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1.
R Nikolov J Maslarova I Semkova 《Methods and findings in experimental and clinical pharmacology》1992,14(8):577-583
The central effects of endothelin-1 (ET-1) and their modification by the calcium entry blocker cinnarizine have been investigated using CNS and hypoxia/ischemia tests. CNS tests comprised behavior, horizontal and vertical motor activity and hot plate test. Hypoxia/ischemia tests used were hypobaric hypoxia and complete ischemia by decapitation. ET-1 was injected intracerebroventricularly (i.c.v.) in a volume of 0.01 ml at doses of 1.25, 2.5 and 5 pmol/mouse 15 min before the tests. Cinnarizine (10 mg/kg, i.p.) was administered 60 min prior to ET-1. The i.c.v. ET-1 at all the doses used decreased horizontal and vertical motor activity and produced barrel-rolling. Survival/gasping time of mice subjected to hypoxia/ischemia increased dose-dependently. ET-1 showed an antinociceptive effect. Cinnarizine attenuated the appearance of barrel-rolling, did not antagonize disturbances in motor activity and reversed the antinociceptive effect of ET-1. In hypobaric hypoxia and decapitation cinnarizine antagonized the effects of 5 pmol/mouse ET-1 and potentiated that of 1.25 pmol/mouse. The pharmacological modification of the ET-1 effects by cinnarizine strongly suggests that the CNS actions of ET-1 might be due to multiple mechanisms triggered by an increased influx of extracellular Ca2+ into the brain cells. 相似文献
2.
From the leaves and flowers of Crataegus monogyna and C. Pentagyna six new flavonoid-C- and O-glycosides respectively have been isolated and identified as 2'-O-rhamnosyl-orientin, 2'-O-rhamnosyl-isoorientin, 2'-O-rhamnosyl-isovitexin, rutin, spiraeosid, 8-methoxy-k?mpferol and 8-methoxy-k?mpferol-3-O-glucoside. The structure of O-rhamnosyl-vitexin and O-acetyl-O-rhamnosyl-vitexin isolated previously, have been elucidated unambigiously mainly by NMR- and MS-spectroscopy. 相似文献
3.
Dharamainder Choudhary Ingela Jansson Ivaylo Stoilov Mansoor Sarfarazi John B Schenkman 《Drug metabolism and disposition》2004,32(8):840-847
The cytochrome P450 family 1 (CYP1) is considered to be one of the xenobiotic-metabolizing enzyme families and is responsible for oxidative metabolism of polycyclic aromatic hydrocarbons. For example, mouse Cyp1b1 was originally identified as the enzyme responsible for oxidative metabolism of 7,12-dimethylbenz(alpha)anthracene (DMBA). A comparison of the kinetics of this metabolism by mouse and human CYP1B1 orthologs revealed the mouse enzyme to have a more favorable metabolism of DMBA, with a catalytic efficiency ratio (CER) of 0.23. However, CYP1 enzymes are also capable of metabolism of endobiotics, and in the present study, the metabolism of retinoids and lipid endobiotics by human CYP1B1 and mouse Cyp1b1 orthologs was compared. Both hemoproteins oxidized retinol to retinal and retinal to retinoate, but did not oxidize retinoate. The CYP1B1 to Cyp1b1 CERs were 13 and 26 for the two steps, respectively; the Cyp1b1 K(m(app)) values for retinoids were 20-fold higher. Human family 1 cytochromes P450 had unique regional specificities for arachidonate oxidation: the major metabolites of CYP1A1, CYP1A2, and CYP1B1 were 75% terminal hydroxyeicosatetraenoic fatty acids (HETEs), 52% epoxyeicosatrienoic fatty acids (EETs), and 54% mid-chain HETEs, respectively. CYP1A1 and CYP1B1 K(m(app)) values for arachidonate were about 30 microM, whereas CYP1A2 K(m(app)) was 95 microM. The major metabolites of arachidonic acid by Cyp1b1 were EETs (50%) and midchain HETEs (37%). The mouse ortholog had a CER for metabolite production of 64 due to a K(m(app)) of 0.5 mM for arachidonate. 相似文献
4.
