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41.
The pre-transplantation goal of the urologist is the optimization of urinary tract condition. Therefore, urologic surgery may be needed before or after renal transplantation. We analyzed the results of urologic surgery performed because of de novo urologic diseases. Between January 1986 and January 2001, 281 patients underwent renal transplantation, and 23 urologic surgical procedures were performed on 21 transplant recipients before or after renal transplantation because of de novo urologic diseases. By review the major reasons for urologic surgery in recipients were polycystic kidney diseases, vesicoureteral reflux, and dysfunctional voiding disorders. Nineteen surgical corrective procedures were done average 2.9 months before transplantation. The mortality rate was 10.5%. Four patients underwent urologic surgery at an average 57.5 months after transplantation. We highlight the fact that patients with uremia are vulnerable to surgical complications, and conclude that more intensive longterm urologic follow-ups should be conducted on recipients.  相似文献   
42.
Hepatitis B virus (HBV) is one of the major causative agents of chronic liver diseases in Korea. HBV has been classified into 8 genotypes by a divergence of >8% in the entire genomic sequence, and have distinct geographic distributions. There are limited data on the relevance between HBV genotypes and clinical outcomes in Korea. To investigate the clinical feature relating to HBV genotype in Korea, a total 120 serum samples with HBsAg (65 from Seoul and 55 from the other city in Korea) were obtained from each 30 chronic HBV carriers with asymptomatic carrier (ASC), chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). HBV genotype was determined by either enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies against genotype-specific epitopes in the preS2-region or the direct sequencing of small S gene. HBV genotypes were determined in 105 (87.5%) of 120 samples. HBV genotype C was identified in all HBV carriers with ASC, CH, LC, and HCC. Genotypes A, B, D, E, F and G were not detected in any of them. Genotype C HBV prevails predominantly among chronic carriers of the virus in Korea, irrespective of their clinical stages of liver disease and geographic origin.  相似文献   
43.
In order to develop a structured and objective diagnostic instrument, authors completed: (1) the translation and back translation of the Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and Lifetime Version (K-SADS-PL) and (2) the examination of its validity and reliability of the K-SADS-PL-Korean version (K-SADS- PL) when used with Korean children. A total of 91 study subjects were recruited from child and adolescent psychiatry outpatient clinics. Clinical diagnoses were used as a gold standard for the examination of validity of K-SADS-PL-K. Consensual validity of threshold and sub-threshold diagnoses were good to excellent for attention-deficit/hyperactivity disorder (ADHD), fair for tic and oppositional defiant disorders, and poor to fair for anxiety and depressive disorders. Inter-rater and test-retest reliabilities were fair to excellent for ADHD and tic disorder. The significant correlations between the K-SADS-PL-K and Korean Child Behavior Checklist (K-CBCL) were found, which provided additional support for the concurrent validity of the K-SADS-PL-K. Sensitivities varied according to the diagnostic categories, but specificities remained high over all diagnoses, suggesting that the K-SADS-PL-K is a desirable confirmatory diagnostic tool. The results of this study suggest that the K-SADS-PL-K is an effective instrument for diagnosing major child psychiatric disorders, including ADHD, behavioral disorders and tic disorders in Korean children. Future studies will examine the validity and reliability of the K-SADS-PL-K in larger samples, including adolescents and community samples on a variety of child and adolescent psychiatric disorders.  相似文献   
44.
The purpose of this paper is to develop a method of eliminating CT image artifacts generated by objects extending outside the scan field of view, such as obese or inadequately positioned patients. CT projection data are measured only within the scan field of view and thus are abruptly discontinuous at the projection boundaries if the scanned object extends outside the scan field of view. This data discontinuity causes an artifact that consists of a bright peripheral band that obscures objects near the boundary of the scan field of view. An adaptive mathematical extrapolation scheme with low computational expense was applied to reduce the data discontinuity prior to convolution in a filtered backprojection reconstruction. Despite extended projection length, the convolution length was not increased and thus the reconstruction time was not affected. Raw projection data from ten patients whose bodies extended beyond the scan field of view were reconstructed using a conventional method and our extended reconstruction method. Limitations of the algorithm are investigated and extensions for further improvement are discussed. The images reconstructed by conventional filtered backprojection demonstrated peripheral bright-band artifacts near the boundary of the scan field of view. Images reconstructed with our technique were free of such artifacts and clearly showed the anatomy at the periphery of the scan field of view with correct attenuation values. We conclude that bright-band artifacts generated by obese patients whose bodies extend beyond the scan field of view were eliminated with our reconstruction method, which reduces boundary data discontinuity. The algorithm can be generalized to objects with inhomogeneous peripheral density and to true "Region of Interest Reconstruction" from truncated projections.  相似文献   
45.
