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141.
142.
 To assess the prognostic significance of silver-stained nucleolar organizer region (AgNOR) proteins, a standardized AgNOR analysis was performed on 78 patients affected by early (EGC, n=24) or advanced (AGC, n=54) gastric carcinomas. The histopathological diagnosis, grading and staging were done according to WHO and UICC recommendations; the mean follow-up time was 56.9 months. Visualization and quantification of AgNORs were made in formalin-fixed, paraffin-embedded sections as specified in the guidelines of the Committee on AgNOR Quantification (1995). Statistical analysis was performed on the mean AgNOR area values (NORA). Highly significant differences (P<0.001) were found in NORA values between EGC and AGC, between low- and high-grade gastric carcinomas and between patients dead from gastric cancer and living patients. In addition, significant P values were found on comparison of NORA values relating to pT status, pN status and stage. Comparison of Kaplan-Meier survival curves revealed that patients affected by gastric carcinomas with higher NORA values (>5.213 μm2) had a worse prognosis. Finally, using Cox multiple regression analysis, the AgNOR quantity emerged as a useful independent prognostic variable to predict the final outcome of patients affected by EGC or AGC. Received: 26 September 1997 / Accepted: 26 January 1998  相似文献   
143.
The biodegradability of solution-cast films of poly(D (–)-3-hydroxybutyrate) (PHB) blended with the melt-compatible component atactic poly(epichlorohydrin) (aPECH) was investigated. A bacterium which produced extracellular enzymes that degraded PHB even when blended with aPECH was isolated, and tentatively designated as Aureobacterium saperdae. The growth rate of A. saperdae decreased with increasing aPECH content in the blend, up to films containing 60 wt.-% aPECH, at which composition growth was completely inhibited. The decrease in the bacterial growth rate could be due to the dilution of PHB molecules on the blend film surface caused by the presence of aPECH molecules. At the stationary phase of bacterial growth the percentage of weight loss of blend films decreased with increasing aPECH fraction, which was probably due to the lower accessibility of PHB when blended with aPECH. During the bacterial growth only PHB was metabolized, whereas neither degradation nor abiotic release of aPECH was detected for blend films.  相似文献   
144.
Myxoid leiomyosarcoma of the ovary: Analysis of three cases   总被引:2,自引:0,他引:2  
The first three cases of myxoid leiomyosarcoma occurring in the ovary are reported. Two cases in stage III were found in postmenopausal patients and a further case was found in stage I in a 32-year-old. All masses were large and gelatinous with cystic change, necrosis, and hemorrhage, but both uteri and ligaments and contralateral adnexa appeared normal. Microscopically, the tumors showed a predominantly reticular meshwork of elongated cells surrounded by abundant basophilic material. While electron microscopy proved inconclusive due to nondifferentiation, the use of monoclonal antibodies against smooth muscle actin demonstrated a smooth muscle type of differentiation. The differential diagnosis of this rare ovarian condition includes other myxoid ovarian lesions, such as ovarian edema, myxoma, endodermal sinus tumors, and the sarcomatous component of malignant mixed müllerian tumor and carcinosarcoma, as well as lymphovascular tumors. Since mitotic count due to decreased cellular density is unusually low in myxoid leiomyosarcoma, capsular rupture and clinical stage seem to be more reliable prognostic markers. The highly aggressive behavior of myxoid leiomyosarcoma parallels that of typical ovarian leiomyosarcoma. Two of the three patients in this series died of tumor at 13 and 24 months after diagnosis; the other patient is free of disease at 3 years after diagnosis.  相似文献   
145.
Summary: An intrinsic (oncogene-driven) pathway and an extrinsic (microenvironment-driven) pathway connect inflammatory reactions and cancer. M2-polarized tumor-associated macrophages and the related myeloid-derived suppressor cells are key prototypic components of smoldering inflammation driving neoplastic progression. However, mononuclear phagocytes can exert anti-tumor activity by killing tumor cells and eliciting tissue disruptive reactions (M1), a likely scenario in the early phases of carcinogenesis of immunogenic tumors and following therapeutic intervention. Shifting the macrophage balance represents a viable therapeutic target. Herein, the 'macrophage balance' is discussed in the context of the apparent paradox of tumor promotion by innate immunity-driven inflammation and the seemingly opposed tumor surveillance by adaptive immune responses.  相似文献   
146.
The karyotype of a mouse trapped in a hybrid zone between a Robertsonian (Rb) population (2n=22) and a population with the standard karyotype (2n=40-all-telocentrics) shows two Rb chromosomes with new arm compositions. We suggest that whole-arm reciprocal translocations between Rb chromosomes gave rise to the new chromosome constitution and that such events can greatly help in understanding house mouse karyotype diversification and chromosomal speciation.  相似文献   
147.
