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21.
Congenital lobar emphysema, a life-threatening respiratory disorder presenting in infancy is best diagnosed by chest x-ray. Abnormality of bronchial cartilage is one of the suspected aetiological factors. Prompt lobectomy is the treatment of choice as conservative treatment carries an unacceptably high mortality and morbidity. One such patient, a 3-month-old child who underwent successful emergency left upper lobectomy is presented.  相似文献   
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Thrombopoietin (Tpo), the ligand for c-mpl, has been shown to be the principal regulator of megakaryocytopoiesis and platelet production. The ability of Tpo to potently stimulate the growth of committed megakaryocyte (Mk) progenitor cells has been studied in detail. Murine fetal liver cells, highly enriched in primitive progenitors, have been shown to express c-mpl, but little is known about the ability of Tpo to stimulate the growth and differentiation of primitive multipotent bone marrow (BM) progenitor cells. Here, we show that Tpo alone and in combination with early acting cytokines can stimulate the growth and multilineage differentiation of Lin- Sca-1+ BM progenitor cells. In particular, Tpo potently synergized with the ligands for c-kit (stem cell factor [SCF]) and flt3 (FL) to stimulate an increase in the number and size of clones formed from Lin- Sca-1+ progenitors. When cells were plated at 1 cell per well, the synergistic effect of Tpo was observed both in fetal calf serum-supplemented and serum-depleted medium and was decreased if the addition of Tpo to cultures was delayed for as little as 24 hours, suggesting that Tpo is acting directly on the primitive progenitors. Tpo added to SCF + erythropoietin (Epo)-supplemented methylcellulose cultures potently enhanced the formation of multilineage colonies containing granulocytes, macrophages, erythrocytes, and Mks. SCF potently enhanced Tpo-stimulated production of high-ploidy Mks from Lin- Sca-1+ progenitors, whereas the increased growth response obtained when combining Tpo with FL did not translate into increased Mk production. The ability of Tpo and SCF to synergistically enhance the growth of Lin- Sca-1+ progenitors was predominantly observed in the more primitive rhodamine 123(lo) fraction. Tpo also enhanced growth of Lin- Sca-1+ progenitors when combined with interleukin-3 (IL-3) and IL-11 but not with IL-12, granulocyte colony-stimulating factor, granulocyte-macrophage colony- stimulating factor, or Epo. Epo, which has high homology to Tpo, was unable to stimulate the growth of Lin- Sca-1+ progenitors alone or in combination with SCF or FL, suggesting that c-mpl is expressed on more primitive stages of progenitors than the Epo receptor. Thus, the present studies show the potent ability of Tpo to enhance the growth of primitive multipotent murine BM progenitors in combination with multiple early acting cytokines and documents its unique ability to synergize with SCF to enhance Mk production from such progenitors.  相似文献   
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BACKGROUND: Limited evidence suggests that maternal undernutrition at the time of conception is associated with increased cardiovascular disease risk in adult offspring. OBJECTIVE: We investigated whether persons conceived during the Dutch famine of World War II had an early onset of coronary artery disease (CAD). DESIGN: We compared the age at onset and cumulative incidence of CAD between persons born as term singletons who were exposed to the 1944-1945 Dutch famine during late (n = 160), mid- (n = 138), or early (n = 87) gestation and 590 unexposed subjects at age 50 or 58 y. Age at CAD onset was defined as the age at which angina pectoris was identified (according to the Rose questionnaire), Q waves were observed on an electrocardiogram (Minnesota codes 1-1 or 1-2), or coronary revascularization was performed (by angioplasty or bypass surgery). RESULTS: Of the 83 CAD cases identified, persons conceived during the famine were 3 y younger than the unexposed persons at the time of CAD diagnosis (47 y compared with 50 y) and had a higher cumulative incidence of CAD [13%; hazard ratio (HR) adjusted for sex: 1.9; 95% CI: 1.0, 3.8] than did the unexposed persons. The HR changed little after adjustment for smoking (HR: 1.8), social class (HR: 2.0), or size at birth (HR: 2.0). CONCLUSIONS: We found an earlier onset of CAD among persons conceived during the famine, which suggests that maternal nutrition in early gestation may play a role in the onset of CAD. This finding agrees with evidence from animal experiments that identify periconceptional maternal diet as important in the offspring's adult health.  相似文献   
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OBJECTIVE: To study the attitude of Dutch women to the offer and subsequent (non)use of nuchal translucency (NT) screening for Down syndrome in the first trimester of pregnancy, in a country where screening is not routinely offered under 36 years of age. METHODS: An experimental NT screening programme offered to pregnant women, together with a series of questionnaires to be completed before and after the offer and (non)use of screening, in 12 midwife practices in three different health districts. PARTICIPANTS: Cohort of pregnant women who had their first prenatal care visit in the participating midwife practices between 1 June 1999 and 1 January 2001. MAIN OUTCOME MEASURES: Women's knowledge and understanding of prenatal screening tests; attitude towards screening offer; perceived freedom of choice; satisfaction with information given; change in attitude over time. RESULTS: Eighty-six percent of women accepted the offer of NT screening. Seventy percent had previous knowledge of NT screening and 92% considered the information given before screening clear and sufficient. Thirty-nine percent of women felt worried to some extent after being given the information, but only 3% would have preferred not to have been informed at all. Ninety percent of women (including 68% of decliners) agree that information on Down syndrome screening should be extended to all pregnant women and feel competent in deciding on screening participation. CONCLUSION: When NT screening is offered as a new screening strategy its concept is understood and well accepted. The large majority of women, including the decliners, are in favour of its standard offer.  相似文献   
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OBJECTIVE: To determine whether there were any recent changes in hepatitis B immunisation of dental staff, infection control or understanding of viral infections in Brazilian dentists.
DESIGN: A randomised survey was conducted on 740 dentists attending the National Dental Congress in Sao Paulo, Brazil in 1994.
SUBJECTS AND METHODS: The 740 dentists were questioned as to the presence of various viruses in saliva, the perceived risks of dental staff and long-term sequelae, the availability and uptake of vaccines, willingness to treat virus-infected persons, and means of infection control. Nearly 69% of respondents were female dentists, of mean age 30 years. Results were compared with a similar survey from 1990.
RESULTS: Most respondents knew that HIV and hepatitis viruses could appear in saliva and almost all knew of infective risks from hepatitis B (HBV), and the availability of the vaccine. Less than half knew of the association of HBV with liver cancer. There was a four-fold increase in those vaccinated against HBV since the low figure of 9% in 1990. Nearly two-thirds of respondents perceived an occupational risk to dental staff from HIV, and a similar proportion were also unwilling to treat virus-infected persons. A similar proportion also used chemical disinfection for some dental instruments.
CONCLUSIONS: The results show little improvement over a 4-year period except a much greater proportion of dentists were immunised against HBV. However, still only one third of dentists had been vaccinated, in a country with a high prevalence of infection in the general population.  相似文献   
27.

