out on Cicia, an Island in Fiji, for a two-week recall period, 14 pc of the studied population of 471 inhabitants reported symptoms or illnesses, with variations related to age. Almost half 48 pc of those who reported symptoms sought medical care in the health centre. Most of those who sought medical care were mostly around the centre. It appears necessary to provide care to those in the distance villages either by opening satellite clinics visited by the medical assistant several times a month or train a local resident to provide appropriate first aid. 相似文献
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Jiunn-Tat Lee Li-Fu Cheng Chih-Ming Lin Chien-Hsing Wang Chieh-Chi Huang Sou-Hsin Chien 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(9):1060-1066
We describe island pedicled anterolateral thigh and vastus lateralis myocutaneous flaps for reconstruction of the difficult, recurrent ischial pressure sore. Rather than transfer through a subcutaneous tunnel, the flap is transferred directly through the upper thigh to the ischial defect. A total of 15 patients with 16 recurrent ischial pressure sores were treated between May 2003 and April 2005. Eleven sores were treated with pedicled island anterolateral thigh flaps and five sores with vastus lateralis myocutaneous flaps. There was no difficulty in transferring the flap to reach the ischial defect in any patient. The length of the pedicle ranged from 8.5 to 14 cm. All donor sites were closed primarily. Fifteen of the 16 flaps survived completely. Total necrosis occurred in one vastus lateralis myocutaneous flap, which was located at the distal third of the thigh. We conclude this flap can be added to the repertoire for the treatment of recurrent, difficult ischial pressure sores. 相似文献
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This pilot study compared abdominal massage with laxative treatment in the management of constipation in 32 profoundly disabled, institutionalised adults. A randomised cross-over design was used. After an initial 16-day baseline measurement phase without any treatment, there followed two seven-week treatment phases separated by a one-week washout period. Each subject received seven weeks of massage and seven weeks on his or her previous laxative regimen. Primary outcome measures were gastro-intestinal and segmental transit times, measured at the end of the baseline phase and of each treatment phase. Secondary measures included stool frequency, size and consistency, the requirement for enemas and an assessment of patient well-being.The median value of total colonic transit time was 183 hours for the baseline phase and 159 hours for all treatment phases. There was no evidence of any statistically significant treatment differences between laxative and massage therapy for right, left or rectosigmoid segments either separately or in total. Analysis of secondary outcome measures also failed to find any treatment preferences.These results reveal the grossly abnormal colonic transit times of the study population at all times. The effects of laxative and massage therapy within this environment were not demonstrably different. 相似文献