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排序方式: 共有2310条查询结果,搜索用时 15 毫秒
21.
Vance J. Yates Abla M. El Mishad Kenneth J. McCormick John J. Trentin 《Infection and immunity》1973,7(6):973-980
An 18- to 20-nm virus particle was isolated from the Olson strain of quail bronchitis, an avian adenovirus. On density gradient separation the small virions were primarily found at densities of 1.39 and 1.42 g/cm(3). The majority of the infectious particles were at the heavier density. The virus had a hexagonal outline and contained single-stranded deoxyribonucleic acid. It was resistant to heating at 56 C for more than an hour and was not inactivated by treatment with chloroform or low pH. Purified virus did not agglutinate erythrocytes of various avian and mammalian species. Replication of the small particles occurred either in chicken embryos or in cultures of embryo kidney cells coinfected with an adenovirus helper. Antigenically the virus was distinct from the adeno-associated viruses types 1, 2, 3, and 4. The virus is the avian equivalent of the adeno-associated viruses of primates and lower animals. 相似文献
22.
Alcohol and physical inactivity are risk factors for a variety of cancer types. However, alcohol use often co-occurs with physical activity (PA), which could mitigate the cancer-prevention benefits of PA. Alcohol is integrated into the culture of one of the most popular physical activities for adults in the United States (U.S.), golf. This study examined how alcohol use was associated with total PA, golf-specific PA, and motives for golfing in a national sample of golfers in the U.S. Adult golfers (n = 338; 51% male, 81% White, 46 ± 14.4 years) self-reported alcohol use, golfing behavior and motives, and PA. Most (84%) golfers consumed alcohol, averaging 7.91 servings/week. Golf participation, including days/week, holes/week, and practice hours/week, was not associated with alcohol use. Golfers with stronger social motives were 60% more likely to consume alcohol. Weekly walking (incident risk ratio (IRR) = 7.30), moderate-to-vigorous PA (MVPA; IRR = 5.04), and total PA (IRR = 4.14) were associated with more alcohol servings/week. Golfers’ alcohol use may be higher than the general adult population in the U.S. and contributes 775 extra kilocalories/week, a surplus that may offset PA-related energy expenditure and cancer-protective effects. Alcohol use interventions targeting golfers may facilitate weight loss and reduce cancer risk, especially for golfers motivated by social status. 相似文献
23.
W K Scott M A Nance R L Watts J P Hubble W C Koller K Lyons R Pahwa M B Stern A Colcher B C Hiner J Jankovic W G Ondo F H Allen C G Goetz G W Small D Masterman F Mastaglia N G Laing J M Stajich B Slotterbeck M W Booze R C Ribble E Rampersaud S G West R A Gibson L T Middleton A D Roses J L Haines B L Scott J M Vance M A Pericak-Vance 《JAMA》2001,286(18):2239-2244
CONTEXT: The relative contribution of genes vs environment in idiopathic Parkinson disease (PD) is controversial. Although genetic studies have identified 2 genes in which mutations cause rare single-gene variants of PD and observational studies have suggested a genetic component, twin studies have suggested that little genetic contribution exists in the common forms of PD. OBJECTIVE: To identify genetic risk factors for idiopathic PD. DESIGN, SETTING, AND PARTICIPANTS: Genetic linkage study conducted 1995-2000 in which a complete genomic screen (n = 344 markers) was performed in 174 families with multiple individuals diagnosed as having idiopathic PD, identified through probands in 13 clinic populations in the continental United States and Australia. A total of 870 family members were studied: 378 diagnosed as having PD, 379 unaffected by PD, and 113 with unclear status. MAIN OUTCOME MEASURES: Logarithm of odds (lod) scores generated from parametric and nonparametric genetic linkage analysis. RESULTS: Two-point parametric maximum parametric lod score (MLOD) and multipoint nonparametric lod score (LOD) linkage analysis detected significant evidence for linkage to 5 distinct chromosomal regions: chromosome 6 in the parkin gene (MLOD = 5.07; LOD = 5.47) in families with at least 1 individual with PD onset at younger than 40 years, chromosomes 17q (MLOD = 2.28; LOD = 2.62), 8p (MLOD = 2.01; LOD = 2.22), and 5q (MLOD = 2.39; LOD = 1.50) overall and in families with late-onset PD, and chromosome 9q (MLOD = 1.52; LOD = 2.59) in families with both levodopa-responsive and levodopa-nonresponsive patients. CONCLUSIONS: Our data suggest that the parkin gene is important in early-onset PD and that multiple genetic factors may be important in the development of idiopathic late-onset PD. 相似文献
24.
