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61.
Non-invasive imaging plays a growing role in the diagnosis and management of ischemic heart disease from its earliest manifestations of endothelial dysfunction to myocardial infarction along the myocardial ischemic cascade. Experts representing the North American Society for Cardiovascular Imaging and the European Society of Cardiac Radiology have worked together to organize the role of non-invasive imaging along the framework of the ischemic cascade. The current status of non-invasive imaging for ischemic heart disease is reviewed along with the role of imaging for guiding surgical planning. The issue of cost effectiveness is also considered. Preclinical disease is primarily assessed through the coronary artery calcium score and used for risk assessment. Once the patient becomes symptomatic, other imaging tests including echocardiography, CCTA, SPECT, PET and CMR may be useful. CCTA appears to be a cost-effective gatekeeper. Post infarction CMR and PET are the preferred modalities. Imaging is increasingly used for surgical planning of patients who may require coronary artery bypass.  相似文献   
62.
The present study reports the quantification of changes in the contents of plant pigments and ascorbic acid as influenced by the planting time and fruit picking stages in sweet pepper. The crop was planted on five different dates at 10 days interval in randomized block design under open field conditions in temperate area to quantify the changes which took place in the contents of plant pigments and ascorbic acid in green and red fruits. The results showed that the planting time and fruit picking stage had significant (p ≤ 0.05) influence on plant pigments and ascorbic acid contents in sweet pepper. The last week of May was observed as the optimal planting time when fruits exhibited higher contents of lycopene, β-carotene and ascorbic acid. The red fruit picking stage had significantly higher concentration of these phytonutrients than the green picking stage. In order to pick-up fruits at right stage and time with high plant pigments and ascorbic acid contents, these results would help meet out the increasing demand of sweet pepper quality fruits.  相似文献   
63.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The study was conducted to identify the antiproliferative property and the mode of action of...  相似文献   
64.
Surgical emphysema is defined as gas or air trapped in the subcutaneous tissue plane. Here, we report a rare case of bilateral periorbital and cervicofacial subcutaneous emphysema following a vitreoretinal surgery for inadvertent globe perforation during the administration of peribulbar anesthesia. This condition, although self-resolving when restricted to the subcutaneous plane has the potential to spread into deeper tissue planes such as the retropharyngeal space. The presence of crepitus helps to distinguish it from angioneurotic edema. Ophthalmologists must be sensitive to the fact that surgical emphysema can be a very rare, but possible complication of an intraocular surgery following globe perforation.  相似文献   
65.
Small intraocular foreign body in the outer coats of the eye may be wrongly interpreted as optic nerve head on ultrasound imaging. Such errors can be avoided by performing multiple sonography scans in different axes.  相似文献   
66.
67.
Normal cells in culture are used to investigate the underlying mechanisms of DNA synthesis because they retain regulatory characteristics of the in vivo replication machinery. During the last few years new studies have identified a number of genetic changes that occur during in vitro ageing, providing insight into the progressive decline in biological function that occurs during ageing. Maintaining genomic integrity in eukaryotic organisms requires precisely coordinated replication of the genome during mitosis, which is the most fundamental aspect of living cells. To achieve this coordinated replication, eukaryotic cells employ an ordered series of steps to form several key protein assemblies at origins of replication. Major progress has recently been made in identifying the enzymes, and other proteins, of DNA replication that are recruited to origin sites and the order in which they are recruited during the process of replication. More than 20 proteins, including DNA polymerases, have been identified as essential components that must be preassembled at replication origins for the initiation of DNA synthesis. Of the polymerases, DNA polymerase alpha-primase (pol alpha) is of particular importance since its function is fundamental to understanding the initiation mechanism of eukaryotic DNA replication. DNA must be replicated with high fidelity to ensure the accurate transfer of genetic information to progeny cells, and decreases in DNA pol alpha activity and fidelity, which are coordinated with cell cycle progression, have been shown to be important facets of a probable intrinsic cause of genetic alterations during in vitro ageing. This has led to the proposal that pol alpha activity and function is one of the crucial determinants in ageing. In this review we summarize the current state of knowledge of DNA pol alpha function in the regulation of DNA replication and focus in particular on its interactive tasks with other proteins during in vitro ageing.  相似文献   
68.
