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971.
In Europe, adolescent substance misuse increased during the 1990s. Ireland has among the highest rates of substance misuse among schoolchildren in Europe. We sought to describe the socio-demographic and drug misuse profile of children presenting to addiction treatment services in Dublin during the 1990s. Of the 9,874 individuals who sought addiction treatment, 1,953 (20%) were aged less than 18 years. There was a sharp increase in the number of children after 1993. The main drug of abuse was an opiate in 48% of cases. Compared to adults, the children were more likely to be female and less likely to inject. As the decade progressed the proportion of girls increased, injecting was reported more frequently and there was a dramatic rise in heroin misuse. Child heroin users were more likely to be female and to be homeless compared to their adult counterparts. This study highlights the need for a dedicated service for child drug users in Dublin.  相似文献   
972.
Having shown a haematopoietic role for Patch (Ph), especially when doubly heterozygous with the mutant Wct (Loutit & Cattanach, 1983) we have similarly examined the Rw locus, the third member of the triplet. Mature Rw/+mice have a just detectable macrocytic anaemia. When doubly heterozygous with Wct and Wv the mild anaemia of these W mutants is exaggerated but with W19H (not anaemic as single heterozygote) red cell factors are as for Rw/+. Rw/+mice are strikingly more sensitive to the lethal effects of X-irradiation (MLD 6.66 +/- 0.10 Gy) on haematopoiesis than comparable +/+ mice (MLD 8 Gy). Those mice that do recover after X-irradiation do not exhibit the delay in recovery of erythropoiesis that is evident with characteristic W mutants in both single and double dose. Furthermore the double heterozygote Wct+/+Rw has a significantly lower MLD (5.19 +/- 0.17 Gy) for X-radiation than Wct/+ (MLD 6.48 +/- 0.24 Gy). We argue that all three loci W, Ph and Rw, influence haematopoietic stem cells, leading to increased radiosensitivity when deletions or mutant genes are present.  相似文献   
973.
The planned MADIT‐CRT trial is designed to determine if CRT‐D will reduce the risk of mortality and HF events by approximately 25% in subjects with ischemic (NYHA class I‐II) and non‐ischemic (NYHA class II) cardiomyopathy, left ventricular dysfunction (EF ≤ 0.30), and prolonged intraventricular conduction (QRS duration ≥ 130 ms).  相似文献   
974.
Acquired pulmonary artery stenosis is rare. There are two main types, firstly intrinsic disease of the pulmonary valve itself, such as carcinoid heart disease. Secondly, extrinsic compression of the pulmonary artery from a mediastinal structure. We report a case of acquired pulmonary supravalvular stenosis due to extrinsic compression by a carcinoid mediastinal tumor, confirmed by echocardiographic imaging/Doppler interrogation and computerized tomography.  相似文献   
975.
Recent advances in travel medicine include the use of computer resources to obtain information on outbreaks and recommendations to travelers, the introduction of atovaquone/proguanil as chemoprophylaxis and treatment for malaria, the use of azithromycin as an alternative in the self-treatment of traveler’s diarrhea, and the combination of hepatitis A and hepatitis B vaccines. At the same time, new challenges continue to appear. Shifts in the distribution of infections, such as West Nile virus and dengue fever, underscore the need for up-to-date information. Well-known infectious diseases, such as polio, meningococcal meningitis, and influenza are appearing in unexpected ways and settings. It is increasingly clear that travelers, while at risk for infections, also play a role in the global dispersal of pathogens, such as certain serogroups of Neisseria meningitidis and influenza. Increasing drug resistance affects the choice of drugs for treatment and chemoprophylaxis, and decisions about use of vaccines. Newly identified adverse events associated with yellow fever vaccine have prompted enhanced surveillance after vaccination and careful scrutiny of appropriate indications for the vaccine.  相似文献   
976.
BACKGROUND: Carbohydrate deficient transferrin (CDT), a biochemical marker of chronic alcohol consumption, is used by researchers and clinicians alike in a variety of populations. Levels of CDT may be affected by certain types of medical illnesses and conditions. Thus the interpretation of CDT results may need to be carefully examined in these populations. Because CDT is synthesized, glycosylated, and secreted by the liver, the use of CDT values in patients with liver disease has been an area of focused interest. METHODS: We evaluated the CDT values of 79 abstaining patients with end-stage liver disease. These patients were recruited from a liver transplant clinic while they were listed and waiting for transplantation. Patients were determined to be abstaining both by interview and by random blood alcohol levels in those with a diagnosis of alcoholic liver disease. The severity of the liver disease was categorized by the Child-Pugh score. Correlations were determined between CDT values and liver enzymes, and Child-Pugh scores and liver diagnosis. RESULTS: Nearly 50% of the patients had a CDT value of 2.6% or above, indicating a clinically positive value. There were strong correlations between CDT and a number of biochemical and physical variables, most importantly the Child-Pugh score (r = 0.52, p = 0.000). Specific liver diseases were not associated with absolute CDT values. However, patients with hepatitis C (HCV) had a significantly higher chance of having a clinically positive CDT compared with patients with other types of liver diseases. CONCLUSIONS: These results suggest that an elevated CDT value may not accurately represent alcohol consumption in patients with advanced liver disease. In fact, in such patients, the CDT may become a marker for the degree of liver impairment in alcoholic and nonalcoholic liver disease. CDT values should be viewed with caution in any patient with liver disease especially when the degree of cirrhosis reaches a Child-Pugh score of C (total score of 10 or above).  相似文献   
977.
