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141.
Ines Valenta MD Alessandra Quercioli MD Gabriella Vincenti MD René Nkoulou MD Stephan Dewarrat MSc Olivier Rager MD Habib Zaidi PhD Yann Seimbille PhD Francois Mach MD Osman Ratib MD Thomas H. Schindler MD PhD 《Journal of nuclear cardiology》2010,17(6):1023-1033
Background
The aim of this study was to determine whether epicardial structural disease may affect the manifestation of a longitudinal decrease in myocardial blood flow (MBF) or MBF difference during hyperemia in cardiovascular risk individuals, and its dependency on the flow increase.Methods and Results
In 54 cardiovascular risk individuals (at risk) and in 26 healthy controls, MBF was measured with 13N-ammonia and PET/CT in mL/g/min at rest and during dipyridamole stimulation. Computed tomography coronary angiography (CTA) was performed using a 64-slice CT of a PET/CT system. Absolute MBFs during dipyridamole stimulation were mildly lower in the mid-distal than in the mid-LV myocardium in controls (2.20 ± .51 vs 2.29 ± .51, P < .0001), while it was more pronounced in at risk with normal and abnormal CTA (1.56 ± .42 vs 1.91 ± .46 and 1.18 ± .34 vs 1.51 ± .40 mL/g/min, respectively, P < .0001), resulting in a longitudinal MBF difference that was highest in at risk with normal CTA, intermediate in at risk abnormal CTA, and lowest in controls (.35 ± .16 and .22 ± .09 vs .09 ± .04 mL/g/min, respectively, P < .0001). On multivariate analysis, log-CCS and mid-LV hyperemic MBF increase, indicative of microvascular function, were independent predictors of the observed longitudinal MBF difference (P ≤ .004 by ANOVA).Conclusions
Epicardial structural disease and microvascular function are important determinants of an abnormal longitudinal MBF difference as determined with PET/CT. 相似文献142.
143.
Muhammad Khisroon Ajmal Khan Muhammad Imran Farrah Zaidi Ahmadullah Syeda Hira Fatima 《Archives of environmental & occupational health》2018,73(2):115-120
Different kinds of harmful raw materials are used in brick kilns for baking bricks, thus exerting negative effects on the health of brick kiln workers and nearby residents. The comet assay technique monitors DNA damage in lymphocytes of brick kiln workers. Blood samples were collected from 150 participants to conduct comet assay. The results indicated a highly significant increase (p < .0001) in DNA damage in brick kiln workers (171.9 ± 62.1) as compared with the control group (101.9 ± 48.3). Duration of occupational exposure had positive correlation (r = .823, p < .05) with DNA damage. Age and tobacco use had significant effects on total comet score (TCS) of exposed group as compared to control group (p < .05). In summary, these findings indicate greater genotoxicity in brick kiln workers. 相似文献
144.
M A Ghatei H K Datta M Zaidi D Bretherton-Watt S J Wimalawansa I MacIntyre S R Bloom 《The Journal of endocrinology》1990,124(2):R9-11
Amylin-amide has been implicated in the pathogenesis of type II diabetes due to its proposed inhibitory effect on insulin release from beta cells of the pancreatic islets, and on glucose uptake by the skeletal muscle. In experiments with rats and rabbits we failed to demonstrate these anti-insulin actions of amylin and amylin-amide. A single bolus dose of the two peptides (500 pmol) administered i.v. failed to suppress plasma insulin levels or to elevate blood glucose levels. The continuous infusion of amylin-amide into rabbits also failed to suppress the release of insulin in response to hyperglycaemia produced by an i.v. bolus injection of glucose. These in vivo observations imply that the amylin peptides may not have a primary physiological role in carbohydrate metabolism, but in view of our previous findings, we speculate that the peptide has a more prominent role in calcium homeostasis. 相似文献
145.
C J Murray D E Bell E DeJonghe S Zaidi C Michaud 《The Journal of tropical medicine and hygiene》1990,93(4):229-255
The Commission on Health Research for Development is an independent, international commission composed of 12 leaders from the fields of health research, social science research and development policy. Chaired by John Evans, the other Commissioners are Gelia Castillo, vice-chair, F. H. Abed, Sune Bergstrom, Doris Calloway, Esmat Ezzat, Demissie Habte, Walter Kamba, Adetokumbo Lucas, Adolfo Martinez-Palomo, Saburo Okita and V. Ramalingaswami. The Commission began its work in November 1987, charged with analysing the strengths, weaknesses and gaps in current research on health problems of developing countries, and making proposals and promoting action for improvement. The Commission is sponsored by a variety of foundations, bilateral donor agencies, and international organizations. The Commission's report was published in the spring of 1990. As part of the work of the Commission Secretariat, we have undertaken a study of financial resources devoted to research on the health problems of developing countries. The study which began in May 1988 has three objectives: (i) To describe the current pattern of funding for research on the health problems of developing countries. (ii) To provide a baseline against which future trends and/or new programmes can be measured. (iii) To explore the possibility of an ongoing information system on research on health problems of developing countries. 相似文献
146.
