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51.
Although fathers perpetrate a significant proportion of child maltreatment, the intervention needs of abusive and neglectful fathers have not been adequately addressed or researched. This paper argues that well-designed treatment has the potential to benefit men, their children, and their families. However, the treatment needs of maltreating and at-risk fathers are unique, and programs must be designed accordingly. Based on the integration of parenting, child abuse, change promotion, and batterer treatment literatures, five principles to guide intervention with maltreating fathers are advanced: (a) overly controlling behavior, a sense of entitlement, and self-centered attitudes are primary problems of abusive fathers; thus, the development of child-management skills should not be an initial focus of intervention; (b) abusive fathers are seldom initially ready to make changes in their parenting; (c) fathers' adherence to gender-role stereotypes also contributes to their maltreatment of children; (d) the relationship between abusive fathers and the mothers of their children requires special attention; and (e) because abusive fathers have eroded children's emotional security, the need to rebuild trust will affect the pace of change and potential impact of relapse on the child. These principles are contrasted with the supportive and child-management goals of conventional group parenting programs, and the implications for providing service to fathers are considered.  相似文献   
52.
Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature.  相似文献   
53.
Monoclonal antibody production (mAb) first requires the availability of large amounts of pure immunogen for animal immunisation and fusion screening procedures. To overcome this obstacle, we have developed a simple method for rapid generation of pure antigen by generation of recombinant protein containing the antigen of interest fused to the hinge and Fc domains of human immunoglobulin (Ig). The Fc domain forms a convenient 'tag' to enable detection of the protein in supernatant of transfected cells and for purification of immunogen by protein A affinity chromatography. The only requirement for immunogen preparation using this methodology is that a DNA sequence encoding a portion of the molecule of interest is known and that a suitable PCR template is available. Antibody production can be tailored to specific protein domains, for example functional domains, by expressing solely those domains in the fusion protein. We illustrate the technique with two different fusions used to raise antibodies against the porcine and human analogues of a complement (C) regulatory protein, decay accelerating factor (DAF) (CD55). Use of the specific Ig-fusion protein and a control protein facilitated screening of fusions by ELISA. We demonstrate two expression systems used to generate Ig fusion proteins, the first utilised a commercial vector to incorporate an amino terminal leader sequence and carboxy terminal Ig domains. Low levels of expression required subcloning into a high expression vector and resulted in yields of fusion protein at between 2 and 10 mg per litre of supernatant. The second expression system utilised the high expression vector directly, Ig domains of the chosen immunoglobulin isotype were amplified from peripheral blood mononuclear cell (PBMC) RNA and ligated into the vector in frame with DNA encoding the antigen. We describe potential pitfalls that may be encountered while using Ig fusion proteins as immunogen and demonstrate ways in which to tailor their design for optimal mAb production.  相似文献   
54.
The gene WT1 is required for the normal development and function of the urogenital tract. Constitutional mutations are associated with familial Wilms tumor and syndromes such as Denys-Drash syndrome (DDS) characterized by nephropathy, genital anomalies and often a predisposition to Wilms tumor. We report a case of constitutional WT1 mutation in an XX female with multifocal Wilms tumor but no genital anomalies or renal dysfunction and, for the first time, review patients previously reported with this germline mutation. The mutation (1084C>T) changes the amino acid arginine at position 362 to the translation stop codon TGA (R362X) resulting in a predicted truncated protein lacking three of the four zinc finger domains necessary for correct functioning of the gene. This constitutional mutation has been reported to cause a variety of phenotypes in eleven different patients, including the classical Denys-Drash phenotype of diffuse mesangial sclerosis which leads to early renal failure, genital anomalies in XY individuals and Wilms tumors. The absence of mesangial sclerosis and renal failure in our patient excludes DDS. Our case differs from those previously described as the normal kidney tissue shows some small subcapsular glomeruli indicating that the WT1 mutation has impaired nephron development. This patient extends the range and variation of phenotypes that may arise from a specific germline mutation in WT1.  相似文献   
55.
Expression of luminal and basal cytokeratins in human breast carcinoma   总被引:32,自引:0,他引:32  
We have examined basal and luminal cell cytokeratin expression in 1944 cases of invasive breast carcinoma, using tissue microarray (TMA) technology, to determine the frequency of expression of each cytokeratin subtype, their relationships and prognostic relevance, if any. Expression was determined by immunocytochemistry staining using antibodies to the luminal cytokeratins (CKs) 7/8, 18 and 19 and the basal markers CK 5/6 and CK 14. Additionally, assessment of alpha-smooth muscle actin (SMA) and oestrogen receptor status (ER) was performed. The vast majority of the cases showed positivity for CK 7/8, 18 and 19 indicating a differentiated glandular phenotype, a finding associated with good prognosis, ER positivity and older patient age. In contrast, basal marker expression was significantly related to poor prognosis, ER negativity and younger patient age. Multivariate analysis showed that CK 5/6 was an independent indicator for relapse free interval. We were able to subgroup the cases into four distinct phenotype categories (pure luminal, mixed luminal/basal, pure basal and null), which had significant differences in relation to the biological features and the clinical course of the disease. Tumours classified as expressing a basal phenotype (the combined luminal plus basal and the pure basal) were in a poor prognostic subgroup, typically ER negative in most cases. These findings provide further evidence that breast cancer has distinct differentiation subclasses that have both biological and clinical relevance.  相似文献   
56.
