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151.
The effect of gonadotrophins with differing LH/FSH ratios on the secretion of the various species of inhibin in women receiving IVF 总被引:1,自引:0,他引:1
Fawzy M Harrison RF Knight PG Groome N Anderson A Robertson WR Lambert A 《Human reproduction (Oxford, England)》2001,16(6):1092-1097
We have measured secretory patterns of inhibin A, B, total alpha inhibin, pro-alphaC inhibin and oestradiol in women following pituitary suppression who were randomised into two groups to receive either urinary gonadotrophin (25:75 IU/ampoule of luteinizing hormone (LH) and follicle stimulating hormone (FSH; Normegon; n = 11) or recombinant (r)FSH (75 IU/ampoule of FSH alone, n = 16). The women were of similar age (approximately 33 years) and length of infertility (approximately 4 years) and had a normal endocrine evaluation. Plasma FSH, LH, oestradiol, inhibin A, B, pro-alphaC and total alpha inhibin were measured by immunoassay prior to and following gonadotrophin stimulation. Immunoactive FSH, LH and oestradiol blood concentrations following pituitary down regulation were similar in the two groups being <2.0, <3.6 IU/l and <82 pmol/l respectively. The units of FSH given (2230 versus 2764 IU; Normegon versus rFSH), duration of treatment (9.1 versus 9.4 days) and number of follicles of > or =14mm on the day of human chorionic gonadotrophin (HCG) administration (17 versus 14) were also similar. Inhibin A or B concentrations rose similarly during Normegon or rFSH administration, peaking at days 9-11. Total alpha and pro-alphaC inhibin concentrations were lower (P < 0.05) in the rFSH group during days 10 and 11 of treatment being 18.9 +/- 15.9 ng/ml (Normegon) and 4.6 +/- 2.8 ng/ml (rFSH) for total alpha inhibin and 8.5 +/- 6.8 ng/ml (Normegon) and 2.8 +/- 1.6 ng/ml (rFSH) for pro-alphaC inhibin on day 10. Overall, higher total alpha inhibin concentrations were associated with more mature follicles and oocytes, greater fertilization rates and better quality embryos. We conclude that inhibin A and B secretion was similar in both groups and is primarily controlled by FSH, whereas total alpha inhibin and pro-alphaC increased preferentially in the Normegon group over the rFSH group, indicating that they are, in part, stimulated by LH. 相似文献
152.
Lysosomal routing of Fc gamma RI from early endosomes requires recruitment of tyrosine kinases. 下载免费PDF全文
The high-affinity receptor for immunoglobulin G (Fc gamma RI) plays a central role in the clearance of immune complexes by mediating their internalization and delivery to lysosomes. In monocytic U937 cells, receptor internalization is independent of tyrosine kinase activity. However, the tyrosine kinase inhibitor, genistein, prevents further progress of the receptor to lysosomes and traps it in a sub-plasma membrane early endosome. Similarly, Fc gamma RI expressed in COS cells is able to internalize immune complexes but is unable to translocate to lysosomes. This suggests that Fc gamma RI, whose cytoplasmic tail is devoid of known signalling motifs, must recruit tyrosine kinases via its gamma-chain to achieve lysosomal delivery. We show that a chimera of the extracellular domain of Fc gamma RI and the cytoplasmic tail of the gamma-chain is both internalized and efficiently trafficked to lysosomes. Our study suggests that a key function of the gamma-chain is recruitment of tyrosine kinases to initiate the intracellular signalling pathways required to target Fc gamma RI following immune complex aggregation to lysosomes and not to initiate endocytosis per se. 相似文献
153.
Jennifer Janusz Caroline Harrison Cristina Boada Lisa Cordeiro Susan Howell Nicole Tartaglia Richard Boada 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(2):469-481
Few studies have systematically assessed executive functioning (EF) skills in boys with XXY, and these are limited by small samples and restricted EF assessment. This study used a broader battery of performance‐based measures as well as parent‐rating scales of EF in 77 boys and adolescents with XXY (mean age = 12.5 years), recruited from a clinical trial and an outpatient clinic. Exploratory factor analyses were used to create EF domains from performance‐based measures, and similar domains were measured using the Behavior Rating Inventory of Executive Function and Conners Parent‐Rating Scales. The boys with XXY showed a distinct EF profile, with the greatest deficit in attention and more moderate deficits in working memory, switching, and planning/problem solving. Parent ratings showed similar challenges, as well as impaired inhibition. Independent sample t‐tests showed no difference on performance measures between boys diagnosed or not diagnosed with attention‐deficit/hyperactivity disorder (ADHD), although parents of boys diagnosed with ADHD reported more difficulties. There were no differences on performance‐based tests between those diagnosed pre‐ and postnatally, although parents of postnatally diagnosed boys reported more metacognitive problems. Language deficits, cognition, and socio‐economic status did not account for EF deficits. 相似文献
154.