Nalbuphine (0.3 mgkg−1 ) and buprenorphine (2.5 μgkg−1 ) were compared as part of a total intravenous anaesthesia regimen using a propofol infusion in 60 patients undergoing laparoscopic cholecystectomy in a randomised double-blind study. Changes in haemodynamic variables greater than 20% from the baseline were noted. No difference was observed in blood pressure but the heart rate was significantly lower in the buprenorphine group. Intra-operative bradycardia (heart rate < 60 beatmin−1 ) occurred more often in the buprenorphine group. Recovery was fast and comparable with both drugs and no patient reported awareness. Quality of analgesia was similar in both groups. Both drugs provide suitable analgesic supplementation to total intravenous anaesthesia. 相似文献
147.
Lisa Y. Zaidi 《Journal of traumatic stress》1994,7(4):719-727
Recent research indicates that childhood abuse experiences characterize a large subset of psychiatric inpatients. This paper presents a time-limited pilot group developed for adult male abuse survivors in an inpatient setting using: (1) techniques adapted from the existing literature on treatment of abuse survivors; and (2) approaches deriving from the interface of theory and current manifestations of distress. The eclectic therapeutic approach incorporated psychoeducational, cognitive, behavioral, and art therapy techniques presented below in a session-by-session format.A version of this paper was presented at the Eighth Annual Meeting of the International Society for Traumatic Stress Studies, Los Angeles, CA, October 22, 1991. 相似文献
148.
Mone Zaidi Harry C Blair Baltit S Moonga Etsuko Abe Christopher L H Huang 《Journal of bone and mineral research》2003,18(4):599-609
Over the past decade, advances in molecular tools, stem cell differentiation, osteoclast and osteoblast signaling mechanisms, and genetically manipulated mice models have resulted in major breakthroughs in understanding osteoclast biology. This review focuses on key advances in our understanding of molecular mechanisms underlying the formation, function, and survival of osteoclasts. These include key signals mediating osteoclast differentiation, including PU.1, RANK, CSF-1/c-fms, and src, and key specializations of the osteoclast including HCl secretion driven by H+-ATPase and the secretion of collagenolytic enzymes including cathepsin K and matrix metalloproteinases (MMPs). These pathways and highly expressed proteins provide targets for specific therapies to modify bone degradation. The main outstanding issues, basic and translational, will be considered in relation to the osteoclast as a target for antiresorptive therapies. 相似文献
149.
Green tea, next to water, is the most popular and commonly consumed beverage in the world, especially in eastern countries. In prior studies we have shown that the polyphenolic fraction isolated from green tea (GTP) exerts antigenotoxic effects in various mutagenicity test systems (Mutat. Res., 223: 273-285, 1989) and that its topical application or oral feeding in drinking water protects against polycyclic aromatic hydrocarbon-induced skin tumor initiation and complete carcinogenesis in SENCAR and BALB/c mice [Cancer Lett., 42: 7-12, 1988; Carcinogenesis (Lond.), 10: 411-415, 1989] and UV B radiation-induced photocarcinogenesis in SKH-1 hairless mice [Carcinogenesis (Lond.), 12: 1527-1530, 1991]. In the present study we assessed the effect of skin application of GTP to SENCAR mice on 12-O-tetradecanoylphorbol-13-acetate (TPA) and other skin tumor promoter-caused induction of epidermal ornithine decarboxylase (ODC) activity. Topical application of GTP to mouse skin inhibited TPA-induced epidermal ODC activity in a dose-dependent manner. The inhibitory effect of GTP was also dependent on the time of its application relative to TPA treatment. Maximum inhibitory effect was observed when GTP was applied 30 min prior to topical application of TPA. GTP application to animals also inhibited the induction of epidermal ODC activity caused by several structurally different mouse skin tumor promoters. In order to identify which of the specific epicatechin derivatives present in GTP is responsible for these inhibitory effects, they were isolated from GTP and evaluated for their inhibitory effects against TPA-caused induction of epidermal ODC activity. Among these, (-)epigallocatechin-3-gallate (EGCG), which was the major constituent present in GTP by weight, exerted the maximum inhibition. EGCG also showed greater inhibitory effects against TPA-caused induction of epidermal ODC activity when compared with several other naturally occurring polyphenols. The results of this study suggest that GTP, specifically its epicatechin derivative EGCG, could provide anti-tumor-promoting effects against a wide spectrum of skin tumor promoters. 相似文献
150.