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排序方式: 共有1407条查询结果,搜索用时 921 毫秒
91.
Saresella M Marventano I Speciale L Ruzzante S Trabattoni D Della Bella S Filippi M Fasano F Cavarretta R Caputo D Clerici M Ferrante P 《Journal of neuroimmunology》2005,166(1-2):173-179
We investigated the apoptosis of myelin basic protein (MBP)-specific T lymphocytes in multiple sclerosis (MS) patients with acute (AMS) or stable (SMS) MS by evaluating the expression of apoptosis markers on peripheral cells. Cells of healthy controls (HC) were evaluated as well. Results showed that mitogen-stimulated apoptosis was comparable among patients and controls, whereas MBP-stimulated CD4+ and CD8+ 7-AAD+ and 7-AAD+ Fas+ cell (apoptotic cells) were significantly reduced in AMS patients. A reduction of the apoptotic rate of myelin-specific CD4+ and CD8+ T lymphocytes could be involved in the immune-mediated destruction of the myelin sheath seen in AMS patients. 相似文献
92.
D'Arrigo S Viganò L Grazia Bruzzone M Marzaroli M Nikas I Riva D Pantaleoni C 《Journal of child neurology》2005,20(11):859-866
We reviewed the clinical records of 51 extensively investigated pediatric patients with structural abnormalities of the cerebellum as revealed by magnetic resonance imaging (MRI). Ten had hypoplasia of the vermis, 21 had hypoplasia of the vermis and cerebellar hemispheres, 2 had pontocerebellar hypoplasia, and 18 had progressive cerebellar atrophy. A clear diagnosis was reached in 37 (72.5%). Initial characterization of the cerebellar alterations by MRI separated hypoplastic from atrophic cases and confirmed MRI as an essential preliminary means for distinguishing malformations from metabolic-degenerative conditions. However, the diagnostic possibilities are so numerous that it is not feasible to propose a standardized diagnostic protocol for pediatric patients with an altered cerebellum. Subsequent investigations should be suggested by the neuroradiologic and clinical peculiarities of each case. 相似文献
93.
Castellucci P Nanni C Farsad M Alinari L Zinzani P Stefoni V Battista G Valentini D Pettinato C Marengo M Boschi S Canini R Baccarani M Monetti N Franchi R Rampin L Fanti S Rubello D 《Nuclear medicine communications》2005,26(8):689-694
OBJECTIVE: To evaluate the prevalence and scan interpretation criteria useful in identifying non-tumoural F-FDG focal uptakes (potential pitfalls) in patients who had been previously treated for a malignant lymphoma studied by positron emission tomography (PET). MATERIALS: Nine hundred and ninety-six consecutive PET scans obtained in 706 patients with malignant lymphoma were reviewed. All patients had been previously treated by first-line chemo-radiotherapy, plus surgery when required, and were then studied by FDG PET to investigate suspected recurrence at doubtful or inconclusive conventional radiological imaging (ultrasound, computed tomography, magnetic resonance imaging). PET was obtained with patients in the fasted condition and after i.v. injection of 370 MBq of F-FDG; imaging was acquired 60-90 min later. In patients with focal FDG uptake the final diagnosis was reached on the basis of histological findings or long-term follow-up. RESULTS: Thirty-one of 134 PET scans (23.1%) showing focal FDG uptake were diagnosed as non-tumoural radiotracer uptake, related to the presence of brown fat in seven cases, thymic hyperplasia in five, muscles contraction in four, lymph node unspecific inflammation in four, mediastinal/pulmonary unspecific inflammation in four, gastritis in two, colitis in two, bacterial abscess in one, lactating breast in one, and herpes zoster in one. Each of the above cited situations has been reported in the literature, generally in the form of sporadic reports, as a potential cause of misinterpretation (false positive) in reading a PET scan with the potential for incorrect patient management. An accurate diagnosis in these patients was important for the following therapeutic decision making. CONCLUSIONS: In the whole series of patients with treated malignant lymphoma, the prevalence of non-tumoural FDG focal uptake during follow-up was relatively low (3.1%); conversely, it was relatively high when considering the sub-group of 'positive' PET only (23.1%). The importance of knowing these situations in order to avoid misinterpretation in reading PET scans needs to be emphasized. In this light, an accurate patient's history and a skilful nuclear medicine physician are very important factors. For the same purpose, it is reasonable to think that the use of hybrid PET/CT tomographs could also play an important role in helping to identify non-tumoural FDG focal uptake. 相似文献
94.
95.
Isolation, structure, absolute stereochemistry, and HIV-1 integrase inhibitory activity of integrasone, a novel fungal polyketide 总被引:2,自引:0,他引:2
Herath KB Jayasuriya H Bills GF Polishook JD Dombrowski AW Guan Z Felock PJ Hazuda DJ Singh SB 《Journal of natural products》2004,67(5):872-874
HIV-1 integrase is a critical enzyme for replication of HIV, and its inhibition is one of the most promising new drug targets for anti-retroviral therapy with potentially significant advantages over existing therapies. In this Note, the isolation, structure elucidation, and absolute stereochemistry of integrasone, a novel polyketide, derived from an unidentified sterile mycelium have been described. This bicyclic dihydroxy epoxide lactone inhibited the strand transfer reaction of HIV-1 integrase with an IC(50) of 41 microM. 相似文献
96.
