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61.
Effectiveness of the WHO/UNICEF guidelines on infant feeding for HIV-positive women: results from a prospective cohort study in South Africa 总被引:2,自引:0,他引:2
Doherty T Chopra M Jackson D Goga A Colvin M Persson LA 《AIDS (London, England)》2007,21(13):1791-1797
BACKGROUND: The World Health Organization (WHO) and UNICEF recommend that HIV-positive women should avoid all breastfeeding only if replacement feeding is acceptable, feasible, affordable, sustainable and safe. Little is known about the effectiveness of the implementation of these guidelines in developing country settings. OBJECTIVE: To identify criteria to guide appropriate infant-feeding choices and to assess the effect of inappropriate choices on infant HIV-free survival. METHOD: Prospective cohort study of 635 HIV-positive mother-infant pairs across three sites in South Africa to assess mother to child transmission of HIV. Semistructured questionnaires were used during home visits between the antenatal period and 36 weeks after delivery to collect data concerning appropriateness of infant feeding choices based on the WHO/UNICEF recommendations. RESULTS: Three criteria were found to be associated with improved infant HIV-free survival amongst women choosing to formula feed: piped water; electricity, gas or paraffin for fuel; and disclosing HIV status. Using these criteria as a measure of appropriateness of choice: 95 of 311 women who met the criteria (30.5%) chose to breastfeed and 195 of 289 women who did not meet the criteria (67.4%) chose to formula feed. Infants of women who chose to formula feed without fulfilling these three criteria had the highest risk of HIV transmission/death (hazard ratio, 3.63; 95% confidence interval, 1.48-8.89). CONCLUSIONS: Within operational settings, the WHO/UNICEF guidelines were not being implemented effectively, leading to inappropriate infant-feeding choices and consequent lower infant HIV-free survival. Counselling of mothers should include an assessment of individual and environmental criteria to support appropriate infant-feeding choices. 相似文献
62.
Thunell L Milsom I Schmidt J Mattsson LA 《BJOG : an international journal of obstetrics and gynaecology》2006,113(1):15-20
OBJECTIVES: To study changes in attitudes, knowledge and management strategies concerning hormone replacement therapy (HRT) among gynaecologists in Sweden. DESIGN: Comparative questionnaire study. SETTING: National survey. POPULATION: Practising gynaecologists. METHODS: In 1996, gynaecologists in Sweden (n= 1323) were invited to return a postal questionnaire concerning their attitudes, knowledge and management strategies concerning HRT. They were also asked about their own use of HRT. In 2003, a similar questionnaire was sent to practising gynaecologists (n= 1320) in Sweden. MAIN OUTCOME MEASURES: Attitudes to and personal use of HRT. RESULTS: The response rate was 76% in 2003 when 11% of the gynaecologists thought that all women without contraindications should be offered HRT compared with 44% in 1996 and 89% found it difficult to evaluate pros and cons with HRT in a clinical situation (74% in 1996). More gynaecologists in 2003 believed that HRT increased the risk for breast cancer (95% vs 71%). Twenty-five percent in 2003 stated that risk factors for osteoporosis were absolute indications for HRT (60% in 1996). Current ischaemic heart disease was considered to be an indication for HRT by 7% in 2003 (60% in 1996). In 2003, current use of HRT was reported by 71% of female menopausal gynaecologists (88% in 1996). CONCLUSIONS: Swedish gynaecologists were more cautious in their management strategies concerning HRT in 2003 compared with 1996, probably influenced by results from the Heart and Estrogen/Progestin Replacement Study (HERS) and Women's Health Initiative (WHI) studies. Current use of HRT was still high among female gynaecologists, although it had decreased since 1996. 相似文献
63.
The aim of this study was to establish whether analysis of the left ventricular pressure waveform provides indicative information about cardiac load and contractility and to develop an algorithm for computer-based assessment of changes in these variables. In eight healthy standard breed anaesthetized open-chest pigs, a high frequency response guide-wire mounted pressure sensor was introduced into the left ventricle. Preload reduction was induced by vena cava occlusion, afterload increase by an i.v. injection of phenylephrine and increased contractility by an i.v. injection of adrenalin. Left ventricular pressure waveform analysis was performed by plotting the slope of the pressure curve during the systolic ejection period versus maximal systolic pressure. The analysis revealed characteristic changes in left ventricular pressure and pressure waveform and identified easily discernible reaction patterns in the slope versus maximal pressure plot, specific for each provocation. Analysis of the left ventricular waveform provides indicative information about loading conditions and contractility. The proposed algorithm can easily be implemented in pressure monitoring systems allowing real-time assessment and discrimination of acute changes in preload, afterload and myocardial performance. 相似文献
64.
