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41.
EMMA LAING PAUL ASHLEY FARHAD B. NAINI & DALJIT S. GILL 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2009,19(3):155-162
Objective. The use of a space maintainer appliance, or restoration of a carious primary tooth that can then act as a natural space maintainer, may potentially obviate the consequences of loss of arch length and the need for complex orthodontic treatment at a later stage. Nevertheless, all space maintainer appliances are plaque retentive and may predispose to dental caries and gingival inflammation. Space maintainer appliances may also impinge on the soft tissues, interfere with eruption of adjacent teeth, fracture, and become dislodged or lost. This review article provides a summary of the available evidence, and considers the indications for space maintenance.
Methods. Medline and Ovid Medline were scanned, and additionally a hand-search of non-listed peer-reviewed papers written in English was performed. A total of 16 pertinent papers published between 1987 and 2007 that satisfied the inclusion criteria were selected for discussion.
Conclusions. There is limited evidence to recommend either for or against the use of space maintainers to prevent or reduce the severity of malocclusion in the permanent dentition. Decisions regarding the use of space maintainers should be guided by balancing the occlusal disturbance that may result if one is not used against the potential plaque accumulation and caries that the appliance may cause. 相似文献
Methods. Medline and Ovid Medline were scanned, and additionally a hand-search of non-listed peer-reviewed papers written in English was performed. A total of 16 pertinent papers published between 1987 and 2007 that satisfied the inclusion criteria were selected for discussion.
Conclusions. There is limited evidence to recommend either for or against the use of space maintainers to prevent or reduce the severity of malocclusion in the permanent dentition. Decisions regarding the use of space maintainers should be guided by balancing the occlusal disturbance that may result if one is not used against the potential plaque accumulation and caries that the appliance may cause. 相似文献
42.
Severity of dependence and route of administration of heroin, cocaine and amphetamines 总被引:2,自引:0,他引:2
MICHAEL GOSSOP PAUL GRIFFITHS BEVERLY POWIS JOHN STRANG 《Addiction (Abingdon, England)》1992,87(11):1527-1536
This study investigates severity of dependence upon heroin, cocaine and amphetamines in a group of 200 heroin users, 75% of whom were not in contact with any treatment agency. For drug takers who were current users of more than one drug, heroin produced more severe dependence than either cocaine or amphetamine and many users of these stimulant drugs reported having experienced no problems of dependence. Severity of dependence was influenced by route of administration as welt as type of drug. Heroin taken by injection was associated with more severe dependence than smoked heroin. For cocaine, injection and smoking were associated with equivalent dependence ratings, and both of these routes were associated with more severe dependence than cocaine used intranasally. For amphetamine, there were no differences in severity of dependence ratings for injection, intranasal or oral use. Severity of dependence was correlated with dose and duration of drug use; it was also associated with previous attendance at a drug treatment agency, though dependence problems were also common among heroin users who had never received treatment. Implications of these findings are discussed. 相似文献
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44.
Variable expression of the murine natural resistance gene Lsh in different macrophage populations infected in vitro with Leishmania donovani 总被引:5,自引:0,他引:5
Various macrophage populations isolated from mice (including congenic C57BL/10ScSn and B10.LLshr) bearing resistant or susceptible alleles for the natural resistance gene (Lsh) were infected with Leishmania donovani amastigotes in vitro and examined (a) for their ability to support growth of the amastigote population over 7 days of culture in vitro, and (b) for their ability to express Lsh gene controlled resistance and susceptibility in vitro. Resident macrophages from liver (Kupffer cells), spleen and lung, as well as 7-day bone marrow-derived macrophages and bone marrow macrophages obtained after 6 weeks of continuous culture in vitro, all supported growth of the amastigote population. Of these, significant differences in amastigote numbers in macrophages from Lshs and Lshr mice were observed after 48 h of infection in vitro for liver, lung and 7-day bone marrow macrophage populations only. Resident peritoneal macrophages grown in adherent or suspension cultures neither supported growth of the amastigote population nor showed any evidence of Lsh gene expression in vitro. Hence, multiplication of the parasite appeared to be a necessary but not sufficient condition for observation of Lsh gene activity against L. donovani in vitro. Use of tritiated thymidine incorporation and autoradiography to label dividing amastigotes showed equivalent multiplication of the parasite in liver macrophages from Lshs and Lshr mice between 24 h and 48 h after infection in vitro, with a dramatic difference observed thereafter. This was consistent with earlier observations of a 2-3 day delay in expression of Lsh gene controlled resistance in vivo. Comparison with studies using Salmonella typhimurium and Mycobacterium bovis suggests that the gene may be restricted in its action to a particular point in the parasite cell cycle, perhaps at the level of regulating DNA replication. 相似文献
45.
