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61.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml-1诱导HL-60细胞发生凋亡,而阻断HR20细胞于G1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml-1处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关。 相似文献
62.
Complications of spinal cord arteriography: prospective assessment of risk for diagnostic procedures
Forbes G; Nichols DA; Jack CR Jr; Ilstrup DM; Kispert DB; Piepgras DG; Wiebers DO; Earnest F th; Axley PL 《Radiology》1988,169(2):479-484
A prospective study was done of complications associated with 134 consecutive diagnostic spinal cord arteriograms in 96 patients (63 men and 33 women aged 17-78 years). Patients were examined for either arteriovenous malformation (n = 88) or tumor (n = 8), as indicated by myelography. Among the complications, 11 (8.2%) were local, five (3.7%) were systemic nonneurologic, and three (2.2%) were neurologic (two were associated with full recovery in less than 24 hours, and one was associated with full recovery in less than 1 week). No specific clinical or technical factors were significantly associated with the development of neurologic complications. Details of the clinical profile, angiographic technique, and pathologic findings for each patient were recorded and analyzed with respect to the potential risk for arteriographic complications. Diagnostic spinal cord arteriography had an acceptable risk within the range of other neuroangiographic diagnostic procedures. 相似文献
63.
64.
A scanning equalization system for improved chest radiography 总被引:1,自引:0,他引:1
65.
Michela Faggioni Usman Baber Jaya Chandrasekhar Samantha Sartori William Weintraub Sunil V. Rao Birgit Vogel Bimmer Claessen Annapoorna Kini Mark Effron Zhen Ge Stuart Keller Craig Strauss Clayton Snyder Catalin Toma Sandra Weiss Melissa Aquino Brian Baker Anthony Defranco Sameer Bansilal Brent Muhlestein Samir Kapadia Stuart Pocock Kanhaiya L. Poddar Timothy D. Henry Roxana Mehran 《Catheterization and cardiovascular interventions》2019,94(1):53-60
66.
E Waanders H Venselaar RHM Te Morsche DB De Koning PS Kamath VE Torres S Somlo JPH Drenth 《Clinical genetics》2010,78(1):47-56
Waanders E, Venselaar H, te Morsche RHM, de Koning DB, Kamath PS, Torres VE, Somlo S, Drenth JPH. Secondary and tertiary structure modeling reveals effects of novel mutations in polycystic liver disease genes PRKCSH and SEC63. Polycystic liver disease (PCLD) is characterized by intralobular bile duct cysts in the liver. It is caused by mutations in PRKCSH, encoding hepatocystin, and SEC63, encoding Sec63p. The main goals of this study were to screen for novel mutations and to analyze mutations for effects on protein structure and function. We screened 464 subjects including 76 probands by direct sequencing or conformation‐sensitive capillary electrophoresis. We analyzed the effects of all known and novel mutations using a combination of splice site recognition, evolutionary conservation, secondary and tertiary structure predictions, Poly Phen , and p Mut and sift . We identified a total of 26 novel mutations in PRKCSH (n = 14) and SEC63 (n = 12), including four splice site mutations, eight insertions/ deletions, six non‐sense mutations, and eight missense mutations. Out of 48 PCLD mutations, 13 were predicted to affect splicing. Most mutations were located in highly conserved regions and homology modeling for two domains of Sec63p showed severe effects of the residue substitutions. In conclusion, we identified 26 novel mutations associated with PCLD and we provide in silico analysis in order to delineate the role of these mutations. 相似文献
67.
