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To understand antioxidant activity and the role played by melatonin, we have designed and tested several new compounds. We present the results in terms of structure-activity relationships, focusing on the lack of the methoxy group and the influence of the amide side chain. Antioxidant activity of melatonin and some new melatonin analogue indole derivatives were investigated, using lipid peroxidation and superoxide anion radical scavenger activity assays, in rat liver tissue homogenate. Most of the compounds were found to be very potent inhibitors of malondialdehyde (MDA) formation at 10−3M. Inhibition rates ranged from 75-44 %. However, no significant inhibitory effect was obtained on superoxide anion formation. Consequently, it can be concluded that these compounds exhibit important LP activity compared to melatonin.  相似文献   
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This cross-sectional study investigated the associations of psychosocial factors relevant to recovery from substance use disorders with monocyte activation and HIV persistence in a sample of 84 HIV-positive, methamphetamine-using sexual minority men with undetectable HIV viral load (<40 copies/mL). We examined if psychosocial factors were associated with decreased soluble CD14 (sCD14) and lower proviral HIV DNA. Multiple linear regression models adjusted for age, anti-retroviral therapy regimen, and CD4+ T-cell count. Time on ART was also included in models examining proviral HIV DNA. Greater self-efficacy for managing methamphetamine triggers and higher social support for abstinence were independently associated with lower sCD14. Greater social support for abstinence was also independently associated with lower proviral HIV DNA. Psychosocial factors relevant to recovery from substance use disorders are associated with lower monocyte activation and decreased proviral HIV DNA. Findings underscore the need for longitudinal research to identify plausible mechanisms linking psychosocial factors and substance use with biological processes relevant to HIV pathogenesis.

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BACKGROUND: Peutz-Jeghers Syndrome (PJS) is a rare autosomal dominant disorder characterized by gastrointestinal hamartomatous polyps and mucocutaneous pigmentation. Patients with PJS have increased risk for gastrointestinal, breast, and female genital tract cancers. CASE: Multiple genital tract cancers in a 34-year-old woman with PJS are described. The patient, who was admitted to our department with severe vaginal bleeding, was performed right salpingo-oophorectomy because of pure gonadoblastoma in 1996. In 2003, concomitant to cervical carcinoma, breast cancer was diagnosed. Patient underwent left modified radical mastectomy due to the invasive papillary carcinoma. The patient received six cycles combination chemotherapy and radiation therapy because of stage IIIB cervical cancer. CONCLUSION(S): This is the first case report presenting PJS associated with multiple genital tract tumors including ovarian gonadoblastoma in literature. The clinical significance of these tumors in PJS patients has been reviewed.  相似文献   
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Objective The aim of this study was to evaluate the changes in follicular development, serum hormonal levels, and endometrium in the pre-implantation period of rats by using recombinant FSH (rFSH) without human chorionic gonadotropin (hCG). Methods Thirty female rats were studied in six groups of five specimens. Two groups determined as controls (groups 1 and 2). Two groups received constant doses of rFSH (groups 3 and 4) and other two decreasing doses (groups 5 and 6). One of the paired groups was mated. Uterus, ovaries, and blood samples were taken from non-mated groups (groups 1, 3, and 5) at the proestrus period and from mated groups (groups 2, 4, and 6) in the pre-implantation period. Results In non-mated groups antral follicles and corpus luteum periodicum and in mated groups antral follicles, corpus luteum periodicum, and corpus luteum graviditatis were increased in rFSH groups, especially in decreasing dose groups. Estradiol (E2) levels were increased and progesterone (P)/E2 ratio was significantly decreased in decreasing dose groups. Endometrium surface epithelium was columnar, irregular, and folded in rFSH groups. Endometrium glandular epithelium was cuboidal in all groups. In decreasing dose groups endometrial stroma was smooth and fibroblastic. Mitotic indices of endometrium surface, glandular epithelium, and stroma were significantly decreased in rFSH groups. Primary follicles and P levels showed no change. Conclusion It seems likely that decreasing doses of rFSH might be used in order to improve follicular development, although it has negative effects with E2 on endometrium in the pre-implantation period of rats.  相似文献   
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In this study, we aimed to compare the effects of forced-air warming upper body blankets and forced-air warming underbody blankets on intraoperative hypothermia in patients who were planned to undergo open abdominal surgical operations in which extensive heat loss occurs. This prospective and randomized study included 92 patients who would undergo lower abdominal surgery under general anesthesia. Patients were randomized by closed envelope method and divided into two groups. Group I (n:46) included the patients who would receive warming with forced-air warming upper body blanket, and Group II (n:46) consisted of the patients who received warming with forced-air warming underbody blanket. Central body temperature was recorded by measuring with a temperature probe placed in distal esophagus. Demographic data, amount of fentanyl, crystalloid and blood products used, duration of operation, type of operation, hemodynamic parameters, shivering and thermal damage information were recorded. There was not any statistically significant difference among the patients in terms of demographic data, amount of fentanyl, crystalloid and blood products used, duration and type of operation and hemodynamic parameters. No difference was found between the groups in terms of body temperatures (Group I:36.1?°C, Group II:36.3?°C, respectively) (P?>?0.05). Forced air warming underbody blanket can be as effective as forced-air warming upper body blankets in preventing intraoperative hypothermia. They can be alternative in cases where use of forced-air warming upper body blankets is not feasible.  相似文献   
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Objectives

