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991.
PURPOSE: The present study explores p53 in relation to the following four aspects of node-negative breast carcinoma: epidemiologic risk factors, tumor histopathology, prognosis, and HER2/neu (HER) expression. MATERIALS AND METHODS: Immunohistochemical (IH) staining for p53 was performed on formaldehyde-fixed, paraffin-embedded primary invasive carcinomas from 440 node-negative patients with a median follow-up duration of 119 months. RESULTS: The IH expression, or lack thereof, of p53 separately or in combination with HER did not prove to be prognostically significant and there was no consistent association of p53 with epidemiologic risk factors. p53 was expressed in 68% of medullary carcinomas (MEDs), which is a significantly higher frequency (P < .001) than in lobular (9%) and duct (23%) carcinomas. p53 was not found in some types of low-grade carcinomas (tubular and papillary), and was observed in a minority of mucinous carcinomas. p53 was present significantly more often in carcinomas with high-grade or poorly differentiated nuclear grade than in low- or intermediate-grade tumors. There was an inverse statistically significant relationship between estrogen receptor (ER) positivity and p53 expression. Tumors with the p53(+)/HER(-) immunophenotype tended to be MEDs or duct carcinomas with a marked lymphoplasmacytic reaction. Infiltrating lobular carcinomas (IFLCs) were largely p53(-)/HER(-). p53(+)/HER(+) carcinomas had the best prognosis. The poorest outcome was associated with the p53(-)/HER(+) immunophenotype. This trend was statistically significant for recurrence-free and overall survival in patients with T1NOMO infiltrating duct carcinoma (IFDC). CONCLUSION: The IH demonstration of p53 was not a reliable prognostic indicator in the node-negative breast carcinoma patients studied and it was not associated with major epidemiologic risk factors. The combined immunophenotypic expression of p53 and HER was significantly associated with some histologic types of breast carcinoma and with prognosis in T1NOMO breast carcinoma.  相似文献   
992.
True histiocytic lymphoma (THL), as it is currently defined, is a rare entity. We report 12 cases of THL seen at Stanford over the last ten years. By definition, the neoplastic cells in each case showed histological and immunological evidence of histiocytic differentiation. Seven females and five males ranged in age from 9 to 67 years. Sites of involvement included lymph node, soft tissue, bone, stomach, small intestine, mediastinum, kidney, breast and salivary gland. Lymph nodes showed diffuse architectural effacement and/or a paracortical pattern of involvement. The infiltrates involved other tissues in a diffuse pattern. Cytologically the cells were characterized by abundant eosinophilic cytoplasm and enlarged, indented eccentrically placed nuclei containing prominent nucleoli. In all cases the cytological features were sufficiently atypical to indicate a neoplastic infiltrate. Paraffin section immunophenotyping demonstrated reactivity of the atypical cells for CD15, 43, 45RO, 45RB, 68, lysozyme and/or S100. In frozen sections, the atypical cells demonstrated reactivity for CD4 (cytoplasmic), 11c, 14, 15, and/or 68. Genotypic studies were performed on 3 cases, one of which showed rearrangements of immunoglobulin heavy and light chain genes. Follow-up was available on eleven patients, six of whom died of disease 0.5 to 36 months following diagnosis.  相似文献   
993.
