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11.
Yatin Mehta Abhinav Gupta Subhash Todi SN Myatra D. P. Samaddar Vijaya Patil Pradip Kumar Bhattacharya Suresh Ramasubban 《Indian Journal of Critical Care Medicine》2014,18(3):149-163
These guidelines, written for clinicians, contains evidence-based recommendations for the prevention of hospital acquired infections Hospital acquired infections are a major cause of mortality and morbidity and provide challenge to clinicians. Measures of infection control include identifying patients at risk of nosocomial infections, observing hand hygiene, following standard precautions to reduce transmission and strategies to reduce VAP, CR-BSI, CAUTI. Environmental factors and architectural lay out also need to be emphasized upon. Infection prevention in special subsets of patients - burns patients, include identifying sources of organism, identification of organisms, isolation if required, antibiotic prophylaxis to be used selectively, early removal of necrotic tissue, prevention of tetanus, early nutrition and surveillance. Immunodeficient and Transplant recipients are at a higher risk of opportunistic infections. The post tranplant timetable is divided into three time periods for determining risk of infections. Room ventilation, cleaning and decontamination, protective clothing with care regarding food requires special consideration. Monitoring and Surveillance are prioritized depending upon the needs. Designated infection control teams should supervise the process and help in collection and compilation of data. Antibiotic Stewardship Recommendations include constituting a team, close coordination between teams, audit, formulary restriction, de-escalation, optimizing dosing, active use of information technology among other measure. The recommendations in these guidelines are intended to support, and not replace, good clinical judgment. The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of evidence supporting the recommendation, so that readers can ascertain how best to apply the recommendations in their practice environments. 相似文献
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The amino acid intermediate homocysteine (Hcy) is formed during the metabolism of methionine to cysteine. Hyperhomocysteinemia (HHcy) is recognized as an independent risk factor for coronary atherosclerosis. The circulating levels of total Hcy (tHcy) can increase due to intake of foods rich in methionine or deficiencies of vitamins such as folate, pyridoxine and cyanocobalamin, which are required for the metabolism of Hcy. In addition, mutations in the genes coding for Hcy metabolizing enzymes can contribute to an increase in tHcy levels. Clinical and epidemiological studies have shown that an elevated level of tHcy measured in serum or plasma is a strong predictor of cardiovascular disease risk, which appears to be greatest in patients who have HHcy following a methionine load. Intimal hyperplasia (IH) (intima/media [I/M] ratio) is the universal response of a vessel to injury and may result in vasoconstriction when left unattended. The effect of dietary HHcy on balloon catheter-injured carotid artery and its modulation (if any) by the peroxisome proliferator-activated receptor agonist gamma rosiglitazone was evaluated in 12-week-old female Sprague-Dawley rats fed either a control diet or a diet containing 1% L-methionine. Once the rats were established on the diet, the group that was fed 1% L-methionine was further subdivided and either given an aqueous preparation of 3 mg/kg/day rosiglitazone or the vehicle via oral gavage for one week. This was followed by surgically injuring the left carotid artery using a Maverick Over-The-Wire catheter (2.0 mm × 20 mm, 3.2F; Boston Scientific, USA). The rats were continued on their respective diets and drug regimen for 21 days postsurgery. On day 22 of the procedure, the rats were sacrificed for collection of blood, the carotid arteries and liver for biochemical and histological evaluation. Compared with controls there was a significant increase in both tHcy levels and I/M ratio in the rats fed 1% L-methionine (5.4±0.28 μM versus 32.8±3.01 μM, P<0.002; and 0.175±0.05 versus 1.05±0.23, P<0.005, respectively). The effect of rosiglitazone in rats fed the control diet was not prominent. On the other hand, administration of rosiglitazone to the rats on the 1% L-methionine diet significantly reduced the levels of serum tHcy (16.6±2.1 μM versus 32.8±3.01 μM, P<0.001); however, the tHcy levels remained significantly elevated compared with animals on the control diet (P<0.002). The group receiving the L-methionine diet plus rosiglitazone had an inhibition in the development of IH compared with those receiving the L-methionine diet alone (I/M of 0.278±0.041 versus 1.05±0.23, P<0.01). Moreover, the development of IH in the group receiving the L-methionine diet plus rosiglitazone treatment was not significantly different from that observed in the group on the control diet without rosiglitazone (0.278±0.041 versus 0.175±0.05, respectively). These findings may have important implications in deciphering the molecular mechanisms involved in the augmentation of IH in HHcy and modulation of this process by rosiglitazone. 相似文献
14.