Housing type,housing location and mental health 总被引:2,自引:0,他引:2
P. McCarthy D. Byrne S. Harrison J. Keithley 《Social psychiatry and psychiatric epidemiology》1985,20(3):125-130
A number of studies have suggested a connection between the type of dwellings which people occupy and their mental health. People who live in flats are usually shown to be more prone to mental illness than those who live in houses. Those who live in high-rise accommodation are shown to be particularly vulnerable. These conclusions were examined by comparing rates on an indicator of psychological distress, in different dwelling types located in good and bad council housing areas. The results suggest that psychological distress is more closely associated with the location of a dwelling than with dwelling type. High-rise flats located on inner-city problem estates are associated with high levels of psychological distress, while low levels are found in similar dwelling types located in the suburbs. These findings are consistent when the effect of age, health, sex and household class are taken into consideration. 相似文献
155.
Russell EJ; Geremia GK; Johnson CE; Huckman MS; Ramsey RG; Washburn-Bleck J; Turner DA; Norusis M 《Radiology》1987,165(3):609-617
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes. 相似文献
156.
R Vijayanagar D Bognolo P Eckstein D Jeffery E Harrison J Kerpchar E Willard R Musunuru 《The Journal of cardiovascular surgery》1987,28(5):576-580
Questions regarding the relative safety and efficacy of internal mammary artery (IMA) grafts versus saphenous vein grafts (SVG) in patients with left main coronary artery disease (LMCAD) have not been specifically addressed in the literature. To elucidate this point, we analyzed 196 patients with LMCAD who underwent myocardial revascularization between January 1975 and December 1981, 98 by IMA and SVG and 98 by SVG, IMA was used most often to bypass the left anterior descending (LAD). Chi Square and "t" tests were performed on all demographic, cardiac and operative data comparing IMA to SVG. All results were non-significant, indicating that the two groups were comparable. Anginal pattern was progressive or unstable in 93%. IMA was used in 4 patients who were on intra-aortic balloon pump. The mean number bypass grafts per patient was 3.1. Postoperative complications were comparable for both groups, including early and late myocardial infarction. Overall operative mortality was 2.6%. Results of a survival analysis indicated no significant difference in the mortality rates of patients operated on by SVG versus IMA-SVG. Cumulative mortality rates at a mean followup of 20.5 months were 12.2% for SVG and 7.1% for IMA patients. Significant mortality risk factors were ejection fraction less than 55% (p less than 0.05); and perioperative myocardial infarction (p less than 0.001). Twenty-five patients with recurrent chest pain underwent repeat cardiac catheterization. This revealed 10 of 10 patent IMA grafts, 6 of 8 single patent SVG to LAD and 6 of 9 patent sequential vein grafts to the diagonal and LAD arteries.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
157.
158.
The toxicity of copper to the adult and early life stages of the freshwater clam,Corbicula manilensis 总被引:1,自引:0,他引:1
Florence L. Harrison John P. Knezovich David W. Rice Jr. 《Archives of environmental contamination and toxicology》1984,13(1):85-92
The copper sensitivity of adult and larval stages of the freshwater clamCorbicula manilensis was evaluated. In addition, copper concentrations were determined in adult clams exposed for 4 to 10 weeks to copper in a high-volume, flow-through bioassay. All bioassay systems utilized water that was low in total hardness and alkalinity.The response of the clams to copper depended on life stage. Copper sensitivity of larvae decreased markedly in successive developmental stages. LC5024's of veliger and juvenile larvae were 28 and 600 g Cu/L, respectively. The mortality of trochophore larvae exposed to 10 g Cu/L for one hr was 91.5%. The sensitivity to copper decreased with increased amounts of larval shell deposition.Adult clams were resistant to copper; the LC5096 was greater than 2,600 g Cu/L. By comparison, the incipient lethal concentration (ILC, was lowless than 10 g Cu/L. Adult clams accumulated more copper as concentrations in the water increased. Evidence was obtained for copper loss near or at death.Labile and total copper, as well as the coppercomplexing capacity, in the bioassay water were determined; the majority of copper was present as labile species. Toxicity was related to the quantities of labile copper in the water.This work was supported by the U.S. Nuclear Regulatory Commission (Memorandum of Understanding with the U.S. Department of Energy) and by the U.S. Department of Energy (contract number W-7405-ENG-48). 相似文献
159.
160.