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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.
G P Kent J R Greenspan J L Herndon L M Mofenson J A Harris T R Eng H A Waskin 《American journal of public health》1988,78(2):139-143
In the period November 1, 1985 to January 31, 1986, 703 cases of giardiasis were reported in Pittsfield, Massachusetts (population 50,265). The community obtained its water from two main reservoirs (A and B) and an auxiliary reservoir (C). Potable water was chlorinated but not filtered. The incidence of illness peaked approximately two weeks after the city began obtaining a major portion of its water from reservoir C, which had not been used for three years. The attack rate of giardiasis for residents of areas supplied by reservoir C was 14.3/1000, compared with 7.0/1000 in areas that received no water from reservoir C. A case-control study showed that persons with giardiasis were more likely to be older and to have drunk more municipal water than household controls. A community telephone survey indicated that over 3,800 people could have had diarrhea that might have been caused by Giardia, and 95 per cent of households were either using alternate sources of drinking water or boiling municipal water. Environmental studies identified Giardia cysts in the water of reservoir C. Cysts were also detected in the two other reservoirs supplying the city, but at lower concentrations. This investigation highlights the risk of giardiasis associated with unfiltered surface water systems. 相似文献
33.
Preeti G. Lal Roopa S. Ghirnikar Lawrence F. Eng 《Journal of molecular neuroscience : MN》1996,29(1):93-104
Glial fibrillary acidic protein (GFAP) is the principal intermediate filament protein found in mature astrocytes. Although
the exact function of GFAP is poorly understood, it is presumed to stabilize the astrocyte’s cytoskeleton and help in maintaining
cell shape. Previous studies from our laboratory have shown that when astrocytes were cocultured with primary Schwann cells
(pSCs), astrocytes became hypertrophied and fibrous with intensely positive GFAP staining and segregated Schwann cells (SCs)
into pockets. In order to understand the functional role of GFAP in this already established astrocyte-SC coculture model,
we generated GFAP-negative cell lines from a GFAP-positive astrocytoma cell line and cocultured both the cell lines with pSCs.
Our studies demonstrate that the GFAP-positive cell line put out processes toward the SCs, whereas the GFAP-negative cells
did not form processes and the majority of the cells remained round. The most significant and interesting finding of this
study, however, is the formation of elaborate processes by SCs when grown in coculture with the astrocytoma cells, unlike
SCs cultured alone, which showed their typical bipolar spindle-shaped morphology. The extent of processes did not seem to
be dependent on GFAP, since SCs cultured with both the cell lines formed similar processes. This coculture model may be useful
in elucidating the factor(s) responsible for the formation of processes by SCs and can be further help in our understanding
of the mechanism of morphological transformation of SCs. 相似文献
34.
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
35.
C. R. Thambi Dorai V. Muthu Alhagi Ng Chee Eng Z. Ismail A. Yakub 《Pediatric surgery international》1998,14(1-2):84-85
A neonate with severe respiratory distress due to a benign mediastinal teratoma (MT) is reported. Despite early and easy
surgical excision of the tumor, the child died due to poor cardiac function. Only ten cases of MT in neonates have been reported
in the literature so far. While the tumor has been known to interfere with lung development in utero, postnatal myocardial
dysfunction due to poor heart development has not been previously documented.
Accepted: 22 September 1997 相似文献
36.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
37.
Non-Type b Haemophilus influenzae Infections in Adults with Reference to Biotype 总被引:2,自引:4,他引:2
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Robert H. K. Eng Michael L. Corrado Dennis Cleri Marcelino F. Sierra 《Journal of clinical microbiology》1980,11(6):669-671
We report three cases of serious non-group b Haemophilus influenzae infections. The significance of these isolates with respect to both biotypes and serotypes is discussed. 相似文献
38.
39.
PTEN mutational spectra,expression levels,and subcellular localization in microsatellite stable and unstable colorectal cancers 总被引:9,自引:0,他引:9
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Zhou XP Loukola A Salovaara R Nystrom-Lahti M Peltomäki P de la Chapelle A Aaltonen LA Eng C 《The American journal of pathology》2002,161(2):439-447
PTEN on 10q23.3 encodes a dual-specificity phosphatase that negatively regulates the phosphoinositol-3-kinase/Akt pathway and mediates cell-cycle arrest and apoptosis. Germline PTEN mutations cause Cowden syndrome and a range of several different hamartoma-tumor syndromes. Hereditary nonpolyposis colon cancer (HNPCC) syndrome is characterized by germline mutations in the mismatch repair (MMR) genes and by microsatellite instability (MSI) in component tumors. Although both colorectal carcinoma and endometrial carcinoma are the most frequent component cancers in HNPCC, only endometrial cancer has been shown to be a minor component of Cowden syndrome. We have demonstrated that somatic inactivation of PTEN is involved in both sporadic endometrial cancers and HNPCC-related endometrial cancers but with different mutational spectra and different relationships to MSI. In the current study, we sought to determine the relationship of PTEN mutation, 10q23 loss of heterozygosity, PTEN expression, and MSI status in colorectal cancers (CRCs). Among 11 HNPCC CRCs, 32 MSI+ sporadic cancers, and 39 MSI- tumors, loss of heterozygosity at 10q23.3 was found in 0%, 8%, and 19%, respectively. Somatic mutations were found in 18% (2 of 11) of the HNPCC CRCs and 13% (4 of 32) of the MSI+ sporadic tumors, but not in MSI- cancers (P = 0.015). All somatic mutations occurred in the two 6(A) coding mononucleotide tracts in PTEN, suggestive of the etiological role of the deficient MMR. Immunohistochemical analysis revealed 31% (14 of 45) of the HNPCC CRCs and 41% (9 of 22) of the MSI+ sporadic tumors with absent or depressed PTEN expression. Approximately 17% (4 of 23) of the MSI- CRCs had decreased PTEN expression, and no MSI- tumor had complete loss of PTEN expression. Among the five HNPCC or MSI+ sporadic CRCs carrying frameshift somatic mutations with immunohistochemistry data, three had lost all PTEN expression, one showed weak PTEN expression levels, and one had mixed tumor cell populations with weak and moderate expression levels. These results suggest that PTEN frameshift mutations in HNPCC and sporadic MSI+ tumors are a consequence of mismatch repair deficiency. Further, hemizygous deletions in MSI- CRCs lead to loss or reduction of PTEN protein levels and contribute to tumor progression. Finally, our data also suggest that epigenetic inactivation of PTEN, including differential subcellular compartmentalization, occurs in CRCs. 相似文献
40.