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排序方式: 共有344条查询结果,搜索用时 15 毫秒
1.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
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Objective To investigate the clinical and pathological characteristics of pauci-immune crescent glomerulo~nephritis (PICGN) in Chinese patients. Methods During 13 years (1985-1998), 6400 patients underwent non-transplanting renal biopsy. Twenty-four patients were diagnosed as PICGN. All clinical and laboratory data of these patients were collected from the patients’ records and used for detailed analysis. The diagnosis is based on clinico-pathologic findings. Results Of the 24 patients, 16 were females and 8 were males, with median age of 33 years (ranged 10-76 years). Microscopic polyarteritis (MPA) (33.3%) and systemic vasculitis (8.3%) were the secondary diseases. The incidence of PICGN was 0.38% in renal biopsies and 22.9% in crescentic glomerulonephritis. Clinically, most patients (75.0%) showed rapidly progressive nephritis with enlarged kidneys. At onset, gross hematuria was noted in 58.3% of patients, hypertension in 45.8%, nephrotic syndrome in 41.7%, and oliguria in 25.0%. However, systemic symptoms were rare except for anemia. Pathologically, necrosis of glomerular capillaries (62.5%), infiltration of monocytes and neutrophil cells in glomeruli (66.7%), and vasculitis in the interstitium (53.3%) were observed. In addition, glomerulosclerosis was noted in 45.8%, severe tubular atrophy in 83.3% and interstitial fibrosis in 75.0%. Anti-neutrophil cytoplasmic antibodies (ANCAs) were positive in 52.2%. All patients except two received intensively immunosuppressive therapy. Sixteen patients were available for long-term follow up (median 29.8 months, range 8-92 months). Twelve of them had life-sustaining renal function, four had normal serum creatinine (<124?μmol/L) and only 4 patients were dialysis-dependent. Conclusion PICGN is not rare in China. Early diagnosis and administration of immunosuppressive therapy, particularly in patients with rapidly progressive glomerulonephritis (RPGN), are important for good prognosis. 相似文献
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Jiang WZ Jin NY Li ZJ Zhang LS Wang HW Zhang YJ Han WY 《第二军医大学学报》2006,27(4):434-434
To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting. 相似文献
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Demographic and Clinical Factors Associated With Nonsurgical Osteoarthritis Treatment Among Patients in Outpatient Clinics 下载免费PDF全文
Lauren M. Abbate Amy S. Jeffreys Cynthia J. Coffman Todd A. Schwartz Liubov Arbeeva Leigh F. Callahan Nicole A. Negbenebor Wendy M. Kohrt Robert S. Schwartz Ernest Vina Kelli D. Allen 《Arthritis care & research》2018,70(8):1141-1149
Objective
To identify patient demographic and clinical characteristics associated with osteoarthritis (OA) treatment use.Methods
This was a secondary data analysis of 3 clinical trials among patients with hip or knee OA conducted in Duke Primary Care practices, the Durham Veterans Affairs (VA) Health Care System, and the University of North Carolina–Chapel Hill (UNC). At baseline, participants reported sociodemographic characteristics, OA‐related pain and function, and OA treatment use, including oral analgesics, topical creams, joint injections, and physical therapy. Separate, multivariable logistic models (adjusted for clustering of clinics and providers for the Duke and VA cohorts) were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the associations between participant characteristics and each type of OA treatment.Results
Oral analgesic use was reported by 70–82% of participants across the 3 cohorts. Physical therapy, knee injections, and topical creams were used by 39–52%, 55–60%, and 25–39% of Duke, VA, and UNC participants, respectively. In multivariable models, worse pain, stiffness, and function, per 5‐unit increase, were associated with greater odds of using any oral analgesic for the cohorts from Duke (OR 1.18 [95% CI 1.08–1.28]) and UNC (OR 1.14 [95% CI 1.05–1.24]), but not for the VA cohort (OR 1.04 [95% CI 0.95–1.14]). For all 3 cohorts, nonwhites had higher odds of using topical creams compared to whites.Conclusion
Results suggest potential underutilization of therapies other than oral analgesics. Patient characteristics may affect OA treatment use, and understanding the relationship between these factors and OA treatment preferences may improve adherence to OA treatment guidelines. 相似文献8.
