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排序方式: 共有156条查询结果,搜索用时 31 毫秒
61.
Ray Garry Jayne Fountain Su Mason Vicky Napp Julia Brown Jeremy Hawe Richard Clayton Jason Abbott Graham Phillips Mark Whittaker Richard Lilford Stephen Bridgman 《BMJ (Clinical research ed.)》2004,328(7432):129
Objective To compare the effects of laparoscopic hysterectomy and abdominal hysterectomy in the abdominal trial, and laparoscopic hysterectomy and vaginal hysterectomy in the vaginal trial.Design Two parallel, multicentre, randomised trials.Setting 28 UK centres and two South African centres.Participants 1380 women were recruited; 1346 had surgery; 937 were followed up at one year.Primary outcome Rate of major complications.Results In the abdominal trial laparoscopic hysterectomy was associated with a higher rate of major complications than abdominal hysterectomy (11.1% v 6.2%, P = 0.02; difference 4.9%, 95% confidence interval 0.9% to 9.1%) and the number needed to treat to harm was 20. Laparoscopic hysterectomy also took longer to perform (84 minutes v 50 minutes) but was less painful (visual analogue scale 3.51 v 3.88, P = 0.01) and resulted in a shorter stay in hospital after the operation (3 days v 4 days). Six weeks after the operation, laparoscopic hysterectomy was associated with less pain and better quality of life than abdominal hysterectomy (SF-12, body image scale, and sexual activity questionnaires).In the vaginal trial we found no evidence of a difference in major complication rates between laparoscopic hysterectomy and vaginal hysterectomy (9.8% v 9.5%, P = 0.92; difference 0.3%, -5.2% to 5.8%), and the number needed to treat to harm was 333. We found no evidence of other differences between laparoscopic hysterectomy and vaginal hysterectomy except that laparoscopic hysterectomy took longer to perform (72 minutes v 39 minutes) and was associated with a higher rate of detecting unexpected pathology (16.4% v 4.8%, P = < 0.01). However, this trial was underpowered.Conclusions Laparoscopic hysterectomy was associated with a significantly higher rate of major complications than abdominal hysterectomy. It also took longer to perform but was associated with less pain, quicker recovery, and better short term quality of life. The trial comparing vaginal hysterectomy with laparoscopic hysterectomy was underpowered and is inconclusive on the rate of major complications; however, vaginal hysterectomy took less time. 相似文献
62.
Hernan Aviles Tesfaye Belay Kimberly Fountain Monique Vance Buxiang Sun Gerald Sonnenfeld 《Journal of applied physiology》2003,95(2):491-496
Previous studies have demonstrated that resistance to infection is decreased in Swiss Webster female mice maintained in the hindlimb-unloading model (Aviles H, Belay T, Fountain K, Vance M, and Sonnenfeld G. J Appl Physiol 95: 73-80, 2003; Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 110: 262-268, 2002). This is a model of some of the aspects of spaceflight conditions, including lack of load bearing on hindlimbs and a fluid shift to the head. Active hexose correlated compound (AHCC), extracted from Basidiomycete mushrooms, has been shown to induce enhancement of immune responses, including enhanced natural killer activity. In the present study, AHCC was orally administered to mice to determine whether the treatment could decrease immunosuppression and mortality of mice maintained in the hindlimb-unloaded model and infected with Klebsiella pneumoniae. The results of the present study showed that administration of AHCC by gavage for 1 wk (1 g/kg body wt) before suspension and throughout the 10-day suspension period yielded significant beneficial effects for the hindlimb-unloaded group, including 1). decreased mortality, 2). increased time to death, and 3). increased ability to clear bacteria. The results suggest that AHCC can decrease the deleterious effects of the hindlimb-unloading model on immunity and resistance to infection. 相似文献
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65.
