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81.
82.
BACKGROUND: An echocardiographic assessment of left ventricular (LV) diastolic dysfunction is still challenging when identifying a pseudonormal mitral pattern (PSE) in an unselected population. The present study analyzed and compared the accuracy of various parameters in correctly identifying a PSE pattern in patients with a broad range of ejection fraction (EF) and degree of mitral regurgitation. METHODS: Eighty-two patients with E/A > or = 1 and an invasive determination of left ventricular end-diastolic pressure (LVEDP) were enrolled in the study. Mitral E wave (E(max)) and A (A(max)) velocities, E (DTe) and A (DTa) deceleration times, pulmonary vein systolic and diastolic velocities, and time velocity integrals were measured. The different duration between mitral and pulmonary vein A wave (A'-A) also was calculated. E(max) and E/A during Valsalva maneuver were measured and expressed as percentage compared with baseline. LV end-diastolic (LVD), end-systolic (LVS), and EF were measured from the apical four-chambers view (area-length method). Left atrial end-systolic (LA(max)) and end-diastolic (LA(min)) were measured from the apical four- and two-chambers views (area-length method). Left atrial filling volume (LA(fill)) was the difference between LA(max) and LA(min). Mitral regurgitant volume was estimated by the following equation: MR(vol) = 6.18 + (1.01 * LA(fill)) - (0.783 * PVs %). RESULTS: Thirty-two patients (age: 55 +/- 21 years; 75% male) had LVEDP < or = 18 mmHg and were classified as normal mitral pattern (Group 1). Fifty patients (age: 57 +/- 22 years; 76% male) had LVEDP > 18 mmHg, and were classified accordingly as having PSE (Group 2). At logistic univariate analysis, DTa (0.005), LV EF (0.01), A'-A (< 0.0001) and % E/A (0.03) were the more powerful predictors of PSE. A'-A had the highest global accuracy in identifying PSE in patients with reduced (90%) and normal (88%) LV EF. CONCLUSION: A'-A has the highest accuracy in identifying PSE in an unselected population. This parameters should be implemented in routine echocardiography since it allows additional information about LV diastolic function assessment.  相似文献   
83.

Introduction

Breast cancer is the most prevalent cancer in women, with slightly more than ten percent developing the disease in Western countries. Mammography screening is a well established method to detect breast cancer.

Aims

The aim of the position statement is to review critically the advantages and shortcomings of population based mammography screening.

Materials and methods

Literature review and consensus of expert opinion.

