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The authors studied the distribution of lipoprotein(a) (Lp(a)) levels with stratification for age and sex, as well as the relation between Lp(a) and atherosclerotic risk factors in a large Japanese population between 1992 and 1993. The subjects were 1,235 males and 1,762 females over 30 years old. Lp(a) was measured by an enzyme-linked immunosorbent assay. Lp(a) levels were higher in females than in males. The increase in Lp(a) with age was statistically significant, and the proportion of subjects with Lp(a) levels > 30 mg/dl also increased with age. In the obese subjects (body mass index (BMI) (kg/m2) > 26), Lp(a) levels were lower than in the non-obese subjects (BMI < or = 26) (p < 0.01 in males; p < 0.05 in females). Male alcohol drinkers had lower Lp(a) levels than nondrinkers (p < 0.05). Age, low density lipoprotein subtracting Lp(a) cholesterol [Lp(a) x 0.3], and fibrinogen level were all positively correlated with Lp(a) in both sexes. Alcohol consumption (g/day) and triglycerides were inversely correlated with Lp(a) in males, while total cholesterol subtracting Lp(a) cholesterol [Lp(a) x 0.3], high density lipoprotein, and factor VII were positively correlated in females. Multiple logistic regression analysis showed that triglycerides in males and BMI and fibrinogen in females were significant independent variables. The authors conclude that Lp(a) level is affected by various factors, such as alcohol drinking, BMI, sex, and age, and is not only correlated with lipid levels but also with hemostatic factors such as fibrinogen and factor VII.  相似文献   
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OBJECTIVE: The aim of this study was to investigate the relationships between levels of natriuretic peptides and adrenomedullin and 24 h blood pressure levels in elderly hypertensives. DESIGN AND METHODS: We performed both 24 h ambulatory blood pressure monitoring and measurement of plasma levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and adrenomedullin in 118 asymptomatic hypertensive elderly (> 60 years old) patients. We classified the subjects into groups with isolated clinic hypertension (n = 40) and sustained hypertension (n = 78). We also measured the levels of these peptides in 37 elderly normotensive subjects. RESULTS: Plasma ANP and BNP levels were slightly increased in patients with isolated clinic hypertension compared with elderly normotensives. Among the hypertensives, plasma ANP and BNP levels were more closely related to 24 h blood pressure levels than to office blood pressure levels. Sustained hypertensives showed significantly increased plasma levels of ANP and BNP compared with isolated clinic hypertensives, while adrenomedullin levels were similar in the two groups. Elderly hypertensives with left ventricular hypertrophy detected by electrocardiography had significantly higher levels of ANP and BNP, and higher BNP/ANP ratios than those without left ventricular hypertrophy, while there was no significant difference in adrenomedullin levels between the two groups. CONCLUSIONS: Our results suggest that measurements of ANP and BNP may be useful in detecting left ventricular hypertrophy and in differentiating isolated clinic hypertension from sustained hypertension in elderly hypertensive patients.  相似文献   
4.
On the basis of our reported experience with colchicine for recurrent pericarditis, we administered colchicine to two patients with large pericardial effusions complicating idiopathic pericarditis. The first was a 26-year-old male who showed clinical deterioration following emergency pericardiocentesis and aspirin (3 g/day) for 10 days; the second was a 2-year-old girl who was unsuccessfully treated with aspirin (100 mg/kg/day) for 2 weeks, followed by corticosteroids for 7 months. Administration of colchicine (1 mg/day) instead of aspirin in the first case, and with a rapid tapering-off of the corticosteroids in the second case, led to complete regression of the pericardial effusion on echocardiography within 1 week and 1 month, respectively. Colchicine was discontinued after 1 month in the first patient and was continued for 6 months in the child. Neither has had a recurrence at 24 and 6 months of follow-up, respectively. No side effects of colchicine were observed. We conclude that colchicine may be effective in the treatment of large pericardial effusion when therapy with nonsteroidal anti-inflammatory drugs and/or corticosteroids fails.  相似文献   
5.
To investigate the relationships among diurnal blood pressure (BP) variations and autonomic nervous system dysfunction, we assessed heart rate variability (HRV) using power spectral analysis of the 24-hour RR interval in 51 asymptomatic elderly hypertensive patients with various patterns of nocturnal BP fall. The extreme-dippers with marked nocturnal BP fall (n=16) had lower asleep low-frequency power (LF)/high-frequency power (HF) ratios (a relative index of sympathetic nervous system activity), while the nondippers without nocturnal BP fall (n=18) had lower awake LF/HF ratios and asleep/awake ratio for HF (an index of parasympathetic nervous activity), when compared with dippers with appropriate nocturnal BP fall (n=17). The incidence of multiple lacunar infarction detected by brain magnetic resonance imaging was 56% in the extreme-dippers and 38% in the nondippers, and both were markedly higher than that (6.3%) in the dippers (both P<.01). There was no significant relationship between the BP level and any HRV parameter for either the daytime or nighttime period. The asleep/awake ratio for systolic BP was significantly correlated with the asleep/awake ratio for HF (r= -.363, P<.01) and with the asleep/awake ratio for the LF/HF ratio (r=.540, P<.001), regardless of whether multiple lacunar infarction was present. In conclusion, the autonomic nervous system activity is not related to high BP level per se, rather its diurnal variation is more important as a determinant of the diurnal BP patterns, regardless of the presence or absence of cerebrovascular disease.  相似文献   
6.
