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991.
This study tested whether parent and child affective attitudes and interactional behavior co-varied with the presence or absence of associated aggressive symptomatology in families with an attention deficit hyperactivity disorder (ADHD) child. Affective attitudes of both parents and their ADHD sons were studied using a modified measure of expressed emotion, the five minute speech sample (FMSS-EE), in 29 families. A direct interaction task was also used to measure verbal and non-verbal communication. FMSS-EE status predicted parental interactional behavior, but the degree of child aggressiveness did not. The child's behavior towards parents, however, was highly correlated with their aggressiveness but not their EE status regarding their parents, despite the fact that child and parent EE were highly correlated. The study supports the notion that aggressiveness and a negative family climate may be independent factors in determining the long-term course of ADHD children.  相似文献   
992.
Objectives  To measure the accuracy and quality of immunization information systems in a range of low-income countries eligible to receive GAVI support.
Methods  The Data Quality Audit (DQA) uses a WHO validated, standard methodology to compare data collected from health unit (HU) records of immunizations administered with reports of immunizations at central level and to collect quality indicators of the reporting system. The verification factor (VF), as a measure of accuracy, expresses the proportion of immunizations reported at national level that can be tracked down to the HU. A VF of 80% or above entitles countries to receive additional GAVI financial support. Quality indicators are assigned points which were summed to obtain quality scores (QS) at national, district and HU levels. DQAs included here were conducted between 2002 and 2005 in 41 countries, encompassing 1082 primary healthcare units in 188 randomly selected districts.
Results  Almost half of countries obtained a VF below 80% and only nine showed consistently high VF and QS scores. The most frequent weaknesses in the information systems were inconsistency of denominators used to estimate coverage, poor availability of guidelines (e.g. for late reporting), incorrect estimations of vaccine wastage and lack of feedback on immunization performance. In all six countries that failed a first DQA and undertook a second DQA, the VF and all QSs improved, not all of them statistically significantly.
Conclusions  The DQA is a diagnostic tool to reveal a number of crucial problems that affect the quality of immunization data in all tiers of the health system. It identifies good performance at HU and district levels which can be used as examples of best practices. The DQA methodology brings data quality issues to the top of the agenda to improve the monitoring of immunization coverage.  相似文献   
993.
Anchorage and growth factor independence are cardinal features of the transformed phenotype. Although it is logical that the two pathways must be coregulated in normal tissues to maintain homeostasis, this has not been demonstrated directly. We showed previously that down-modulation of β1-integrin signaling reverted the malignant behavior of a human breast tumor cell line (T4–2) derived from phenotypically normal cells (HMT-3522) and led to growth arrest in a three-dimensional (3D) basement membrane assay in which the cells formed tissue-like acini (14). Here, we show that there is a bidirectional cross-modulation of β1-integrin and epidermal growth factor receptor (EGFR) signaling via the mitogen-activated protein kinase (MAPK) pathway. The reciprocal modulation does not occur in monolayer (2D) cultures. Antibody-mediated inhibition of either of these receptors in the tumor cells, or inhibition of MAPK kinase, induced a concomitant down-regulation of both receptors, followed by growth-arrest and restoration of normal breast tissue morphogenesis. Cross-modulation and tissue morphogenesis were associated with attenuation of EGF-induced transient MAPK activation. To specifically test EGFR and β1-integrin interdependency, EGFR was overexpressed in nonmalignant cells, leading to disruption of morphogenesis and a compensatory up-regulation of β1-integrin expression, again only in 3D. Our results indicate that when breast cells are spatially organized as a result of contact with basement membrane, the signaling pathways become coupled and bidirectional. They further explain why breast cells fail to differentiate in monolayer cultures in which these events are mostly uncoupled. Moreover, in a subset of tumor cells in which these pathways are misregulated but functional, the cells could be “normalized” by manipulating either pathway.  相似文献   
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996.