OBJECTIVE: To examine the association between N-acetyl transferase (NAT) genotype (NAT1 and NAT2) and risk of developing systemic lupus erythematosus (SLE). METHODS: DNA samples were collected from 243 recently diagnosed cases and 298 controls enrolled in a population based case-control study conducted in 60 counties in North Carolina and South Carolina, USA. RESULTS: There was no association between SLE and NAT1 genotype (OR 0.96, 95% CI 0.65, 1.4 for the presence of a *10 allele) or NAT2 genotype (OR 1.1, 95% CI 0.73, 1.6 for the slow- compared with fast-acetylation genotype). We saw some evidence of interaction between NAT genotypes and use of hair dyes (a source of arylamines), with higher risk seen among hair dye users who had both the *10 NAT1 allele and the NAT2 slow-acetylation genotype (OR 2.9, 95% CI 1.2, 6.9 in this subgroup compared with all others). CONCLUSION: Our results suggest that although there is little overall association between NAT genotypes and risk of developing SLE, the interaction between NAT1 and NAT2 and specific exposures such as hair dyes may be important. This finding highlights the need to consider exposure when assessing genetic susceptibility.  相似文献   
978.
BACKGROUND: Recurrent pregnancy loss (RPL) is a significant clinical problem. Recently, thrombophilias have been implicated as a possible cause. Factor V Leiden (FVL) and prothrombin gene (G20210A) mutations are the most common types of hereditary thrombophilias, but are usually undiagnosed because most carriers are asymptomatic. The relationship between FVL, G20210A, and RPL has been investigated with conflicting results. This study analyzed existing data to determine whether an association exists. METHODS: A systematic review of the literature was performed. Only case-control studies that defined RPL as 2 or more pregnancy losses in the first or second trimester and that confirmed mutations by DNA analysis were included. Sixteen studies were selected for the FVL meta-analysis and 7 for the G20210A analysis. Stratified and multivariate logistic regression analyses were performed with the use of aggregate data. Results were confirmed by means of fixed- and random-effects meta-analyses models. RESULTS: The combined odds ratios for the association between RPL and FVL and between RPL and G20210A were 2.0 (95% confidence interval, 1.5-2.7; P<.001) and 2.0 (95% confidence interval, 1.0-4.0; P =.03), respectively. Similar results were produced by the logistic regression and both fixed- and random-effects meta-analysis models. CONCLUSIONS: Carriers of FVL or prothrombin gene mutations have double the risk of experiencing 2 or more miscarriages compared with women without thrombophilias. Hereditary thrombophilias may be an unrecognized cause of RPL. We recommend testing for these mutations in women with RPL.  相似文献   
979.
We describe the validation of a method for the simultaneous analysis of 29 synthetic cannabinoids (SCs) and metabolites, 4 amphetamines, and 2 cannabinoids in human whole blood. This method enables one analysis to cover what previously required multiple analyses for these classic and novel drugs‐of‐abuse with diverse physicochemical properties. The scope of targeted analytes was based on the most prevalent drugs‐of‐abuse and SCs encountered at the New Zealand border in 2017 and included parent compounds and metabolites belonging to the indole and indazole carboxamide, quinolinyl indole carboxylate, and naphthoylindole classifications. Samples were prepared by supported‐liquid‐extraction (SLE) followed by liquid chromatography?tandem mass spectrometry (LC?MS/MS) analysis with positive electrospray ionization (ESI). The method was validated with respect to selectivity, matrix effects, process efficiency, sensitivity, repeatability, extract stability, and carryover for qualitative confirmation. Linearity as well as accuracy and precision data at target decision concentrations were also evaluated. The limits of detection and confirmation ranged from 0.1 to 6.0 ng/mL and 1.0 to 6.0 ng/mL, respectively. The described method was successfully applied to the analysis of 564 ante‐ and post‐mortem blood samples in 2018. There were 132 cases (23%) with positive findings of at least one SC, with the five most commonly detected SCs being AMB‐FUBINACA and/or acid (61%), 5F‐ADB and/or acid (40%), ADB‐FUBINACA (11%), 5F‐MDMB‐PICA acid (6%), and MDMB‐FUBINACA acid (6%). The results also demonstrate the predominant presence of metabolites at higher levels than the unchanged parent SCs in blood, highlighting the need to maintain forensic screening methods capable of the simultaneous detection of both parent compounds and metabolites.  相似文献   
980.
ContextThe Veterans Health Administration (VA) National Center for Ethics in Healthcare implemented the Life-Sustaining Treatment Decisions Initiative, including policy and practice standards, clinician communication training, a documentation template, and central implementation support to foster advance care planning via goals-of-care conversations for seriously ill veterans in 2014, spreading nationally to other Veterans Health Affairs (VA) sites in 2017.ObjectivesOur goal was to describe the range of early implementation experiences among the pilot sites, and compare them with spread sites that implemented LSTDI about two years later, identifying cross-site best practices and pitfalls.MethodsWe conducted semistructured interviews with 32 key stakeholders from 12 sites to identify cross-site best practices and pitfalls related to implementation.ResultsThree primary implementation themes emerged: organizational readiness for transformation, importance of champions, and time and resources needed to achieve implementation. Each theme's barriers and facilitators highlighted variability in success based on complexity in terms of vertical hierarchy and horizontal cross-role/cross-clinic relationships.ConclusionLearning health care systems need multilevel interdisciplinary implementation approaches to support communication about serious illness, from broad-based system-level training and education to build communication skills, to focusing on characteristics of successful individual champions who listen to critics and are tenacious in addressing concerns.  相似文献   
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