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排序方式: 共有372条查询结果,搜索用时 15 毫秒
1.
Relationships of plasma viscosity, coagulation and fibrinolysis to coronary risk factors and angina 总被引:1,自引:0,他引:1
G D Lowe D A Wood J T Douglas R A Riemersma C C Macintyre T Takase E G Tuddenham C D Forbes R A Elton M F Oliver 《Thrombosis and haemostasis》1991,65(4):339-343
Plasma viscosity, molecular markers of activated coagulation and fibrinolysis (fibrinopeptides A and B beta 15-42), coagulation factors (fibrinogen and factor VII) and antiplasmins were measured in 529 men aged 35-54 years and related to new angina pectoris (n = 117) and to coronary risk factors in controls without angina (n = 412). Five major risk factors (cigarette-smoking, blood pressure, cholesterol, triglyceride and body mass index) were each associated with increases in plasma viscosity, coagulation factors, and imbalance of coagulation over fibrinolysis (increased ratio of fibrinopeptide A/fibrinopeptide B beta 15-42). Increased viscosity and fibrinogen in smokers were partly reversed in ex-smokers, but the imbalance of coagulation and fibrinolysis persisted. Cholesterol and triglyceride were also associated with increased antiplasmin activity. In men with angina, only fibrinogen was elevated compared to controls. We suggest that increased plasma viscosity and an imbalance of coagulation over fibrinolysis may be mechanisms by which known risk factors promote arterial thrombosis, but are not present in stable angina. 相似文献
2.
3.
This paper describes the tragic case of a young woman who died of cancer of
the colon after successfully donating eggs to her younger sister. Although
there is no direct link between her operation and the subsequent
development of bowel carcinoma, this case imparts a feeling of unease when
seen in conjunction with other cases reported during the last few years. It
is a reminder that little is known of the long-term consequences of some
aspects of assisted conception. Women undergoing ovarian stimulation for
themselves or a matched recipient have the right to be advised, in an
agreed format, that there is some concern about unproven potential risks
from the stimulatory drugs. The safety of egg donors must assume priority
over all other considerations, including lack of donors or any moral
position. The recent decision by the Human Fertilisation and Embryology
Authority (HFEA) to withdraw any form of payment or recompense to egg
donors does not seem to us to be based on a balance of scientific advances,
patient needs and the ethics of gamete supply. They state that the
intention to withdraw payments was implicit in the 1990 Human Fertilisation
and Embryology (HFE) Act. However the Act was based on the Warnock report
made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility
drugs had not yet caused any unease. The Act provided the HFEA with
discretionary powers to issue directions so that the future policies would
be consistent with any emerging new medical evidence. It is imperative that
the HFEA provide convincing evidence on how the current policy of payment
to donors harms society, donors or recipients, and how in the UK the new
policy will improve medical practice in assisted conception. Successful
pilot studies must precede the implementation of any new policy. Failure to
do this could cause irreversible harm to the practice of assisted
conception using donor gametes, which will ultimately be against the basic
aims of the 1990 HFE Act.
相似文献
4.
Rai R Tuddenham E Backos M Jivraj S El'Gaddal S Choy S Cork B Regan L 《Human reproduction (Oxford, England)》2003,18(12):2540-2543
BACKGROUND: Some cases of recurrent miscarriage have a thrombotic basis. Thromboelastography is a rapid, reproducible test of whole-blood haemostasis. METHODS: Thromboelastography was performed in 494 consecutive, non-pregnant women (median age 35 years; range 21-48) with a history of miscarriages at <12 weeks gestation (median 4; range 3-12) and 55 parous women (median age 33 years; range 20-41) with no history of pregnancy loss. The prospective outcome of untreated pregnancies amongst 108 women with recurrent miscarriage was studied. RESULTS: The maximum clot amplitude (MA) (median 66.0 mm; range 48.0-76.0) was significantly higher and the rate of clot lysis (LY30) (median 2.5%; range 0.5-7.8) significantly lower amongst women with recurrent miscarriage compared with controls (MA 61.5 mm; range 50.0-67.0; P = 0.01; LY30 4.9%; range 2.9-9.7; P = 0.01). The pre-pregnancy MA was significantly higher amongst women who subsequently miscarried (median 66.0 mm; range 54.0-73.0) compared with those whose had a live birth (median 61.7 mm; 48.0-71.5; P < 0.01). A pre-pregnancy MA >or=64 mm has a sensitivity of 68% and specificity of 82% to predict miscarriage. CONCLUSIONS: Thromboelastography identifies a subgroup of women with recurrent miscarriage to be in a prothrombotic state outside of pregnancy. Women in such a state are at increased risk of miscarriage in future untreated pregnancies. 相似文献
5.
