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151.
OBJECTIVE: To investigate the diagnostic value of p53 protein and DNA analysis in the study of serous effusions. STUDY DESIGN: A total of 76 samples of serous effusions were studied by immunohistochemistry for p53 protein and flow cytometric (FCM) DNA analysis. The results were correlated with final cytologic diagnoses, which were confirmed by immunohistochemistry using antibodies against cytokeratin, carcinoembryonic antigen, epithelial membrane antigen and fibronectin. RESULTS: Final cytologic diagnoses included 28 malignant effusions and 48 benign effusions. No expression of p53 protein was seen in benign effusions. In contrast, p53 protein expression was seen in 19/28 (sensitivity 68%) malignant effusions. FCM detected aneuploid cells in 12/28 (43% sensitivity) of malignant and 0/46 of benign effusions. Immunohistochemical determination of p53 protein combined with FCM DNA analysis increased sensitivity to 79%. CONCLUSION: Immunohistochemical determination of p53 protein and FCM DNA analysis can aid in making an accurate and specific diagnosis of serous effusions, but the principal limitation of these tests is their relatively low sensitivity.  相似文献   
152.
Utilizing site-directed mutagenesis, 77 charged and polar residues that are highly exposed on the surface of human thrombin were systematically substituted with alanine. Functional assays using thrombin mutants identified residues that were required for the recognition and cleavage of the procoagulant substrate fibrinogen (Lys21, Trp50, Lys52, Asn53 + Thr55, Lys65, His66, Arg68, Tyr71, Arg73, Lys77, Lys106 + Lys107, Asp193 + Lys196, Glu202, Glu229, Arg233, Asp234) and the anticoagulant substrate protein C (Lys21, Trp50, Lys65, His66, Arg68, Tyr71, Arg73, Lys77, Lys106 + Lys107, Glu229, Arg233), interactions with the cofactor thrombomodulin (Gln24, Arg70) and inhibition by the thrombin aptamer, an oligonucleotide-based thrombin inhibitor (Lys65, His66, Arg70, Tyr71, Arg73). Although there is considerable overlap between the functional epitopes, distinct and specific residues with unique functions were identified. When the functional residues were mapped on the surface of thrombin, they were located on a single hemisphere of thrombin that included both the active site cleft and the highly basic exosite 1. No functional residues were located on the opposite face of thrombin. Residues with procoagulant or anticoagulant functions were not spatially separated but interdigitated with residues of opposite or shared function. Thus thrombin utilizes the same general surface for substrate recognition regardless of substrate function although the critical contact residues may vary.  相似文献   
153.
OBJECTIVES: Transitional cell carcinomas of upper urinary tract (uttTCC) constitute 5% to 6% of all urothelial tumors. Ureteropyeloscopy has become the standard for clinical evaluation of uutTCC. Moreover, endoscopic treatments have been advocated as a conservative approach for low grade tumors or patients with intermediate grade tumors whose renal function is compromised. Therefore, grading has become the most predictive variable in defining therapeutic approach. In addition to morphologic evaluation, a series of biologic markers may be used to increase the accuracy of grading such as DNA analysis and p53 protein expression. In this study, we have evaluated these markers by means of cell image analysis with the SAMBA 400 system. METHODS: Thirteen cases of uttTCC were studied with cytologic smear, cell block, and histologic confirmation. DNA analysis was performed on cytologic smear. Immunostaining was performed on cell blocks. A grade was assigned on the basis of DNA evaluation and p53 expression quantitation. These grades were combined for each case and compared with the initial cytologic grading and the final histologic grading. RESULTS: Cytology alone diagnosed TCC in all but 1 case that was diagnosed atypical. Discrepancies were found in primary grading: cytologic grading concurred with histologic grading in 6 of the 13 cases. CONCLUSIONS: These results, although in a limited but selected number of cases, show the potential of computerized evaluation of biologic markers as parameters for a more objective grading of tumors.  相似文献   
154.
A 22-year-old Chinese man, a HBsAg carrier, presented with relapse of thyrotoxic Graves' disease complicated by thrombocytopenia and hepatitis. Platelet count and liver enzymes gradually improved following successful treatment of the thyrotoxicosis with radioactive iodine. Possible pathogenetic links and therapeutic implications are discussed.  相似文献   
155.
Our goals were to determine the prognostic value of a yolk sac or fetal heart motion seen during an early accurately dated transvaginal ultrasound (TVU). We reviewed 225 consecutive pregnancies for fetal heart motion data. Furthermore, 63 pregnancies following in-vitro fertilization were reviewed for yolk sac information. The TVU was performed between 5 and 6 weeks following presumed conception (heart motion data) and between 22 and 32 days following in-vitro fertilization (yolk sac data). Pregnancies were followed until an ongoing pregnancy or spontaneous abortion was documented. The presence of a yolk sac between 22 and 32 days from fertilization was associated with the development of fetal heart motion in 94% of cases. The absence of the yolk sac by 32 days after fertilization was always associated with a poor outcome. In women < 36 years of age, the presence of fetal heart motion was associated with a spontaneous abortion in only 4.5% of the cases. However, the incidence of spontaneous abortion following fetal heart motion increased to 10% in women 36-39 years and 29% in women > or = 40 years of age. The presence of heart motion should not be considered a reassuring sign in the older woman. These data have implications regarding early embryology and the counselling of infertility patients.  相似文献   
156.
