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排序方式: 共有255条查询结果,搜索用时 10 毫秒
31.
Shiramizu B Paul R Williams A Shikuma C Watters M Grove J Valcour V 《The Journal of neuropsychiatry and clinical neurosciences》2007,19(2):157-163
The authors previously found a strong association between elevated HIV proviral DNA (HIV DNA) and a diagnosis of HIV-1-associated dementia (HAD) vs. normal cognition. It is unclear whether HIV DNA globally affects the diagnosis of HAD or whether the effect is limited to individual neuropsychological deficits. This exploratory study examined baseline HIV DNA and its association with individual neuropsychological deficits. HIV DNA was significantly associated with baseline neuropsychological deficits independent of age, ethnicity, IQ, and plasma HIV-1 RNA levels. However, HIV DNA did not predict future changes in neuropsychological deficits. The data suggest that HIV DNA and neuropsychological deficits may co-vary over time. 相似文献
32.
Z Luo Y Chen S Chen WJ Welch BT Andresen PA Jose CS Wilcox 《British journal of pharmacology》2009,157(6):935-943
Background and purpose:
We compared the dose-dependent reductions in cellular superoxide anion (O2−) by catalytic agents: superoxide dismutase (SOD), polyethylene glycol (PEG)-SOD and the nitroxide 4-hydroxy-2,2,6,6,-tetramethylpiperidine-1-oxyl (tempol) with uncharacterized antioxidants: 5,10,15,20-tetrakis (4-sulphonatophenyl) porphyrinate iron (III)(Fe-TTPS), (-)-cis-3,3′,4′,5,7-pentahydroxyflavane (2R,3R)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-1(2H)-benzopyran-3,5,7-triol (-epicatechin), 2-phenyl-1,2-benzisoselenazol-3(2H)-one (ebselen) and N-acetyl-L-cysteine (NAC) with the spin trap nitroblue tetrazolium (NBT) and with the vitamins or their analogues: ascorbate, α-tocopherol and 6-hydroxy-2,5,7,8-tetramethylkroman-2-carboxy acid (trolox).Experimental approach:
O2− was generated in primary cultures of angiotensin II-stimulated preglomerular vascular smooth muscle cells from spontaneously hypertensive rats and detected by lucigenin-enhanced chemiluminescence.Key results:
SOD, PEG-SOD, NAC and tempol produced a similar maximum inhibition of O2− of 80–90%. -Epicatechin, NBT, ebselen and Fe-TTPS were significantly (P < 0.0125) less effective (50–70%), whereas trolox, α-tocopherol and ascorbate had little action even over 24 h of incubation (<31%). Effectiveness in disrupted and intact cells was similar for the permeable agents, PEG-SOD and tempol, but was enhanced for SOD. Generation of O2− was increased by NAC and NBT at low concentrations but reduced at high concentrations.Conclusions and implications:
Maximum effectiveness against cellular production of O2− requires cell membrane permeability and catalytic action as exemplified by PEG-SOD or tempol. NAC and NBT have biphasic effects on O2− production. Vitamins C and E or analogues have low efficacy. 相似文献33.
Ratto-Kim S Chuenchitra T Pulliam L Paris R Sukwit S Gongwon S Sithinamsuwan P Nidhinandana S Thitivichianlert S Shiramizu BT de Souza MS Chitpatima ST Sun B Rempel H Nitayaphan S Williams K Kim JH Shikuma CM Valcour VG;Southeast Asia Research Collaboration with the University of Hawaii 《Journal of neuroimmunology》2008,195(1-2):100-107
HIV Associated Dementia (HAD) is a complication of HIV infection in developed countries and is still poorly defined in resource-limited settings. In this study we investigated the expression of the monocyte phenotype CD14CD16HLADR and the inflammatory profiles in monocytes supernatants by surface-enhanced laser desorption/ionization-time of flight (SELDI-TOF) mass spectrometry in a cohort of HAD and non-HAD Thai volunteers prior to the initiation of ARV. The CD14CD16HLADR phenotype was significantly increased in monocytes from HAD and non-HAD versus negative controls, but there was no difference in phenotype and in the secretion protein profiles between the two seropositive groups. In addition, monocytes supernatants from HAD and non-HAD did not induced apoptosis or cell death in brain aggregate culture. In conclusion it appears that HAD in Thai individuals has a different immunological profile then in North America cohorts. 相似文献
34.
35.