Severe aplastic anemia is a well-recognized complication of ticlopidine therapy that carries a high mortality. Therapy with colony-stimulating factors or corticosteroids has been largely ineffective in this disorder. We report a case of ticlopidine-induced aplastic anemia that was successfully treated with cyclosporine and high-dose dexamethasone. The patient rapidly responded to immunosuppressive therapy and had a normal hemogram after cessation of immunosuppression. On long-term follow-up, the patient developed a progressive macrocytic anemia. Repeat bone marrow evaluation demonstrated myelodysplasia with erythroid hypoplasia. An associated chromosomal abnormality consisting of a t(3;16) (q21; p13.3) translocation was detected. This is the first report of a chromosomal abnormality associated with ticlopidine induced marrow aplastic anemia.  相似文献   
69.
PURPOSE: The authors evaluate the prognostic value of treadmill testing in a large consecutive series of patients with chronic coronary artery disease. Exercise testing is widely performed, but analyses of the prognostic value of test results have largely concentrated on patients referred for the diagnosis of coronary artery disease, patients after an acute coronary event or procedure, or patients with congestive heart failure. METHODS: All patients referred for evaluation at two university-affiliated Veterans Affairs Medical Centers who underwent exercise treadmill tests for clinical indications between 1987 and 2000 were determined to be dead or alive using the Social Security Death Index after a mean 5.8-year follow-up. Patients without established heart disease and those with congestive heart failure were excluded, leaving the target population of those with a history myocardial infarction or coronary intervention. Clinical and exercise test variables were collected prospectively according to standard definitions; testing and data management were performed in a standardized fashion using a computer-assisted protocol. All-cause mortality was used as the endpoint for follow-up. Standard survival analysis was performed including Kaplan Meier curves and the Cox Hazard Model. RESULTS: Of the 1,473 patients with coronary artery disease who had exercise testing, 273 (19%) patients had a revascularization procedure (Revascularization group); 813 (55%) had a history of myocardial infarction, diagnostic Q waves (MI group), or both; and 387 (26%) had a history of myocardial infarction or Q wave and revascularization (Combined group). Mean age of the patients was 61.8 +/- 9 years. A total of 401 deaths occurred during a mean follow-up of 5.8 years with an annual mortality rate of 4.5%. Only two variables, age and maximal exercise capacity, were independently and statistically associated with time to death in all three groups and were the strongest predictors of all cause mortality. CONCLUSION: A simple score based on METs, age, and history of myocardial infarction or diagnostic Q waves can stratify prognosis in patients with chronic coronary artery disease. The score enabled the identification of a group at low risk (32% of the cohort) with an annual mortality rate of 2%, a group at intermediate risk (42% of the cohort) with an annual mortality rate of about 4%, and a group at high risk (26% of the cohort) with an average annual mortality rate of approximately 7%.  相似文献   
70.
Early life is a sensitive period, in which enhanced neural plasticity allows the developing brain to adapt to its environment. This plasticity can also be a risk factor in which maladaptive development can lead to long-lasting behavioral deficits. Here, we test how early-life exposure to the selective-serotonin-reuptake-inhibitor (SSRI), fluoxetine, affects motivation, and dopaminergic signaling in adulthood. We show for the first time that mice exposed to fluoxetine in the early postnatal period exhibit a reduction in effort-related motivation. These mice also show blunted responses to amphetamine and reduced dopaminergic activation in a sucrose reward task. Interestingly, we find that the reduction in motivation can be rescued in the adult by administering bupropion, a dopamine-norepinephrine reuptake inhibitor used as an antidepressant and a smoke cessation aid but not by fluoxetine. Taken together, our studies highlight the effects of early postnatal exposure of fluoxetine on motivation and demonstrate the involvement of the dopaminergic system in this process.SIGNIFICANCE STATEMENT The developmental period is characterized by enhanced plasticity. During this period, environmental factors have the potential to lead to enduring behavioral changes. Here, we show that exposure to the SSRI fluoxetine during a restricted period in early life leads to a reduction in adult motivation. We further show that this reduction is associated with decreased dopaminergic responsivity. Finally, we show that motivational deficits induced by early-life fluoxetine exposure can be rescued by adult administration of bupropion but not by fluoxetine.  相似文献   
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