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101.
Lee JU Shin J Song W Kim H Lee S Jang SJ Wong SC Edelberg JE Liau G Hong MK 《Coronary artery disease》2005,16(7):451-456
OBJECTIVES: We previously demonstrated that sphingosine kinase (SPK) increases the level of extracellular sphingosine-1-phosphate and promotes neovascularization in a mouse matrigel model. In this study, we tested the hypothesis that SPK gene transfer using a novel adenoviral 'gutless' vector (AGV) can enhance arteriogenesis in a rabbit hindlimb ischemia model. METHODS: Thirty-five male New Zealand white rabbits were randomized to the AGV-SPK group (n=13), AGV-null group (n=13), and control group (n=9). On day 10, after the induction of unilateral hindlimb ischemia, gene vectors or buffer were introduced and the effect examined on day 30, using calf blood pressure, quantitative angiographic analysis, and histology. RESULTS: Calf systolic blood pressure ratios of the ischemic limb to the normal limb on day 30 were 0.77+/-0.13 in control groups, including the AGV-null group, and 0.91+/-0.14 in the AGV-SPK group (P<0.05). Angiographic vessel counts were significantly increased (8.0+/-2.1 at baseline and 11.8+/-3.2 on day 30, P<0.001) in the AGV-SPK group. Histologic analysis showed that microscopic total vessel counts on day 30 were 3.5+/-1.8/field in the control and AGV-null group and 5.4+/-1.0/field in the AGV-SPK group. Arterioles (AGV-SPK; 3.0+/-0.8 versus control and AGV-null; 2.1+/-1.1, P<0.05) were significantly increased in the AGV-SPK group. CONCLUSIONS: This study shows that SPK promotes arteriogenesis, as evidenced by the maximal improvement in the blood pressure restoration and collateral vessel counts. SPK may be an important angiogenic target to improve perfusion in ischemic tissues. 相似文献
102.
103.
Deprivation of dietary nucleotides decreases protein synthesis in the liver and small intestine in rats 总被引:1,自引:0,他引:1
AT Lopez-Navarro MA Ortega J Peragon JD Bueno A Gil A Sanchez-Pozo 《Gastroenterology》1996,110(6):1760-1769
BACKGROUND & AIMS: Dietary nucleotides are reported to influence the growth and functioning of the liver and small intestine. The aim of this study was to examine the mechanism by which nucleotides exert their effects in these tissues by assessing protein synthesis activity and related parameters in the presence or absence of dietary nucleotides. METHODS: Rats were fed a purified diet with or without nucleotides for 10 days. Fractional protein synthesis rate, RNA and DNA concentrations, polysome size distribution, and number of ribosomes were assessed. RESULTS: Fractional protein synthesis rates of the liver and small intestine were lower in the nucleotide-deprived group than in the control group. In the liver, RNA concentration was also lower in the nucleotide-deprived group, but values in the small intestine were similar in the two groups. In the liver, deprivation of nucleotides resulted in a reduction in the number of ribosomes and in polysome breakdown. Protein and DNA concentrations did not vary in the liver; however, the concentration of DNA was lower in the small intestine of the nucleotide-deprived group than in the control group. CONCLUSIONS: Dietary nucleotides can modulate protein synthesis in the liver and small intestine as a result of tissue-specific nucleic acid changes. (Gastroenterology 1996 Jun;110(6):1760-9) 相似文献
104.
105.
106.
The formation of Ca++-dependent complexes of platelet membrane glycoproteins IIb and IIIa in solution as determined by crossed immunoelectrophoresis 总被引:29,自引:0,他引:29
Triton X-100 soluble proteins from 125I-labeled human platelets were studied by crossed immunoelectrophoresis employing a multispecific rabbit antibody raised against whole normal platelets. Emphasis was placed upon an analysis of immunoprecipitates containing 125I-labeled major membrane glycoproteins, and in particular, a prominent immunoprecipitate containing a glycoprotein antigen (s) previously designated as protein 16. SDS-polyacrylamide gel electrophoresis of protein 16 precipitated by a monospecific alloantibody. IgG L . . . , confirmed the presence of both glycoproteins IIb and IIIa. 125I-IgG L . . . , at concentration below that capable of precipitating protein 16 by itself, bound specifically to the precipitate containing protein 16 produced by the multispecific rabbit antibody. No other precipitates formed by the rabbit antibody contained either glycoprotein IIb or IIIa. When platelet proteins, incubated with optimum concentrations of ethylenediamine tetraacetic acid (EDTA) or ethyleneglycol bis (B- aminoethylether) NN1-tetraacetic acid (EGTA), were electrophoresed against the rabbit antibody, previously unobserved immunoprecipitates that contained either free glycoprotein IIb or free glycoprotein IIIa were detected. Upon readdition of excess Ca++, but not Mg++, to the same protein samples, a single immunoprecipitate containing both glycoproteins was once again observed. It is thus demonstrated that glycoproteins IIb and IIIa can form Ca++-dependent complexes (protein 16) in Triton X-100 extracts of normal platelets. The potential significance of the reversible association of these glycoproteins to normal platelet function is discussed. 相似文献
107.