Rudge C Johnson RJ Fuggle SV Forsythe JL;Kidney Pancreas Advisory Group UK Transplant NHS BT 《Transplantation》2007,83(9):1169-1173
BACKGROUND: To investigate any differences in access to transplant and post-transplant outcomes for ethnic minority patients in the United Kingdom, national data on ethnicity of patients on the waiting list, those receiving a transplant, and deceased donors were analyzed. METHODS: Adult patients and donors were included. Ethnic origin was classified as white, Asian, black, or "other." National data were analyzed, and 2001 U.K. National census data were used for comparative purposes. Median waiting times to transplant were obtained from Kaplan-Meier estimates for patients registered 1998-2000. Transplant survival was estimated for patients transplanted from 1998 to 2003. RESULTS: A total of 92% of the U.K. population was white, compared with 77% of waiting list patients, 88% of transplant recipients, and 97% of deceased donors. Median waiting time to transplantation for white patients was 719 days (95% confidence interval 680-758) compared with 1368 (1131-1605) days for Asian patients and 1419 (1165-1673) days for black patients. The degree of human leukocyte antigen matching achieved was inferior for Asian and black patients. There is some evidence of inferior 3-year transplant survival for black patients compared with white and Asian patients (P=0.03). CONCLUSIONS: There are imbalances in the ethnic make up of the waiting list, the donor pool, and renal transplant recipients. There are significant differences in both post-transplant outcomes and time to transplantation between patients of different ethnic origin. Waiting times are influenced by allocation schemes, and the 2006 U.K. National Kidney Allocation Scheme is designed to achieve greater equity of access to transplant for all patients, regardless of geography, blood group, or ethnicity. 相似文献
36.
37.
In immunocompromised patients, cytomegalovirus myocarditis leading to dilated cardiomyopathy is rare, and the duration of myocardial damage in such patients has not yet been determined. We report here one renal transplant recipient with cytomegalovirus myocarditis. This case shows that the myocardial damage secondary to cytomegalovirus may be insidious and persist for a relatively long period in the immunocompromised patient. 相似文献
38.
Biochemistry of the induction and prevention of lipoperoxidative damage in human spermatozoa 总被引:8,自引:1,他引:7
Lipid peroxidation occurs in human sperm cells with damage to the cell
plasma membrane, leading to loss of cytosolic components and hence to cell
'death'. The peroxidation may be induced at high rates in the presence of
Fe2+ and ascorbate. It occurs at slower rates under physiological
conditions as spontaneous lipid peroxidation, which has the following
characteristics. The rate is constant over the time required for complete
loss of motility in the cells of the sperm sample; one can thus use the
time to complete loss of motility (TLM) as a ready measure of the rate.
Loss of motility occurs at a characteristic extent of lipid peroxidation,
assayed in terms of production of the peroxidative breakdown product,
malonaldehyde (MA), that is independent of peroxidation rate. For human
sperm, this extent corresponds to 0.1 nmol MA/10(8) cells. Human
spermatozoa possess the anti-lipoperoxidative defence enzymes, superoxide
dismutase (SOD) and glutathione peroxidase plus glutathione reductase
(GPX/GRD). The SOD activity is highly variable between human sperm samples
while the activities of GPX and GRD are rather more constant. The rates of
production of superoxide anion, O2-, and hydrogen peroxide, H2O2, from
human spermatozoa are variable, but their sum calculated in O2- equivalents
as O2- + 2H2O2 is quite constant. The variability arises from the
variability in SOD activity: all H2O2 produced is from O2- due to the
action of SOD. The essential role of SOD as defence enzyme is inferred from
the observation that TLM of a given sperm sample is directly proportional
to the SOD activity of that sample. The essential role of GPX/GRD is
inferred from the observation that inhibition of GPX, either with
mercaptosuccinate or with complete oxidation of intracellular reduced
glutathione, results in a 20-fold increase in peroxidation rate. The
capacity of the GPX/GRD system appears to be limited by the
glucose-6-phosphate dehydrogenase-catalysed rate of production of NADPH,
the required reductive substrate for GRD. Human spermatozoa appear to have
enough anti-lipoperoxidative defensive capacity for lifetimes long enough
for fertilization but still short enough for ready removal from the female
reproductive tract in good time. Too low a defence capacity could lead to
male infertility.
相似文献
39.
A case of squamous cell carcinoma of the ureter with extension into the renal vein is presented. Immunoperoxidase method revealed positive staining for carcinoembryonic antigen. The literature on ureteral tumors is reviewed with special reference to renal vein involvement and carcinoembryonic antigen. 相似文献
40.
Pure leiomyoma of the prostate is a rare lesion. We report a case in a 68-year-old man who presented with rectal symptoms. Rectal examination showed a stony hard nodule with irregular surface near the apex of the prostate. Transrectal sonography showed a homogeneous well defined nodule measuring 3.5 cm in diameter in the left prostatic lobe protruding into the bladder. Magnetic resonance imaging (MRI) revealed an irregular shaped mass in the prostate with an isosignal to muscle in the T1 weighted images. Needle biopsy revealed pure leiomyoma histologically. Transurethral resection was performed and a nodule of white almost avascular tissue was resected in the apex proximal to vermontanum. After operation, the rectal symptoms improved. 相似文献