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21.
Vollenhoven B.J.; Herington A.C.; Healy D.L. 《Human reproduction (Oxford, England)》1994,9(2):214-219
The primary objective of this study was to suggest a possiblemechanism of action of luteinizing hormone-releasing hormoneagonist (LHRHa) on fibroids. This was performed by investigatinginsulin-like growth factor (IGF)-I, IGF-II and IGF binding protein(IGFBP)-1, -2 and -3 mRNA expression in uterine fibroids fromwomen rendered hypo-oestrogenic by LHRHa, using Northern blotanalysis. Nine women with fibroids, who were rendered hypo-oestrogenicfrom at least 4 months pretreatment with LHRHa therapy priorto undergoing myomectomy were investigated. Our results showedthat IGF-I, IGF-II, IGFBP-2 and -3 mRNAs were expressed in uterinefibroids, and that IGFBP-1 mRNA or protein was not detectedin fibroids. Western ligand blotting showed the presence ofIGFBP-2 and -3 proteins, and when compared with a group of womenwith fibroids not treated with LHRHa (B.J.Vollenhoven et al.,1993, J. Clin. Endocrinol Metab., 76, 11061110) we foundthat there was no difference in the relative abundance for eachof the factors between the two groups of women. Therefore, LHRHaact to decrease fibroid size via induction of a hypo-oestrogenicstate rather than by changes in the IGFs and their IGFBPs. 相似文献
22.
Krushkal J; Xiong M; Ferrell R; Sing CF; Turner ST; Boerwinkle E 《Human molecular genetics》1998,7(9):1379-1383
Elevated blood pressure is an important risk factor for renal-, cerebro-
and cardiovascular diseases. We used an efficient discordant sib-pair
ascertainment scheme to investigate the impact of the distal end of the
long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing
genes for the alpha1B and beta2 adrenergic receptors and the dopamine
receptor type 1A on variation of systolic blood pressure in young
Caucasians. We measured eight highly polymorphic markers spanning this
positional candidate gene-rich region in 427 individuals from 55
three-generation pedigrees containing 69 discordant sibling pairs, and
calculated multipoint identity by descent (MIBD) probabilities. The results
of genetic linkage and association tests indicate that the region between
markers D5S2093 and D5S462 is significantly linked to one or more
polymorphic genes influencing interindividual variation in systolic blood
pressure levels. Since the alpha1B adrenergic receptor and dopamine
receptor type 1A genes are located close to these markers, these data
suggest that genetic variation in one or both of these G protein-coupled
receptors, which participate in the control of vascular tone, plays an
important role in influencing interindividual variation in systolic blood
pressure levels.
相似文献
23.
Ng ML Healy DL Rajna A Fullerton M O'Grady C Funder JW 《The Malaysian journal of pathology》1996,18(1):59-63
Immunoreactive adrenocorticotropin (ACTH), beta-endorphin (BEP) and corticotropin-releasing factor (CRF) were detected in human term placenta obtained from elective Caesarian surgery. The concentrations of ACTH, BEP and CRF in placenta detected by radioimmunoassay (RIA) were 2.83 +/- 0.36, 0.52 +/- 0.05 and 0.56 +/- 0.15 ng/g wet weight of tissue respectively. Pro-opiomelanocortin (POMC) peptides were also detected in the amnion and chorion membranes and in the decidua. The concentrations of ACTH were 1.72 +/- 0.20, 4.43 +/- 0.39 and 5.80 +/- 0.17 ng/g and the levels of BEP were 0.42 +/- 0.18, 0.65 +/- 0.20 and 3.66 +/- 1.10 ng/g in the amnion, chorion and decidua respectively. In contrast to placenta, immunoreactive CRF was not detected in the amnion, chorion and decidua. Immunoreactive N-acetylated BEP was also not detected in all the placental subfractions. Comparison of the amounts of both ACTH and BEP in the various placental components indicated the following distribution: decidua > chorion > placenta > amnion. In decidua, POMC peptides were present in an equi-molar ratio but in the other three placental fractions, ACTH levels were three to five-fold higher than BEP. In immunohistochemical studies, only a positive staining for ACTH was obtained for decidua. Our results confirm the presence of POMC peptides and CRF in placenta and their physiological roles in pregnancy and parturition. 相似文献
24.
Alireza Rezania Carson H. Thomas Kevin E. Healy 《Annals of biomedical engineering》1997,25(1):190-203
Patterned surfaces with alternating regions of amino silanes [N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane (EDS)] and alkyl silanes [dimethyldichlorosilane (DMS)] have been used to alter
the kinetics of spatial distribution of cellsin vitro. In particular, we have previously observed the preferential spatial distribution of bone cells on the EDS regions of EDS/DMS
patterned surfaces (10). In this study, we examined whether the mechanism of spatial distribution of cells on the EDS regions
was adhesion mediated. Homogeneous layers of EDS and DMS were immobilized on quartz substrates and characterized by contact
angle, X-ray photoelectron spectroscopy, and spectroscopic ellipsometry. The strength of bone cell attachment to the modified
substrates was examined using a radial flow apparatus, within either 20 min or 2 hr of cell incubation in the presence of
serum. A Weibull distribution was chosen to characterize the strength of cell-substratum adhesion. Within 20 min of cell exposure,
the strength of adhesion was significantly larger on EDS and clean surfaces, compared with DMS surfaces (p<0.0001). Within 2 hr of cell incubation, there was no statistical difference between the strength of cell adhesion to EDS,
DMS, and clean surfaces. The results of this study suggest that the surface chemistry mediates adhesion-based spatial cell
arrangement through a layer of adsorbed serum proteins. 相似文献
25.
