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排序方式: 共有137条查询结果,搜索用时 15 毫秒
1.
2.
The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed. 相似文献
3.
Baqar Husaini Aashrai SV. Gudlavalleti Van Cain Robert Levine Majaz Moonis 《Indian Journal of Community Medicine》2015,40(4):258-263
Aims:
To examine the variation in risk factors and hospitalization costs among four elderly dementia cohorts by race and gender.Materials and Methods:
The 2008 Tennessee Hospital Discharged database was examined. The prevalence, risk factors and cost of inpatient care of dementia were examined for individuals aged 65 years and above, across the four race gender cohorts - white males (WM), black males (BM), white females (WF), and black females (BF).Results:
3.6% of patients hospitalized in 2008 had dementia. Dementia was higher among females than males, and higher among blacks than whites. Further, BF had higher prevalence of dementia than WF; similarly, BM had a higher prevalence of dementia than WM. Overall, six risk factors were associated with dementia for the entire sample including HTN, DM, CKD, CHF, COPD, and stroke. These risk factors varied slightly in predicting dementia by race and gender. Hospital costs were 14% higher among dementia patients compared to non-dementia patients.Conclusions:
There exist significant race and gender disparities in prevalence of dementia. A greater degree of co-morbidity, increased duration of hospital stay, and more frequent hospitalizations, may result in a higher cost of inpatient dementia care. Aggressive management of risk factors may subsequently reduce stroke and cost of dementia care, especially in the black population. Race and gender dependent milestones for management of these risk factors should be considered. 相似文献4.
A sensitive and precise radioreceptor assay for determining plasma levels of human factor VIII/von Willebrand's factor (FVIII/vWF) has been developed by taking advantage of the FVIII/vWF receptor sites on human platelets. Paraformaldehyde-fixed platelets, which were processed and then stored, retained FVIII/vWF binding activity and therefore could be used as a convenient source of receptors. The human plasma samples to be tested were initially filtered on 4% agarose columns to concentrate the FVIII/vWF protein in the void volume and to remove the factor(s) that interferes with the assay. The percent recovery of FVIII/vWF in the pooled eluent was measured by the recovery of added trace 125I-FVIII/vWF. The coefficients of intra- and interassay variation were 6% and 10%, respectively. The plasma FVIII/vWF concentrations determined by the assay for pooled normal plasma, hemophilia A plasma, and plasmas from two patients with von Willebrand's disease were 16.3 +/- 0.5, 52.6 +/- 1.5, 6.8 +/- 0.8, and 3.2 +/- 0.2 microgram/ml, respectively. The range of plasma FVIII/vWF concentrations varied between 8.3 microgram/ml and 24.9 microgram/ml for 10 normal adults. The plasma FVIII/vWF concentrations determined by the radioreceptor assay correlated well with levels measured by the ristocetin-induced platelet aggregation method, thus demonstrating the functional relevancy of the radioreceptor assay for plasma FVIII/vWF. 相似文献
5.
目的探讨蜂胶对糖尿病伤口愈合的作用及其机制。方法采用荧光电泳法,检测不同葡萄糖浓度(5、25mmol/L)和不同蜂胶浓度(10、50、100、200μg/ml)处理的体外培养的人成纤维细胞及单核巨噬细胞系的基质金属蛋白酶MMP-9蛋白的表达。结果高浓度葡萄糖(25mmol/L)状态下,MMP-9表达增加,但与低浓度(5mmol/L)比较,差异无统计学意义。蜂胶可显著降低MMP-9的表达,并呈剂量依赖性(P〈.05)。结论高糖能增加单核巨噬细胞系及成纤维细胞MMP-9的表达,可能会影响糖尿病患者伤口的愈合。蜂胶可抑制这些细胞MMP-9的表达,有益于细胞基质的积聚,从而有益于糖尿病患者伤口的愈合。 相似文献
6.
Tessa Timmers Rik Ossenkoppele Denise Visser Hayel Tuncel Emma E Wolters Sander CJ Verfaillie Wiesje M van der Flier Ronald Boellaard Sandeep SV Golla Bart NM van Berckel 《Journal of cerebral blood flow and metabolism》2020,40(12):2464
The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods. 相似文献
7.
G Low GJ Irwin G Haddock SV Maroo 《Journal of Medical Imaging and Radiation Oncology》2006,50(3):249-251
The Currarino triad is a complex anomaly consisting of an anorectal malformation, a sacral bone defect and a presacral mass. It was first described in 1981 and since then, approximately 250 cases have been reported. Radiology has an important part to play in the diagnosis of this entity, as the imaging features are characteristic. We report a case of Currarino triad in an infant who presented with intractable constipation and discuss relevant MRI and plain radiography findings. 相似文献
8.
Molecular characterization of human factor XSan Antonio 总被引:1,自引:0,他引:1
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio. 相似文献
9.
Surgery remains the treatment of choice for massive and recurrent hemoptysis. In some instances, however, immediate surgical intervention is contraindicated. In these situations, bronchial artery embolization (BAE) has proved to be a successful definitive treatment for non-surgical candidates and a palliative therapy in patients requiring hemodynamic stabilization prior to surgery. The most serious complication of BAE is spinal cord ischemia. This relates directly to the potential anastomotic connections between the bronchial circulation and the anterior spinal artery. Somatosensory evoked potentials (SSEPs) have been used in the past to monitor spinal cord ischemia during procedures that threaten the vascularity of the spinal cord. The authors report two cases in which SSEPs were employed to monitor spinal cord ischemia during bronchial artery embolization. 相似文献
10.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献