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91.
Chronic inflammation is a common feature of end-stage renal disease, which carries a heightened risk of atherosclerosis and other co-morbid conditions. Dialysis treatment per se can bring additional risk factors for inflammation, such as increased risk of local graft and fistula infections, impure dialysate or bio-incompatible membranes. Our study was designed to determine whether a hemodialysis session leads to an acute substantial alteration in the plasma levels of the proinflammatory cytokines interleukin (IL)-6, IL-1beta and tumor necrosis factor (TNF)-alpha, the T-lymphocyte activation factor soluble IL-2 receptor (sIL-2R), and an inflammation mediator and chemotactic granulocyte factor, IL-8, in end-stage renal disease patients receiving chronic intermittent HD. In this study, 21 (12 male/nine female) patients undergoing chronic hemodialysis were enrolled. The acute effect of a hemodialysis session on serum cytokine concentrations was assessed by comparison of pre-hemodialysis and post-hemodialysis determinations. Serum IL-1beta, sIL-2R, IL-6, IL-8 and TNF-alpha levels were determined with chemiluminescence enzyme immunometric assays. A significant difference was not observed for IL-1beta, IL-6, TNF-alpha, and sIL-2R concentrations in pre-hemodialysis and post-hemodialysis specimens (p>0.05). Serum median (25th-75th percentiles) IL-8 concentration was 69.4 (34.9-110.3) pg/ml before hemodialysis, and decreased to 31.5 (18.0-78.8) pg/ml following hemodialysis (p: 0.006). Clearance of IL-8 increased by 0.47+/-0.08 pg/ml for each unit increase in pre-dialysis IL-8 (p<0.001) and decreased by 5.63+/-2.59 pg/ml for each unit increase in pre-dialysis urea mmol/l (p<0.05). In conclusion, the results of our study demonstrate that a hemodialysis session markedly decreases IL-8 concentration, which is significantly affected by pre-dialysis concentrations, indicating that removal of IL-8 is a concentration gradient-dependent action, but does not change the serum levels of IL-1beta, sIL-2R, IL-6, and TNF-alpha, underlining importance of the structural characteristics of the molecules.  相似文献   
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Familial intestinal polyatresia (FIPA) is a rare autosomal recessive disorder. In this article we present a new prenatally diagnosed case with FIPA from consanguineous parents with two affected daughters. The fourth pregnancy was diagnosed prenatally with FIPA at 18 weeks sonographically and these findings were confirmed by postmortem examination.  相似文献   
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Report of two cases with Van der Woude syndrome: a child and her mother: Congenital pits of the lower lip are rare malformations. They are closely associated with cleft lip (CL), cleft lip/palate (CL/CP) or isolated cleft palate (CP) and if so this condition is known as Van der Woude syndrome, which is inherited in an autosomal dominant fashion with high penetrance. Two individuals, one with lower lip pits and cleft palate and the other with isolated lower lip pit from the same family are described. Autosomal dominant pattern of inheritance was observed in this family and treatment consisted of complete removal of sinus tracts in one patient. Pathological features of sinus tracts consisted of stratified nonkeratinized squamous epithelium and a lamina propria of dense connective tissue. Importance of genetic counseling is emphasized as at least half of gene carriers have some kind of clefting.  相似文献   
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A new approach to sequence comparison: normalized sequence alignment   总被引:3,自引:0,他引:3  
The Smith-Waterman algorithm for local sequence alignment is one of the most important techniques in computational molecular biology. This ingenious dynamic programming approach was designed to reveal the highly conserved fragments by discarding poorly conserved initial and terminal segments. However, the existing notion of local similarity has a serious flaw: it does not discard poorly conserved intermediate segments. The Smith-Waterman algorithm finds the local alignment with maximal score but it is unable to find local alignment with maximum degree of similarity (e.g. maximal percent of matches). Moreover, there is still no efficient algorithm that answers the following natural question: do two sequences share a (sufficiently long) fragment with more than 70% of similarity? As a result, the local alignment sometimes produces a mosaic of well-conserved fragments artificially connected by poorly-conserved or even unrelated fragments. This may lead to problems in comparison of long genomic sequences and comparative gene prediction as recently pointed out by Zhang et al. (Bioinformatics, 15, 1012-1019, 1999). In this paper we propose a new sequence comparison algorithm (normalized local alignment ) that reports the regions with maximum degree of similarity. The algorithm is based on fractional programming and its running time is O(n2log n). In practice, normalized local alignment is only 3-5 times slower than the standard Smith-Waterman algorithm.  相似文献   
97.
OBJECTIVE: To evaluate the significance of nuclear morphometry in predicting the clinical course in superficial (pTa and pT1) bladder cancer. STUDY DESIGN: The study included 73 patients with superficial transitional cell carcinoma of the bladder who were followed for a median of 21 months (range, 1-90). Nuclear morphometry was performed by a computer-assisted image analyzer system on hematoxylineosin-stained histologic sections and characterized by five nuclear variables: area, perimeter, major and minor diameter, and form factor. Patient charts and microscopic slides were reviewed to record tumor stage, grade and size. Tumor proliferative activity was assessed by immunohistochemical staining with Ki-67 antibody. RESULTS: None of the morphometric variables showed a significant relation to tumor progression and recurrence. Higher values of mean nuclear area, perimeter, and major and minor diameter were significantly related to higher grade and proliferative activity. Mean nuclear area and minor diameter were associated with advanced stage. Of established prognostic factors, only histologic grade was significant in predicting progression. CONCLUSION: The results suggest that nuclear morphometry may be valuable in determining proliferative activity and may be well correlated with histologic grade in superficial bladder cancer. However, like many other potential prognostic factors, it seems to be unreliable in predicting clinical behavior.  相似文献   
98.
OBJECTIVE: To assess the capacity of the percentage carcinoma method to predict tumor volume in cervical carcinoma and generate a mathematical equation for calculation of tumor volume. STUDY DESIGN: Thirteen radical hysterectomy specimens were studied. The actual tumor volume was assessed by stereology. A factor was generated by the formula tumor volume = factor x percentage carcinoma x number of blocks. The percentage carcinoma was calculated by the grid method. Then tumor volume was estimated by the same formula. The relationship between actual and estimated tumor volumes was analyzed by Spearman's correlation. RESULTS: Correlation of the tumor volumes assessed by the two methods was excellent (r = .945) and statistically significant (P = .01). CONCLUSION: Percentage carcinoma assessed by the grid ratio method is highly predictive of tumor volume, but care must be taken not to overstate the importance of our results due to the small number of patients. The prediction of outcome in cervical carcinoma by means of percentage carcinoma should be evaluated in large clinical studies.  相似文献   
99.
To investigate the origin and nature of the signals responsible for specification of the dermatomal lineage, excised axial organs in 2-day-old chick embryos were replaced by grafts of the dorsal neural tube, or the ventral neural tube plus the notochord, or aggregates of cells engineered to produce Sonic hedgehog (Shh), Noggin, BMP-2, Wnt-1, or Wnt-3a. By E10, grafts of the ventral neural tube plus notochord or of cells producing Shh led to differentiation of cartilage and muscles, and an impaired dermis derived from already segmented somites. In contrast, grafts of the dorsal neural tube, or of cells producing Wnt-1, triggered the formation of a feather-inducing dermis. These results show that the dermatome inducer is produced by the dorsal neural tube. The signal can be Wnt-1 itself, or can be mediated, or at least mimicked by Wnt-1.  相似文献   
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