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The study objectives were to characterize the morphology of the parasitic forms and describe the prevalence and intensity of Haemogregarina spp. in a population of the turtle Podocnemis unifilis as well as to examine the relationships between parasitism and turtle variables such as gender, size, and weight. Samples were taken in the Tapajós and Jamanxim rivers, Itaituba, Pará state, Brazil. Blood was collected from the tail vein of 72 P. unifilis specimens, including 35 males, 36 females, and one unsexed juvenile. The prevalence of Haemogregarina spp. was 98 % (n?=?71). The mean parasite intensity of Haemogregarina spp. was 118 (1–582) parasites/2000 blood cells (6 %). There was no significant difference in the mean parasite intensity between male (137.68?±?121.8, n?=?35) and female turtles (101.42?±?123.59, n?=?35). There was no relationship between parasite intensity and carapace length. Although the relationship between parasite intensity and host body weight was significant, the relationship was weak. This is the first study on Haemogregarina parasitism with a relatively high number of turtles in Brazil.  相似文献   
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INTRODUCTION: Long-term exposure to antidepressants is required to prevent relapses and recurrences in patients with recurrent major depression. Furthermore, a good pharmacological compliance is the key to successful long-term treatment. Since the early phases of a treatment influence long-term compliance and compliance is adversely affected by poorly tolerated treatments, efficacy and tolerability of paroxetine and amitryptiline over 12 weeks were compared as an introduction to the issue of long-term compliance to these two agents. METHOD: A 12-week, randomized, double-blind, doubledummy, parallel-group trial which involved 129 patients with recurrent major depression. RESULTS: Both paroxetine and amitriptyline were effective in controlling the symptoms of depression, as shown by the reduction in HAMD total score and CGI severity-of-illness score at endpoint compared to baseline. There was no statistically or clinically significant difference between the two treatments in terms of efficacy. However, marked numerical differences were noted in tolerability: the percentage of patients who reported treatment-emergent adverse experiences was greater in the amitriptyline group (40.0% vs 28.1%). This difference was mainly due to anticholinergic adverse events, which were six times more frequent with amitriptyline than with paroxetine. CONCLUSION: When compared with amitriptyline, paroxetine should allow patients with recurrent major depression to receive an equally effective treatment with a relatively lower incidence of adverse experiences.  相似文献   
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Background: Simvastatin (SMV) is a specific competitive inhibitor of 3‐hydroxy‐2‐methyl‐glutaryl coenzyme A reductase. Recently, it has been reported that statins promote bone formation. The present study is designed to investigate the effectiveness of 1.2% SMV in an indigenously prepared, biodegradable, controlled‐release gel as an adjunct to scaling and root planing (SRP) in the treatment of patients with type 2 diabetes and chronic periodontitis (CP). Methods: Thirty‐eight patients were categorized into two treatment groups: SRP plus 1.2% SMV and SRP plus placebo. Clinical parameters were recorded at baseline before SRP and at 3, 6, and 9 months; they included modified sulcus bleeding index (mSBI), probing depth (PD), and clinical attachment level (CAL). At baseline and after 6 and 9 months, radiologic assessment of intrabony defect (IBD) fill was done using computer‐aided software. Results: Mean PD reduction and mean CAL gain were found to be greater in the SMV group than the placebo group at 3, 6, and 9 months. Furthermore, significantly greater mean percentage of bone fill was found in the SMV group (32.64% ± 12.90%) compared to the placebo group (4.22% ± 9.75%) after 9 months. Conclusion: There was a greater decrease in mSBI and PD and more CAL gain with significant IBD fill at sites treated with SRP plus locally delivered SMV in patients with type 2 diabetes and CP.  相似文献   
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Purpose:The optometry profession has experienced massive changes amid lockdown in COVID 19 pandemic. This study gauges the impact of COVID-19 on optometry education and practices in India.Methods:The impact of COVID-19 among key stakeholders of Indian optometry that included educators, students, and practitioners was surveyed. The content validity of the survey tool was achieved through a focused group discussion with experts.Results:Of the 1408 responses, 118 were educators, 845 were students and 445 were practitioners. Post COVID-19 lock-down, a high percentage of students (96%) and educators (94%) were now using online mode of education to learn and teach. The blended learning methods were reported to be used by 81% of educators. Practical skills were the most difficult to teach by educators and to learn by students. Almost a third of the students were concerned about their internships and job opportunities amid the pandemic. Practitioners felt confident in performing routine eye examinations with personal protective equipment (PPE). Telemedicine was found to be adopted by 55% of the private practitioners and 49% of the eye hospitals.Conclusion:The COVID-19 pandemic has provided an opportunity to reform Indian optometry education through blended learning methods. Optometry practices changed and adapted instantly to the new hygiene norms that have raised the standard of care provided to patients. Telemedicine emerged as a mode of providing care by optometrists. Overall, all key stakeholders of optometry in India were found to have adapted well to the sudden changes due to COVID 19 pandemic.  相似文献   
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The nervous tissue of many vertebrates, including humans, can synthesize beta-alanyl-L-histidine (carnosine). The biological functions of carnosine are still open to question, although several theories supported by strong experimental data have been proposed. The objective of this study was to examine the effects of carnosine on neurotoxicity in differentiated rat pheochromocytoma (PC12) cells. Neurotoxicity was induced by N-methyl-D-aspartate (NMDA), which caused time- and concentration-dependent cell death as measured by MTT and LDH assays. Pretreatment with carnosine significantly prevented the neurotoxicity in a concentration-dependent manner. The protective effect of carnosine was antagonized by the H1 receptor antagonist pyrilamine, but not by the H2 receptor antagonist cimetidine. In addition, alpha-fluoromethylhistidine, a histidine decarboxylase inhibitor, slightly reversed the protective action of carnosine. These results indicate that carnosine can effectively protect against NMDA-induced necrosis in PC12 cells, and its protection may in part be due to the activation of the postsynaptic histamine H1 receptor. The study suggests that carnosine may be an endogenous protective factor and calls for its further study as a new anti-excitotoxic agent.  相似文献   
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