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81.
BACKGROUND AND OBJECTIVES Corticotrophin releasing factor (CRF) is present in the human placenta and fetal membranes. Placental CRF content and plasma CRF concentrations rise throughout gestation and fail rapidly after delivery. The regulation of CRF production from the placenta is poorly understood. The objective of this study was to use the antiprogestin, mifepristone, to determine whether progesterone has a regulatory effect on CRF production in the first trimester of pregnancy. PATIENTS Women undergoing first trimester (gestation 5-12 weeks) therapeutic abortion (by suction curettage with and without the synthetic PGE, analogue, gemeprost (16,16-dimethyl-trans- Δ2-PGE1 methyl ester) vaginally 2-4 hours prior to the procedure; or with 600 mg mifepristone 48 hours prior to receiving 1 mg gemeprost vaginally), second trimester therapeutic abortion (600 mg mifepristone, 1 mg gemeprost), In association with pre-term delivery (gestation 25-34 weeks) and at term (gestation 35-42 weeks) by spontaneous delivery, induced labour or elective Caesarean section. MEASUREMENTS immunohistochemical localization Of CRF and quantification of CRF content by radioimmunoassay of tissue extracts, in human placenta and fetal membranes. RESULTS CRF was Immunolocalized to the syncytlo-trophoblast cells of the placenta at ail stages of gestation from 5 to 42 weeks. In the fetal membranes CRF immunoreactlvity was localized in the epithelial and subepithelial cells of the amnion, some cells of the reticular and cellular layers of the chorion, and in decidual stroma. This pattern was seen in all tissues studied. Pretreatment with prostaglandins, mifepristone or both during the first trimester did not alter the distribution or the intensity of the CRF Immunostaining. Placental CRF content rose throughout gestation but, consistent with the Lmmunostaining results, was unaffected by the administration of mifepristone or by labour. CONCLUSIONS CRF is localized in the syncitlotropho-blast cells of the placenta and is clearly present early in the first trimester of pregnancy. The lack of an effect of mifepristone or mode of delivery suggests that syncytlo-trophoblast produces CRF constitutively throughout pregnancy. 相似文献
82.
Biostability and blood-contacting properties of sulfonate grafted polyurethane and Biomer. 总被引:1,自引:0,他引:1
H D Wabers T J McCoy A T Okkema R W Hergenrother M F Wolf S L Cooper 《Journal of biomaterials science. Polymer edition》1992,4(2):107-133
Sulfonate-containing polyurethanes were evaluated for in vivo biodegradation using subcutaneously implanted tensile bars. In addition, these anionically charged polyurethanes were evaluated for in vivo activation of human complement C3a and ex vivo platelet deposition in arteriovenously-shunted canines. The sulfonate derivatized polymers included laboratory synthesized polyurethane and Biomer. Other polymers used for references included Intramedic polyethylene, Silastic and a poly(ethylene oxide) based polyurethane. The biodegradation results indicated that Biomer and the laboratory sulfonated Biomer (both manufactured with stabilizers), remained mechanically stable, retaining both tensile strength and elasticity after 4 weeks of subcutaneous implantation. The unstabilized polyurethanes (with or without sulfonation), however, showed marked cracking and a loss of mechanical properties after the same period of subcutaneous implantation. Sulfonated polyurethanes depressed human complement C3a activation in plasma, as indicated by decreased levels of anaphylatoxin production. The results of canine ex vivo blood contacting experiments were conducted in both an acute and chronic model and demonstrated decreased platelet deposition and activation for the sulfonated polyurethanes. 相似文献
83.
Anticoagulant effects of sulphonated polyurethanes. 总被引:1,自引:0,他引:1
J H Silver A P Hart E C Williams S L Cooper S Charef D Labarre M Jozefowicz 《Biomaterials》1992,13(6):339-344
Sulphonated polyurethanes have been shown to have excellent blood contacting properties. In this paper, similar polyurethanes which are water soluble have been investigated to determine their influence on thrombus formation. These polymers were shown to delay clotting times in the following ways: by direct complex formation between the polymer and thrombin; by interference with fibrin polymerization; and by complex interactions between polymer, thrombin, plasma antiproteases and fibrinogen in plasma. 相似文献
84.
85.
Hepatitis C Viral (HCV) infection in the injection drug user (IDU) population is a major medical concern. Concurrent substance
abuse, co-morbid mental health conditions, poor socioeconomic status and a complex treatment protocol that is often incompatible
with the life styles of IDUs combine to account for poor uptake and completion of HCV treatment. This article discusses HCV
antiviral treatment issues relevant to IDUs chronically infected with this virus. The effect of non-injected substances of
abuse on treatment outcome is considered. Priority issues requiring research are discussed. 相似文献
86.