T.V. Parran C.A. Adelman B. Merkin M.E. Pagano R. Defranco R.A. Ionescu A.G. Mace 《Drug and alcohol dependence》2010
Background
Buprenorphine/naloxone was approved by the FDA for office-based opioid maintenance therapy (OMT), with little long-term follow-up data from actual office-based practice. 18-Month outcome data on the office-based use of buprenorphine/naloxone (bup/nx) and the impact of socioeconomic status and other patient characteristics on the duration and clinical effects of bup/nx are reported.Methods
This retrospective chart review and cross-sectional telephone interview provide treatment retention of opioid-dependent patients receiving bup/nx-OMT in an office-based setting. 176 opioid-dependent patients from two different socioeconomic groups (high and low SES) were begun on bup/nx, started intensive outpatient treatment, and followed-up after a minimum of 18 months (18–42 months) by telephone interview to assess treatment outcome.Results
110 subjects (67%) completed the interview, 77% remained on bup/nx with no difference in retention between high and low SES groups. Those on bup/nx at follow-up were more likely to report abstinence, to be affiliated with 12-step recovery, to be employed and to have improved functional status.Conclusions
Bup/nx-OMT is a viable treatment option and when coupled with a required abstinence oriented addiction counseling program is effective in promoting abstinence, self-help group attendance, occupational stability, and improved psychosocial outcomes in both low SES and high SES patient populations over an 18–42-month period. 相似文献68.
Christina J. Valentine Aiman Q. Khan Alexandra R. Brown Scott A. Sands Emily A. Defranco Byron J. Gajewski Susan E. Carlson Kristina M. Reber Lynette K. Rogers 《Nutrients》2021,13(12)
Pregnancy and parturition involve extensive changes in the maternal immune system. In our randomized, multi-site, double-blind superiority trial using a Bayesian adaptive design, we demonstrated that 1000 mg/day of docosahexaenoic acid (DHA) was superior to 200 mg/day in preventing both early preterm birth (less than 34 weeks’ gestation) and preterm birth (less than 37 weeks’ gestation). The goal of this secondary study is to compare the effects of 1000 mg/day versus 200 mg/day on maternal inflammation, a possible mechanism by which DHA may prevent preterm birth. Maternal blood samples were collected at enrollment (12–20 weeks’ gestation) and at delivery. Red blood cell DHA levels were measured by gas chromatography, and plasma concentrations of sRAGE, IL-6, IL-1β, TNFα, and INFγ were measured by ELISA. Data were analyzed for associations with the DHA dose, gestational age at birth, and preterm birth (<37 weeks). Higher baseline and lower delivery levels of maternal sRAGE were associated with a greater probability of longer gestation and delivery at term gestation. Higher-dose DHA supplementation increased the probability of a smaller decrease in delivery sRAGE levels. Higher IL-6 concentrations at delivery were associated with the probability of delivering after 37 weeks, and higher-dose DHA supplementation increased the probability of greater increases in IL-6 concentrations between enrollment and delivery. These data provide a proposed mechanistic explanation of how a higher dose of DHA during pregnancy provides immunomodulatory regulation in the initiation of parturition by influencing sRAGE and IL-6 levels, which may explain its ability to reduce the risk of preterm birth. 相似文献
69.
70.
KJ Champion C Bunag AL Estep JR Jones CH Bolt RC Rogers KA Rauen DB Everman 《Clinical genetics》2011,79(5):468-474
Champion KJ, Bunag C, Estep AL, Jones JR, Bolt CH, Rogers RC, Rauen KA, Everman DB. Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome. BRAF, the protein product of BRAF, is a serine/threonine protein kinase and one of the direct downstream effectors of Ras. Somatic mutations in BRAF occur in numerous human cancers, whereas germline BRAF mutations cause cardio‐facio‐cutaneous (CFC) syndrome. One recurrent somatic mutation, p.V600E, is frequently found in several tumor types, such as melanoma, papillary thyroid carcinoma, colon cancer, and ovarian cancer. However, a germline mutation affecting codon 600 has never been described. Here, we present a patient with CFC syndrome and a de novo germline mutation involving codon 600 of BRAF, thus providing the first evidence that a pathogenic germline mutation involving this critical codon is not only compatible with development but can also cause the CFC phenotype. In vitro functional analysis shows that this mutation, which replaces a valine with a glycine at codon 600 (p.V600G), leads to increased ERK and ELK phosphorylation compared to wild‐type BRAF but is less strongly activating than the cancer‐associated p.V600E mutation. 相似文献