P-selectin is an adhesion molecule, expressed at the surface of activated cells, that mediates the interaction of activated endothelial cells or platelets with leukocytes. P-selectin expression is increased in atherosclerotic plaques, and high plasma levels of this molecule have been observed in patients with unstable angina. We investigated the P-selectin gene as a possible candidate for myocardial infarction (MI). The P-selectin gene is situated on chromosome 1q21-q24, spans >50 kb and contains 17 exons. The sequences of the 5'-flanking region and exons of 40 alleles from patients with MI were screened for polymorphisms using polymerase chain reaction/single-strand conformation polymorphism (PCR-SSCP) and sequencing. Thirteen polymorphisms were identified: five in the 5'-flanking and eight in the exonic sequences. Four polymorphisms (Ser290Asn, Asn562Asp, Leu599Val and Thr715Pro) predicted a change in the amino acid sequence of the P- selectin protein. All P-selectin polymorphisms as well as a common E- selectin polymorphism, Ser128Arg which has been reported as being associated with an increased risk of premature coronary heart disease (CHD), and is in tight linkage disequilibrium with several P-selectin polymorphisms, were investigated in 647 patients with MI and 758 control subjects from four regions of France and Northern Ireland (the ECTIM study). The entire set of P-selectin polymorphisms provided a heterozygosity of 91%. The polymorphisms were tightly associated with one another and displayed patterns of linkage disequilibrium suggesting the existence of highly conserved ancestral haplotypes. The five polymorphisms in the 5'-flanking region of the gene were unrelated to MI or any relevant phenotype measured in the ECTIM study. We inferred that the four missense variants identified in the coding region predicted eight common forms of the P-selectin protein. The Pro715 allele which characterizes one of these forms was less frequent in France than in Northern Ireland ( P < 0.002) and in cases than in controls ( P < 0.002; P < 0.02 after correction for the number of tests). We conclude that the P-selectin gene is highly polymorphic and hypothesize that the Pro715 variant may be protective for MI. Whether this variant affects the properties of the P-selectin protein in a way which is compatible with this hypothesis needs to be checked experimentally.   相似文献   
46.
Previous studies have suggested that human follicular fluid contains factors that reduce the zona-binding capacity of spermatozoa. The present study provides further evidence of the existence of such factors. Using the hemizona binding assay (HZA), we have shown that the inhibitory effect of human follicular fluid on the zona-binding capacity of spermatozoa is concentration-dependent, an inhibitory effect being detected when the concentration of human follicular fluid was > or = 10%. A 1% concentration of human follicular fluid did not possess this inhibitory activity. Heating human follicular fluid at 56 degrees C for 30 min did not affect its inhibitory properties; treatment with proteinase-K abolished such inhibition. Human follicular fluid was fractionated sequentially by concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography and Superose-12 gel filtration. The zona binding inhibitory activity resided in the fraction which bound to the lectin and Mono Q column and contained molecules with native molecular weights of 32 and 192 kDa. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein remained as a single molecular species under denaturing conditions. We conclude that two glycoproteins were responsible for the zona binding inhibitory activity of human follicular fluid. The physiological role of these factors remains unclear.   相似文献   
47.
Fifty women with polycystic ovaries took part in a prospective randomized study. All women required treatment by in-vitro fertilization (IVF) for reasons other than anovulation. They had all previously undergone ovarian stimulation with gonadotrophin therapy which had failed to result in pregnancy or had been abandoned due to high risk of developing ovarian hyperstimulation syndrome (OHSS). Twenty-five women were treated by long-term pituitary desensitization followed by gonadotrophin therapy, oocyte retrieval and embryo transfer (group 1). Twenty-five women underwent laparoscopic ovarian electrocautery after pituitary desensitization followed by gonadotrophin therapy, oocyte retrieval and embryo transfer (group 2). A significantly higher number of women in group 1 had to have the treatment cycle abandoned due to impending or actual OHSS, determined by endocrine and clinical findings. In addition, the development of moderate or severe OHSS in completed cycles was higher in group 1. The pregnancy rate and miscarriage rates in the two treatment groups were similar. The authors propose that laparoscopic ovarian electrocautery is a potentially useful treatment for women who have previously had an IVF treatment cycle cancelled due to risk of OHSS or who have suffered OHSS in a previous treatment cycle.   相似文献   
48.
49.
Matrix metalloproteinases (MMPs) have been implicated in physiological cartilage matrix remodelling as well as in pathological and invasive extracellular matrix remodelling of tissue. Age-related changes in the gene expression patterns of MMPs in mandibular condylar cartilages (MCCs) were analysed. We examined the gene expression patterns of Mmp-8 and -13 and their substrates, Col1a1, Col2a1 and Col10a1, in MCC of growing and ageing rats. Temporomandibular joints of male Wistar rats aged 4, 8, 16 and 32 weeks were subjected to in situ hybridization analysis. Histologically, MMCs showed characteristics of growth plate cartilage at ages 4 and 8 weeks, and more closely resembled articular cartilage thereafter. Mmp-8 was expressed in the cells in all cartilaginous cell layers at ages 4 and 8 weeks, and then was localized only in the mature cells at ages 16 and 32 weeks. Whereas Mmp-13 expression was limited to the lowermost hypertrophic chondrocytes in the growth stage, mature chondrocytes instead of hypertrophic chondrocytes expressed Mmp-13 in adult non-hypertrophic MCC. Because Mmp-8 and -13 expression overlapped with Col2a1 and Col10a1, chondrocytes could play a pivotal role in degradation as well as production of the cartilaginous matrix in MCC.  相似文献   
50.
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