Osteoporosis in adults with meningomyelocele: an unrecognized problem at rehabilitation clinics 总被引:3,自引:0,他引:3
Valtonen KM Goksör LA Jonsson O Mellström D Alaranta HT Viikari-Juntura ER 《Archives of physical medicine and rehabilitation》2006,87(3):376-382
OBJECTIVES: To assess the prevalence of osteoporosis and osteopenia in adults with meningomyelocele and to explore whether neurologic level, ambulatory status, and other medical problems are associated with bone mineral density (BMD). DESIGN: A cross-sectional study, including a self-administered questionnaire and clinical assessment. SETTING: Outpatient referral clinic in Sweden. PARTICIPANTS: Twenty-one adults (mean age, 30 y) with meningomyelocele admitted to the Young Adult Teams in G?teborg and Boras, Sweden. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: BMD in the lumbar spine and hip and forearm measured with dual x-ray absorptiometry. RESULTS: Seven (33%) subjects had osteoporosis in at least 1 of the measured sites. Three patients had osteopenia and 2 had osteoporosis in the lumbar spine. Among the 15 subjects whose BMD of the hip region could be reliably measured, 7 (47%) had osteoporosis in the femoral neck or trochanteric region of the hip. Subjects with other medical problems commonly occurring in meningomyelocele had lower BMD in the femoral neck and trochanteric region of the hip than subjects without such factors. Ambulation alone showed only a tendency to be associated with BMD of the femoral neck, whereas the effect of other medical risk factors on BMD of the femoral neck was stronger among the nonambulators than the ambulators. CONCLUSIONS: Our results show that osteoporosis is a medical problem to be considered when treating and rehabilitating patients with meningomyelocele. 相似文献
65.
66.
Valzania C Gadler F Winter R Braunschweig F Brodin LA Gudmundsson P Boriani G Eriksson MJ 《European journal of heart failure》2008,10(5):514-520
BACKGROUND: Relatively limited and conflicting data are available on the effects of cardiac resynchronization therapy (CRT) on coronary blood flow (CBF). AIMS: To investigate changes in the left anterior descending coronary artery (LAD) flow under different CRT pacing modes by means of transthoracic Doppler echocardiography (TTE). METHODS: Twenty-two responders to CRT (67+/-11 years) with idiopathic dilated cardiomyopathy underwent TTE assessment of LAD flow and Tissue Velocity Imaging during 4 programming modes: intrinsic conduction (IC), right ventricular pacing (RV), simultaneous biventricular pacing (BVP), BVP with left ventricular (LV) pre-activation. RESULTS: Mean coronary flow velocity (CFV) was increased by simultaneous BVP (p=0.0063 vs. IC) and BVP with LV pre-activation (p<0.0001 vs. IC; p=0.027 vs. simultaneous BVP). Peak CFV and LAD flow velocity/time integral were highest during BVP with LV pre-activation. A reduction in septal-to-lateral delay and an increase in peak systolic velocity in the basal septum were observed during simultaneous BVP and BVP with LV pre-activation. CONCLUSIONS: In CRT responders with idiopathic dilated cardiomyopathy, an increase in LAD flow, assessed by TTE, was observed during simultaneous BVP and BVP with LV pre-activation. This was associated with an improvement in regional myocardial contraction and a decrease in intraventricular dyssynchrony. 相似文献
67.
Two osteosarcoma cell lines, one fibrosarcoma and one undifferentiated mesenchymal tumour obtained at operation, all of human origin, were transplanted in serial passages in athymic nude mice. The growth rate was analysed and the morphologic appearance compared both with the original tumours and after each passage. All tumours retained their morphologic characteristics during the transplantation and passaging in the nude mice with only minor alterations in structure. The growth rates of the tumours showed great variability even in the same passage of each tumour, although the growth rates became somewhat more regular and predictable after some passages. 相似文献
68.