Background
The objective of this study was to demonstrate the use of an association rule mining approach to discover associations between selected socioeconomic variables and the four most leading causes of cancer mortality in the United States. An association rule mining algorithm was applied to extract associations between the 1988–1992 cancer mortality rates for colorectal, lung, breast, and prostate cancers defined at the Health Service Area level and selected socioeconomic variables from the 1990 United States census. Geographic information system technology was used to integrate these data which were defined at different spatial resolutions, and to visualize and analyze the results from the association rule mining process. 相似文献15.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
相似文献
16.
AM VOGEL D LENNON SN AMERATUNGA J HOLYOAKE 《Journal of paediatrics and child health》1996,32(6):484-490
Objective : To establish the prevalence of specific chronic conditions of childhood in the Auckland area and to quantify resource use by these children.
Methodology : Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.
Results : The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.
Conclusions : There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs. 相似文献
Methodology : Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.
Results : The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.
Conclusions : There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs. 相似文献
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K-Ⅱ系k阿片激动剂U-50488的同类物。通过部分离体和整体实验比较了K-Ⅱ与U-50488的药理作用。实验发现,K-Ⅱ抑制电刺激兔输精管收缩的IC50值为0.42 nmol/L,U-50488为26.5 nmol/L;K-Ⅱ抑制小鼠运动功能(横筛法)的ED50值为1.7 mg/g,U-50488为15.3 mg/kg;K-Ⅱ的小鼠LD50值为152.5 mg/kg,U-50488为118.4 mg/g;K-Ⅱ明显降低小鼠自发活动的作用比U-50488强5倍。结果表明,K-Ⅱ是一个药理作用较U-50488强的k受体激动剂。 相似文献
19.
This randomised, double-blind study conducted at nine sites in the UK and the Netherlands compared the safety and antidepressant efficacy of venlafaxine and dothiepin. Ninety-two geriatric patients (aged 64-87 years) with major depression were randomly assigned to receive either venlafaxine or dothiepin for up to 43 days. The dose of venlafaxine or dothiepin was titrated up to a maximum of 150 mg per day for the first 15 days, and thereafter could range from 50 to 150 mg per day. Adjusted mean scores on the MADRS and the HAM-D decreased significantly (p 0.05) from baseline to the end of the study in both groups. A response to therapy was observed in 60% of patients in the venlafaxine group and 53% of patients in the dothiepin group on the MADRS, and in 60% of patients in both groups on the HAM-D. Suicidal ideation scores on the MADRS were significantly (p=0.042) lower in the venlafaxine group at week 6. Treatment-emergent study events were the primary reason for withdrawal in only 7% of venlafaxine-treated patients and 8% of dothiepin-treated patients. The results confirm the efficacy and tolerability of venlafaxine for treating major depression in the elderly. 相似文献
20.
Infusible platelet membrane microvesicles: a potential transfusion substitute for platelets 总被引:8,自引:0,他引:8
FC Chao ; BK Kim ; AM Houranieh ; FH Liang ; MW Konrad ; SN Swisher ; JL Tullis 《Transfusion》1996,36(6):536-542
BACKGROUND: Several substitutes for intact, viable platelets have been used for transfusion, both to people and in animal models, with varied success. Infusible platelet membrane (IPM) is prepared from human platelets. IPM retains the glycoprotein (GP)lb receptor and has platelet factor 3 activity (procoagulant activity). However, factor V, serotonin, a cytoplasmic marker enzyme (purine nucleotide phosphorylase), GPIIb/IIIa complex, and HLA class I and II antigens are all absent in IPM. STUDY DESIGN AND METHODS: IPM is prepared from outdated platelets. The platelets were disrupted by freezing and thawing; they were washed and heated to inactivate possible viral contaminants, and then the sonicated membrane microvesicle fraction was separated and lyophilized. The hemostatic activity of IPM was measured by its ability to reduce the prolonged bleeding time in thrombocytopenic rabbits. RESULTS: Administration of IPM at a dose of 2 mg per kg results in a substantial reduction in the bleeding time. In a series of 23 experiments, a median preinjection bleeding time of 15 minutes was reduced to 6 minutes within 4 hours after IPM administration. Administration of IPM did show a mild enhancement in the thrombogenicity index, as measured in the Wessler rabbit model. This enhancement is, however, not significant, as a thrombogenicity index value of up to 0.6 is clinically acceptable. CONCLUSION: IPM may have clinical potential as a substitute for platelets in the treatment of bleeding due to thrombocytopenia. 相似文献