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21.
Advances in Health Sciences Education - Spaced education is a learning strategy to improve knowledge acquisition and retention. To date, no robust evidence exists to support the utility of spaced...  相似文献   
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BACKGROUND: There are increasing numbers of older African-Caribbeans in the UK. Primary care staff often feel less confident about diagnosing depression in this group. Screening instruments may assist in making diagnoses in cross-cultural consultations. OBJECTIVE: We aimed to determine the sensitivity and specificity of screening instruments for depression in older African-Caribbean people in Manchester, UK. METHODS: We carried out a two-stage study to compare three screening instruments for depression (Geriatric Depression Scale, Brief Assessment Schedule Depression Cards, Caribbean Culture Specific Screen), with a computerized diagnostic interview for mental health disorders in older adults (Geriatric Mental State). The study was set in inner-city Manchester. The subjects were community-resident African-Caribbeans aged 60 years and over; 227 subjects were approached. Of the 160 people screened, 130 agreed to diagnostic interview. The main outcome measures were Spearman correlation coefficients; these were calculated between each screening instrument and the diagnostic interview. Receiver-operating characteristic (ROC) curve analysis was used to determine appropriate sensitivity and specificity for each instrument. RESULTS: The results for the largest subgroup, the Jamaicans (n = 96/130), demonstrated highly significant correlations between screening instruments and diagnostic interview (P < 0.001). Each instrument had a high sensitivity: Brief Assessment Schedule depression cards (cut-off > or =6; sensitivity 90.9% (95% CI 58.8-99.8), specificity 82.1% (95% CI 74.0-90.3)), Caribbean Culture Specific Screen (cut-off > or =6; sensitivity 90.9% (95% CI 58.8-99.8), specificity 74.1% (95% CI 64.8-83.4)), and Geriatric Depression Scale (cut-off > or =4; sensitivity 100% (95% CI 97.1-100), specificity 69.1% (95% CI 59.6-79.2)). CONCLUSIONS: These screening instruments demonstrate high sensitivity levels, if an appropriate cut-off point is used. The culture-specific instrument did not perform better than the traditional instruments. Health professionals should approach the consultation in a culturally sensitive manner and use the validated instrument they are most familiar with.  相似文献   
24.
The lactol derivative of a lactone cyclooxygenase-2 inhibitor (DFU) was evaluated in vivo and in vitro for its potential suitability as a prodrug. DFU-lactol was found to be 10 to 20 times more soluble than DFU in a variety of aqueous vehicles. After administration of DFU-lactol at 20 mg kg-1 p.o. in rats, a Cmax of 7.5 microM DFU was reached in the plasma. After oral administration, the ED50s of DFU-lactol in the carrageenan-induced paw edema and lipopolysaccharide-induced pyresis assays in rats are comparable with the ED50s observed when dosing with DFU. Incubations of DFU-lactol with rat and human hepatocytes demonstrated that the oxidation of DFU-lactol can be mediated by liver enzymes and that a competing pathway is direct glucuronidation of the DFU-lactol hydroxyl group. Assays with subcellular fractions from rat liver indicated that most of the oxidation of DFU-lactol occurs in the cytosolic fraction and requires NAD(P)+. Human liver cytosol can also support the oxidation of DFU-lactol to DFU when NAD(P)+ is added to the incubations. Fractionation of human liver cytosolic proteins showed that at least three enzymes are capable of efficiently effecting the oxidation of DFU-lactol to DFU. Incubations with commercially available dehydrogenases suggest that alcohol and hydroxysteroid dehydrogenases are involved in this oxidative process. These data together suggest that lactols may represent useful prodrugs for lactone-containing drugs.  相似文献   
25.
