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81.
Amany H Ahmed KJ Shankar Hossein Eftekhari MS Munir Jillian Robertson Alan Brewer Igor V Stupin S Ward Casscells 《Experimental & Clinical Cardiology》2007,12(4):189-196
Silent myocardial ischemia (SMI) is increasingly being recognized as part of the spectrum of ischemic heart disease. The spectrum of SMI ranges from asymptomatic coronary artery disease to critical illness necessitating intensive care. Although many diagnostic tools have been used to identify low- and high-risk subgroups, their use is limited by modest sensitivities and specificities. The present review identifies current concepts in the management of SMI in various clinical settings, as well as emerging technologies that may simplify the diagnosis and treatment of this condition. 相似文献
82.
Michelle Goldsammler Sangita K. Jindal Amanda Kallen Natu Mmbaga Lubna Pal 《Journal of assisted reproduction and genetics》2015,32(4):551-555
Purpose
To determine if blood type in infertile women relates to the likelihood for live birth (LB) following IVF, and to the etiology for infertility.Methods
Retrospective study of patients undergoing IVF at two academic centers in the northeast US. Relationships between blood type (A, B, AB, O) and patient characteristics, IVF cycle parameters and LB were assessed utilizing multivariable logistic regression analyses.Results
In the studied population (n = 626), women with type O were significantly more likely to have baseline FSH > 10 IU/L after adjusting for age, BMI and race (OR 5.09, 95 % CI 1.4–18.7, p = 0.01). Conversely, women with blood type A were significantly more likely to have ovulatory infertility compared to those with blood type O after adjusting for age and BMI (OR 3.2, 95 % CI 1.7–6.2). Blood type B was associated with increased likelihood of live birth (OR 1.9, 95 % CI 1.10–3.41, p = 0.03) after adjusting for factors recognized to impact IVF outcome.Conclusion
Ovulatory infertility and baseline FSH > 10 IU/L were more prevalent in women with blood type A and O respectively. However, those of blood type B had significantly higher odds for LB compared to other blood types after adjusting for factors recognized to impact on IVF cycle outcome. While underlying mechanisms are unclear, for infertile women, patient’s blood type is seemingly relevant for IVF cycle outcome. 相似文献83.
Neutrophil elastase produces 52-kD and 30-kD glucocorticoid receptor fragments in the cytosol of human leukemia cells 总被引:1,自引:0,他引:1
Characterization of glucocorticoid receptors in leukemia cells is important to understand mechanisms of glucocorticoid resistance but has been impeded by receptor fragmentation in cytosol extracts. We recently found that formation of 52- and 30-kilodalton (kD) glucocorticoid receptor fragments in cytosol of leukemia cells is due to proteolysis and is blocked by diisopropylfluorophosphate (DFP). In the present study, we identify a 28-kD serine protease in cytosol of leukemia cells that binds [3H]DFP and correlates with the formation of 52- and 30-kD receptor fragments. This protease is immunoprecipitated by antiserum to neutrophil elastase. Limited digestion of [3H]dexamethasone-21-mesylate- labeled receptors by purified neutrophil elastase produces 52- and 30- kD receptor fragments. Receptor fragmentation in the cytosol of leukemia cells in inhibited by methoxysuccinyl-alanyl-alanyl-prolyl- valyl-chloromethylketone, a highly specific inhibitor of neutrophil elastase. The addition of as few as 5% neutrophils to a lymphoid cell suspension provides sufficient elastase to produce receptor fragmentation. Our findings indicate that neutrophil elastase is responsible for receptor fragmentation in the cytosol of leukemia cells. The neutrophil elastase may be endogenous to the leukemia cells or may come from neutrophils that contaminate leukemia cell suspensions. 相似文献
84.
Deficiency of intact thrombospondin and membrane glycoprotein Ia in platelets with defective collagen-induced aggregation and spontaneous loss of disorder 总被引:11,自引:7,他引:11
Kehrel B; Balleisen L; Kokott R; Mesters R; Stenzinger W; Clemetson KJ; van de Loo J 《Blood》1988,71(4):1074-1078
Platelets from a patient with a severe lifelong bleeding tendency, which later spontaneously disappeared, lacked intact thrombospondin and glycoprotein (GP) Ia. Before disappearance of the bleeding disorder, results of coagulation studies and platelet aggregation in response to adenosine diphosphate (ADP), arachidonic acid, thrombin, A23187, epinephrine, and ristocetin were normal. In contrast, aggregation only occurred in the presence of collagen or wheat germ agglutinin at unusually high doses of these agonists. The platelets adhered normally to purified bovine and human type I collagen, and they did not spread in the presence of methylated type I collagen. No collagen-induced clot retraction was observed. Two-dimensional gel electrophoretic analyses of platelet proteins and immunologic studies showed that intact thrombospondin and GP Ia were absent. Aggregation in response to collagen could be restored by adding thrombospondin. Disappearance of the bleeding tendency occurred at the onset of menopause; subsequent analyses revealed that thrombospondin and GP Ia were present in platelets and that collagen-induced platelet aggregation was normal. These results suggest that both thrombospondin and GP Ia are essential in collagen-induced platelet aggregation. The spontaneous disappearance of the bleeding tendency may have been related to hormonal influences. 相似文献
85.