Polyribosome formation and protein synthesis in imbibed but dormant lettuce seeds 总被引:6,自引:4,他引:2 下载免费PDF全文
Dormancy is maintained in Grand Rapids lettuce (Lactuca sativa) seeds imbibed on water in darkness at 25 C. Polyribosome formation and protein synthesis occur early in the imbibition phase and considerable polysomal material is also present after 24 and 48 hours, even though the seeds have failed to germinate. Incorporation of labeled leucine into protein following a 24-hour preincubation period shows that these polysomes are active in protein synthesis. 相似文献
66.
Distance,environmental and substrate factors impacting recovery of bryophyte communities after harvesting 下载免费PDF全文
Thomas P. Baker Gregory J. Jordan Nicholas M. Fountain‐Jones Jayne Balmer Patrick J. Dalton Susan C. Baker 《应用植被学》2018,21(1):64-75
Aims
Bryophyte re‐colonization after disturbance is largely governed by environmental conditions within disturbed forests. In particular, distance to a forest edge is an important predictor of bryophyte community re‐colonization, through either direct constraints, such as dispersal limitation, or indirectly by altering environmental conditions. This study examines a range of factors – environmental, distance to an edge, substrate specific environment or local‐level environment – to determine which are important in the re‐colonization of bryophyte communities after forest harvesting. As bryophyte communities vary with the particular substrate inhabited, responses were examined across four substrates (rock, exposed roots, ground and CWD).Location
Tasmanian southern forests, Australia.Methods
Bryophyte composition was examined on four substrates (ground, coarse wood debris, exposed roots, rocks) within three ages (~7, ~27 and ~45 years post‐disturbance) of harvested wet eucalypt forest. Re‐colonization success of bryophyte communities was determined by comparing communities in regeneration forest to mature forest communities using axis scores from one‐dimensional constrained ordination. The importance of various environmental conditions for re‐colonization success was then modelled. Finally, path analysis was used to determine whether the impact of distance to a forest edge was meditated through its effects on key environmental variables.Results
Multiple environmental factors impacted re‐colonization of mature bryophyte communities. Local‐level conditions such as microclimate (temperature, humidity and VPD) and LAI were the most important in determining re‐colonization across substrates. Path analysis showed that distance to a forest edge had a significant impact on re‐colonization success, but only a relatively small part of this was mediated through its impact on environmental factors.Conclusions
Bryophyte re‐colonization is driven by a combination of microclimate conditions and factors related to distance from a forest edge (most likely dispersal distance). While some substrate‐specific factors impact bryophyte re‐colonization success, the consistent impact of local environmental factors across substrates suggests that harvesting management strategies that develop more ‘mature’ microclimate conditions and increase proximity to nearby mature forest patches will be beneficial for all bryophytes communities. As bryophyte re‐colonization was correlated with temporally dynamic environmental conditions, we suggest that forest age needs to be considered in future work. 相似文献67.
Adipose tissue contains self-renewing multipotent cells termed mesenchymal stromal cells. In situ, these cells serve to expand adipose tissue by adipogenesis, but their multipotency has gained interest for use in tissue regeneration. Little is known regarding the repertoire of receptors expressed by adipose-derived mesenchymal stromal cells (AD-MSCs). The purpose of this study was to undertake a comprehensive analysis of purinergic receptor expression. Mesenchymal stromal cells were isolated from human subcutaneous adipose tissue and confirmed by flow cytometry. The expression profile of purinergic receptors was determined by quantitative real-time PCR and immunocytochemistry. The molecular basis for adenine and uracil nucleotide-evoked intracellular calcium responses was determined using Fura-2 measurements. All the known subtypes of P2X and P2Y receptors, excluding P2X2, P2X3 and P2Y12 receptors, were detected at the mRNA and protein level. ATP, ADP and UTP elicited concentration-dependent calcium responses in mesenchymal cells (N?=?7–9 donors), with a potency ranking ADP (EC50 1.3 ± 1.0 μM)?>?ATP (EC50 2.2 ± 1.1 μM)?=?UTP (3.2 ± 2.8 μM). Cells were unresponsive to UDP (<?30 μM) and UDP-glucose (<?30 μM). ATP responses were attenuated by selective P2Y2 receptor antagonism (AR-C118925XX; IC50 1.1 ± 0.8 μM, 73.0?±?8.5% max inhibition; N?=?7 donors), and UTP responses were abolished. ADP responses were attenuated by the selective P2Y6 receptor antagonist, MRS2587 (IC50 437 ± 133nM, 81.0?±?8.4% max inhibition; N?=?6 donors). These data demonstrate that adenine and uracil nucleotides elicit intracellular calcium responses in human AD-MSCs with a predominant role for P2Y2 and P2Y6 receptor activation. This study furthers understanding about how human adipose-derived mesenchymal stromal cells can respond to external signalling cues. 相似文献
68.