Association of single-nucleotide polymorphisms of the tau gene with late-onset Parkinson disease. 总被引:14,自引:1,他引:13
E R Martin W K Scott M A Nance R L Watts J P Hubble W C Koller K Lyons R Pahwa M B Stern A Colcher B C Hiner J Jankovic W G Ondo F H Allen C G Goetz G W Small D Masterman F Mastaglia N G Laing J M Stajich R C Ribble M W Booze A Rogala M A Hauser F Zhang R A Gibson L T Middleton A D Roses J L Haines B L Scott M A Pericak-Vance J M Vance 《JAMA》2001,286(18):2245-2250
CONTEXT: The human tau gene, which promotes assembly of neuronal microtubules, has been associated with several rare neurologic diseases that clinically include parkinsonian features. We recently observed linkage in idiopathic Parkinson disease (PD) to a region on chromosome 17q21 that contains the tau gene. These factors make tau a good candidate for investigation as a susceptibility gene for idiopathic PD, the most common form of the disease. OBJECTIVE: To investigate whether the tau gene is involved in idiopathic PD. DESIGN, SETTING, AND PARTICIPANTS: Among a sample of 1056 individuals from 235 families selected from 13 clinical centers in the United States and Australia and from a family ascertainment core center, we tested 5 single-nucleotide polymorphisms (SNPs) within the tau gene for association with PD, using family-based tests of association. Both affected (n = 426) and unaffected (n = 579) family members were included; 51 individuals had unclear PD status. Analyses were conducted to test individual SNPs and SNP haplotypes within the tau gene. MAIN OUTCOME MEASURE: Family-based tests of association, calculated using asymptotic distributions. RESULTS: Analysis of association between the SNPs and PD yielded significant evidence of association for 3 of the 5 SNPs tested: SNP 3, P =.03; SNP 9i, P =.04; and SNP 11, P =.04. The 2 other SNPs did not show evidence of significant association (SNP 9ii, P =.11, and SNP 9iii, P =.87). Strong evidence of association was found with haplotype analysis, with a positive association with one haplotype (P =.009) and a negative association with another haplotype (P =.007). Substantial linkage disequilibrium (P<.001) was detected between 4 of the 5 SNPs (SNPs 3, 9i, 9ii, and 11). CONCLUSIONS: This integrated approach of genetic linkage and positional association analyses implicates tau as a susceptibility gene for idiopathic PD. 相似文献
25.
Olasveengen Theresa M. Semeraro Federico Ristagno Giuseppe Castren Maaret Handley Anthony Kuzovlev Artem Monsieurs Koenraad G. Raffay Violetta Smyth Michael Soar Jasmeet Svavarsdóttir Hildigunnur Perkins Gavin D. 《Notfall & Rettungsmedizin》2021,24(4):386-405
Notfall + Rettungsmedizin - Der Europäische Rat für Wiederbelebung hat diese Leitlinie – Basismaßnahmen zur Wiederbelebung – auf Grundlage des... 相似文献
26.
McPhate Lucy Williams Katrina Vance Alasdair Winther Jo Pang Kenneth May Tamara 《Archives of sexual behavior》2021,50(3):863-871
Archives of Sexual Behavior - Gender variance is a broad term used to describe gender non-conforming behaviors. Past studies have used the parental response to Child Behavior Checklist (CBCL) Item... 相似文献
27.
J. M. Vance M. A. Pericak-Vance R. C. Elston P. M. Conneally K. K. Namboodiri R. S. Wappner P. L. Yu John M. Optiz 《American journal of medical genetics. Part A》1980,7(2):131-140
Serum and/or plasma samples from 360 Whites and 126 Blacks were assayed for activity of the lysosomal hydrolase α-N-acetyl-D-glucosaminidase (NAG). The samples from the Blacks had an increased mean (0.50 nm/ml/min) and standard deviation (0.30 nm/ml/min) compared to those from the Whites (0.29 nm/ml/min and 0.10 nm/ml/min, respectively). After loge transformation and admixture analysis, it was possible to demonstrate the presence of 3 distributions of NAG activity in Blacks and at least 2 in Whites. Segregation analysis of the NAG activity of 29 White half-sib twin families indicated that a genetic model for the inheritance of NAG activity provided a better fit (P < 0.01) with the data than the “environmental” model. Thus, the study suggests the presence of a genetic polymorphism for NAG activity in Black and White populations. The presence of alleles for high and low NAG activity in the normal population could lead to incorrect interpretation of serum carrier tests for Sanfilippo syndrome, type B. 相似文献
28.
