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141.
Methods in Cell Science - 相似文献
142.
James CA Holtzman NA Hadley DW 《American journal of medical genetics. Part C, Seminars in medical genetics》2003,(1):60-69
Although recent research has investigated the attitudes of parents, professionals, and adult siblings toward carrier testing of minors, no studies have focused on the experiences of minor siblings of individuals with X-linked and autosomal recessive conditions. To explore adolescent sisters' perceptions of their reproductive risks, attitudes toward carrier testing, and resources for information and support, we interviewed 14 parents and 9 sisters (ages 12-15) of males with chronic granulomatous disease (CGD), a primary immunodeficiency disorder inherited in both an X-linked recessive and autosomal recessive fashion. Our semistructured telephone interviews were audiotaped, transcribed, and subjected to template analysis (a common qualitative methodology). Girls were all aware that CGD is an inherited condition and each had made an assessment of her reproductive risk. All girls considered their parents to be their best source of information and support, but girls had trouble initiating discussions for fear of upsetting their parents. All girls and parents considered eventual carrier testing vital for reproductive decision-making and relationship-building. However, girls favored carrier testing at a later age and expressed more concerns about psychological risks associated with testing than did their parents. When faced with the hypothetical situation of being offered carrier testing "tomorrow," half of the parents and untested daughters disagreed on the desirability of the test, with parents more likely to favor testing. Including adolescent sisters in family-based genetic counseling that provides an opportunity for age-appropriate discussion of inheritance and the timing, risks, and benefits of carrier testing would be beneficial to them. Published 2003 Wiley-Liss, Inc. 相似文献
143.
Lehmann A Katayama S Harrison C Dhut S Kitamura K McDonald N Toda T 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(5):367-382
Skp1 is a central component of the E3 ubiquitin ligase SCF (Skp1-Cullin-1-F-box). It forms an adapter bridge between Cullin-1 and the substrate-determining component, the F-box protein. In order to establish the role of Skp1, a temperature sensitive (ts) screen was carried out using mutagenic PCR (polymerase chain reaction) and 9 independent ts mutants were isolated. Mapping the mutated residues on the 3-D structure of human Skp1 suggested that the mutants would be compromised in binding to F-box proteins but not Cullin-1 (Pcu1). In order to assess the binding properties of ts Skp1, 12 F-box proteins and Pcu1 were epitope-tagged, and co-immunoprecipitation performed. This systematic analysis showed that ts Skp1 retains binding to Pcu1. However, binding to three specific F-box proteins, essential Pof1, Pof3 involved in maintaining genome integrity, and nonessential Pof10, was reduced. skp1ts cells exhibit a G2 cell cycle delay, which is attributable to activation of the DNA damage checkpoint. Intriguingly, contrary to pof3 mutants, in which this checkpoint is required for survival, checkpoint abrogation in skp1(ts) suppresses a G2 delay and furthermore almost rescues the ts phenotype. The activation mechanism of the DNA damage checkpoint therefore differs between pof3Delta and skp1(ts), implicating a novel role for Skp1 in the checkpoint-signalling cascade. 相似文献
144.
Leukocyte-reduced transfusions in cardiac surgery results of an implementation trial 总被引:3,自引:0,他引:3
Blumberg N Heal JM Cowles JW Hicks GL Risher WH Samuel PK Kirkley SA 《American journal of clinical pathology》2002,118(3):376-381
An implementation trial of leukocyte-reduced transfusions in cardiac surgery (primary coronary artery bypass graft and valve replacement) was performed from July to December 1998; comparisons were made with data from the same period in 1997. Patients from both periods were similar in important preoperative and intraoperative variables (age, sex, weight, number of units of RBCs transfused, ejection fraction). The mean total number of complications was statistically significantly decreasedfrom 0.26 complications per patient in the non-leukocyte-reduced to 0.19 in the leukocyte-reduced recipients. Overall, the mean +/- ISD costs of care per patient decreasedfrom 1997 ($27,615 +/- $33,973) to 1998 ($27,038 +/- $24,107). Mean costs decreased $1,700 per patient for recipients of leukocyte-reduced blood in 1998 compared with recipients of non-leukocyte-reduced blood in 1997 Mean costs increased $4,000 per patient in patients who did not receive transfusions in 1998 compared with 1997. Hospitalization costs decreased when leukocyte-reduced transfusions were implemented for patients undergoing cardiac surgery in our institution. Implementation of leukocyte reduction may be cost neutral or cost saving in at least some settings. 相似文献
145.
146.
