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991.
Rene S. Hendriksen Pimlapas Leekitcharoenphon Matthew Mikoleit Jacob Dyring Jensen Rolf Sommer Kaas Louise Roer Heena B. Joshi Srirat Pornruangmong Chaiwat Pulsrikarn Gladys D. Gonzalez-Aviles E. Ascelijn Reuland Nashwan Al Naiemi Astrid Louise Wester Frank M. Aarestrup Henrik Hasman 《Journal of clinical microbiology》2015,53(2):677-680
One unreported case of extended-spectrum-beta-lactamase (ESBL)-producing Salmonella enterica serovar Typhi was identified, whole-genome sequence typed, among other analyses, and compared to other available genomes of S. Typhi. The reported strain was similar to a previously published strain harboring blaSHV-12 from the Philippines and likely part of an undetected outbreak, the first of ESBL-producing S. Typhi. 相似文献
992.
Mudit Chaand Kelly A. Miller Madeline K. Sofia Cory Schlesener Jacob W. A. Weaver Vibha Sood Michelle Dziejman 《Infection and immunity》2015,83(7):2862-2869
Vibrio cholerae is a genetically diverse species, and pathogenic strains can encode different virulence factors that mediate colonization and secretory diarrhea. Although the toxin-coregulated pilus (TCP) is the primary colonization factor in epidemic-causing V. cholerae strains, other strains do not encode the TCP and instead promote colonization via the activity of a type 3 secretion system (T3SS). Using the infant mouse model and T3SS-positive O39 serogroup strain AM-19226, we sought to determine which of 12 previously identified, T3SS-translocated proteins (Vops) are important for host colonization. We constructed in-frame deletions in each of the 12 loci in strain AM-19226 and identified five Vop deletion strains, including ΔVopM, which were severely attenuated for colonization. Interestingly, a subset of deletion strains was also incompetent for effector protein transport. Our collective data therefore suggest that several translocated proteins may also function as components of the structural apparatus or translocation machinery and indicate that while VopM is critical for establishing an infection, the combined activities of other effectors may also contribute to the ability of T3SS-positive strains to colonize host epithelial cell surfaces. 相似文献
993.
Summer E. Drake Samuel D. CRISH John C. George Raphaella Stimmelmayr J.G.M. Thewissen 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(7):1327-1335
We studied the histology and morphometrics of the hairs of bowhead whales (Balaena mysticetus). These whales are hairless except for two patches of more than 300 hairs on the rostral tip of the lower lip and chin, the rostral tip of the upper lip, and a bilateral row of approximately ten hairs caudal to the blowhole. Histological data indicate that hairs in all three of these areas are vibrissae: they show an outermost connective tissue capsule, a circumferential blood sinus system surrounding the hair shaft, and dense innervation to the follicle. Morphometric data were collected on hair diameters, epidermal recess diameters, hair follicle length, and external hair lengths. The main difference between the hairs in the different regions is that blowhole hairs have larger diameters than the hairs in the chin and rostrum regions. We speculate that the hair shaft thickness patterns in bowheads reflect functional specializations. Anat Rec, 298:1327–1335, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
994.
Catherine Racowsky Michael Vernon Jacob Mayer G. David Ball Barry Behr Kimball O. Pomeroy David Wininger William Gibbons Joseph Conaghan Judy E. Stern 《Journal of assisted reproduction and genetics》2010,27(8):437-439
Standardization of morphological assessment for embryo grading system was developed and is being implemented by the Society
for Assisted Reproductive Technology (SART). A recent European consensus conference of embryologists from Europe and America
is working toward adopting an embryo classification system modeled similarly to that of SART which, if adopted, would produce
a de facto international standard to aid cross border collaboration. 相似文献
995.