Dragan Deli Mira Goti Vladimir Otri Vesna Fridman Predrag Nikoli Ljiljana Jemuovi Vladimir Nikolov Sonja
erjav andor Groza 《Liver international》1993,13(6):302-304
ABSTRACT— In 614 HBsAg-positive Yugoslavian patients, radioimmunoassay testing for anti-delta showed the presence of this antibody in serum in 11.2%. Of the patients, 213 belonged to a risk group (i.v. drug users, hemophiliacs, hemodialysed patients and patients with posttransfusion hepatitis); a significant number of these patients (63; 29.6%) were found to have anti-delta. A second group was composed of 401 HBsAg-positive patients from the general population (patients with acute hepatitis B, with fulminant hepatitis B and patients with chronic HBV infection); delta infection was found only in six (1.5%). Immunohistochemical methods failed to demonstrate the delta antigen in the livers of 73 patients with chronic HBV infection. Testing the liver of 36 patients with fulminant hepatitis B for delta antigen demonstrated this reactivity in only one (2.8%) liver sample. Delta antigen was also found in the liver of a female patient who underwent biopsy in 1972. The results of this study suggest the HDV is not endemic in Yugoslavia; however, it is frequently found in patients at risk of blood exposure, primarily i.v. drug users. 相似文献
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The process of incorporating insulin pumps into the everyday lives of people with Type 1 diabetes: A critical interpretive synthesis 下载免费PDF全文
Claire Reidy MSc Mike Bracher PhD Claire Foster PhD Ivaylo Vassilev PhD Anne Rogers PhD 《Health expectations》2018,21(4):714-729
Background
Insulin pump therapy (IPT) is a technological advancement that has been developed to help people manage Type 1 diabetes (T1D). However, ways of managing diabetes requiring the implementation of health technologies bring new complexities and a need to understand the factors which enable people with T1D to incorporate a novel device. This new comprehension could provide an exemplar for people with long‐term conditions to incorporate new technologies more generally.Objective
To determine what influences the incorporation, adaptation and use of IPT into the everyday lives of people living with diabetes.Design
Critical interpretive synthesis (CIS) using systematic searches undertaken in 7 electronic databases of literature, published 2008 onwards.Results
A total of 4998 titles were identified, 274 abstracts reviewed, 39 full articles retrieved and 22 papers selected for analysis. Three themes emerged which were of relevance to the introduction and use of IPT; Tensions between expectations and experiences in adoption and early adaptation; Negotiation of responsibility and accessing support; Reflexivity, active experimentation and feedback.Conclusions
This CIS builds on earlier reviews on lived experiences of IPT. Novel insights are offered through examination of the experiences of pump users from children through to adults, their families and health‐care professionals. Expectations of what the device can do to improve self‐management impacts on the early stages of adoption as the reality of the technology requires substantial thought and action. Areas for intervention to improve IPT incorporation include establishing who is responsible for management tasks of the device and enabling navigation to further means of support and resources. 相似文献8.
