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41.
The International Study of Asthma and Allergies in Childhood (ISAAC) Phase One showed large worldwide variations in the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema, up to 10 to 20 fold between countries. Ecological analyses were undertaken with ISAAC Phase One data to explore factors that may have contributed to these variations, and are summarised and reviewed here.In ISAAC Phase One the prevalence of symptoms in the past 12 months of asthma, rhinoconjunctivitis and eczema were estimated from studies in 463,801 children aged 13 - 14 years in 155 centres in 56 countries, and in 257,800 children aged 6-7 years in 91 centres in 38 countries. Ecological analyses were undertaken between symptom prevalence and the following: Gross National Product per capita (GNP), food intake, immunisation rates, tuberculosis notifications, climatic factors, tobacco consumption, pollen, antibiotic sales, paracetamol sales, and outdoor air pollution.Symptom prevalence of all three conditions was positively associated with GNP, trans fatty acids, paracetamol, and women smoking, and inversely associated with food of plant origin, pollen, immunisations, tuberculosis notifications, air pollution, and men smoking. The magnitude of these associations was small, but consistent in direction between conditions. There were mixed associations of climate and antibiotic sales with symptom prevalence.The potential causality of these associations warrant further investigation. Factors which prevent the development of these conditions, or where there is an absence of a positive correlation at a population level may be as important from the policy viewpoint as a focus on the positive risk factors. Interventions based on small associations may have the potential for a large public health benefit.  相似文献   
42.
We investigated whether nuclear factor kappa B (NF‐κB), which exhibits a regulated pattern of activity during murine mammary gland development, plays an important role during lactation and involution, when milk production ceases and the gland undergoes apoptosis and re‐modeling. We generated a doxycycline inducible transgenic mouse model to activate NF‐κB specifically in the mammary epithelium through expression of a constitutively active form of IKK2, the upstream kinase in the classical NF‐κB signaling cascade. We found that activation of NF‐κB during involution resulted in a more rapid reduction in milk levels and increased cleavage of caspase‐3, an indicator of apoptosis. We also found that activation of NF‐κB during lactation with no additional involution signals had a similar effect. The observation that NF‐κB is a key regulator of milk production led us to investigate the role of NF‐κB during mastitis, an infection of the mammary gland in which milk loss is observed. Mammary gland injection of E. coli LPS resulted in activation of NF‐κB and milk loss during lactation. This milk loss was decreased by selective inhibition of NF‐κB in mammary epithelium. Together, our data reveal that activation of NF‐κB leads to milk clearance in the lactating mammary gland. Therefore, targeting of NF‐κB signaling may prove therapeutic during mastitis in humans and could be beneficial for the dairy industry, where such infections have a major economic impact. J. Cell. Physiol. 222:73–81, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
43.
Sherrill JM  Kyte J 《Biochemistry》1999,38(10):3106-3111
The addition of epidermal growth factor (EGF) to epidermal growth factor receptor (EGF receptor) dissolved in a solution of the detergent Triton X-100 results in the activation of its protein tyrosine kinase. To investigate the importance of the sites for self-phosphorylation on the enzyme in this process, the kinetics of activation of a deletion mutant missing the last 195 amino acids of the protein, including all of the sites for self-phosphorylation, were followed by monitoring the initial velocity at which the enzyme catalyzes the phosphorylation of the exogenous substrate RRKGSTAENAEYLRV. The activation of the enzymatic activity of this deletion mutant of EGF receptor displays kinetics that are second-order with respect to the concentration of the enzyme as does wild-type EGF receptor. The second-order rate constant for its activation is 36 +/- 10 microM-1 min-1, which is only 3-fold greater than the second-order rate constant for the activation of wild-type EGF receptor under the same conditions (13 +/- 2 microM-1 min-1). These results suggest that the mechanism by which the protein tyrosine kinase of the deletion mutant is activated is the same as that for the activation of the wild-type receptor and that the sites of self-phosphorylation in the wild-type EGF receptor do not participate in the mechanism of activation of the enzyme.  相似文献   
44.
-Lactam antibiotic susceptibility and the presence of -lactamase were examined in clinical strains ofBacteroides species. All strains produced a noninducible, cell-associated cephalosporinase. Based on isoelectric focusing, molecular weight determinations, substrate profiles, and inhibition studies, it was concluded that allBacteroides strains examined produced a very similar, if not identical, -lactamase in terms of these enzymatic and physical characteristics.  相似文献   
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A simple two-step synthesis method was used to make 51 B-ring-substituted 4-hydroxyquinolines allowing analysis of the effect of ring substitutions on inhibition of growth of chloroquine sensitive and resistant strains of Plasmodium falciparum, the dominant cause of malaria morbidity. Substituted quinoline rings other than the 7-chloroquinoline ring found in chloroquine were found to have significant activity against the drug-resistant strain of P. falciparum W2.  相似文献   
48.
Optimization of pyrrolidinone based HIV protease inhibitors   总被引:1,自引:0,他引:1  
Optimization of P1-substituted pyrrolidinone based HIV protease inhibitors has yielded analogs with very potent antiviral activity.  相似文献   
49.
Several approaches have been suggested for estimating a respiratory response slope when both x and y variables are observed with error. Recently, a maximum likelihood estimate under the assumption of a bivariate normal distribution has been proposed. A method of moments solution yields a slope estimate of y/x as long as the underlying process mean is nonzero. This paper extends the maximum likelihood approach to the case where the process mean is zero. In this case, certain additional error assumptions must be made to yield a unique estimate. These concepts are applied to the problem of estimating an effective lung volume for steady-state breath-to-breath gas exchange data during exercise.  相似文献   
50.

Background

People with dementia are susceptible to adverse drug reactions (ADRs). However, they are not always closely monitored for potential problems relating to their medicines: structured nurse-led ADR Profiles have the potential to address this care gap. We aimed to assess the number and nature of clinical problems identified and addressed and changes in prescribing following introduction of nurse-led medicines’ monitoring.

Design

Pragmatic cohort stepped-wedge cluster Randomised Controlled Trial (RCT) of structured nurse-led medicines’ monitoring versus usual care.

Setting

Five UK private sector care homes

Participants

41 service users, taking at least one antipsychotic, antidepressant or anti-epileptic medicine.

Intervention

Nurses completed the West Wales ADR (WWADR) Profile for Mental Health Medicines with each participant according to trial step.

Outcomes

Problems addressed and changes in medicines prescribed.

Data Collection and Analysis

Information was collected from participants’ notes before randomisation and after each of five monthly trial steps. The impact of the Profile on problems found, actions taken and reduction in mental health medicines was explored in multivariate analyses, accounting for data collection step and site.

Results

Five of 10 sites and 43 of 49 service users approached participated. Profile administration increased the number of problems addressed from a mean of 6.02 [SD 2.92] to 9.86 [4.48], effect size 3.84, 95% CI 2.57–4.11, P <0.001. For example, pain was more likely to be treated (adjusted Odds Ratio [aOR] 3.84, 1.78–8.30), and more patients attended dentists and opticians (aOR 52.76 [11.80–235.90] and 5.12 [1.45–18.03] respectively). Profile use was associated with reduction in mental health medicines (aOR 4.45, 1.15–17.22).

Conclusion

The WWADR Profile for Mental Health Medicines can improve the quality and safety of care, and warrants further investigation as a strategy to mitigate the known adverse effects of prescribed medicines.

Trial Registration

ISRCTN 48133332  相似文献   
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