Fine structure DNA mapping studies of the chromosomal region harboring the genetic defect in neurofibromatosis type 1 总被引:1,自引:0,他引:1 下载免费PDF全文
P. O''''Connell R. J. Leach D. H. Ledbetter R. M. Cawthon M. Culver J. R. Eldridge A.-K. Frej T. R. Holm E. Wolff M. J. Thayer A. J. Schafer J. W. Fountain M. R. Wallace F. S. Collins M. H. Skolnick D. C. Rich R. E. K. Fournier B. J. Baty J. C. Carey M. F. Leppert G. M. Lathrop J.-M. Lalouel R. White 《American journal of human genetics》1989,44(1):51-57
To better map the location of the von Recklinghausen neurofibromatosis (NF1) gene, we have characterized a somatic cell hybrid designated 7AE-11. This microcell-mediated, chromosome-transfer construct harbors a centromeric segment and a neo-marked segment from the distal long arm of human chromosome 17. We have identified 269 cosmid clones with human sequences from a 7AE-11 library and, using a panel of somatic cell hybrids with a total of six chromosome 17q breakpoints, have mapped 240 of these clones on chromosome 17q. The panel included a hybrid (NF13) carrying a der(22) chromosome that was isolated from an NF1 patient with a balanced translocation, t(17;22) (q11.2;q11.2). Fifty-three of the cosmids map into a region spanning the NF13 breakpoint, as defined by the two closest flanking breakpoints (17q11.2 and 17q11.2-q12). RFLP clones from a subset of these cosmids have been mapped by linkage analysis in normal reference families, to localize the NF1 gene more precisely and to enhance the potential for genetic diagnosis of this disorder. The cosmids in the NF1 region will be an important resource for testing DNA blots of large-fragment restriction-enzyme digests from NF1 patient cell lines, to detect rearrangements in patients' DNA and to identify the 17;22 NF1 translocation breakpoint. 相似文献
69.
70.
J W Fountain M Karayiorgou D Taruscio S L Graw A J Buckler D C Ward N C Dracopoli D E Housman 《Genomics》1992,14(1):105-112
A region of chromosome 9, surrounding the interferon-beta (IFNB1) locus and the interferon-alpha (IFNA) gene cluster on 9p13-p22, has been shown to be frequently deleted or rearranged in a number of human cancers, including leukemia, glioma, non-small-cell lung carcinoma, and melanoma. To assist in better defining the precise region(s) of 9p implicated in each of these malignancies, a combined genetic and physical map of this region was generated using the available 9p markers IFNB1, IFNA, D9S3, and D9S19, along with a newly described locus, D9S126. The relative order and distances between these loci were determined by multipoint linkage analysis of CEPH (Centre d'Etude du Polymorphisme Humain) pedigree DNAs, pulsed-field gel electrophoresis, and fluorescence in situ hybridization. All three mapping approaches gave concordant results and, in the case of multipoint linkage analysis, the following gene order was supported for these and other closely linked chromosome 9 markers present in the CEPH database: pter-D9S33-IFNB1/IFNA-D9S126-D9S3-D9S19 -D9S9/D9S15-ASSP3-qter. This map serves to extend preexisting chromosome 9 maps (which focus primarily on 9q) and also reassigns D9S3 and D9S19 to more proximal locations on 9p. 相似文献