PAUL L. FIDEL 《International reviews of immunology》2013,32(6):515-548
Recurrent vulvovaginal candidiasis (RVVC) is a significant problem in women of childbearing ages and is caused by Candida albicans, a commensal organism of the intestinal and reproductive tracts. As a result of this commensalism, most healthy individuals have demonstrable Candida -specific adaptive immunity that is considered protective. In women with RVVC, a deficiency/dysfunction of this protective immunity is postulated to affect susceptibility to infection. Although cell-mediated immunity (CMI) is considered important for protection against mucosal candidal infections, little is understood about specific host defenses that are important at the vaginal mucosa. Studies to date suggest that a compartmentalized local, rather than systemic, immunity is important for defense against vaginitis. This review will summarize the current state of knowledge regarding protective host defense mechanisms against vaginal C. albicans infections both from clinical studies and animal models. From these data, hypotheses are presented for what host defense mechanisms appear important for resistance/susceptibility to vaginal infection. 相似文献
46.
A New Variant of Hereditary Hemolytic Anemia With Stomatocytosis and Erythrocyte Cation Abnormality 总被引:4,自引:1,他引:4
MILLER DENIS R.; RICKLES FREDERICK R.; LICHTMAN MARSHALL A.; LA CELLE PAUL L.; BATES JONATHAN; WEED ROBERT I. 《Blood》1971,38(2):184-204
A new variant of congenital hemolyticanemia associated with stomatocytosis,reticulocytosis, decreased osmotic fragility, type I autohemolysis and shortened erythrocyte survival without specific splenic sequestration was discoveredin three siblings of Swiss-German ancestry. Increased intracellular sodium(two to three times normal) and slightlydecreased intracellular potassium weredetected. Total sodium efflux was eight-fold greater than normal but total potassium influx was normal and ouabain-sensitive potassium influx was decreased.The ouabain-sensitive sodium efflux:potassium influx ratio was 26:1 ratherthan the 3:2 ratio noted in normal cells.The consanguineous parents, four othersiblings, and 44 other family membershad mild stomatocytosis, reticulocytosis,and, when studied, decreased osmoticfragility, increased autohemolysis, intermediate abnormalities of cation content,cation flux, and moderate shortening oferythrocyte survival. Autosomal dominant inheritance was suggested. Noabnormalities of RBC enzymes, hemoglobin or lipids were observed. No abnormalities of membrane protein weredetected on acrylamide gel. Substratedepletion of these hypermetabolic cellsresulted in intracellular dehydrationwith potassium loss in excess of sodiumgain and decreased deformability. Although the exact nature of the defectresponsible for hemolysis is unknown,this syndrome differs from other hereditary hemolytic anemias associated withstomatocytosis. Submitted on December 21, 1970 Revised on March 16, 1971 Accepted on March 29, 1971 相似文献
47.
Acute Stridor in Achalasia of the Esophagus (Cardiospasm) 总被引:1,自引:0,他引:1
48.
JÜRGEN KUSCHYK M.D. GORAN MILASINOVIC M.D. Ph.D VOLKER KÜHLKAMP M.D. PAUL R. ROBERTS M.D. MARKUS ZABEL M.D. FRANCK MOLIN M.D. STEPHEN SHOROFSKY M.D. Ph.D F.H.R.S. KURT D. STROMBERG M.S. PAUL J. DEGROOT M.S. FRANCIS D. MURGATROYD M.D. SOLO STUDY INVESTIGATORS 《Journal of cardiovascular electrophysiology》2014,25(1):29-35
49.
50.
Michael L. ALOSCO Andreana BENITEZ John GUNSTAD Mary Beth SPITZNAGEL Jeanne M. MCCAFFERY John E. MCGEARY Athena POPPAS Robert H. PAUL Lawrence H. SWEET Ronald A. COHEN 《Psychogeriatrics》2013,13(1):35-40
Background: Much attention has been paid to the prevalence and predisposition of the fat mass and obesity‐associated (FTO) gene to obesity, although only a few studies have characterized the extent to which this affects cognitive function. This study examined differences between risk allele carriers (i.e. FTO‐AC/AA) and non‐carriers (i.e. FTO‐CC) on indices of attention/executive function/psychomotor speed, memory, language, and visual‐spatial ability in a sample of older patients with cardiovascular disease. Methods: We recruited 120 older adults from an outpatient cardiology clinic who underwent blood draw and completed neuropsychological testing. Participants were classified into two groups: one for those who were homozygous for the non‐risk‐conferring allele (i.e. FTO‐CC) (n= 49) and the other for those who had at least one copy of the obesity risk‐conferring A allele (i.e. FTO‐AC/AA) (n= 71). Results: Mancova analyses adjusting for age and years of education revealed the FTO‐AC/AA group performed significantly worse on indices of memory (λ= 0.94, F(2, 115) = 3.58, P= 0.03, partial η2= 0.06). Follow‐up tests revealed a significant effect for the FTO‐AC/AA group, relative to the non‐carrier group, on encoding (i.e. California Verbal Learning Test Total Learning) and California Verbal Learning Test long‐delay free recall (P < 0.05). No such differences between FTO carriers and non‐carriers emerged on tests of attention/executive function/psychomotor speed, language, or visual‐spatial ability (P > 0.05 for all). Conclusions: These findings suggest that the FTO risk allele is associated with reduced memory performance, particularly on aspects of memory encoding and delayed recall. To elucidate underlying mechanisms, these findings will need to be replicated in larger samples that utilize neuroimaging. 相似文献