Brostrom R Fred D Heetderks A Desai M Song R Haddad M Wada R Bamrah S 《American journal of public health》2011,101(1):14-18
A single case of multidrug-resistant tuberculosis (MDR-TB) can overwhelm the technical and financial capacity of small TB programs. In May 2008, the island state of Chuuk requested assistance for their first cases of MDR-TB. Second-line drugs and isolation rooms were unavailable, lab capacity was limited, and clinicians lacked experience. Delayed response caused prolonged transmission among household contacts. Several agencies responded with technical assistance and resources. Subsequent evaluations identified 16 additional MDR-TB cases and 124 infected contacts. Within six months, the local TB program gained remarkable capacity to manage MDR-TB cases and contacts, and greatly improve care for all TB patients. The Chuuk outbreak demonstrates the importance of establishing MDR-TB readiness in smaller jurisdictions and maintaining an essential TB control infrastructure. 相似文献
69.
Effect of angular error on tissue Doppler velocities and strain 总被引:1,自引:0,他引:1
One of the major criticisms of ultrasound Doppler is its angle dependency, that is its ability to measure velocity components directly to or from the transducer only. The present article aims to investigate the impact of this angular error in a clinical setting. Apical two- and four-chamber views were recorded in 43 individuals, and the myocardium was marked by hand in each image. We assume that the main direction of the myocardial velocities is longitudinal and correct for the angular error by backprojecting measured velocities onto the longitudinal direction drawn. Strain was calculated from both corrected and uncorrected velocities in 12 segments for each individual. The results indicate that the difference between strain values calculated from corrected and uncorrected velocities is insignificant in 5 segments and within a decimal range in 11 segments. The biggest difference between measured and corrected strain values was found in the apical segments. Strain is also found to be more robust against angular error than velocities because the difference between corrected and uncorrected values is smaller for strain. Considering that there are multiple sources of noise in ultrasound Doppler measurements, the authors conclude that the angular error has so little impact on longitudinal strain that correction for this error can safely be omitted. (ECHOCARDIOGRAPHY, Volume 20, October 2003) 相似文献
70.
Regulation of Ca2+-dependent cyclic AMP accumulation and Ca2+ metabolism in intact pituitary tumor cells by modulators of prolactin production 总被引:5,自引:0,他引:5
The responsiveness of anterior pituitary tumor (GH3) cells to promoters of prolactin secretion and/or synthesis and cyclic AMP accumulation was studied as a function of cellular Ca2+ content. GH3 cells exposed to media containing 1 mM ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid were reduced 7-fold in Ca2+ content without loss of viability. Preparations of Ca2+-depleted cells were largely unchanged in cyclic AMP content when challenged by thyrotropin-releasing hormone (TRH), whereas cells which were subsequently restored at optimal Ca2+ (0.5 mM) responded to the hormone with 2- to 3-fold increases in cyclic AMP content. The decreased responsiveness of Ca2+-depleted cells to TRH was not influenced by phosphodiesterase inhibitors, incubation time, or hormone concentration. TRH-dependent cyclic AMP accumulation was markedly potentiated by forskolin in Ca2+-restored, but not in Ca2+-depleted, cell preparations. Forskolin extended the time period during which cyclic AMP accumulated in response to TRH without altering the TRH concentration dependency of the cells. Varying increases in GH3 cyclic AMP content occurred in response to other hormones or agents which enhance prolactin secretion and/or synthesis. In Ca2+-restored cells, cyclic AMP content was increased 2-fold by prostaglandin E1 (PGE1) and epidermal growth factor (EGF), 10- to 15-fold by vasoactive intestinal polypeptide (VIP) and 6-fold by phorbol myristate acetate (PMA); the capacity of Ca2+-depleted cells, however, to accumulate cyclic AMP in response to PGE1, EGF, and VIP was greatly reduced. Accumulation of cyclic AMP following short-term incubations with cholera toxin similarly was dependent on Ca2+. Exposure of GH3 cells preloaded with 45Ca to TRH, PGE1, EGF, PMA, or VIP resulted in losses of cell-associated 45Ca. Pretreatment with these agents resulted in a decreased capacity of the cells to accumulate 45Ca from the extracellular medium. The results of this study support the hypothesis that various putative humoral regulators of prolactin secretion and/or synthesis act on GH3 cells to alter intracellular Ca2+ metabolism which in turn results in an increased cyclic AMP content through stimulation of adenylate cyclase activity. 相似文献