The antigenic epitopes of the MNSs blood groups are localized on alpha and delta glycophorins (glycophorins A and B) of the erythrocyte surface. Hil, SJL, Mur, and Hop antisera define the Miltenberger (Mi) complex of MiV, MiJ.L., MiIII, and MiVI variant serologic phenotypes of this blood group system. We report here the location of the epitopes for antibodies in these antisera. The antigens of these Mi classes are variant glycophorins that are hybrids of alpha and delta glycophorins in alpha-delta and delta-alpha-delta arrangements. The hybrid junctions give rise to novel polypeptide sequences not present in the parent glycophorins; in MiIII and MiVI this also includes an expressed sequence of the delta pseudoexon. These sequences are identical in the above Mi-glycophorins occurring in erythrocytes that share a common Mi determinant. Four peptides of 10 to 14 amino acids each were constructed to be homologous to the identical sequences; they were designated, "Hil", "SJL", "Mur", and "Hop" to reflect the common determinant. The peptides were tested for inhibition of reaction of appropriate cells with the relevant antisera. The Hil peptide, outlining the alpha-delta s junction region in MiIII, MiV, and MiVI glycophorins, inhibited the reaction of respective erythrocytes (red blood cells [RBCs]) with anti-Hil. The SJL peptide, which differs from the Hil peptide by a single Thr----Met substitution, was specific for inhibition of the reaction of MiJ.L. RBCs with anti-SJL (an example of anti-S specific for such RBCs). The Hop peptide, which corresponds to the delta-alpha junction in MiVI glycophorin, inhibited the hemagglutination of MiVIII RBCs by anti-Hop. MiVI and MiVIII glycophorins share an identical sequence at that site. The Mur peptide, corresponding to a portion of the expressed pseudoexon sequence in MiIII and MiVI glycophorins, was specific for inhibition of the reaction of MiIII and MiVI RBCs with anti-Mur. The peptides had no effect on the hemagglutination of control MNSs RBCs by their respective antisera nor of unrelated Mi classes RBCs by antisera that distinguish these classes. We conclude that the alpha-delta junction in MiIII, MiV, and MiVI glycophorins outlines the epitopes for anti-Hil, the alpha-delta junction in MiJ.L. outlines the epitope for anti-SJL, the delta-alpha junction in MiVI constitutes the epitope for anti-Hop, and the expressed delta pseudoexon sequence in MiIII and MiVI constitutes the epitope for anti-Mur.  相似文献   
26.
Leavitt  SA; DeAngelo  AB; George  MH; Ross  JA 《Carcinogenesis》1997,18(11):2101-2106
Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.   相似文献   
27.
Female sterilisation is an important component of National Family Welfare Programme. The target group is best motivated during the puerperium for such a procedure. However laparoscopic sterilisation which has got some distinct advantages, is not technically feasible at this time. The authors have used a technique where the advantages of cosmetic appearance, reduced post operative morbidity and reversibility can be conferred on the puerperal women.After trying out the method individually in some cases, a formal case control study design has been made and an evaluation study has been performed in 122 cases. The technique has been found to be cosmetically more acceptable, both at clientele and peer evaluation levels (p<0.001). Though all the four parameters of post operative morbidity have shown better results for the technique evaluated as against the conventional technique, statistical significance has been achieved in two of the parameters (p<0.05).KEY WORDS: Cosmetics, Female sterilisation, Post operative morbidity  相似文献   
28.
Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous inflammatory disorders of the respiratory tract characterized by airflow obstruction. It is now clear that the environmental factors that drive airway pathology in asthma and COPD, including allergens, viruses, ozone and cigarette smoke, activate innate immune receptors known as pattern-recognition receptors, either directly or indirectly by causing the release of endogenous ligands. Thus, there is now intense research activity focused around understanding the mechanisms by which pattern-recognition receptors sustain the airway inflammatory response, and how these mechanisms might be targeted therapeutically. One pattern-recognition receptor that has recently come to attention in chronic airways disease is the receptor for advanced glycation end products (RAGE). RAGE is a member of the immunoglobulin superfamily of cell surface receptors that recognizes pathogen- and host-derived endogenous ligands to initiate the immune response to tissue injury, infection and inflammation. Although the role of RAGE in lung physiology and pathophysiology is not well understood, recent genome-wide association studies have linked RAGE gene polymorphisms with airflow obstruction. In addition, accumulating data from animal and clinical investigations reveal increased expression of RAGE and its ligands, together with reduced expression of soluble RAGE, an endogenous inhibitor of RAGE signalling, in chronic airways disease. In this review, we discuss recent studies of the ligand–RAGE axis in asthma and COPD, highlight important areas for future research and discuss how this axis might potentially be harnessed for therapeutic benefit in these conditions.  相似文献   
29.
Hand‐foot‐skin reaction is a distinct clinical condition arising in association with the use of multikinase inhibitors, including sorafenib. Because multikinase inhibitors are increasingly being used in children with cancer, recognition of this previously unfamiliar condition is of importance to pediatric dermatologists. We describe the diagnosis and successful treatment of a case of hand‐foot‐skin reaction in a child taking sorafenib for an unresectable desmoid tumor.  相似文献   
30.
Nitric oxide (NO) is a powerful vasodilator, involved in both physiological functions and pathophysiological alterations of various regulatory processes, for example, the maintenance of vascular tone and inflammation. The recently demonstrated impact of exogenous NO on the central nervous system extends its role under normal and pathological conditions. At times neuroprotective, at times neurotoxic, NO is capable of different effects depending upon the extent of cerebral damage, the cellular redox state, and the spatiotemporal coordinates and concentration at which it is synthesized. This review provides new insights into the short‐ and long‐term effects of endogenous and exogenous NO in brain injury. ANN NEUROL 2013;73:442–448  相似文献   
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