Results and conclusion

Mammography screening programmes vary worldwide. Thus there are differences in the age at which screening is started and stopped and in the screening interval. Furthermore differences in screening quality (such as equipment, technique, resolution, single or double reading, recall rates) result in a sensitivity varying from 70% to 94% between studies. Reporting results of screening is subject to different types of bias such as overdiagnosis. Thus because of the limitations of population-based mammography screening programmes an algorithm for individualized screening is proposed.  相似文献   
84.
Objectives. We evaluated the efficacy of a primary care intervention targeting pregnant African American women and focusing on psychosocial and behavioral risk factors for poor reproductive outcomes (cigarette smoking, secondhand smoke exposure, depression, and intimate partner violence).Methods. Pregnant African American women (N = 1044) were randomized to an intervention or usual care group. Clinic-based, individually tailored counseling sessions were adapted from evidence-based interventions. Follow-up data were obtained for 850 women. Multiple imputation methodology was used to estimate missing data. Outcome measures were number of risks at baseline, first follow-up, and second follow-up and within-person changes in risk from baseline to the second follow-up.Results. Number of risks did not differ between the intervention and usual care groups at baseline, the second trimester, or the third trimester. Women in the intervention group more frequently resolved some or all of their risks than did women in the usual care group (odds ratio = 1.61; 95% confidence interval = 1.08, 2.39; P = .021).Conclusions. In comparison with usual care, a clinic-based behavioral intervention significantly reduced psychosocial and behavioral pregnancy risk factors among high-risk African American women receiving prenatal care.Adverse pregnancy outcomes are particularly common among women who are members of racial/ethnic minority groups.14 African American infants are 3.4 times more likely than are White infants to die in the neonatal period, a disadvantage that persists even when mothers have appropriately early and equal access to prenatal care.5 In Washington, DC, death rates among non-Hispanic African American infants remain unacceptably high (17.0 per 1000 live births in 2005) despite an overall decline in infant mortality from 18.6 per 1000 live births in 1992 to 14.0 per 1000 births in 2005.6 Psychosocial and behavioral risks are recognized as potential contributors to poor reproductive outcomes.79 Poverty,10 limited social support,11 smoking,12 illicit drug use,13 depression,14 anxiety,14,15 and intimate partner violence (IPV)16,17 are all associated to varying degrees with pregnancy complications, premature and low-birthweight deliveries, stillbirths, and infant mortality.There is increasing recognition of the role of primary care in screening, diagnosis, and treatment of behavioral, mental health, and psychosocial concerns,1827 because of the significant association between medical morbidity and behavioral and mental health problems.28 Although interventions involving primary care providers may have limited success, they can be cost-effective.18,24 Because access to and use of behavioral and mental health care remain problematic, especially among members of underserved minority groups,2932 making such care available through primary care services may avert missed opportunities.Prenatal care may be a venue to address behavioral and mental health issues that can potentially affect the health of pregnant women and their unborn children.33 The guidelines of the American College of Obstetrics and Gynecology and the American Academy of Pediatrics34,35 suggest ways primary care providers can screen for behavioral and psychosocial risk factors. Despite these guidelines, many providers still fail to screen pregnant women,3538 with screening rates varying according to type of provider,36,39 risk factors,36 population group,40 and provider risk perceptions.41 Furthermore, when implemented, psychosocial and behavioral interventions have been only moderately successful.42,43Such inconsistent results may arise from multiple factors, including differences in study design, participant engagement, and intervention content or implementation, including approaches that address only 1 of multiple, co-occurring psychosocial or behavioral risk factors. Behavioral and psychosocial factors associated with poor pregnancy outcomes are related to and serve as risk factors for one another44; therefore, an alternative approach would be to provide an intervention simultaneously addressing multiple psychosocial and behavioral risk factors among pregnant women, as has been done in relation to other health risks.4547A recent study focusing on 3569 Medicaid-eligible pregnant women examined the effects of the Prenatal Plus Program in Colorado with respect to smoking, inadequate prenatal weight gain, and “psychosocial problems” (defined as “significant or severe stress as a result of personal or family safety needs, lack of support systems, or an inability to meet basic needs”).48(p1955) Women who had at least 10 Prenatal Plus visits were more likely than were women who did not to reduce these risks; in addition, only 7.0% of women who resolved all of their risks delivered low-birthweight infants, whereas 13.2% of those who resolved none of their risks did so. In spite of these promising results, the nonexperimental nature of the Colorado study may have created unquantifiable biases favoring the intervention.Moreover, only 4% of all births in Colorado, and 7% of Prenatal Plus deliveries, occurred among African American women, the group at greatest risk of adverse pregnancy outcomes. Thus, further experimental investigations in which rigorous randomized trial designs are used to assess vulnerable African American women are needed to better appreciate the potential merits of an integrated intervention focusing on psychosocial and behavioral risk factors during pregnancy.We conducted a randomized clinical trial testing the efficacy of an integrated intervention targeting multiple behavioral and psychosocial risk factors among pregnant African American women in the District of Columbia. The risk factors we chose to address were cigarette smoking, secondhand smoke exposure, depression, and IPV.  相似文献   