Njung'e K Critchley MA Handley SL 《Journal of psychopharmacology (Oxford, England)》1993,7(2):173-180
Effects of β-adrenoceptor agonists and antagonists have been examined on open/total arm entry ratio (OTR) over a wide range of doses in the rat elevated X-maze 'anxiety' model. For clenbuterol, terbutaline and adrenaline, OTR was reduced only at doses at or above those reducing total entries; dobutamine was inactive. Neither the β(1)-adrenoceptor antagonist metoprolol nor the β( 2)-adrenoceptor antagonist ICI 118,551 affected OTR or total entries. The peripherally acting β(1)-antagonist practolol was also inactive. The elevated X-maze therefore does not appear to detect β-adrenoceptor-mediated changes in 'anxiety'. Among the β-adrenoceptor antagonists which also bind to 5-HT(1) receptors, sotalol and timolol were inactive but restricted doses of alprenolol (0.1 mg/kg) and pindolol (0.1-0.25 mg/kg) caused an anxiolytic-like increase in OTR while propranolol (5-10 mg/kg) and pindolol (1.0 mg/kg) reduced OTR without affecting total entries. These effects may be attributable to the activity of these agents at 5-HT( 1) receptors. Since metoprolol (3.0 mg/kg) and ICI 118,551 (1.0 mg/kg) did not alter the fall in OTR caused by the selective 5-HT(1A) agonist 8-OH-DPAT, the antagonism of this fall by alprenolol (0.5 mg/kg), pindolol (0.5 mg/kg), propranolol (3.0 mg/kg) and timolol (3.0 mg/kg) is most likely to represent a 5-HT(1) receptor antagonist effect of these agents. 相似文献
29.
RX336-M (7,8-dihydro-5',6'-dimethylcyclohex-5'-eno-1',2',8',14 codeinone) induced a complex of simultaneous rapid movements of body parts accompanied by a single squeak-vocalization, which occurred at irregular intervals, when injected i.p. in mice. The complex included whole body jerks and head-shakes and its frequency was dose dependent between 0.1 and 20 mg/kg. Frequency after a 5 mg/kg dose was reduced by haloperidol (0.5-10 mg/kg, i.p.), ritanserin (0.1-10 mg/kg, i.p.) and ICI 169,369 (2.0 mg/kg, i.p.), suggesting the possible involvement of 5-HT(2A) and/or dopamine receptors. The possible relevance of the behavioural effects of RX336-M to the tics and vocalization of Tourette's syndrome is discussed. 相似文献
30.
Effects of water deprivation and restraint were compared in the rat elevated X-maze. Water deprivation for 12–48 h increased corticosterone and had a duration-dependent anxiolytic effect in the elevated X-maze, increasing the ratio of open/total arm entries (OTR) and the proportion of time spent on the open arms (% time) without affecting total entries. Brain 5HIAA/5HT was increased only after 24 or 48 h deprivation. Restraint for 15 min also increased plasma corticosterone and brain 5HIAA/5HT but had no effect on behaviour in the elevated X-maze when rats were tested immediately afterwards. However, 1 h restraint was anxiogenic in the elevated X-maze immediately after release, reducing OTR and % time, but with a less consistent reduction in total entries; reductions in OTR and % time were still present 24 h later. The 5HT1A agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) (0.1–0.2 mg/kg), administered 10 min before testing in the elevated X-maze, had anxiogenic actions in non-stressed rats. The effect of 0.1 mg/kg 8-OH-DPAT was not significantly altered by 24 or 48 h water deprivation but was abolished by restraint for 1 h immediately beforehand, despite the anxiogenic effect of restraint alone. Similar mutual antagonism of 8-OH-DPAT and restraint occurred when the dose of 8-OH-DPAT was increased to 0.2 mg/kg. Twenty-four hours after restraint, restrained rats which had received 8-OH-DPAT (0.1–0.2 mg/kg) still did not show any significant anxiogenic effect compared with non-restrained vehicle treated controls. Restraint-induced deficits in elevated X-maze exploration may prove a useful model with which to study the pharmacology of depression-related anxiety. However, the effects of the stressors examined, and their interaction with 8-OH-DPAT in the elevated X-maze, appear to depend on the nature of the stressor. 相似文献