Self-organized inorganic nanoparticle arrays on protein lattices   总被引:1,自引:0,他引:1  
Cavities formed by proteins have been utilized as the reaction chamber for the fabrication of a range of inorganic nanoparticles, providing control of the size of particles by limiting growth and preventing agglomeration. In crystal form, proteins construct molecular arrays that can provide regularly arranged sites for nanoparticles. Here we report the fabrication of nanometric iron and indium particles using ferritin, an iron-storage protein. The indium nanoparticles thus formed have uniform spherical shape with diameter of 6.6 +/- 0.5 nm, while the iron nanoparticles are somewhat irregular in shape (5.8 +/- 1.0 nm). Regular two-dimensional arrays of these nanoparticles are successfully produced by crystallizing ferritin molecules on a water-air interface using the denatured protein film method. The lattice constant of these nanoparticle arrays is 13 nm with hexagonal packing, and arrays of more than 1 microm in area can be obtained by transfer onto silicon wafer.  相似文献   
7.
We developed a novel technique for detaching protein crystals from glass capillary tube using the counter diffusion crystallization technique by femtosecond laser irradiation. X-ray diffraction analysis demonstrated that femtosecond laser irradiation has little effect on crystallinity. This technique will contribute to progress in structural genomics as a powerful tool.  相似文献   
8.
烧结厂可见的烧结废气严重影响工厂周围景色。通过详细分析大分厂一号烧结机烧结废气的组分和粉尘,对可见烟气的形成机理进行了讨论。含有硫酸的烧结废气在冷却过程中形成的可见烟气的主要物质为空气中的雾气凝结物。硫酸具有促进雾气凝结和降低可见水雾汽化的作用,废气中的粉尘可作为雾气凝结的凝结核。在名古屋3号烧结机进行的测试验证了这种机理认识,通过将富含SOx的气体与烧结废气重新混合来观察具有长尾迹的可见烟气。总之,要使烧结废气不可见,需要有脱硫设备。  相似文献   
9.
Toxic equivalent (TEQ) levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) and coplanar polychlorinated biphenyls (CoPCBs) were analyzed in both crude (n = 5) and refined-hardening fish oils (n = 2), which are used in part as the raw materials of margarine and shortening, and in some retailed fish (n = 6), which may be similar to those used as sources of fish oil. PCDDs/DFs-TEQ levels ranged from 0.1 to 13.5 pg TEQ/g fat weight in crude fish oils, from 0.5 to 1.6 pg TEQ/g fat weight in refined-hardening fish oils, and ranged from 1.4 to 31.2 pg TEQ/g fat weight in retailed fish. The ranges of PCDDs/DFs-TEQ in crude fish oils, in refined-hardening fish oils and in retailed fish overlapped each other. In addition, CoPCBs-TEQ levels ranged from 4.9 to 19.6 pg TEQ/g fat weight in crude fish oils, from 0.2 to 1.4 pg TEQ/g fat weight in refined-hardening fish oils, and from 2.7 to 165.8 pg TEQ/g fat weight in retailed fish. TEQ levels of CoPCBs in refined-hardening fish oils were much lower than those in crude fish oils and in retailed fish. This was due to the lower concentrations of less-chlorinated congeners in refined-hardening fish oils, as compared to those in crude fish oils and retailed fish. It appears that less-chlorinated PCBs congeners in refined-hardening fish oils are partly removed during the refining process.  相似文献   
10.
The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter. Cross-sectional analyses involving 2190 houses showed that average living room, changing room, and bedroom temperatures were 16.8°C, 13.0°C, and 12.8°C, respectively. Comparison of average living room temperature between prefectures revealed a maximum difference of 6.7°C (Hokkaido: 19.8°C, Kagawa: 13.1°C). Compared to the high-income group, the odds ratio for living room temperature falling below 18°C was 1.38 (95% CI: 1.04-1.84) and 2.07 (95% CI: 1.28-3.33) for the middle- and low-income groups. The odds ratio was 1.96 (95% CI: 1.19-3.22) for single-person households, compared to households living with housemates. Furthermore, lower room temperature was correlated with local heating device use and a larger amount of clothes. These results will be useful in the development of prevention strategies for residents who live in cold homes.  相似文献   
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