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51.
R G Wilcox 《BMJ (Clinical research ed.)》1978,1(6126):1513-1515
In 70 obese women no correlation was found between body weight and serum cholesterol or triglyceride concentrations, but there was a significant correlation between weight and blood pressure. Weight reduction by diet or jejunoileal shunt was not accompanied by any significant change in serum lipid concentrations other than the decrease in serum cholesterol expected after intestinal bypass. Twelve months after bypass surgery was carried out on 14 patients, however, both systolic and diastolic blood pressures were significantly reduced and at levels appropriate to the patients'' new weights. These results suggest that obesity in women cannot be taken to indicate the presence of hyperlipidaemia and that sustained weight loss may lower blood pressure. 相似文献
52.
Nitrosoguanidine induced mutants of Anabaena cylindrica have been obtained, which are altered in heterocyst spacing. In the wild type organism the pattern is composed of single intercalary heterocysts. The mutant patterns fall into several classes: those with only terminal heterocysts, with both terminal and intercalary heterocysts, with groups of heterocysts and those totally lacking heterocysts. The mutants are described in detail, and the various pattern modifications are interpreted in terms of a model we have proposed. 相似文献
53.
Laura Noël-Romas Michelle Perner Refilwe Molatlhegi Christina Farr Zuend Amanda Mabhula Sarah Hoger Alana Lamont Kenzie Birse Alicia Berard Stuart McCorrister Garett Westmacott Al Leslie Vanessa Poliquin Renee Heffron Lyle R. McKinnon Adam D. Burgener 《PLoS pathogens》2020,16(12)
Alterations to the mucosal environment of the female genital tract, such as genital inflammation, have been associated with increased HIV acquisition in women. As the microbiome and hormonal contraceptives can affect vaginal mucosal immunity, we hypothesized these components may interact in the context of HIV susceptibility. Using previously published microbiome data from 685 women in the CAPRISA-004 trial, we compared relative risk of HIV acquisition in this cohort who were using injectable depot medroxyprogesterone acetate (DMPA), norethisterone enanthate (NET-EN), and combined oral contraceptives (COC). In women who were Lactobacillus-dominant, HIV acquisition was 3-fold higher in women using DMPA relative to women using NET-EN or COC (OR: 3.27; 95% CI: 1.24–11.24, P = 0.0305). This was not observed in non-Lactobacillus-dominant women (OR: 0.95, 95% CI: 0.44–2.15, P = 0.895) (interaction P = 0.0686). Higher serum MPA levels associated with increased molecular pathways of inflammation in the vaginal mucosal fluid of Lactobacillus-dominant women, but no differences were seen in non-Lactobacillus dominant women. This study provides data suggesting an interaction between the microbiome, hormonal contraceptives, and HIV susceptibility. 相似文献
54.
Akchheta Karki Joachim Vollbrecht Alexander J. Gillett Philipp Selter Jaewon Lee Zhengxing Peng Nora Schopp Alana L. Dixon Max Schrock Vojtech Ndady Franz Schauer Harald Ade Bradley F. Chmelka Guillermo C. Bazan Richard H. Friend Thuc‐Quyen Nguyen 《Liver Transplantation》2020,10(29)
Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor π? π interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs. 相似文献
55.
Lucas K. Smith Evgenia Verovskaya Gregor Bieri Alana M. Horowitz Saskia N. I. von Ungern‐Sternberg Karin Lin Peter Seizer Emmanuelle Passegu Saul A. Villeda 《Aging cell》2020,19(8)
The aged systemic milieu promotes cellular and cognitive impairments in the hippocampus. Here, we report that aging of the hematopoietic system directly contributes to the pro‐aging effects of old blood on cognition. Using a heterochronic hematopoietic stem cell (HSC) transplantation model (in which the blood of young mice is reconstituted with old HSCs), we find that exposure to an old hematopoietic system inhibits hippocampal neurogenesis, decreases synaptic marker expression, and impairs cognition. We identify a number of factors elevated in the blood of young mice reconstituted with old HSCs, of which cyclophilin A (CyPA) acts as a pro‐aging factor. Increased systemic levels of CyPA impair cognition in young mice, while inhibition of CyPA in aged mice improves cognition. Together, these data identify age‐related changes in the hematopoietic system as drivers of hippocampal aging. 相似文献
56.
57.
Wetlands Ecology and Management - Gas drilling into the Marcellus Shale play has been linked to environmental issues, including potential impacts on wildlife. In 2009, three separate accidents... 相似文献
58.
59.
Sarrawat Rehman Philippa E. Garner Jean E. Aaron Ruth K. Wilcox 《Computer methods in biomechanics and biomedical engineering》2013,16(11):1163-1169
The aim of this study was to investigate whether the predicted finite element (FE) stiffness of vertebral bone is altered when using images of preserved rather than fresh tissue to generate specimen-specific FE models. Fresh ovine vertebrae were used to represent embalmed (n = 3) and macerated dry-bone (n = 3) specimens and treated accordingly. Specimens were scanned pre- and post-treatment using micro-computed tomography. A constant threshold level derived from these images was used to calculate the respective bone volume fraction (BV/TV) from which the conversion factor validated for fresh tissue was used to determine material properties that were assigned to corresponding FE models. Results showed a definite change in the BV/TV between the fresh and the preserved bone. However, the changes in the predicted FE stiffness were not generally greater than the variations expected from assignment of loading and boundary conditions. In conclusion, images of preserved tissue can be used to generate FE models that are representative of fresh tissue with a tolerable level of error. 相似文献
60.
Joseph B Song Youssef S Tanagho Mohammed Haseebuddin Brian M Benway Alana C Desai Sam B Bhayani Robert S Figenshau 《Reviews in urology》2013,15(2):84-91
Retrieval of foreign bodies from the genitourinary system, most commonly inserted for sexual satisfaction or as a result of a psychiatric illness, can pose a significant surgical challenge. Due to their breadth of size, shape, and location within the genitourinary system, endoscopic management can be difficult. Here, we review the management of four cases of foreign object insertion into the genitourinary system and their outcomes and management.Key words: Foreign body insertion, Sounding, Genitourinary foreign object, Endoscopic extractionForeign objects within the genitourinary tract present a challenging urologic finding due to the diversity and breadth of presentation. Although many objects are easily removed, more complex approaches may be required depending on the size, shape, and location of the object.1,2 In this case series, we discuss the endoscopic management of four patients who presented with foreign bodies in the urethra. Two patients inserted beads into their genitourinary tract for the purpose of sexual stimulation and two patients had a history of psychiatric illness with multiple insertions of a diverse range of foreign objects. In all four cases, endoscopic management was successful in removing the objects, with no need for an open approach such as perineal urethrotomy or open cystostomy. In case 2, in which an open approach was attempted at an outside hospital, this open approach was associated with intraoperative complications. 相似文献