OBJECTIVE: To investigate the occurrence of benign paroxysmal positional nystagmus in subjects undergoing treatment with potentially ototoxic medications. STUDY DESIGN: Prospective and retrospective record reviews. SETTING: Tertiary referral neurotology clinic; clinical research and technology center. SUBJECTS: Ninety-nine hospitalized subjects undergoing treatment of infectious disease or carcinoma with potentially ototoxic medications. INTERVENTIONS: Records review, tests of vestibular function. MAIN OUTCOME MEASURE: Results of Hallpike positional tests for benign paroxysmal positional nystagmus (electro-oculography). RESULTS: Forty-one (41%) of 99 subjects were female and 58 (59%) were male. Age range was 15 to 73 years (mean, 47 years). Forty-nine (50%) of 99 subjects had an unequivocally positive Hallpike test for benign paroxysmal positional nystagmus in one or both ears. The occurrence of benign paroxysmal positional nystagmus in the Hallpike-positive population was distributed equally across age decades. Of the 49 subjects with benign paroxysmal positional nystagmus, 22 (44%) were female and 27 (56%) were male. CONCLUSIONS: Benign paroxysmal positional nystagmus is the most common cause of vertigo in the general population, including subjects receiving ototoxic drugs. Complaints of vertigo in subjects receiving ototoxic drugs therefore may or may not indicate onset of ototoxicity. Occurrence of benign paroxysmal positional nystagmus in subjects receiving ototoxic drugs was independent of gender or age. The high occurrence rate of benign paroxysmal positional nystagmus in subjects receiving potentially ototoxic medications is consistent with the observation that benign paroxysmal positional nystagmus occurs in combination with many pathologic conditions. Benign paroxysmal positional nystagmus presenting in subjects receiving ototoxic drugs may complicate the clinical identification of ototoxicity and obfuscate clinical decision-making processes.  相似文献   
997.
We report a new association between interictal myoclonus and paroxysmal kinesigenic dyskinesia (PKD) in 2 patients. By definition, PKD is transient, but the overexcitability of the neuronal system that induces these attacks may be permanent. Interictal myoclonus could be a manifestation of permanent overexcitability.  相似文献   
998.

Background  

Despite evidence of the benefits of exercise in cancer survivors, exercise participation rates tend to decline after treatments. Few studies have examined the determinants of exercise in less common cancer sites. In this study, we examined medical, demographic, and social cognitive correlates of exercise in endometrial cancer survivors using the Theory of Planned Behavior (TPB).  相似文献   
999.
Mammographic features are associated with breast cancer risk, but estimates of the strength of the association vary markedly between studies, and it is uncertain whether the association is modified by other risk factors. We conducted a systematic review and meta-analysis of publications on mammographic patterns in relation to breast cancer risk. Random effects models were used to combine study-specific relative risks. Aggregate data for > 14,000 cases and 226,000 noncases from 42 studies were included. Associations were consistent in studies conducted in the general population but were highly heterogeneous in symptomatic populations. They were much stronger for percentage density than for Wolfe grade or Breast Imaging Reporting and Data System classification and were 20% to 30% stronger in studies of incident than of prevalent cancer. No differences were observed by age/menopausal status at mammography or by ethnicity. For percentage density measured using prediagnostic mammograms, combined relative risks of incident breast cancer in the general population were 1.79 (95% confidence interval, 1.48-2.16), 2.11 (1.70-2.63), 2.92 (2.49-3.42), and 4.64 (3.64-5.91) for categories 5% to 24%, 25% to 49%, 50% to 74%, and > or = 75% relative to < 5%. This association remained strong after excluding cancers diagnosed in the first-year postmammography. This review explains some of the heterogeneity in associations of breast density with breast cancer risk and shows that, in well-conducted studies, this is one of the strongest risk factors for breast cancer. It also refutes the suggestion that the association is an artifact of masking bias or that it is only present in a restricted age range.  相似文献   
1000.
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