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排序方式: 共有947条查询结果,搜索用时 31 毫秒
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Golli M; Van Nhieu JT; Mathieu D; Zafrani ES; Cherqui D; Dhumeaux D; Vasile N; Rahmouni A 《Radiology》1994,190(3):741
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Inter-cohort differences in coronary heart disease mortality in the 25-year follow-up of the seven countries study 总被引:2,自引:0,他引:2
A. Menotti A. Keys D. Kromhout H. Blackburn C. Aravanis B. Bloemberg R. Buzina A. Dontas F. Fidanza S. Giampaoli M. Karvonen M. Lanti I. Mohacek S. Nedeljkovic A. Nissinen J. Pekkanen S. Punsar F. Seccareccia H. Toshima 《European journal of epidemiology》1993,9(5):527-536
Sixteen cohorts of men aged 40–59 years at entry were examined with the measurement of some risk factors and then followed-up for mortality and causes of death for 25 years. These cohorts were located in the USA (1 cohort), Finland (2), the Netherlands (1), Italy (3), the former Yugoslavia (5), Greece (2), and Japan (2), and included a total of 12,763 subjects.Large differences in age-adjusted coronary heart disease (CHD) death rates were found, with extremes of 45 per 1000 in 25 years in Tanushimaru, Japan, to 288 per 1000 in 25 years in East Finland. In general, higher rates were found in the US and Northern European cohorts as compared to the Southern European and Japanese cohorts. However, during the last 10 years of follow-up large increases of CHD death rates were found in some Yugoslavian areas. Out of 5 measured entry characteristics treated as age-adjusted levels (serum cholesterol, systolic blood pressure, cigarette smoking, body mass index and physical activity at work), only serum cholesterol was significant in explaining cohort differences in CHD death rates.Over 50% of the variance in CHD death rates in 25 years was accounted for by the difference in mean serum cholesterol. This association tended to decline with increasing length of follow-up, but this was due to the great changes in mean serum cholesterol in the two Jugoslavian cohorts of Velika Krsna and Zrenjanin. When these two cohorts were excluded the association increased with time.Changes in mean serum cholesterol between year 0 and 10 helped in explaining differences in CHD death rates from year 10 onward.It can be concluded that this study suggests that mean serum cholesterol is the major risk factor in explaining cross-cultural differences in CHD. 相似文献
5.
MGC Hendriks P Dogterom JT Ebels B Oosterhuis LR Geertsema T Hulot G Bianchetti and JHG Jonkman 《Fundamental & clinical pharmacology》1998,12(5):559-565
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated. 相似文献
6.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
7.
Hallikainen T Lachman H Saito T Volavka J Kauhanen J Salonen JT Ryynänen OP Koulu M Karvonen MK Pohjalainen T Syvälahti E Hietala J Tiihonen J 《American journal of medical genetics》2000,96(3):348-352
Addictive drugs, including ethanol, increase the brain's dopaminergic transmission, and catechol-o-methyltransferase (COMT) enzyme has a crucial role in dopamine inactivation. A common functional polymorphism in the COMT gene results in a three- to four-fold variation in enzyme activity. In a previous study, we found an association between type 1 (with late-onset but without prominent antisocial behavior) alcoholism and the low activity allele of the COMT gene. In this work we analyzed whether the COMT polymorphism has any effect on the development of type 2 (with early-onset and habitual impulsive violent behavior) alcoholism. The COMT genotype was determined in 62 impulsive violent recidivist offenders with early-onset (type 2) alcoholism, 123 late-onset nonviolent (type 1) alcoholics, and 267 race and gender-matched controls. The allele and genotype frequencies of these groups were compared with each other and also with previously published data from 3,140 Finnish blood donors. The type 2 alcoholics did not differ from either the blood donors or the controls. The low activity (L) allele frequency was higher among type 1 alcoholics (chi(2) = 4.98, P = 0.026) when compared with type 2 cases. The odds ratio for type 1 alcoholism as compared with type 2 alcoholism for those subjects with the LL genotype versus the HH genotype was 3.0 (95% confidence interval 1.1-8.4, P = 0.017). The results suggest that COMT genotype has no major role in the development of early-onset alcoholism with severe antisocial behavior. 相似文献
8.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
9.
The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen 总被引:19,自引:2,他引:19
Manning JT; Scutt D; Wilson J; Lewis-Jones DI 《Human reproduction (Oxford, England)》1998,13(11):3000-3004
The differentiation of the urinogenital system and the appendicular
skeleton in vertebrates is under the control of Hox genes. The common
control of digit and gonad differentiation raises the possibility that
patterns of digit formation may relate to spermatogenesis and hormonal
concentrations. This work was concerned with the ratio between the length
of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in
right and left hands has a sexually dimorphic pattern; in males mean 2D:4D
= 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females
mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal
length. The dimorphism is present from at least age 2 years and 2D:4D is
probably established in utero; (ii) high 2D:4D ratio in right hands was
associated with germ cell failure in men (P = 0.04); (iii) sperm number was
negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men
testosterone concentrations were negatively related to right hand 2D:4D and
in women and men LH (right hand), oestrogen (right and left hands) and
prolactin (right hand) concentrations were positively correlated with 2D:4D
ratio and (v) 2D:4D ratio in right hands remained positively related to
luteinizing hormone and oestrogen after controlling for sex, age, height
and weight.
相似文献
10.