Xu L Krenitsky DM Seacat AM Butenhoff JL Anders MW 《Chemical research in toxicology》2004,17(6):767-775
Perfluorooctanesulfonic acid (PFOS) and its derivatives have been used in a range of industrial and commercial applications, including the manufacture of surfactants, adhesives, anticorrosion agents, and insecticides. PFOS is found at detectable concentrations in human and wildlife tissues and in the global environment. N-Substituted perfluorooctanesulfonamides are believed to be degraded to PFOS and, therefore, contribute to the accumulation of PFOS in the environment. N-Ethyl-N-(2-hydroxyethyl)perfluorooctanesulfonamide (N-EtFOSE) is converted to PFOS in experimental animals. The objective of this study was to elucidate the pathways for the biotransformation of N-EtFOSE, which is a major precursor and component of PFOS-based compounds. N-EtFOSE and several putative metabolites were incubated with liver microsomes and cytosol and with liver slices from male Sprague-Dawley rats. Microsomal fractions fortified with NADPH catalyzed the N-deethylation of N-EtFOSE to give N-(2-hydroxyethyl)perfluorooctanesulfonamide (FOSE alcohol) and of FOSE alcohol to give perfluorooctanesulfonamide (FOSA). These N-dealkylation reactions were catalyzed mainly by male rat P450 2C11 and P450 3A2 and by human P450 2C19 and 3A4/5. Rat liver microsomal fractions incubated with UDP-glucuronic acid catalyzed the O-glucuronidation of N-EtFOSE and FOSE alcohol and the N-glucuronidation of FOSA. Cytosolic fractions incubated with NAD(+) catalyzed the oxidation of FOSE alcohol to perfluooctanesulfonamidoacetate (FOSAA). The oxidation of N-EtFOSE to N-ethylperfluorooctanesulfonamidoacetate (N-EtFOSAA) was observed in liver slices but not in cytosolic fractions. FOSA was biotransformed in liver slices to PFOS, albeit at a low rate. These results show that the major pathway for the biotransformation of N-EtFOSE is N-dealkylation to give FOSA. The biotransformation of FOSA to PFOS explains the observation that PFOS is found in animals given N-EtFOSE. 相似文献
97.
Barone MA Johnson CH Luick MA Teutonico DL Magnani RJ 《Perspectives on sexual and reproductive health》2004,36(1):27-33
CONTEXT: Even though vasectomy is a popular method of contraception in the United States, there is limited information on the characteristics of men choosing vasectomy and why they decide to undergo the procedure.
METHODS: A nationwide, practice-based survey of 719 men receiving vasectomies was conducted between July 1998 and June 1999.
RESULTS: Low-income, minority and less educated men were underrepresented among vasectomy recipients. The majority of men were married or cohabiting (91%), non-Hispanic and white (87%), and educated beyond high school (81%). Only 7% of men had annual household incomes of less than $25,000, and fewer than 1% paid for the procedure using public funding; 81% of respondents paid through private insurance or a health maintenance organization. Half of men reported choosing vasectomy over a reversible method because it is the most secure means of preventing pregnancy, and 62% chose vasectomy over tubal ligation because the procedure is simpler and safer. Doctors and nurses were the most important sources of information about vasectomy (cited by 31% of respondents), followed by wives or partners (25%) and friends (23%).
CONCLUSIONS: Despite the diversity of the U.S. population, vasectomy recipients are a homogeneous group. By identifying users of vasectomy and underserved groups, our findings should assist service providers and program managers in planning strategies to reduce the large difference in levels of vasectomy use among men of different races, ethnicities and income groups. 相似文献
METHODS: A nationwide, practice-based survey of 719 men receiving vasectomies was conducted between July 1998 and June 1999.
RESULTS: Low-income, minority and less educated men were underrepresented among vasectomy recipients. The majority of men were married or cohabiting (91%), non-Hispanic and white (87%), and educated beyond high school (81%). Only 7% of men had annual household incomes of less than $25,000, and fewer than 1% paid for the procedure using public funding; 81% of respondents paid through private insurance or a health maintenance organization. Half of men reported choosing vasectomy over a reversible method because it is the most secure means of preventing pregnancy, and 62% chose vasectomy over tubal ligation because the procedure is simpler and safer. Doctors and nurses were the most important sources of information about vasectomy (cited by 31% of respondents), followed by wives or partners (25%) and friends (23%).
CONCLUSIONS: Despite the diversity of the U.S. population, vasectomy recipients are a homogeneous group. By identifying users of vasectomy and underserved groups, our findings should assist service providers and program managers in planning strategies to reduce the large difference in levels of vasectomy use among men of different races, ethnicities and income groups. 相似文献
98.
Isozyme-specific abnormalities of PKC in thyroid cancer: evidence for post-transcriptional changes in PKC epsilon 总被引:5,自引:0,他引:5
99.
Gai M Motta D Cantaluppi V Fop F Jeantet A Segoloni GP Piccoli GB Lanfranco G 《Kidney international》2003,64(6):2326-7; author reply 2327
100.
Dibenzylphosphorobenzyl and phosphorobenzyl analogues of isophosphoramide mustard, an active metabolite of ifosfamide were synthesized. Phosphorobenzyl analogue posseses stronger cytotoxic activity than isophosphoroamide mustard against the cells of several cancer cell lines suggesting the possibility of the use of this compound in Gene-Directed Enzyme-Prodrug Therapy (GDEPT). 相似文献