Schmidt GM; Bross KJ; Blume KG; Enders N; Santos S; Novitski M; Chillar RK 《Blood》1980,55(2):299-303
An immunohistochemical procedure for the detection of immunoglobulin G adherent to platelets is described. The peroxidase anti-peroxidase method is used to detect antibody activity directed against platelets from normal donors in the sera from 305 individuals. These subjects were divided into three groups: group 1, patients referred for tissue typing; group 2, healthy normal females; group 3, healthy normal males. In group 1, 28% of the sera were found to be positive; in most of these a history of prior transfusions was obtained. In group 2, 7.4% were found to be positive, most having previous pregnancies. Only 1% were found to be positive in group 3, and no reason for presensitization was found. Results from the indirect immunofluorescence technique served as a control and as a means to compare the sensitivity. Under the conditions chosen, the peroxidase anti-peroxidase test was two to eight times more sensitive than the immunofluorescence technique. Specificity of the peroxidase anti-peroxidase technique was demonstrated using a monospecific anti-PLA1 antiserum. It is concluded that the peroxidase anti-peroxidase slide technique may be a useful tool in the study of platelet-related immunophenomena. 相似文献
86.
R Yamamoto C B Kallen G O Babalola H Rennert J T Billheimer J F Strauss rd 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(2):463-467
We report the cloning and expression of a cDNA encoding human sterol carrier protein 2 (SCP2). The 1.3-kilobase (kb) cDNA contains an open reading frame which encompasses a 143-amino acid sequence which is 89% identical to the rat SCP2 amino acid sequence. The deduced amino acid sequence of the polypeptide reveals a 20-residue amino-terminal leader sequence in front of the mature polypeptide, which contains a carboxyl-terminal tripeptide (Ala-Lys-Leu) related to the peroxisome targeting sequence. The expressed cDNA in COS-7 cells yields a 15.3-kDa polypeptide and increased amounts of a 13.2-kDa polypeptide, both reacting with a specific rabbit antiserum to rat liver SCP2. The cDNA insert hybridizes with 3.2- and 1.8-kb mRNA species in human liver poly(A)+ RNA. In human fibroblasts and placenta the 1.8-kb mRNA was most abundant. Southern blot analysis suggests either that there are multiple copies of the SCP2 gene in the human genome or that the SCP2 gene is very large. Coexpression of the SCP2 cDNA with expression vectors for cholesterol side-chain cleavage enzyme and adrenodoxin resulted in a 2.5-fold enhancement of progestin synthesis over that obtained with expression of the steroidogenic enzyme system alone. These findings are concordant with the notion that SCP2 plays a role in regulating steroidogenesis, among other possible functions. 相似文献
87.
GF Nash KJ Turner T Hickish J Smith M Chand BJ Moran 《Annals of the Royal College of Surgeons of England》2012,94(7):456-462
Adenocarcinoma of the prostate and rectum are common male pelvic cancers and may present synchronously or metachronously and, due to their anatomic proximity. The treatment of rectal or prostate cancer (in particular surgery and/or radiotherapy) may alter the presentation, incidence and management should a metachronous tumour develop. This review focuses on the interaction between prostatic and rectal cancer diagnosis and management. We have restricted the scope of this large topic to general considerations, management of rectal cancer after prostate cancer treatment and vice versa, management of synchronous disease and cancer follow-up issues. 相似文献
88.
Twenty patients, aged 4 months to 58 years, were evaluated for liver transplantation by duplex sonography, and 15 transplantations were completed; 42 postoperative examinations were performed. Sonographic findings were correlated with seven preoperative and five postoperative angiographic evaluations. Preoperative duplex US findings included tumors, portal vein occlusion, varices, biliary obstruction, and variant vascular anatomy. Postoperative findings included hepatic artery occlusion, portal vein occlusions (one with cavernous transformation), portal vein stenosis, biliary obstruction, intrahepatic and extrahepatic fluid collections, and air in the portal vein due to ischemic bowel. Use of angiography allowed confirmation of the vascular abnormalities and demonstrated evidence of rejection in patients with normal Doppler waveforms. Duplex sonography is a valuable portable technique for evaluating these patients and can be used in triage of patients requiring angiography. 相似文献
89.
90.
2-[对-(二甲氨基)苯乙烯]氯化甲基吡啶(DSPM-Cl),是由氯取代2-[对-(二甲氨基)苯乙烯]碘化甲基吡啶(DSPM)上的碘而得。本文应用心电图、机械收缩描记方法及细胞内标准微电极技术,研究DSPM-Cl对大鼠心电图(ECG)、豚鼠心房肌量效曲线及对豚鼠乳头肌快反应动作电位(AP)、高钾除极慢反应动作电位(SAP)的影响。结果显示,DSPM-Cl(2mg·kg-1)对大鼠有明显的负性频率、负性传导作用,分别使PP间期、PR间期延长达66.2%(P<0.01),17.0%(P<0.01),50μmol·L-1能明显抑制左心房收缩力,非竟争性拮抗Iso及CaCl2对豚鼠左心房的正性肌力作用,PD2'分别为4.6,4.34,100μmol·L-1DSPM-Cl延长动作电位时程APD90,有效不应期(ERP),降低高钾除极豚鼠乳头肌0期最大上升速率Vmax,其作用与Ver相似,提示DSPM-Cl可能为钙拮抗剂。 相似文献