Jacob Farhi Avi Ben Haroush Nejmi Andrawus Haim Pinkas Onit Sapir Benjamin Fisch Jacob Ashkenazi 《Reproductive biomedicine online》2010,20(3):331-337
The study was designed to evaluate the isolated effect of high serum oestradiol concentration on human chorionic gonadotrophin (HCG) day in IVF cycles on endometrial receptivity and placentation. A retrospective cohort included all women attending the IVF unit in 2006 and 2007, with the best prognosis to achieve pregnancy: age (<38 years), less than three IVF cycles, transfer of two highest grade embryos and no evidence of factors known to impair implantation or that are associated with increased risk of pregnancy complications. The total included 280 patients were categorized into three groups according to their serum oestradiol concentration on HCG day: group 1, oestradiol <5000 pmol/l, group 2, oestradiol in the range 5000–10,000 pmol/l and group 3, oestradiol in the range of 10,000–15,000 pmol/l. No significant differences were found between the groups in implantation, pregnancy and abortion rates. The high oestradiol group was characterized by high rate (20.8%) of pregnancy complications related to abnormal placentation – fetal growth restriction, pregnancy-induced hypertension and abnormal implantation of the placenta. Hence, the decision to perform embryo transfer in high-responder patients should take into consideration both possible risks of ovarian hyperstimulation syndrome and pregnancy complications related to abnormal placentation. 相似文献
996.
Erik J. Giltay Yuliya A. Tishova George J. Mskhalaya Louis J.G. Gooren Farid Saad Svetlana Y. Kalinchenko 《The journal of sexual medicine》2010,7(7):2572-2582
IntroductionLow testosterone levels in men are associated with the metabolic syndrome (MetS) as well as with depressive symptoms, low vitality, and sexual dysfunction.AimTo assess the effects of testosterone administration on these subjective symptoms, which have not extensively been studied in hypogonadal men with the MetS.Main Outcome MeasuresThe Beck Depression Inventory (BDI-IA), Aging Males' Symptoms (AMS) scale, and International Index of Erectile Function 5-item (IIEF-5) scale at baseline, 18 and 30 weeks were analysed using multilevel analysis.MethodsIn a randomized, placebo-controlled, double-blind, phase III trial (ClinicalTrials.gov identifier: NCT00696748), 184 men suffering from both the MetS and hypogonadism were included. They were treated for 30 weeks with either parenteral testosterone undecanoate (TU; 1,000 mg IM TU, at baseline, and after 6 and 18 weeks; Nebido®) or placebo injections, 105 (92.9%) men receiving TU and 65 (91.5%) receiving placebo completed the 30-week trial.ResultsThe 184 men were aged mean 52.1 years old (standard deviation [SD] 9.6; range 35–69), with a mean body mass index of 35.5 kg/m2 (SD 6.7; range 25.1–54.8), and a mean total testosterone level of 8.0 nmol/L (SD 4.0). There were significant improvements in BDI-IA (mean difference vs. placebo after 30 weeks: ?2.5 points; 95% confidence interval [CI]: ?0.9; ?4.1; P = 0.003), AMS (?7.4 points; 95% CI: ?4.3; ?10.5; P < 0.001), and IIEF-5 (+3.1 points; 95% CI: +1.8; +4.4; P < 0.001). The effects on the BDI-IA, AMS, and IIEF-5 were strongest in men with baseline total testosterone levels <7.7 mmol/L (i.e., median value).ConclusionsTU administration may improve depressive symptoms, aging male symptoms and sexual dysfunction in hypogonadal men with the MetS. The beneficial effects of testosterone were most evident in men with the lowest baseline total testosterone levels. Giltay EJ, Tishova YA, Mskhalaya GJ, Gooren LJG, Saad F, and Kalinchenko SY. Effects of testosterone supplementation on depressive symptoms and sexual dysfunction in hypogonadal men with the metabolic syndrome. 相似文献
997.
998.