BACKGROUND: The introduction of the Quality and Outcomes Framework (QOF) provides a quantitative way of assessing quality of care in general practice. We explore the achievements of general practice in the first year of the QOF, with specific reference to practice funding and contract status. AIM: To determine the extent to which differences in funding and contract status affect quality in primary care. DESIGN OF STUDY: Cross-sectional observational study using practice data obtained under the Freedom of Information Act 2000. SETTING: One hundred and sixty-four practices from six primary care trusts (PCTs) in England. METHOD: Practice data for all 164 practices were collated for income and contract status. The outcome measure was QOF score for the year 2004-2005. All data were analysed statistically. RESULTS: Contract status has an impact on practice funding, with Employed Medical Services (EMS) and Personal Medical Services (PMS) practices receiving higher levels of funding than General Medical Services (GMS) practices (P<0.001). QOF scores also vary according to contract status. Higher funding levels in EMS practices are associated with lower QOF scores (P=0.04); while GMS practices exhibited the opposite trend, with higher-funded practices achieving better quality scores (P<0.001). CONCLUSION: GMS practices are the most efficient contract status, achieving high quality scores for an average of pound 62.51 per patient per year. By contrast, EMS practices are underperforming, achieving low quality scores for an average of pound 105.37 per patient per year. Funding and contract status are therefore important factors in determining achievement in the QOF.  相似文献   
57.
58.
Cell lines derived from tumors contain numerous chromosomal aberrations and are the focus of study in tumor evolution. The ovarian teratocarcinoma cell line PA-1 demonstrates a single chromosomal aberration: a reciprocal t(15;20)(p11.2;q11.2). A complete molecular genetic analysis was undertaken to characterize this cell line. The PA-1 cell line was studied with fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), bacterial artificial chromosome (BAC) microarray, and Western blotting. Amplification of 20q is frequently implicated in both breast and ovarian cancer; this region contains a number of oncogenes including MDM2, ZNF217, and the ovarian tumor marker WFDC2 (alias HE4). FISH revealed gene amplification of AIB1 (now known as NCOA3) but not STK15 (now known as AURKA). Immunoblot analysis demonstrated 3.6-fold overexpression of the AIB1 protein product, but no elevation of the STK15. BAC cancer gene microarray analysis showed gene amplification of > or =1.20 for five oncogenes. The presence of a consistent single change in PA-1, the t(15;20)(p11.2;q11.2), suggests that the aberration is significant with respect to the transformation status of the cell line. This translocation appears to cause overexpression of AIB1 (and perhaps other proteins), which may provide an immortalizing effect on this cell line.  相似文献   
59.
Malignant melanoma of soft parts (MMSP) was originally described as a distinct entity by Enzinger in 1965 and was termed “clear cell sarcoma of tendons and aponeuroses” because of its association with tenosynovial structures. It has been shown immunophenotypically and ultrastructurally that this tumor is derived from neuroectoderm and shares a number of features with cutaneous melanoma. Over 95% of MMSPs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of MMSP of the head and neck region involving the posterior cervical region in a 15-year-old Hispanic male and reviews the literature on MMSP. Ultrastructural examination showed rudimentary cell attachments, smooth cell membranes, discontinuous basal lamina, scanty glycogen, and occasional premelanosomes in some tumor cells. Cytogenetic analysis showed a reciprocal translocation between the long arms of chromosomes 12 and 22 [t(12:22)(q13;q12.2)], characteristic for MMSP and not seen in cutaneous melanoma. Survival in MMSP has been correlated with tumor size, tumor necrosis, and ploidy status. Overall reported clinical outcome for this tumor is as follows: died of disease, 45%; alive with disease, 23%; no evidence of disease, 30%; and died of other causes, 2%. MMSP represents a distinct entity with a characteristic ultrastructural appearance and a tumor defining cytogenetic translocation.  相似文献   
60.
The role of the soluble pool (cytoplasmic or cytosolic) of [3H]-aldosterone binding sites in the toad bladder was assessed by the use of two spirolactones, prorenone and spironolactone as a reference drug. Prorenone fulfills all the criteria for a specific competitive antagonist of aldosterone for its effect on Na+ transport. Compared with spironolactone (Ki approximately equal to 1 microM), prorenone was about eightfold less potent (Ki approximately equal to 8 microM). Competition for [3H]aldosterone binding sites by spironolactone and prorenone revealed an order of potency (spironolactone greater than prorenone) that corresponded to their antagonist activities in the Na+ transport assay. There was a linear correlation between the effects of the two spirolactones on the aldosterone-stimulated Na+ transport and their ability to displace [3H]aldosterone from its binding sites in the soluble pool. Finally [3H]prorenone binding sites were detected in the soluble pool but an insignificant number of antagonist-receptor complexes were found associated with the nuclear pool. Our study indicates that the aldosterone binding sites of the soluble pool are indeed mineralocorticoid receptors, which are probably the first intracellular mediators leading to an increased Na+ reabsorption.  相似文献   
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