Zahava Sololmon Shimon E. Spiro Arik Shalev Avi Bleich Samuel Cooper 《Journal of traumatic stress》1992,5(2):217-223
Nine months after the residential stage of Koach, participants were asked to evaluate the program's effectiveness. Most of the veterans reported improvement in the areas queried, and especially in social relations, and nearly all of them stated that they would recommend the program to other veterans. The commander-therapists became the major source of help for these veterans following the Koach project, and about half reported that they participated regularly in self-help groups. Most of the participants acquired coping techniques that continued to serve them 9 months after the end of the residential stage of Koach. One of the more important measures of Koach was thought to be the veterans' own evaluations of the project, their assessment of the project's success in achieving its aims, and their satisfaction with it. In this article we will present the subjects' evaluations of treatment effectiveness as expressed in behavioral and emotional changes that they attributed to the treatment. 相似文献
87.
J. R. D. Matthews I. A. Cooper J. P. Matthews J. CHONG Ding 《Internal medicine journal》1992,22(2):123-128
In an attempt to improve response and survival rates in patients with non-Hodgkin's lymphoma, a relatively intense six drug regimen MATCOP was developed comprising four-weekly cycles of methotrexate (100mg/m2, IVY day 8), Adriamycin (30mg/m2, IVY days 1,2), teniposide (75 mg/rn2, IV, day 1), cyclophophamide (300 mg/m2, po, days one to five), Oncovin (1.4 mg/m2, IV: maximum 2 mg, days 8,15) and prednisolone (100 mg, po, days one to five). A randomised trial was conducted comparing MATCOP with the standard CHOP regimen, comprising three-weekly cycles of cyclophosphamide (750 mg/m2, IV, day 1), Adriamycin (50 mg/m2, IV, day 1), Oncovin (1.4 mg/m2 IV: maximum 2 mg, day 1) and prednisolone (100 mg, PO, days two to six). Eighty patients with large cell lymphoma, diffuse mixed small cleaved and large cell lymphoma or diffuse small cleaved cell lymphoma were randomised, 47 to MATCOP and 33 to CHOP. MATCOP patients experienced increased granulocytopenia, thrombocytopenia (p 0.0001), mucositis (p= 0.002) and infections (p= 0.01) compared to CHOP patients. Complete response rates were similar: 66% for MATCOP patients and 61% for CHOP patients. There were no apparent differences in the time to relapse for patients achieving CR, the time to treatment failure or the overall survival time. Thus despite an increase in toxicity, the more intense regimen MATCOP failed to confer any therapeutic benefit compared with the standard CHOP regimen. Survival was not influenced but toxicity was increased by dose intensification. (Aust NZ J Med 1992; 22: 123–128.) 相似文献
88.
89.
Characterization of a benzyladenine binding-site peptide isolated from a wheat cytokinin-binding protein: sequence analysis and identification of a single affinity-labeled histidine residue by mass spectrometry 总被引:3,自引:1,他引:2 下载免费PDF全文
A C Brinegar G Cooper A Stevens C R Hauer J Shabanowitz D F Hunt J E Fox 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(16):5927-5931
A wheat embryo cytokinin-binding protein was covalently modified with the radiolabeled photoaffinity ligand 2-azido-N6-[14C]benzyladenine. A single labeled peptide was obtained after proteolytic digestion and isolation by reversed-phase and anion-exchange HPLC. Sequencing by classical Edman degradation identified 11 of the 12 residues but failed to identify the labeled amino acid. Analysis by laser photodissociation Fourier-transform mass spectrometry of 10 pmol of the peptide independently confirmed the Edman data and also demonstrated that the histidine residue nearest the C terminus (underlined) was modified by the reagent in the sequence Ala-Phe-Leu-Gln-Pro-Ser-His-His-Asp-Ala-Asp-Glu. 相似文献
90.
V. M. Mann J. M. Cooper S. E. Daniel K. Srai P. Jenner C. D. Marsden A. H. V. Schapira 《Annals of neurology》1994,36(6):876-881
Elevated iron levels, enhanced oxidative damage, and complex I deficiency have been identified in the substantia nigra of Parkinson's disease patients. To understand the interrelationship of these abnormalities, we analyzed iron levels, ferritin levels, and complex I activity in the substantia nigra of patients with Parkinson's disease. Total iron levels were increased significantly, ferritin levels were unchanged, and complex I activities were decreased significantly in the substantia nigra samples. The failure of ferritin levels to increase with elevated iron concentrations suggests that the amount of reactive iron may increase in the substantia nigra of Parkinson's disease patients. There was no correlation between the iron levels and complex I activity or the iron-ferritin ratio and complex I activity in the substantia nigra samples. 相似文献