BACKGROUND: This study attempted to determine the use of a single cycle of high dose cyclophosphamide (60 mg/kg/day x 2) with (N = 16) and without granulocyte macrophage colony stimulating factor (GM-CSF) (N = 12) followed by intensive treatment and autologous stem cell transplantation (ASCT) in patients with relapsed disease. METHODS: Ten patients with multiple myeloma, eight with non-Hodgkin's lymphoma, three with Hodgkin's disease, six with breast cancer, and one with ovarian cancer were studied. Eighteen patients were in resistant relapse (RR) and 10 had sensitive relapses (SRs). All patients had marrow involvement with tumor and had received extensive prior therapy. RESULTS: When responses were assessed just before undergoing ASCT, none of the patients achieved a complete response (CR). Overall, 17 of 28 patients (61%) achieved a partial response (PR). Seven of 18 patients with RR achieved PR (39%). All 10 patients with SR achieved a PR. There were three early deaths. Sixteen patients underwent peripheral blood stem cell (PBSC) collection. Ten of 16 patients received cyclophosphamide plus GM-CSF, and 6 received cyclophosphamide alone. In patients treated with cyclophosphamide plus GM-CSF and cyclophosphamide alone, a median of 5.52 x 10(6) CD34+ cells/kg (range, 0.26-30.49) and 5.72 x 10(6) (range, 1.25-15.66) were collected, respectively. There was no apparent improvement in collection efficiency with GM-CSF. Twenty-two of 28 patients proceeded to ASCT irrespective of response, a median of 45 days (range, 21-203 days) after cyclophosphamide administration. After transplantation, 11 achieved a CR (50%) and 6 a PR (27%). To date, eight patients are alive (median, 679 days; range, 215-1190 days) and five remain in CR more than 6 months (median, 321 days; range, 215-1190 days). All eight surviving patients achieved a PR after high dose cyclophosphamide. CONCLUSIONS: High dose cyclophosphamide reduced the tumor burden by at least 50% in all patients with sensitive disease and in 39% of patients with refractory disease. However, only 5 of 22 patients (23%) remained in CR after ASCT, and all had sensitive disease before the administration of cyclophosphamide. These data suggest that high dose cyclophosphamide followed by intensive treatment and ABMT does not improve the fraction of long term disease free survivors in patients with refractory disease. Future trials would probably be required to demonstrate the utility of intensive treatment in patients with responsive relapse.  相似文献   
994.
Dyspepsia is common in the general population, and despite a paucity of data, smoking, alcohol, and analgesics are believed to be important risk factors. The role of these environmental factors in subjects with uninvestigated dyspepsia was evaluated in a representative population sample. An age and gender stratified random sample of residents of Olmsted County, Minnesota, aged 20 to 64 years was mailed a valid self report questionnaire; 77% responded (n = 1644). Age and gender adjusted (1990 US white population) prevalence rates for dyspepsia (defined as frequent pain located in the upper abdomen, or nausea in the absence of a history of peptic ulcer disease) were calculated. Logistic regression analysis was used to estimate the association between dyspepsia and potential risk factors. The age and gender adjusted prevalence (per 100) of dyspepsia in the community was 21.8 (95% confidence interval 19.6, 23.9). Dyspepsia was significantly more common in younger subjects and females. Adjusting for age and gender, paracetamol (odds ratio (OR) = 2.2), aspirin (OR = 1.8), and smoking (OR = 1.5), but not alcohol (OR = 0.9), were associated with dyspepsia (all p < 0.05). When non-gastrointestinal somatic complaints were included in the logistic models, however, these environmental factors were no longer significant (OR = 1.3, 1.1, 1.2 and 0.9, respectively). Similar results were obtained when ulcer-like, dysmotility-like, and reflux-like dyspepsia were considered separately. The results were not significantly changed when subjects with a history of ulcer disease were included in the analyses. Smoking, alcohol, and analgesics may not therefore be important risk factors for dyspepsia in the community.  相似文献   
995.
The widespread use of standardized health surveys is predicated on the largely untested assumption that scales constructed from those surveys will satisfy minimum psychometric requirements across diverse population groups. Data from the Medical Outcomes Study (MOS) were used to evaluate data completeness and quality, test scaling assumptions, and estimate internal-consistency reliability for the eight scales constructed from the MOS SF-36 Health Survey. Analyses were conducted among 3,445 patients and were replicated across 24 subgroups differing in sociodemographic characteristics, diagnosis, and disease severity. For each scale, item-completion rates were high across all groups (88% to 95%), but tended to be somewhat lower among the elderly, those with less than a high school education, and those in poverty. On average, surveys were complete enough to compute scales scores for more than 96% of the sample. Across patient groups, all scales passed tests for item-internal consistency (97% passed) and item-discriminant validity (92% passed). Reliability coefficients ranged from a low of 0.65 to a high of 0.94 across scales (median = 0.85) and varied somewhat across patient subgroups. Floor effects were negligible except for the two role disability scales. Noteworthy ceiling effects were observed for both role disability scales and the social functioning scale. These findings support the use of the SF-36 survey across the diverse populations studied and identify population groups in which use of standardized health status measures may or may not be problematic.  相似文献   
996.