The present study aims to specify the role of l-carnitine in the pathogenesis of endometrial cancer by comparing the serum total l-carnitine levels of endometrial cancer patients with those of healthy women.

Methods

Serum total l-carnitine concentrations were measured in patients with endometrioid-type endometrial cancer (n = 20) and healthy controls (n = 20) who were matched with respect to age and body mass index (BMI).

Results

Stage I endometrial cancer was diagnosed in 12 women (60.0 %) whereas three women (15.0 %) had stage II disease, three women (15.0 %) had stage III disease and two women (10.0 %) had stage IV disease. The healthy controls and endometrial cancer patients were statistically similar in aspect of age, gravidity, parity, BMI, waist-to-thigh ratio, waist-to-hip ratio, menopause, complete blood count parameters, and serum biochemistry. Serum total l-carnitine levels of women with endometrial cancer were significantly lower than those of healthy women (respectively, 5,519.4 ± 2,712.5 vs 7,940.8 ± 3,566.6 ng/dl, p = 0.021). Moreover, serum total l-carnitine levels decreased significantly and progressively with advancing stage (stage I vs II vs III vs IV; 6,294.0 ± 2,885.1 vs 5,800.0 ± 441.2 vs 4,016.0 ± 2,833.3 vs 2,560.0 ± 67.9 ng/dl; p = 0.021).

Conclusions

This is the first study to hypothesize that l-carnitine deficiency participates in the pathogenesis of endometrial cancer by means of a mechanism which is unrelated with obesity and increased amount of fat in human body.
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BackgroundWorkplace burnout among healthcare professionals is a critical public health concern. Few studies have examined organizational and individual factors associated with burnout across healthcare professional groups.ObjectiveThe purpose of this study was to examine the association between practice adaptive reserve (PAR) and individual behavioural response to change and burnout among healthcare professionals in primary care.DesignThis cross-sectional study used survey data from 154 primary care practices participating in the EvidenceNOW Heart of Virginia Healthcare initiative.ParticipantsWe analysed data from 1279 healthcare professionals in Virginia. Our sample included physicians, advanced practice clinicians, clinical support staff and administrative staff.Main MeasuresWe used the PAR instrument to measure organizational capacity for change and the Change Diagnostic Index© (CDI) to measure individual behavioural response, which achieved a 76% response rate. Logistic regression analysis was used to estimate the effects of PAR and CDI on burnout.Key ResultsAs organizational capacity for change increased, burnout in healthcare professionals decreased by 51% (OR: 0.49; 95% CI, 0.33, 0.73). As healthcare professionals showed improved response toward change, burnout decreased by 84% (OR: 0.16; 95% CI, 0.11, 0.23). Analysis by healthcare professional type revealed a significant association between high organizational capacity for change, positive response to change and low burnout among administrative staff (OR: 2.92; 95% CI, 1.37, 6.24). Increased hours of work per week was associated with higher odds of burnout (OR: 1.07; 95% CI, 1.05, 1.10) across healthcare professional groups.ConclusionAs transformation efforts in primary care continue, it is critical to understand the influence of these initiatives on healthcare professionals’ well-being. Efforts to reduce burnout among healthcare professionals are needed at both a system and organizational level. Building organizational capacity for change, supporting providers and staff during major change and consideration of individual workload may reduce levels of burnout.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-020-06367-z.KEY WORDS: adaptive reserve, burnout, practice transformation, primary care, well-being  相似文献   
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