SW Park TN Kim JH Yoon TH Kim JM Chung UB Jeon W Lee 《International urology and nephrology》2012,44(5):1397-1402
Objectives
To establish the undisputed the value of washout rate for adrenal adenoma using delayed enhanced CT, we evaluated diagnostic performance of cut-off value and delayed time of washout rate by final pathologic diagnosis in a multicenter study.Methods
We reviewed the pathologic and clinical records of 244 patients underwent adrenalectomies at 5 university hospitals between 2005 and 2009. We calculated the mean Housfield units (HU) of adrenal lesion at non-enhancing CT, and early and delayed enhanced CT using the region of interest. We used ROC curves to determine the specificity and sensitivity of non-enhanced CT scans and the washout rate according to the various cut-off for adrenal adenomas.Results
We divided the patients into adrenal adenoma group (n?=?138) and non-adrenal adenoma group (n?=?106) based on final pathologic report. Using the unenhanced images with a threshold of 10 HU, the sensitivity was 45.7?%, and the specificity was 97.1?%. Using the 15-min-washout rate with a threshold of 55?%, the sensitivity was 93.9?%, and the specificity was 95.8?%.Conclusions
Regardless of various CT machines and protocols, a washout rate of 15-min-delayed CT was most useful in the diagnosis of adrenal adenomas due to the early inflow and outflow of contrast media in the tissues of adrenal adenomas. 相似文献108.
M. Elisabeth Del Giudice Sheila-Mae Young Emily T. Vella Marla Ash Praveen Bansal Andrew Robinson Roland Skrastins Yee Ung Robert Zeldin Cheryl Levitt 《Canadian family physician Médecin de famille canadien》2014,60(8):711-716
Objective
The aim of this guideline is to assist FPs and other primary care providers with recognizing features that should raise their suspicions about the presence of lung cancer in their patients.Composition of the committee
Committee members were selected from among the regional primary care leads from the Cancer Care Ontario Provincial Primary Care and Cancer Network and from among the members of the Cancer Care Ontario Lung Cancer Disease Site Group.Methods
This guideline was developed through systematic review of the evidence base, synthesis of the evidence, and formal external review involving Canadian stakeholders to validate the relevance of recommendations.Report
Evidence-based guidelines were developed to improve the management of patients presenting with clinical features of lung cancer within the Canadian context.Conclusion
Earlier identification and referral of patients with lung cancer might ultimately help improve lung cancer morbidity and mortality. These guidelines might also be of value for informing the development of lung cancer diagnostic programs and for helping policy makers to ensure appropriate resources are in place.Lung cancer is the most common cause of cancer death in Canada.1 Lung cancers are frequently diagnosed at a late stage, and the prognosis is very poor.1 The chance of surviving lung cancer in Canada is low, with a 5-year survival rate of 13% for men and 19% for women.1 Delays in the diagnosis of lung cancer are well documented.2–11 This might in part be owing to patients and clinicians attributing the often common, atypical, or nonspecific symptoms of lung cancer to other, benign diseases.In order to provide guidance for the introduction of lung cancer diagnostic assessment programs (DAPs) in Ontario, the Cancer Care Ontario (CCO) Provincial Primary Care and Cancer Network initiated a collaboration in October 2009 with CCO’s Program in Evidence-based Care (PEBC) to form the Lung Cancer Referral Working Group. The working group was tasked with providing recommendations that would help FPs and other primary care providers recognize and initiate the management of undiagnosed patients presenting with signs or symptoms of lung cancer. The following questions were evaluated in completing this overall objective.- What main known risk factors are predictive of lung cancer?
- What signs, symptoms, and other clinical features are predictive of lung cancer?
- What is the diagnostic accuracy of investigations for lung cancer?
- Which patient and provider factors are associated with delayed referral?
- Does a delay in the time to consultation affect patient outcomes?
109.
Anna Wickbom Magnus Lindqvist Johan Bohr Kjell-Arne Ung Jan Bergman Sune Eriksson 《Scandinavian journal of gastroenterology》2013,48(6):726-729
In general, the colonic mucosa is macroscopically normal in collagenous colitis, although minor, non-specific abnormalities may be found. Significant endoscopic abnormalities, “mucosal tears” representing longitudinal mucosal lacerations, have been reported in a few patients with collagenous colitis. We report the cases of three women with collagenous colitis and mucosal tears detected at the index colonoscopy in order to illustrate the endoscopic characteristics and review the literature. Including the present cases, a total of 12 patients with mucosal tears and collagenous colitis have been reported. In 10 patients, the mucosal lacerations involved the ascending or the transverse colon. Three of the 12 patients had a colonic perforation immediately after the colonoscopy. The colonoscopist should be aware that the risk of perforation is likely to be increased when mucosal tears are present. 相似文献
110.
Fumiko Yano Taku Saito Naoshi Ogata Toshiko Yamazawa Masamitsu Iino Ung‐il Chung Hiroshi Kawaguchi 《Arthritis \u0026amp; Rheumatology》2013,65(2):429-435