Economic costs of diabetes in the US in 2002 总被引:40,自引:0,他引:40
OBJECTIVE: Diabetes is the fifth leading cause of death by disease in the U.S. Diabetes also contributes to higher rates of morbidity-people with diabetes are at higher risk for heart disease, blindness, kidney failure, extremity amputations, and other chronic conditions. The objectives of this study were 1). to estimate the direct medical and indirect productivity-related costs attributable to diabetes and 2). to calculate and compare the total and per capita medical expenditures for people with and without diabetes. RESEARCH DESIGN AND METHODS: Medical expenditures were estimated for the U.S. population with and without diabetes in 2002 by sex, age, race/ethnicity, type of medical condition, and health care setting. Health care use and total health care expenditures attributable to diabetes were estimated using etiological fractions, calculated based on national health care survey data. The value of lost productivity attributable to diabetes was also estimated based on estimates of lost workdays, restricted activity days, prevalence of permanent disability, and mortality attributable to diabetes. RESULTS-Direct medical and indirect expenditures attributable to diabetes in 2002 were estimated at 132 billion US dollars. Direct medical expenditures alone totaled 91.8 billion US dollars and comprised 23.2 billion US dollars for diabetes care, 24.6 billion US dollars for chronic complications attributable to diabetes, and 44.1 billion US dollars for excess prevalence of general medical conditions. Inpatient days (43.9%), nursing home care (15.1%), and office visits (10.9%) constituted the major expenditure groups by service settings. In addition, 51.8% of direct medical expenditures were incurred by people >65 years old. Attributable indirect expenditures resulting from lost workdays, restricted activity days, mortality, and permanent disability due to diabetes totaled 39.8 billion US dollars. U.S. health expenditures for the health care components included in the study totaled 865 billion US dollars, of which 160 billion US dollars was incurred by people with diabetes. Per capita medical expenditures totaled 13243 US dollars for people with diabetes and 2560 US dollars for people without diabetes. When adjusting for differences in age, sex, and race/ethnicity between the population with and without diabetes, people with diabetes had medical expenditures that were approximately 2.4 times higher than expenditures that would be incurred by the same group in the absence of diabetes. CONCLUSIONS: The estimated 132 billion US dollars cost likely underestimates the true burden of diabetes because it omits intangibles, such as pain and suffering, care provided by nonpaid caregivers, and several areas of health care spending where people with diabetes probably use services at higher rates than people without diabetes (e.g., dental care, optometry care, and the use of licensed dietitians). In addition, the cost estimate excludes undiagnosed cases of diabetes. Health care spending in 2002 for people with diabetes is more than double what spending would be without diabetes. Diabetes imposes a substantial cost burden to society and, in particular, to those individuals with diabetes and their families. Eliminating or reducing the health problems caused by diabetes through factors such as better access to preventive care, more widespread diagnosis, more intensive disease management, and the advent of new medical technologies could significantly improve the quality of life for people with diabetes and their families while at the same time potentially reducing national expenditures for health care services and increasing productivity in the U.S. economy. 相似文献
9.
Deletion of the gene encoding p60 in Listeria monocytogenes leads to abnormal cell division and loss of actin-based motility 总被引:11,自引:0,他引:11
Protein p60 encoded by the iap gene is regarded as an essential gene product of Listeria monocytogenes. Here we report, however, the successful construction of a viable iap deletion mutant of L. monocytogenes EGD. The mutant, which produces no p60, shows abnormal septum formation and tends to form short filaments and hooked forms during logarithmic growth. These abnormal bacterial cells break into almost normal sized single bacteria in the late-stationary-growth phase. The iap mutant is strongly attenuated in a mouse model after intravenous injection, demonstrating the importance of p60 during infection, and the invasiveness of the Deltaiap mutant for 3T6 fibroblasts and Caco-2 epithelial cells is slightly reduced. Upon uptake by epithelial cells and macrophages, the iap mutant escapes from the phagosome into the cytosol with the same efficiency as the wild-type strain, and the mutant bacteria also grow intracellularly at a rate similar to that of the wild-type strain. Intracellular movement and cell-to-cell spread are drastically reduced in various cell lines, since the iap-negative bacteria fail to induce the formation of actin tails. However, the bacteria are covered with actin filaments. Most intracellular bacteria show a nonpolar and uneven distribution of ActA around the cell, in contrast to that for the wild-type strain, where ActA is concentrated at the old pole. In an iap(+) revertant strain that produces wild-type levels of p60, intracellular movement, cell-to-cell spread, and polar distribution of ActA are fully restored. In vitro analysis of ActA distribution on the filaments of the Deltaiap strain shows that the loss of bacterial septum formation leads to ActA accumulation at the presumed division sites. In the light of data presented here and elswhere, we propose to rename iap (invasion-associated protein) cwhA (cell wall hydrolase A). 相似文献
10.