Alexander M. Kulminski Nalini Raghavachari Konstantin G. Arbeev Irina Culminskaya Liubov Arbeeva Deqing Wu Svetlana V. Ukraintseva Kaare Christensen Anatoliy I. Yashin 《Biogerontology》2016,17(5-6):893-905
The apolipoprotein E (apoE) is a classic example of a gene exhibiting pleiotropism. We examine potential pleiotropic associations of the apoE2 allele in three biodemographic cohorts of long-living individuals, offspring, and spouses from the Long Life Family Study, and intermediate mechanisms, which can link this allele with age-related phenotypes. We focused on age-related macular degeneration, bronchitis, asthma, pneumonia, stroke, creatinine, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, diseases of heart (HD), cancer, and survival. Our analysis detected favorable associations of the ε2 allele with lower LDL-C levels, lower risks of HD, and better survival. The ε2 allele was associated with LDL-C in each gender and biodemographic cohort, including long-living individuals, offspring, and spouses, resulting in highly significant association in the entire sample (β = ?7.1, p = 6.6 × 10?44). This allele was significantly associated with HD in long-living individuals and offspring (relative risk [RR] = 0.60, p = 3.1 × 10?6) but this association was not mediated by LDL-C. The protective effect on survival was specific for long-living women but it was not explained by LDL-C and HD in the adjusted model (RR = 0.70, p = 2.1 × 10?2). These results show that ε2 allele may favorably influence LDL-C, HD, and survival through three mechanisms. Two of them (HD- and survival-related) are pronounced in the long-living parents and their offspring; the survival-related mechanism is also sensitive to gender. The LDL-C-related mechanism appears to be independent of these factors. Insights into mechanisms linking ε2 allele with age-related phenotypes given biodemographic structure of the population studied may benefit translation of genetic discoveries to health care and personalized medicine. 相似文献
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Anisimov VN Arbeev KG Popovich IG Zabezhinksi MA Rosenfeld SV Piskunova TS Arbeeva LS Semenchenko AV Yashin AI 《Experimental gerontology》2004,39(3):305-319
There have been some observations that low body weight and a low level of some hormones (e.g. IGF-1) during the first half of life are predictors of longer life in mice. However, contradictions in the available data on the biomarkers of aging and predictors of longevity have shown that the research in these fields has become a controversial pursuit. In our study we addressed the following questions: (i) Can particular physiological parameters (body weight, food intake, estrus function, body temperature, incidence of chromosome aberrations in bone marrow cells) measured at the age of 3 and 12 months be a predictor of longevity and the rate of tumor development in five strains of mice? (ii) Can a heavy body weight at the age of 3 and 12 months be a predictor of longevity and high tumor risk in five strains of mice? Mice of five strains-CBA, SHR, SAMR, SAMP and transgenic HER-2/neu (FVB/N)-were under observation from the age of 2-3 months until natural death. Body weight and temperature, food consumption, and estrous cycle were longitudinally studied in all animals. Tumors discovered at autopsy were studied morphologically. We calculated the life span's parameters (mean, maximum, mortality rate, mortality rate doubling time) as well as their correlation with other parameters studied. The longest living CBA mice have the lowest body weight at the ages of 3 and 12 months, the lowest food consumption, body temperature, incidence of chromosome aberrations and spontaneous tumor incidence. In comparison with all other mouse strains they also have the latest disturbances in estrus function and highest body weight gain. The shortest living transgenic HER-2/neu mice have the lowest weight at the ages of 12 months, the lowest body weight gain, maximal body temperature, the most rapid disturbances in estrus function and the highest incidence of chromosome aberrations and tumor incidence in comparison to all other mouse strains. Our findings have shown that heavier body weight at the age of 12 months is a predictor of longevity in female CBA and SAMP mice but not in SHR, SAMR and HER-2/neu mice. Excessive body weight at the ages of 3 or 12 months is not a predictor of increased tumor risk in the strains studied. In general, the existence and direction of a significant correlation between body weight and life span depends upon the animals' age and genotype. 相似文献
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