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141.

Purpose  

The size of the perivitelline space and the incidence of polyspermy were observed in ovulated and cultured oocytes from rabbits and hamsters with or without treatment by 4-methylumbelliferone (MU), an inhibitor of hyaluronic acid (HA) synthase, in order to examine the relationship between the incidence of polyspermy and the size of the perivitelline space. The amount of HA in the medium with MU-treated hamster oocytes was measured and compared with that in the medium with untreated oocytes.  相似文献   
142.
Restrictive cardiomyopathy (RCM) is characterized by irreversible diastolic dysfunction with preserved systolic function. The aim of this study was to investigate the presence of impaired ventricular contractility even in the presence of normal ejection fraction (EF) in children with RCM. Longitudinal Doppler tissue velocities were obtained from apical 4-chamber view at three locations—the left-ventricular (LV) lateral wall, the septum, and the right ventricle—in 8 children age 3–17 years old with RCM who had LV EF >55%. Peak systolic velocity (S′), acceleration during isovolumic contraction (IVA), and myocardial performance index (MPI) were measured. Data from the RCM group were compared with those from 24 age- and sex-matched controls. Both S′ and IVA were markedly lower at the septum (S′ 6.2 ± 1.7 vs. 9.2 ± 1.6, P < 0.001; IVA 1.8 ± 0.5 vs. 3.9 ± 1.5, P < 0.001). MPI, a measure of both diastolic and systolic function, was statistically significantly greater in the RCM group at all 3 locations (P < 0.005). S′ and IVA identify global subclinical systolic dysfunction in RCM with normal EF. These findings suggest that pre-ejection abnormality and subclinical systolic dysfunction coexist with diastolic dysfunction in children with RCM.  相似文献   
143.
OBJECTIVE: To explore the extent to which clinical characteristics influence the association between cyclooxygenase 2 inhibitors (coxibs) and/or nonselective nonsteroidal antiinflammatory drugs (NSAIDs) and increased cardiovascular disease (CVD) risk in specific patient subgroups. There is substantial concern regarding the potential cardiovascular adverse effects of selective coxibs and nonselective NSAIDs, but many patients with arthritis experience important clinical benefits from these agents. METHODS: The study population consisted of Medicare beneficiaries also eligible for a drug benefits program for older adults during the years 1999-2004. We calculated the relative risk (RR) for CVD events (myocardial infarction [MI], stroke, congestive heart failure, and cardiovascular death) among users of coxibs or nonselective NSAIDs in the prior 6 months compared with nonusers. We assessed biologic interaction between these medication exposures and important patient characteristics. RESULTS: In the primary cohort, we identified 76,082 new users of coxibs, 53,014 new users of nonselective NSAIDs, and 46,558 nonusers. Compared with nonusers, the adjusted RR of CVD events for new users of each agent increased for rofecoxib (RR 1.22, 95% confidence interval [95% CI] 1.14, 1.30) and decreased for naproxen (RR 0.79, 95% CI 0.67, 0.93). Several patient characteristics were found to increase the risk of CVD events among users of some agents in both the primary and secondary cohorts, including age >/=80 years, hypertension, prior MI, prior CVD, rheumatoid arthritis, chronic renal disease, and chronic obstructive pulmonary disease. Rofecoxib and ibuprofen appeared to confer an increased risk in multiple patient subgroups. CONCLUSION: Many nonselective NSAIDs and coxibs are not associated with an increased risk of CVD events. However, several patient characteristics identify important subgroups that may be at an increased risk when using specific agents.  相似文献   
144.
The present study surveyed the sleep habits of 3-year-old children in Asahikawa city using questionnaires completed by a parent during children's medical check-ups. Questionnaires were collected from the parents of 404 children (209 males, 195 females; mean age, 3.1 years) enrolled in this survey. Among these children, the mean bedtime was 9.6 PM with 145 children (36%) going to bed after 10 PM. On the other hand, the mean wake-up time was 7.5 AM, with 123 children (30%) waking up after 8 AM. The mean nocturnal sleep duration was 10.1 hours. Nocturnal sleep durations in children that went to bed after 10 PM were significantly shorter than in children who went to bed earlier (p < 0.01). Seventy-three percent of the children had a daily afternoon nap. Twelve percent of these children usually awoke from their nap after 5 PM, and the mean bedtime for these children was 10.1 PM. A late bedtime was significantly correlated with parental complaints such as short-temper and poor appetite (p < 0.05). Although parents were concerned about night-time sleep conditions, they were not concerned about the daytime conditions which regulate children's sleep-wake rhythm, such as daylight exposure, daytime activity, and naps. While 24% of parents had complains regarding their children's sleep, only 3% had consulted with a doctor. Similar to the previous reports, the present findings demonstrate that children in Asahikawa city go to bed late and have decreased sleep duration. Since the establishment of a normal sleep-wake rhythm is essential for both physical and mental development in children, it is necessary to educate parents regarding the importance of children's sleep.  相似文献   
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146.
The authors managed five LOS patients using prolonged V-A bypass circulatory assist. Maximum CVP values were under 12 mmHg in three survivors, and 17 mmHg and 20 mmHg in two nonsurvivors. Maximum PCWP values were under 14 mmHg in survivors, and 19 mmHg and 20 mmHg in nonsurvivors. Dopamine was administrated in all cases and norepinephrine was administrated at a rate of less than 0.3 microgram.kg-1.min-1 in survivors, and in two nonsurvivors, norepinephrine was used at a rate of 0.36 and 1.2 micrograms.kg-1.min-1. Before and after disconnection of V-A bypass, the bypass flow of the three survivors were under 1.0 l.min-1 just before disconnection, and immediately after it, the preload did not increase, and the dose of administrated catecholamine increased. V-A bypass time intervals of the three survivors were 71, 42 and 87 hours, and those of the two nonsurvivors were 71 and 43 hours. Maximum bypass flow rate was above 40ml.kg-1.min-1 in four of five patients. The authors discussed the management of the patients' heart and of the V-A bypass machine during the prolonged V-A bypass circulatory assist.  相似文献   
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148.
OBJECTIVE--To quantitatively assess atherosclerosis of the carotid artery in subjects with and without diabetes. RESEARCH DESIGN AND METHODS--Ultrasound high resolution B-mode imaging of carotid arteries was conducted on 71 nondiabetic subjects without hyperlipidemia or hypertension and 295 diabetic patients to determine IMT of the arterial wall. RESULTS--IMT was linearly related with age in nondiabetic (IMT = [0.0087 x age] + 0.3318) and diabetic subjects (IMT = [0.0155 x age] + 0.32450). The regression coefficient for age was significantly greater in diabetic than nondiabetic subjects. IMT (mean +/- SD) of diabetic subjects aged 20-29 was significantly greater than that of nondiabetic subjects aged 20-29 (0.73 +/- 0.27 vs. 0.52 +/- 0.07 mm, P less than 0.01). Multivariate regression analysis of 275 NIDDM patients indicated smoking, hyperlipidemia, duration of diabetes, hypertension, and age were factors determining thickness of the carotid arterial wall. CONCLUSIONS--Diabetes, along with age, hyperlipidemia, smoking, and hypertension, aggravates carotid atherosclerosis.  相似文献   
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