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41.
Brijesh Takkar Vinod Kumar Renu Agrawal Raghav Ravani Shorya Azad 《Saudi Journal of Ophthalmology》2015,29(4):315-316
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
42.
Synthesis and Evaluation of New 4‐Chloro‐2‐(3‐chloro‐4‐fluorophenyl)‐5‐(aliphatic/cyclic saturated amino)pyridazin‐3(2H)‐one Derivatives as Anticancer,Antiangiogenic, and Antioxidant Agents 下载免费PDF全文
43.
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
44.
Ghayoumi A Raxwal V Cho S Myers J Chun S Froelicher VF 《Journal of cardiopulmonary rehabilitation》2002,22(6):399-407
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
45.
Edênia C. Menezes Relish Shah Lindsay Laughlin K. Yaragudri Vinod John F. Smiley Catarina Cunha Andrea Balla Henry Sershen Francisco X. Castellanos Andr Corvelo Ctia M. Teixeira 《The Journal of neuroscience》2021,41(12):2723
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
46.
Rakesh M. Suri Brian C. Gulack J. Matthew Brennan Vinod H. Thourani Dadi Dai Alan Zajarias Kevin L. Greason Christina M. Vassileva Verghese Mathew Vuyisile T. Nkomo Michael J. Mack Charanjit S. Rihal Lars G. Svensson Rick A. Nishimura Patrick T. O’Gara David R. Holmes Jr. 《The Annals of thoracic surgery》2015,100(6):2136-2146
47.
Background:
Partial tears of the anterior cruciate ligament (ACL) are common and usually present with symptomatic instability. The remnant fibers are usually removed and a traditional ACL reconstruction is done. But with increased understanding of ACL double bundle anatomy, the remnant tissue preservation along with a single bundle augmentation of the torn bundle is also suggested. The purpose of this study was to evaluate the results of selective anatomic augmentation of symptomatic partial ACL tears. Our hypothesis is that this selective augmentation of partial ACL tears could restore knee stability and function.Materials and Methods:
Consecutive cases of 314 ACL reconstructions, 40 patients had intact ACL fibers in the location corresponding to the anteromedial (AM) or posterolateral (PL) bundle and were diagnosed as partial ACL tears perioperatively. All patients underwent selective augmentation of the torn bundle, while keeping the remaining fibers intact using autogenous hamstring graft. A total of 38 patients (28 males, 10 females) were available with a minimum of 3 years followup. 26 cases had AM bundle tears and 12 cases had PL bundle tears respectively. Patients were assessed with International Knee Documentation Committee (IKDC) 2000 Knee Evaluation Form, Lysholm score; instrumented knee testing was performed with the arthrometer (KT 2000). Statistical analysis was performed to compare the preoperative and postoperative objective evaluation.Results:
At 3 years followup, 31.6% patients were graded A, 65.8% were graded B and 2.6% was graded C at IKDC objective evaluation. Manual laxity tests, Lysholm''s score, mean side to side instrumental laxity and Tegner activity score improved significantly. 76% patients returned to preinjury level of sports activity after augmentation.Conclusion:
The results of anatomic single bundle augmentation in partial ACL tears are encouraging with excellent improvement in functional scores, side to side laxity and return to sports activity. 相似文献48.
Pullarkat VA Bueso-Ramos C Lai R Kroft S Wilson CS Pullarkat ST Bu X Thein M Lee M Brynes RK 《American journal of hematology》2003,73(1):12-17
The majority of patients with systemic mastocytosis with associated clonal, hematological non-mast cell lineage disease (SM-AHNMD) have a myeloid stem cell malignancy including myelodysplastic syndromes (MDS), myelodysplastic/myeloproliferative disorders, acute myeloid leukemia (AML), or chronic myeloproliferative disease. The clinicopathologic features of SM-AHNMD have not been fully characterized. We describe seven cases of this entity: 3 with MDS, 3 with AML, and 1 with chronic myelomonocytic leukemia. In the majority of cases, SM was diagnosed concurrently with the myeloid malignancy and aberrant mast cell morphology was observed. The commonly described c-kit enzymatic site mutation Asp816Val was detected only in 2 cases, while 3 patients carried the Asp816His mutation. Among the 3 cases with AML, 2 patients carried the translocation t(8;21). On the basis of our results and other reported cases, there appears to be a specific association between SM and AML with t(8;21). Concurrent occurrence of SM may define a subset of patients with de novo AML and other myeloid malignancies who have an adverse prognosis. As clinically effective tyrosine kinase inhibitors that inhibit enzymatic-type c-kit mutations are being developed, detection of mast cell proliferation associated with myeloid malignancy may have important therapeutic implications. 相似文献
49.
Hemendra Kumar Agrawal Balvinder Singh Mohit Garg Vipin Khatkar Sumit Batr Vinod Kumar Sharma 《中华创伤杂志(英文版)》2015,18(3):170-174
Upper limb length discrepancy is a rare occurrence. Humerus shortening may need specialized treatment
to restore the functional and cosmetic status of upper limb. We report a case of humerus lengthening of 9 cm with a monorail external fixator and the result was observed during a 2-year follow-up. Humerus lengthening needs specialized focus as it is not only a cosmetic issue but also a functional demand. The monorail unilateral fixator is more functional and cosmetically acceptable, and thus becomes an effective treatment option. 相似文献
50.
Joshi V Sharma RC Singhi M Singh H Sharma K Sharma Y Adha S 《Journal of vector borne diseases》2005,42(1):25-29
BACKGROUND & OBJECTIVES: Malaria is the major health problem in western Rajasthan yet its vector fauna and transmission dynamics thereof is not understood properly. The present investigations report complete profile of qualitative and quantitative aspects of anopheline species occurring in different settings of desert ecosystem. METHODS: Area with irrigation through canal for more than 20 years (setting I), area with irrigation through canal for 10 years (setting II) and area without any irrigation (setting III) have been selected for studies. Species identification and their densities (per man hour) was made as per standard methods. RESULTS: In village of setting I, during rainy season, An. subpictus and An. stephensi were present while during winter season four species--An. subpictus, An. stephensi, An. culicifacies and An. annularis were collected. In all the villages of setting I, II and III no Anopheles mosquito was observed during summer season. In the villages of desert region without any irrigation facilities through any canal, the anopheline species were present only during rainy season. INTERPRETATION & CONCLUSION: An. stephensi is the major malaria vector of desert irrespective of whether the area is canal irrigated or not. During summer season absence of vector species in all the villages require further studies on micro-ecology of the species under desert conditions. 相似文献