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排序方式: 共有773条查询结果,搜索用时 15 毫秒
41.
Sorkin J Post W Pollin TI O'Connell JR Mitchell BD Shuldiner AR 《Mechanisms of ageing and development》2005,126(2):347-350
Lifespan is a complex phenotype determined by the interaction of genetic and environmental factors. This makes the identification of variants in genes that influence longevity challenging. We believe that the Old Order Amish (OOA) of Lancaster, Pennsylvania is an excellent population for studying the genetics of longevity. They are a closed population derived from a limited number of founders. They have large families and maintain extensive genealogic records dating to the 1700 s. They eschew modern technology; their lifestyle is little changed over the last 250 years. Homogeneity of environment and lifestyle factors across time and across the OOA population minimizes the influence that environmental factors have in determining the differences in lifespan between individuals. We hypothesize that this reduction in environmental variability will make it easier to identify the genetic factors that influence lifespan. In this article, we describe our strategy for identifying variants in genes that influence longevity in the Amish and present the results of our studies to date. 相似文献
42.
We describe a middle-aged Chinese systemic lupus erythematosus (SLE) patient developing steroid refractory and transfusion dependent red cell aplasia. Oral danazol 200 mg twice per day was started together with low-dose prednisolone therapy. There was no further recurrence of anemia 1 month after this combined therapy. 相似文献
43.
Dopamine (DA) and the DA transporter (DAT) play important roles in psychomotor stimulant behavioral activation and reward. By understanding how DAT activity is regulated, we will better appreciate its contribution to normal neurotransmission and to brain diseases like drug addiction. DAT is regulated long-term by chronic drug administration. It is also regulated in a rapid, dynamic fashion by many factors--including brief exposure to DAT substrates, e.g. DA and amphetamine, and inhibitors, e.g. cocaine. We found that individual differences in the initial and sensitized locomotor responsiveness of rats to cocaine reflect differences in in vivo DAT function. Our ex vivo studies have further suggested that differences in basal and/or rapid cocaine-induced expression of functional DATs in striatum contribute to the differences in initial responsiveness. Studies in model systems have demonstrated that short-term DAT regulation occurs by altered transporter trafficking, and thereby cell surface expression. For example, a rapid, complex regulation of DAT by DA is suggested. Amphetamine causes DAT internalization into early endosomal compartments whereas cocaine appears to up-regulate surface expression of DAT. Future studies are needed to confirm these observations in neurons, as well as to elucidate the mechanisms of rapid DAT endocytic trafficking at neuronal synapses. 相似文献
44.
Jin X Xia L Wang LS 《上海交通大学学报(医学版)》2007,27(11):1316-1316
Although cardiac hypertrophy in hypertension has been well recognized, the molecular mechanisms for the development of hypertrophy are still largely unknown. In this study, the protein expression profiles of left ventricular myocardia in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats at different ages were analyzed using 2-DE in combination with MALDI-TOF/TOF MS/MS. The results showed that 20 proteins were modulated in the hypertrophic myocardium. Out of these modulated proteins, 13 proteins presented significant changes in SHR at an early stage prior to the development of sustained hypertension, while the changes of the other 7 protein expres- sions occurred only at a late stage in SHR when the blood pressure was significantly elevated, and were largely reversible by treatment with rennin-angiotensin-aldosterone system inhibitors losartan or enalapril. These data demonstrate that the changes in energy metabolism in the hypertrophied heart favor an increase in glycolysis and a decrease in oxidation of fatty acid and glucose, which occur at an early stage in SHR without hypertension. Our results also provide evidence to support the hypothesis that oxidative stress plays an important role in the development of hypertensive cardiac hypertrophy. 相似文献
45.
Tumor rechallenge following primary tumor excision elicits systemic anti-inflammation that occurs rapidly, affects granulocytes as well as macrophages and is more severe, longer in duration, and induced by fewer tumor cells than the macrophage specific anti-inflammatory effect sometimes seen after primary tumor challenge. Factors important in the pathogenesis of this abnormality are the following. First, primary tumor excision was required as defects did not occur when a second tumor was transplanted during primary tumor growth. Second, the abnormality was restricted to neoplastic cells since normal cells were unable to substitute for either primary or secondary tumor challenge. Third, the anti-inflammatory effect was not due to surgical trauma or local irritation. Fourth, defective inflammation occurred in syngeneic but not allogeneic rats, suggesting an immunological basis for the anti-inflammation. Fifth, elevated glucocorticoids, such as might be expected from an immunological reaction or release of IL-1, may be a contributing but not sole cause for the phenomenon. 相似文献
46.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns. 相似文献
47.
