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31.
Lesley Barclay RN CM BA MEd Louise Everitt RN CM Post Grad Dip-Comm Health Frances Rogan RN CM B App S M Com Nurs Virginia Schmied RN CM BA MA Hons Aileen Wyllie RN CM BA MHPEd 《Journal of advanced nursing》1997,25(4):719-728
This paper presents the results of a qualitative study conducted by midwife researchers into women's experience of new motherhood. Data were collected using focus groups involving 55 first-time mothers and analysed using grounded theory method. The analysis produced six categories: 'realizing', 'unready', 'drained', 'aloneness', 'loss' and 'working it out'. The core category, 'becoming a mother', integrates all other categories and encapsulates the process of change experienced by women. Also explained are factors mediating the often distressing experience of becoming a mother. The analysis provides a conceptualization of early motherhood enabling the development of strategies for midwives, nurses and others helping women negotiate this challenge. 相似文献
32.
Summary— Experiments were designed to determine whether or not indapamide, an antihypertensive agent with vasodilator properties, inhibits endothelium-dependent contractions. Rings of aortae with and without endothelium from spontaneously hypertensive rats (SHR) were suspended in conventional organ chambers for the measurement of isometric force. Acetylcholine and adenosine diphosphate-β-S in the presence of a nitric oxide synthase inhibitor, caused endothelium-dependent contractions, which were inhibited by indapamide. The compound (10−4 M) also slightly reduced the contractions of rings without endothelium evoked by U-46,619, which activates thromboxane-endoperoxide receptors. These results demonstrate that indapamide inhibits endothelium-dependent contractions in the SHR aorta, and suggest that the inhibition is due, at least in part, to the action of the drug on the hypertensive vascular smooth muscle. 相似文献
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34.
Nichols KE Haines K Myung PS Newbrough S Myers E Jumaa H Shedlock DJ Shen H Koretzky GA 《Journal of leukocyte biology》2004,75(3):541-552
The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages. 相似文献
35.
Alan Ma Sunita Gurnasinghani Edwin P. Kirk Conor McClenaghan Gautam K. Singh Dorothy K. Grange Chetan Pandit Yung Zhu Tony Roscioli George Elakis Michael Buckley Bhavesh Mehta Philip Roberts Jonathan Mervis Andrew Biggin Colin G. Nichols 《American journal of medical genetics. Part A》2019,179(8):1585-1590
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS. 相似文献
36.
37.
Isolation of hybridoma cell lines and characterization of monoclonal antibodies against cholera enterotoxin and its subunits. 总被引:4,自引:5,他引:4 下载免费PDF全文
Hybridoma cell lines which produced monoclonal antibodies against cholera toxin were isolated. These cell lines were detected with an enzyme-linked immunosorbent assay screening procedure with purified cholera toxin or subunit A of cholera toxin. Seven cell lines were characterized with respect to their reactivity with cholera toxin subunits by Western blot analysis. Five clones produced antibodies which were directed against subunit A, and two clones produced antibodies which reacted with subunit B. These antibodies were also characterized by Western blot analysis for reactivity with the heat-labile enterotoxin produced by porcine and human enterotoxinogenic strains of Escherichia coli. Monoclonal antibodies which reacted with subunit A of cholera toxin also reacted with subunit A of both porcine and human heat-labile enterotoxins. In contrast, monoclonal antibodies to subunit B of cholera toxin did not react with subunit B of the heat-labile enterotoxin. Antibodies directed against subunit B neutralized the biological activity of cholera toxin in vitro in the S49 mouse lymphosarcoma assay. In contrast to polyclonal anti-subunit A antisera, monoclonal anti-subunit A from four of five clones had small but measurable neutralizing capacities in vitro. 相似文献
38.
Immunity to vaginal reinfection in female guinea pigs infected sexually with Chlamydia of guinea pig inclusion conjunctivitis. 总被引:3,自引:7,他引:3 下载免费PDF全文
Guinea pig boars were inoculated intraurethrally with the chlamydial agent of guinea pig inclusion conjunctivitis (GPIC). At the heights of their urethral infections, they were caged with sows in estrus. Whereas some of the sows had not been previously exposed to GPIC agent, others had received an intravaginal inoculation 5 to 8 weeks earlier. Those sows for which infected boars provided the first exposure were challenged by intravaginal inoculation 5 to 8 weeks later. Vaginal and conjunctival scrapings were taken regularly and stained for chlamydial inclusions. Titers of serum anti-GPIC antibodies and of vaginal secretory IgA anti-GPIC antibodies were determined by immunofluorescence. Our results show for the first time that a sexually acquired vaginal GPIC infection induces immunity to manual reinfection of the vagina. Because of the high incidence of secondary conjunctival infections among the vaginally infected sows, we could not provide a sound statistical basis for our tentative conclusion that manual infection of the vagina induces immunity to sexual reinfection. The results of our antibody titrations confirm previous work showing that vaginal GPIC infection induces formation of both serum antibody and vaginal secretory immunoglobulin A antibody. 相似文献
39.
Astrid LA. Kuijpers Rolph Pfundt Patrick LJM Zeeuwen Henri OF. Molhuizen Edwin CM. Mariman Peter CM. van de Kerkhof Joost Schalkwijk 《Clinical genetics》1998,54(1):96-101
Psoriasis is a multifactorial skin disease characterised by epidermal abnormalities and infiltration by lymphocytes and polymorphonuclear leukocytes (PMN). Skin-derived antileukoproteinase (SKALP), also known as elafin, is a potent inhibitor of human leukocyte elastase and proteinase 3, two PMN-derived proteinases implicated in tissue destruction and leukocyte migration. We have shown that, at least at the protein level, SKALP is significantly decreased in lesional skin of patients with pustular psoriasis compared with plaque-type psoriasis. This finding raised the possibility that SKALP could be one of the candidate genes for pustular forms of psoriasis. We therefore performed single strand conformation polymorphism (SSCP) analysis on the SKALP gene to screen for mutations/polymorphisms in the exons of 30 patients with plaque-type psoriasis, 15 patients with pustular psoriasis and 48 healthy controls. In exon 1 a polymorphism was detected at position + 43 relative to the translation start site, resulting in a substitution of threonine for alanine in the signal peptide. In the promoter region a dinucleotide repeat polymorphism was identified. Both polymorphisms were not associated with pustular psoriasis, or psoriasis in general. Our data indicate that the decrease in SKALP activity in pustular psoriasis is not caused by mutations in the coding region of the gene, and that there is no allelic association between pustular psoriasis and SKALP gene polymorphisms. 相似文献
40.
Narayan P. Verma Cynthia D. Nichols Manfred F. Greiffenstein Rajinder P. Singh Deborah Hurst-Gordon 《Brain topography》1989,1(3):183-191
Summary Thirty subjects (normal controls, patients with putative subcortical dementia and non-demented patient controls) were studied using advanced neurophysiological (16 scalp-electrode positions, computer-assisted brain electrical activity mapping, auditory oddball paradigm) and neuropsychological techniques. Our study suggests that waves earlier than P3 (N1, P2 and N2) are all correlated with global measures of cognitive functions. They are, however, differentially correlated with specific measures of cognitive functions, N1 and P2 with mental speed and N2 with short-term memory. The abnormalities of these waves (earlier than P3) may be an electrophysiologic marker of dementia in patients with putative subcortical states. 相似文献