Wiebe R. Patberg Arie Nijmeijer Jan K. Schut Adrian Versprille Jacob P. Zock Willem G. Zijlstra 《Pflügers Archiv : European journal of physiology》1992,421(2-3):280-282
In ten vagus nerves the effect of local cooling on the compound action potential was studied in the temperature range of 34 to 0 °C in spontaneously breathing, anaesthetized rabbits. The mean temperature at which the myelinated (A) fibres were completely blocked, was 10.2±2.4 °C (mean ± S.D.). In nine nerves, local vagus cooling to 0 °C failed to block all non-myelinated (C) fibres. In one nerve, total blocking occurred at 2.0 °C. We conclude that in the rabbit, the earlier found increase in tonic activity of the diaphragm following lung inflation or deflation during bilateral local vagus cooling to a temperature between 8 and 0 °C is due to afferent impulses in vagal C fibres. 相似文献
999.
We describe the production of mouse monoclonal antibodies specific for the human TcR using as the immunogen transfected murine T-cell hybridoma cells coexpressing mouse CD3 with human Jurkat TcR alpha and beta chains. The shortage of monoclonal antibodies (mAbs) specific for the human TcR-V alpha and V beta families reflects the difficulties in their production by conventional methods using whole human T cells or purified soluble receptors as immunogens. As an alternative strategy to circumvent these difficulties, we have generated a transfected mouse T-cell line expressing a human (Jurkat) TcR alpha beta dimer in a complex with mouse CD3. The parental mouse T-cell line, TG40, is a cell surface TcR-negative, cytoplasmic CD3-positive variant of the mouse T-cell hybridoma 2B4. The human-TcR alpha beta expressing mouse transfectant was used to immunize mice with the same genetic background as the parent mouse T-cell line, and a human TcR-specific response was successfully achieved. MAb-producing hybridomas were generated by fusing spleen cells from the immunized mice with the mouse myeloma cell line NSO. Of 124 hybridoma supernatants screens, 72 showed reactivity to the human T-cell line Jurkat. Twenty-four of the hybridomas producing human (Jurkat) TcR-specific antibodies were cloned and screened for reactivity to Jurkat TcR. Several IgG2b and IgM mAbs specific for the Jurkat T cell line were selected on the basis of their ability to modulate surface CD3 expression on Jurkat cells. Most of the antibodies do not stain other TcR-expressing human T cell leukemia cell lines, implying specificity for the variable domains of the Jurkat TcR.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
Gyrgy Stuber Susanne Modrow Petter Hglund Lars Franksson John Elvin Hans Wolf Klas Krre George Klein 《European journal of immunology》1992,22(10):2697-2703
Earlier findings indicate that peptides can affect the expression of major histocompatibility complex (MHC) class I molecules on the surface of cells with defective peptide loading mechanism. We have used peptide induced increase of class I antigen expression to assess peptide interaction with MHC class I molecules. A panel of 41 overlapping synthetic peptides derived from the human immunodeficiency virus-1 (HIV-1) gag protein and 33 nonoverlapping peptides from Epstein-Barr virus (EBV) proteins EBNA-1, 2, 3, 4, 5, 6, LMP, BZLF2, BILF2, BSLF2, BALF4 and BcLF1 was assessed for the ability to enhance the expression of HLA-A2.1, H-2Db, Kb and Dd on the murine RMA-S and human 721.174/T2 (.174/T2) lines by indirect immunofluorescence. Considering doubling of the fluorescence intensity in the peptide-treated samples as positivity, 6 of 39 HIV and 1 of 32 EBV peptides were found to bind to A2.1, 6 of 39 HIV gag and 7 of 16 EBV peptides to Db, 8 of 39 HIV gag and 5 of 16 EBV peptides to Kb and 2 of 39 HIV gag and 1 of 17 EBV peptides to Dd. The sensitivity of the method is comparable to the in vitro class I assembly assay with conformation-dependent monoclonal antibody and is more discriminating than the solid-phase assay. Due to its simplicity this method can also serve for testing large peptide panels for binding capacity to various class I molecules. Moreover, the method provides information about the relevance of in vitro tests for class I assembly in living cells. 相似文献