Normal human neutrophils were found to destroy ox red blood-cell targets when incubated on micropore filters coated with aggregated IgG, as determined by the51Cr release method. An intact neutrophil oxidative metabolism was essential for the cytotoxic event, since cells from patients with chronic granulomatous disease failed to exert any cytolysis. The target-cell destruction was prevented by catalase, azide, and cyanide and was enhanced by superoxide dismutase, suggesting involvement of the myeloperoxidase-hydrogen peroxide system. Neutrophil-mediated cytotoxicity was markedly amplified by the chemotactic peptideN-formyl-methionyl-leucylphenylalanine, as a result of an increased activity of the myeloperoxidase-hydrogen peroxide cytolytic system itself. This system of cytotoxicity provides a direct evidence for the neutrophil capacity of destroying bystander target cells under conditions simulating thein vivo immunologically mediated tissue injury and offers an excellent model to study events occurring during immune complex diseases.Supported by Grant 83.00902.96/115.11547 from the Italian CNR-PFCCN.  相似文献   
148.
C-reactive protein is one of the most widely used indicators of the response of acute-phase proteins. The measurement of C-reactive protein in dengue, however, is clinically not useful, because of marginally elevated levels and absent association with disease severity. The prototypic long pentraxin, pentraxin 3, is an acute phase protein that is structurally related but distinct from C-reactive protein which has proven to correlate with the severity of bacterial infection in critically ill patients. The potential involvement of pentraxin 3 in dengue and its aptitude to predict more severe disease or poor clinical outcome has not been studied previously. We therefore measured pentraxin 3 plasma levels in 44 dengue virus infected patients. Pentraxin 3 levels were strikingly higher when compared to C-reactive protein levels, with highest pentraxin 3 values observed in the first 7 days after the onset of symptoms. Median pentraxin 3 levels at admission and peak levels during follow up were higher in patients suffering from dengue shock syndrome (at admission: 119.3 ng/ml [interquartile range 61.8--188.7], peak values during follow up: 147.9 ng/ml [interquartile range 85.7--204.3]) compared to levels found in patients with dengue fever and dengue hemorrhagic fever (at admission: 59.0 ng/ml [interquartile range 28.6--100.3], P=0.040; peak values during follow up: 80.8 ng/ml [interquartile range 36.1--168.1], P=0.020). Our results indicate that pentraxin 3 seems to be a marker of infection better than C-reactive protein in dengue. The role of pentraxin 3 in the pathogenesis of dengue and its potential as an early prognostic indicator of disease severity needs further assessment.  相似文献   
149.
Mitochondrial impairment has been implicated in the pathogenesis of the amyotrophic lateral sclerosis (ALS). Furthermore, mitochondrial-specific polymorphisms were previously related to other neurodegenerative diseases, such as Parkinson, Friedreich and Alzheimer disease. To investigate if specific genetic polymorphisms within the mitochondrial genome (mtDNA) could act as susceptibility factors and contribute to the clinical expression of sporadic ALS (sALS), we have genotyped predefined European mtDNA haplogroups in 222 Italian patients with sALS and 151 matched controls. Individuals classified as haplogroup I demonstrated a significant decrease in risk of ALS versus individuals carrying the most common haplogroup, H (odds ratio 0.08, 95% confidence interval 0.04-0.4, p < 0.01). Further stratification of the dataset by sex, age and site of onset of disease and survival failed to reach significance for association. Our study provides evidence of the contribution of mitochondrial variation to the risk of ALS development in Caucasians. Further it may help elucidate the mechanism of the mitochondrial dysfunction detectable in ALS, and may be of relevance in development of strategies for the treatment of this disease.  相似文献   
150.
BACKGROUND: Subjective quality of life has gained a crucial role as a global measure of outcome in mental health care. This study aimed to investigate the impact of meeting needs for care, as assessed by both patients and mental health professionals, to improve the subjective quality of life in a sample of patients receiving community-based psychiatric care. METHOD: The study was conducted using a 4-year prospective longitudinal design. A cohort of patients from the South-Verona Community-based Mental Health Service (CMHS) was assessed at baseline and follow-up using, among other social and clinical measures, the Camberwell Assessment of Need (both staff and patient versions) and the Lancashire Quality of Life Profile. Predictors of changes of subjective quality of life were explored using block-stratified multiple regression procedures. RESULTS: Improvement in patients' clinical conditions as well as the reduction in patient-rated unmet needs in the social domain predicted an increase in subjective quality of life over 4 years; changes in staff-rated needs did not show any association with changes in subjective quality of life. CONCLUSIONS: Meeting self-perceived social needs, beyond symptoms reduction, seems to be of particular importance for ensuring a better quality of life for people with mental disorders. If the main goal of mental health care is to improve the quality of life of users, a policy of actively addressing patient-rated needs should be implemented.  相似文献   
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