G R Istre K Kreiss R S Hopkins G R Healy M Benziger T M Canfield P Dickinson T R Englert R C Compton H M Mathews R A Simmons 《The New England journal of medicine》1982,307(6):339-342
From June 1978 through December 1980, at least 36 cases of amebiasis occurred in persons who had had colonic-irrigation therapy at a chiropractic clinic in western Colorado. Of 10 persons who required colectomy, six did. Of 176 persons who had been to the clinic in the last four months of 1980, 80 had received other forms of treatment. Twenty-one per cent of the colonic-irrigation group had bloody diarrhea, as compared with 1 per cent of the non-irrigation group (P = 0.00013). Thirty-seven per cent of the colonic-irrigation group who submitted specimens had evidence of amebic infection on either stool examination or serum titer, as compared with 2.4 per cent in the non-irrigation group (P = 0.00012). Persons who were given colonic irrigation immediately after a person with bloody diarrhea received it were at the highest risk for the development of amebiasis. Tests of the colonic-irrigation machine after routine cleaning showed heavy contamination with fecal coliform bacteria. The severity of disease in this outbreak may have been related to the route of inoculation. 相似文献
26.
C T Healy L N Martin E D Roberts A S Rubin 《Laboratory investigation; a journal of technical methods and pathology》1989,60(3):462-470
A novel method which avoids the use of complete Freund's adjuvant (which can be arthritogenic) has been used to induce collagen II arthritis in both primates and mice. A solution of bovine type II collagen was dried onto nitrocellulose filters and implanted in the peritoneal cavity of experimental animals. Primate and mouse joints were scored by clinical as well as gross and microscopic parameters. The polyarthritis that developed in both rhesus monkeys (Macaca mulatta) and DBA/1 LAC J mice was characterized by synovial cell proliferation and endothelial cell hyperplasia, and by a perivascular mononuclear cell infiltrate of the synovium. Primates were analyzed further for anti-type II collagen antibody titers and delayed type hypersensitivity to type II collagen. Anti-type II collagen serum titers appeared to be unrelated to the disease pathology; the primates did not display delayed-type hypersensitivity to type II collagen. Control monkeys and mice implanted with collagen-free nitrocellulose filters were normal upon clinical and histopathological analysis. This protocol offers the advantage of the induction of arthritis due solely to immunization with antigen. 相似文献
27.
G B Doherty D S Moorthi P Namsirikul D Subramony L Healy K F MacDonnell 《Annals of allergy》1978,41(4):208-210
In 16 guinea pigs the pulmonary circulation was isolated from the pulmonary systemic circulation and perfused with Tris buffer or with Tris buffer containing cromolyn sodium. The lungs were first ventilated with 100% O2 and then 100% N2 to induce alveolar hypoxia. The effluent was collected from the aorta and assayed for histamine by the fluorometric method. In all seven animals perfused with Tris alone (no cromolyn) a marked elevation of the effluent histamine was demonstrated. In the group perfused with buffer containing cromolyn there was a substantial diminution in the response to hypoxia. Therefore, cromolyn sodium partially blocked hypoxia-mediated histamine release. 相似文献
28.
1. Measurements of stature and sitting height were made at 0930 and 1400 h on 19 boys aged 12-14 years with the "stretching upward" technique. 11 different boys were similarly measured at 1000 and 1700 h. 2. The average decrease in stature from 0930 to 1400 h was 2.0 mm and from 1000 to 1700 h was 4.6 mm. The corresponding values for sitting height were 2.0 mm and 2.8 mm. 3. No strong evidence for individual differences in diurnal change was found. 4. The standard error of stature measurement, estimated from duplicate measurements taken five minutes apart by the same observer in the afternoon sessions, was +/- 1.8 mm. 相似文献
29.
J. K. Healy P. A. Fraser J. A. Young 《Pflügers Archiv : European journal of physiology》1976,363(1):69-73
Summary The effect of angiotensin II on nett electrolyte transport by the main duct of the rabbit mandibular gland was investigated in vitro using a perfused duct preparation bathed in a Haemaccel®-nutrient salt solution. In a bath concentration of 4×10–10 M, angiotensin reduced nett absorption of Na+ and Cl– by about 8% and depolarized the transepithelial electrical potential difference (P.D.) by about 13%; the drug had no effect on ductal transport of K+ and HCO
3
–
. In both lower (4×10–11 M) and higher (4×10–9 M) concentrations, angiotensin had qualitatively similar effects. After exposure to the hormone for about 30 min, Na+ transport and P.D. became unstable and gradually fell away towards zero. It is concluded that angiotensin in physiological concentrations has a specific inhibitory effect on Na+ absorption by salivary duct cells which could arise either from a change in the Na+ pump rate or from a conductance change in the apical or basal membrane of the epithelial cell. 相似文献
30.