85.
In a prospective study of the quantitative bone changes induced by B-cell cancers other than multiple myeloma (MM), but including chronic lymphocytic leukemia (CLL; n = 8), hairy cell leukemia (HCL; n = 3), and Waldenstr?m disease (WD; n = 7), an abnormal bone remodeling close to malignant cells was found in 80% of the patients. This was observed more frequently in cases of diffuse, but not nodular, bone marrow involvement by tumor cells. More particularly, excessive bone resorption (a major feature of MM) associated with a normal to low bone formation (i.e., uncoupling bone disease) was the most frequent feature and in the same range of that observed in overt MM. However, as opposed to MM, this bone resorption was characteristically mediated by small mononucleated osteoclasts (i.e., microresorption). The same phenomena of abnormal bone remodeling, the uncoupling process, excessive bone resorption, and above all microresorption were confirmed by the detailed bone study of five cases of B-cell cancers other than MM presenting lytic bone lesions and hypercalcemia. The current findings are important for clarifying the biology of these B-cell malignant diseases, and also could be of diagnostic and prognostic value.  相似文献   
86.
87.
The association between posterior fossa malformations and epilepsy is rarely reported in the literature. We describe 54 cases with posterior fossa malformations, according to embryogenesis classification, divided into two groups on the basis of presence or absence of epilepsy. Epilepsy occurred in 22 cases (40.7%) and was not related to the type of posterior fossa malformation or to supratentorial cerebral lesions associated with the malformation. Familial antecedents for epilepsy and/or febrile convulsions influenced the presence of epilepsy in patients with posterior fossa malformations (P < .01). Epilepsy was mainly partial (77.3%); benign partial/generalized epilepsies and febrile convulsions occurred in 27.3% of cases. Seizures disappeared for 2 or more years at the end of follow-up in 36.4% of patients. Good epilepsy prognosis was not related to the age at onset of seizures, familial antecedents for epilepsy and/or febrile convulsions, supratentorial associated lesions, or age of patients at the last observation. Profound mental retardation prevailed in patients with epilepsy (P < .01), as did pathologic electroencephalograms (EEG) (P < .0001), with paroxysmal abnormalities (P < .001) and asymmetry (P < .01). In our 54 cases of posterior fossa malformation, we identified two risk factors for epilepsy: familial antecedents for epilepsy and/or febrile convulsions and the involvement of the cerebellum in the malformation.  相似文献   
88.
We examine the role of visual feedback in the programming and execution of reaching movement in patients with Parkinson's disease without cognitive impairment and patients with Alzheimer's disease without extrapyramidal signs. Controls were normally aging subjects. All subjects moved a cursor to targets on a digitizing tablet without seeing their limb. Starting and target positions were always visible on a screen while, during movement, cursor position was either visible or blanked. They were instructed to make uncorrected movements, as fast and as accurate as possible without minimizing reaction time. In absence of visual feedback, movement accuracy in patients with AD was severely impaired. Hand paths of parkinsonian patients were as accurate as normal subjects' with similar temporal velocity profiles and movement speed. With cursor feedback, accuracy was the same in the three groups, although movement speed and transport phase in patients with Alzheimer's disease were significantly reduced compared to the other groups. Also, movements of parkinsonian patients showed shorter transport phase and lower mean velocity than controls'. The different characteristics of the motor performance suggests that in the two diseases visual information is used differently for both motor programming and execution: patients with Alzheimer's disease, while scarcely using feed forward commands, relied on continuous on-line external cues. The correlation of motor performance with cognitive impairment argues against the hypothesis of basal ganglia involvement in AD. The motor abnormalities we found may represent early subclinical manifestation of apraxic disturbance. Parkinsonian patients showed higher reliance on feedback commands only with cursor feedback: this could be explained by their difficulty in engaging effectively automatic routines when distractors are present.  相似文献   
89.
90.
Abnormal growth hormone (GH) and adrenocorticotropic hormone (ACTH)/cortisol secretory patterns in response to a glucose load have been observed in underweight anorectic women. The present study was performed in an attempt to establish whether changes in the hypothalamic/pituitary sensitivity to hyperglycemia occur in bulimia in the absence of weight disturbance. Therefore, serum GH, plasma cortisol, and plasma insulin concentrations were measured in eight women with normal weight bulimia and in eight normal women during an intravenous glucose (0.33 g/kg as an bolus) tolerance test (IGTT). In addition, since abnormal pituitary hormone responses to a glucose load might reflect alterations in somatostatin (SRIH) release, TSH secretion also was measured, in view of its sensitivity to SRIH inhibition.

Both GH and cortisol levels progressively and significantly declined during IGTT in the normal subjects. In the bulimic women, cortisol levels remained unchanged, whereas GH concentrations rose significantly after glucose injection. Plasma cortisol and serum GH levels were significantly higher in the bulimic than in the control subjects. No significant differences between groups were observed in hyperglycemia-induced insulin increments or in TSH decrements.

These data indicate that an altered sensitivity to hyperglycemia affects the hypothalamic/pituitary centers controlling the secretion of the counterregulatory hormones GH and ACTH/cortisol in bulimia nervosa. The lack of a simultaneous change in the TSH secretory pattern argues against a possible involvement of SRIH in the pathophysiology of this disorder.  相似文献   

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