Eighteen canine microsatellites   总被引:1,自引:0,他引:1  
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157.
BACKGROUND/AIMS: Primary carcinoma of the gallbladder is rare and associated with a late diagnosis and poor prognosis. Concurrent acute cholecystitis frequently obscures the presence of carcinoma. The information regarding gallbladder carcinoma with acute cholecystitis is limited. In order to better understand the presentation of gallbladder carcinoma with acute cholecystitis, we retrospectively reviewed the data of patients with primary carcinoma of the gallbladder. METHODOLOGY: The data of 86 patients with primary carcinoma of the gallbladder treated between 1979 and 1994 were compiled and reviewed. The patients were divided into 2 groups: Group 1 (with acute cholecystitis, 21 patients) and Group 2 (without cholecystitis, 65 patients). Clinicopathological comparisons were made and evaluated between these two groups RESULTS: The average age of Group 1 patients was older than that of Group 2 patients (75+/-2 years vs. 63+/-2 years; p<0.05). Three Group 1 patients presented with sepsis. The interval between the onset of symptoms and hospital admission in Group 2 patients was significantly (p<0.05) longer than that in Group 1 patients (243+/-95 days vs. 20+/-11 days). Leukocytosis (>11,000/mm3) was more common in Group 1 patients than in Group 2 patients (47.6% vs. 15.4%). Jaundice was more common in Group 2, and fever was common in Group 1. The majority of Group 2 gallbladder cancers were stage V (75.4%). In contrast, 52.4% of Group 1 gallbladder cancers were stage III and 38.1% were stage V. The 30-day postoperative mortality rate in Group 1 and Group 2 patients was 9.5% and 7.7%, respectively. The cumulative survival of Group 1 patients was not different from that of Group 2 patients (log-rank test, p>0.05). CONCLUSIONS: Age, the interval of symptoms prior to admission, the location of abdominal pain, fever, leukocytosis, and the absence of jaundice suggested the presence of acute cholecystitis in gallbladder carcinoma. A high index of suspicion of the disease, intraoperative examination of gallbladder specimens, and more aggressive surgical treatment may improve patient survival.  相似文献   
158.
This study examined the expression of fibroblast growth factor receptor 2 (FGFR 2) splice variants, IIIb and IIIc, in normal and malignant human oral keratinocytes and in normal oral fibroblasts by RT-PCR using both exon-specific primers and primers common to both FGFR 2 isoforms. Fibroblasts expressed exclusively FGFR 2/IIIc whilst the normal and malignant keratinocytes co-expressed FGFR 2/IIIb and FGFR 2/IIIc. Well-differentiated keratinocytes expressed proportionally more FGFR 2/IIIb than IIIc whereas the poorly-differentiated cells expressed more FGFR 2/IIIc than IIIb. The normal and malignant keratinocytes, but not fibroblasts, expressed an additional amplification product, which consisted of both IIIb and IIIc of FGFR 2 joined by an extra base pair and with the intronic sequence removed. The results indicate that the expression of FGFR 2 isoforms reflects the degree of cellular differentiation in normal and malignant human oral keratinocytes and that receptor complexes of FGFR 2/IIIb and IIIc may regulate ligand-receptor interactions.  相似文献   
159.
Replication forks formed in the absence of the tau subunit of the DNA polymerase III holoenzyme produce shorter leading and lagging strands than when tau is present. We show that one reason for this is that in the absence of tau, but in the presence of the gamma-complex, leading-strand synthesis is no longer highly processive. In the absence of tau, the size of the leading strand becomes proportional to the concentration of beta and inversely proportional to the concentration of the gamma-complex. In addition, the beta in the leading-strand complex is no longer resistant to challenge by either anti-beta antibodies or poly(dA):oligo(dT). Thus, tau is required to cement a processive leading-strand complex, presumably by preventing removal of beta catalyzed by the gamma-complex.  相似文献   
160.
The predominant early childhood education philosophy in the United States views formal academic instruction as inappropriate and harmful to the social development of young children. Chinese American immigrants to the United States, however, have been found to teach their young children in more formal ways, to be more directive, and to structure their children's use of time to a greater degree (C. S. Huntsinger, P. E. Jose, F.-R. Liaw, & W.-D. Ching, 1997). Forty European American (20 boys, 20 girls) and 36 2nd-generation Chinese American (18 boys, 18 girls) 1st- and 2nd-grade children and their mothers, fathers, and teachers participated in the Time 2 data collection of this longitudinal study to assess whether the formal academic environment provided by Chinese American parents is linked to poorer social adjustment in their children. Regressions showed that parents' work-oriented methods influenced academic performance but not social adjustment of their children.  相似文献   
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