As American society becomes progressively violent, an ever-increasing number of gunshot wounds are being seen across the United States. Particularly challenging are injuries that involve the mandible and midface, not only because of problems with reconstructing bone and soft-tissue defects but also because of emergent problems with airway obstruction and neurovascular compromise. We present 40 cases of gunshot wounds to the mouth, mandible, and maxilla treated at Wake Forest University Medical Center during the past 7 years. The focus of this retrospective analysis is on emergency evaluation and treatment, complications encountered, and operative techniques used for reconstruction. Special emphasis is placed on recognizing and avoiding the complications of these injuries.  相似文献   
997.
Mutations of the N- and K-ras genes are the most frequent genetic aberrations in acute myeloid leukemia (AML) and their detection in preleukemic conditions such as the myelodysplastic syndrome (MDS) suggests a role in the earliest phases of leukemogenesis. Despite these observations, little is known about the clinical importance of ras mutations in AML. We studied the clinical impact of ras mutations in 99 patients with de novo AML. All patients were treated in two prospective multicenter trials. The polymerase chain reaction was used to amplify areas surrounding the codons 12, 13, and 61 of the three ras genes N-, K-, and H-ras from DNA from bone marrow cells, ras mutations were detected by an algorithm based on allele-specific oligonucleotide hybridization. Eighteen of 99 (18%) patients harbored mutations in either N- or K-ras. All of the observed mutations occurred in N-ras (N = 10) and K-ras (N = 5) or concurrently in both N- and K-ras (N = 3). There were no significant differences between ras-negative and ras-positive patients according to age, sex, blood counts, cytogenetic abnormalities, or French-American-British classification. However, univariate analysis suggested a longer survival in ras-positive patients (P = .11). When adjusted for age, which was the most important factor affecting outcome, the presence of a ras mutation emerged as a significant predictor for improved survival (P = .03) and along with lower bone marrow blast counts (P = .02) and better cytogenetic category (P = .01). However, the presence of an aberrant ras allele was strongly correlated with lower bone marrow blast counts (P = .007). Thus, whether a mutation in the N-ras or K-ras proto-oncogenes directly affects treatment outcome or indirectly through an association with lower leukemic burden remains to be determined. Nevertheless, these findings counter the prevailing bias that oncogene mutations lead to more aggressive behavior in human malignancies.  相似文献   
998.
The renin-angiotensin system is a major determinant of arterial pressure and volume homeostasis in mammals through the actions of angiotensin II, the proteolytic digestion product of angiotensinogen. Molecular genetic studies in several human populations have revealed genetic linkage between the angiotensinogen gene and both hypertension and increased plasma angiotensinogen. Transgenic mice were generated with a human angiotensinogen genomic clone to develop an animal model to examine tissue- and cell-specific expression of the gene and to determine if overexpression of angiotensinogen results in hypertension. Human angiotensinogen mRNA was expressed in transgenic mouse liver, kidney, heart, adrenal gland, ovary, brain, and white and brown adipose tissue and, in kidney, was exclusively localized to epithelial cells of the proximal convoluted tubules. Plasma levels of human angiotensinogen were approximately 150-fold higher in transgenic mice than that found normally in human plasma. The blood pressure of mice bearing the human angiotensinogen gene was normal but infusion of a single bolus dose of purified human renin resulted in a transient increase in blood pressure of approximately 30 mm Hg within 2 min. These results suggest that abnormalities in the angiotensinogen gene resulting in increased circulating levels of angiotensinogen could potentially contribute in part to the pathogenesis of essential hypertension.  相似文献   
999.
Genomic imprinting in mammals is believed to result from modifications to chromosomes during gametogenesis that inactivate the paternal or maternal allele. The genes encoding the insulin-like growth factor type 2 (Igf2) and its receptor (Igf2r) are reciprocally imprinted and expressed from the paternal and maternal genomes, respectively, in the fetal and adult mouse. We find that both genes are expressed in androgenetic, gynogenetic, and parthenogenetic preimplantation mouse embryos. These results indicate that inactivation of imprinted genes occurs postfertilization (most likely postimplantation) and that genomic imprinting and gene inactivation are separate processes. We propose that imprinting marks the chromosome so that regulatory factors expressed in cells at later times can recognize the imprint and selectively inactivate the maternal or paternal allele. For these genes, this finding invalidates models of genomic imprinting that require them to be inactive from the time of fertilization.  相似文献   
1000.
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