Anne EG Lenferink Joanne Magoon Christiane Cantin Maureen D O'Connor-McCourt 《Breast cancer research : BCR》2004,6(5):R514
Introduction
This report describes the isolation and characterization of three new murine mammary epithelial cell lines derived from mammary tumors from MMTV (mouse mammary tumor virus)/activated Neu + TβRII-AS (transforming growth factor [TGF]-β type II receptor antisense RNA) bigenic mice (BRI-JM01 and BRI-JM05 cell lines) and MMTV/activated Neu transgenic mice (BRI-JM04 cell line). 相似文献6.
OBJECTIVE: To assess the antibody response to influenza vaccine of children vertically infected with HIV. DESIGN: Prospective study in HIV infected children vaccinated during the winter of 1994-5. SETTING: Family HIV clinic at St Mary's Hospital, Paddington. SUBJECTS: 25 children, aged 1-11 years, vertically infected with HIV. MAIN OUTCOME MEASURES: Responses to influenza antigens (H1N1-A/Taiwan/1/86, H3N2-A/Shandong/9/93, B/Panama/45/ 90) were tested by haemagglutination inhibition. Antibody responses were assessed according to clinical symptoms and immune function, stratified according to the 1994 revised classification for HIV infection in children. RESULTS: 23 children (92%) had either very low or no detectable antibody before vaccination. New protective antibody responses were made by 10 children (40%): in seven to a single antigen, in two to two antigens, and in one to all three antigens. For each antigen there was an overall small increase in the mean geometric titre of antibody produced, but this only reached a protective level for antigen H1N1 and for children with minimal symptoms. Less symptomatic children were significantly more likely to produce a protective antibody response to influenza vaccination. No association was found between immune function, as measured by CD4 count, and vaccine response. CONCLUSIONS: Only vaccination of the least symptomatic HIV infected children against influenza is likely to be effective. This will not only protect them against influenza, but will also protect other more immunosuppressed and vulnerable members of their families. 相似文献
7.
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress. 相似文献
8.
F. Bernardi D. L. Liney P. Patracchini D. Gemmati C. Legnani P. Arcieri M. Pinotti R. Redaelli G. Ballerini S. Pemberton A. I. Wacey G. Mariani E. G. D. Tuddenham G. Marchetti 《British journal of haematology》1994,86(3):610-618
Summary. The molecular defects causing CRM+ factor VII deficiency were investigated in seven unrelated subjects and several members of their families.
Four missense mutations located in the catalytic domain of factor VII were found. The previously reported304 ArgGln substitution was present in the homozygous and heterozygous forms, with different polymorphic haplotypes, thus demonstrating that it is recurrent and frequent in the Italian population. The 310 Cys Phe substitution was found in the homozygous form and in the compound heterozygous condition with the nonsense mutation 356 Trpstop. Two missense mutations, 298 MetIle and 342 GlyArg, were found in the homozygous and in the heterozygous condition respectively.
Molecular heterogeneity was further increased by finding of the353 ArgGln polymorphism in the doubly heterozygous condition with the 304 and 342 mutations.
Plausible explanations for loss of FVII function were found by inspecting a model of the serine protease domain of factor VIIa. Inefficient activation of the catalytic site is predicted for298 MetIle. 342 GlyArg would directly distort the geometry of the 'oxyanion hole'preventing formation of a substrate enzyme intermediate. 310 Cyshe is predicted to have an adverse effect on tissue factor interaction. These mutations point to important regions of the factor VII molecule. 相似文献
Four missense mutations located in the catalytic domain of factor VII were found. The previously reported
Molecular heterogeneity was further increased by finding of the
Plausible explanations for loss of FVII function were found by inspecting a model of the serine protease domain of factor VIIa. Inefficient activation of the catalytic site is predicted for
9.
10.
To determine changes in Factor VIII (FVIII) and von Willebrand Factor (VWF) in the first 3 days of the puerperium. A prospective study assessing FVIII clotting activity, VWF activity and antigen levels in 95 women (with singleton uncomplicated pregnancies) during labour and on days 1, 2 and 3 of the puerperium. There were no significant differences in FVIII, VWF:Ag and VWF:CB on days 1 and 2 of the puerperium compared with levels during labour. There was a significant decrease in VWF:Ag (P = 0.009) and VWF:CB (P = 0.04) on day 3. Age, ethnicity, duration of labour and mode of delivery did not have any significant effect on the changes in FVIII and VWF levels. The pregnancy induced increase in FVIII and VWF is maintained in the first 48 h after delivery. VWF levels start to decline on day 3 postdelivery. 相似文献