Wendy Klein‐Schwartz John David Sorkin Suzanne Doyon 《Pharmacoepidemiology and drug safety》2010,19(8):819-824
Purpose
To assess the impact of a voluntary withdrawal of over‐the‐counter cough and cold medications (OTC CCMs) labeled for children under age 2 years on pediatric ingestions reported to the American Association of Poison Control Centers.Methods
Trend analysis of OTC CCMs ingestions in children under the age 6 years resulting from therapeutic errors or unintentional poisonings for 27 months before (pre‐) and 15 months after (post‐) the October 2007 voluntary withdrawal was conducted. The rates and outcome severity were examined.Results
The mean annual rate of therapeutic errors involving OTC CCMs post‐withdrawal, in children less than 2‐years of age, 45.2/100 000 (95%CI 30.7–66.6) was 54% of the rate pre‐withdrawal, 83.8/100 000 (95%CI 67.6–104.0). The decrease was statistically significant p < 0.02. In this age group, there was no difference in the frequency of severe outcomes resulting from therapeutic errors post‐withdrawal. There was no significant difference in unintentional poisoning rates post‐withdrawal 82.1/100 000 (66.0–102.2) vs. pre‐withdrawal 98.3/100 000 (84.4–114.3) (p < 0.21) in children less than 2‐years of age. There were no significant reductions in rates of therapeutic errors and unintentional poisonings in children ages 2–5 years, who were not targeted by the withdrawal.Conclusions
A significant decrease in annual rates of therapeutic errors in children under 2‐years reported to Poison Centers followed the voluntary withdrawal of OTC CCMs for children under age 2‐years. Concerns that withdrawal of pediatric medications would paradoxically increase poisonings from parents giving products intended for older age groups to young children are not supported. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献48.
The present study demonstrates many dynorphin (DYN)-immunoreactive fibers and presumed presynaptic terminals in rat lumbar ventral horn. The fibers and terminals seem to arise largely from DYN-containing intrinsic neurons in the dorsal horn. The majority of the presumed terminals closely surround a subpopulation of motoneurons that tend to be located in flexor motoneuron columns. Acute C fiber, but not A fiber, primary afferent stimulation depletes the ventral horn DYN immunostaining. We interpret these findings to indicate that the spinal DYN neurons are well positioned to serve both as modulators of nociceptive input and as interneurons in motor reflexes. We further hypothesize that the depletion of DYN-immunoreactivity that follows either acute C fiber stimulation or intense nociceptive stimuli may be the trigger for the upregulation in spinal cord DYN that occurs in models of chronic pain states. 相似文献
49.
Leuprorelin. A review of its pharmacology and therapeutic use in prostatic disorders. 总被引:1,自引:0,他引:1
Leuprorelin (leuprolide acetate) is a synthetic analogue of gonadotrophin-releasing hormone (GnRH) [luteinising hormone-releasing hormone (LHRH)] which initially stimulates luteinising hormone (LH) and hence testicular androgen release; continuous administration then results in profound suppression of these hormones. Testosterone levels associated with castration are attained within 3 to 4 weeks. A biodegradable subcutaneous or intramuscular depot formulation of leuprorelin 3.75 or 7.5 mg, which releases the drug at a constant rate over 28 days, is available and may be preferred over daily subcutaneous injections. The progression of previously untreated advanced prostatic cancer is delayed in 70 to 90% of men receiving leuprorelin, with median survival of approximately 2 years. The efficacy of leuprorelin is equivalent to that of estrogen therapy, but the tolerability of the GnRH analogue is far better. In contrast to most other studies of GnRH agonists, a slight survival advantage has been reported for combined treatment with leuprorelin and the antiandrogen flutamide. Small noncomparative trials reveal that leuprorelin also causes regression of benign hyperplastic prostate tissue with corresponding relief of obstructive, but not irritative, symptoms although continuous treatment is necessary to maintain remission. Impotence and flushing occur in most leuprorelin recipients but, unlike diethylstilbestrol (stilboestrol), cardiovascular toxicity and gynaecomastia are not significant problems. Symptom flare, usually manifested as bone pain in prostate cancer patients and exacerbation of obstructive symptoms in those with benign prostatic hypertrophy, can occur in 4 to 29% at the beginning of treatment. Leuprorelin treatment is therefore an established effective palliative measure in men with previously untreated advanced prostatic cancer, and may have a role in those with benign hypertrophy who are unfit for surgery. 相似文献
50.
Serotoninergic and noradrenergic projections to the ventral posterolateral nucleus of the monkey thalamus 总被引:1,自引:0,他引:1
K N Westlund L S Sorkin D G Ferrington S M Carlton H H Willcockson W D Willis 《The Journal of comparative neurology》1990,295(2):197-207
In the present study, serotoninergic and noradrenergic varicosities were identified in the ventral posterolateral nucleus of the macaque monkey. Monoaminergic neurons projecting to the ventral posterolateral nucleus of the thalamus were identified by using retrograde labeling with horseradish peroxidase combined with immunocytochemical staining for serotonin or dopamine-beta-hydroxylase. The midbrain nucleus raphe dorsalis was the major site of origin for neurons providing a serotoninergic projection to the ventral posterolateral nucleus. A few retrogradely labeled serotonin-containing neurons were also observed in the central superior and the raphe pontis nuclei. Noradrenergic cells with projections to the thalamus were primarily located in the nucleus locus coeruleus with some projection neurons in the nucleus subcoeruleus, and the A5 catecholamine cell group of the pons. 相似文献