Background

Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on echocardiographic indices of systolic and diastolic left ventricular function.

Methods

Fifty one obese and 25 normal weight, serving personnel without any other pathological condition were studied. Group I (n=25) consisted of subjects with normal weight and body mass index (BMI <25kg/m2), Group II (n=34) of overweight subjects (BMI 25-29.9 kg/m2) and Group III (n=17) of obese subjects (BMI >30 kg/m2). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by ≥ 2 SD from the normal weight group.

Result

Ejection fraction, fractional shortening were increased (p<0.05) in Group II and III. Left ventricular dimensions were increased (p< 0.001) but relative wall thickness was unchanged. Systolic dysfunction was not observed in any of the obese patients. The mitral valve pressure half time (p< 0.01), left atrial diameter (p < 0.01) and the deceleration time were increased (p< 0.01) in obese subjects, while other diastolic variables were unchanged. No difference were found between obesity subgroups. Subclinical diastolic dysfunction was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function.

Conclusion

Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.Key Words: Obesity, Systolic function, Diastolic function, Echocardiography  相似文献   
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An 18-year old patient bearing a subcutaneous Norplant implant in the left upper arm for 2 years visited a gynecological clinic. The implant rods were removed under local anesthesia because of the increasing pigmentation of the skin, and she switched to oral contraceptive use. Norplant contains a total of 216 mg of levonorgestrel (LNG) in 6 silastic rods, each 3.4 cm long. Norplant-2 consists of 3 rods with a length of 4.4 cm providing a total of 140 mg of LNG. It has been in use since 1974 in Chile, and subsequently in Brazil, Indonesia, Thailand, Africa, and to a lesser extent in Scandinavia. It works via the continuous release of 30-50 mcg doses of progesterone daily that induces cervical mucous changes whereby sperm penetration is thwarted; nidation does not occur, and ovulation is also often inhibited. The Pearl-Index reaches .1-1.1 in the first 5 years of use. The most important side effects are menstruation changes (oligo- and amenorrhea), weight gain, and headache. The continuation rate is similar to that of the IUD: 95% through the 1st year of use, and 75% through 3 years reported from Chile and China. Reversibility is a major advantage: 50% of women become pregnant within 3 months after removal, 86% within 1 year, and 93% within 2 years. In the Netherlands sits acceptance is clearly distinct from prevalence in Chile and China, and it has only a minor role in applicability when other contraceptives fail.  相似文献   
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