Phosphorylated KDR is expressed in the neoplastic and stromal elements of human renal tumours and shuttles from cell membrane to nucleus 总被引:3,自引:0,他引:3
Fox SB Turley H Cheale M Blázquez C Roberts H James N Cook N Harris A Gatter K 《The Journal of pathology》2004,202(3):313-320
Vascular endothelial growth factor (VEGF)-A is an important angiogenic factor in establishing the vasculature in renal cell carcinomas (RCCs). Since little is known about VEGF signalling in RCCs, the profile of phosphorylated KDR (pKDR) has been investigated and the intracellular location of the receptor has been examined in the present study. Using two monoclonal antibodies raised against the phosphorylated KDR epitopes (Y1059 and Y1214) known to mediate different VEGF functions, together with a commercial anti-KDR antibody and immunohistochemistry, the expression of pKDR was investigated in a series of normal (n = 25) and neoplastic kidneys (n = 54; clear cell n = 35; papillary n = 10; oncocytomas n = 8). pKDR was present in many tissue elements of both normal and neoplastic renal tissues, with strong expression in the cell membrane, cytoplasm, and nuclei of normal kidney and tumour cells, as well as endothelial cells in tumours of all histological types. Patterns and intensity were similar using both anti-pKDR antibodies. There was no significant correlation in clear cell carcinomas between pKDR expression and age (p = 0.57), tumour size (p = 0.2), gender (p = 0.59), grade (p = 0.2) or histological type (p = 0.36). To delineate further the intracellular processing that might account for the cellular distribution, confocal microscopy was also performed. Antibodies to the different phosphorylated epitopes demonstrated different intracellular staining patterns. This study shows that pKDR is present in a wide variety of renal tumours, suggesting that anti-VEGF therapy might have direct effects on tumour cells. It further suggests that cells traffic pKDR depending on the precise KDR tyrosines that are autophosphorylated in a manner that enables receptor activation to result in different functions. 相似文献
147.
Drinking induced in rats by systemic isoproterenol treatment is markedly attenuated after bilateral nephrectomy. The present experiments demonstrate that the hypotension produced by iso-proterenol treatment was more profound, and lasted much longer, in nephrectomized rats than in intact animals. When arterial blood pressure was partially elevated by central administration of angiotensin II or carbachol (Experiment 1) or by intraarterial infusion of epinephrine (Experiment 2), drinking behavior was restored in the nephrectomized animals and their water intakes approximated the amounts consumed by intact rats given isoproterenol. In general, an inverted U-shaped curve was found to define the relation between blood pressure and water intake in rats after isoproterenol treatment. Drinking was most probable when mean arterial blood pressures were in the range of 70–85 mm Hg, whereas rats were unlikely to drink when blood pressures were much below or above this range. These findings indicate that isoproterenol-induced thirst is not dependent on a renal dipsogen, and suggest instead that the hypersecretion of renin that occurs in intact rats is simply permissive of drinking behavior by modulating the hypotensive effects of the drug treatment. 相似文献
148.
Shankaran S Laptook AR Ehrenkranz RA Tyson JE McDonald SA Donovan EF Fanaroff AA Poole WK Wright LL Higgins RD Finer NN Carlo WA Duara S Oh W Cotten CM Stevenson DK Stoll BJ Lemons JA Guillet R Jobe AH;National Institute of Child Health Human Development Neonatal Research Network 《The New England journal of medicine》2005,353(15):1574-1584
149.
Variations in the anatomy of the abdominal aorta and its branches are of interest as vessel geometry not only determines flow
dynamics, but is also crucial in the pathogenesis of vascular disease. The relationship between the anterior visceral and
renal arteries is important when undertaking diagnostic arteriography and endovascular interventions. To examine these relationships,
the length of the abdominal aorta was determined and measurements taken of the position of origin of the celiac artery, superior
mesenteric artery (SMA), inferior mesenteric artery (IMA) and renal arteries, as well as the three-dimensional projection
of each vessel from the aorta. The mean level of bifurcation of the aorta was at the lower third of the body of L4, with the
celiac artery, SMA, renal arteries and IMA arising at the level of the T12/L1 intervertebral disc, upper third of the body
of L1, lower third of the body of L1 and lower third of the body of L3, respectively. The horizontal projection of the celiac
artery, SMA and IMA was to the left of the midline; in the sagittal plane, the celiac artery and SMA projected anteriorly
and the IMA posteriorly; in the coronal plane all vessels projected inferiorly, with the SMA to the right and the IMA to the
left. The celiac artery, SMA and both renal arteries all arise from the proximal half of the abdominal aorta within 45 mm
of each other, with the origins of the renal arteries being remarkably consistent. It is concluded that the celiac artery
and SMA are both useful landmarks for determining the position of the renal arteries. 相似文献
150.
Tatyana B. Nesterova Sarah M. Duthie Nina A. Mazurok Al'bina A. Isaenko Nadezhda V. Rubtsova Suren M. Zakian Neil Brockdorff 《Chromosome research》1998,6(1):41-48
Comparative mapping of X-linked genes has progressed rapidly since Ohno's prediction that genes on the X chromosome should be conserved as a syntenic group in all mammals. Although several conserved blocks of homology between human and mouse have been discovered, rearrangements within the X chromosome have also been characterized. More recently, some exceptions to Ohno's law have been reported. We have used fluorescence in situ hybridization (FISH) to map five genes, Gla, G6pd, Hprt, Pgk1 and Xist, to two of the largest conserved segments of X material in five members of the genus Microtus (grey vole) and show that vole X chromosomes demonstrate greater homology to human than to mouse. Cytogenetic analysis indicates a relatively high frequency of rearrangement during vole evolution, although certain blocks of homology appear to be highly conserved in all species studied to date. On this basis we were able to predict the probable location of the rat X inactivation centre (Xic) based solely on high-resolution G-banding. Our prediction was then confirmed by mapping the rat Xist gene by FISH. The possible significance of conserving long-range chromosome structure in the vicinity of the Xic is discussed with respect to the mechanism of X inactivation. 相似文献