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101.
Osteoclast-like giant-cell neoplasms of the urinary tract are rare. They are composed of ovoid or spindle-shaped mononuclear cells with evenly spaced osteoclast-like giant cells. Terminology, histogenesis, and biologic behavior of these tumors remain controversial. Six cases of osteoclast-like giant-cell neoplasms of the urinary tract were identified from the consultation files of two of the authors. Patients were all male and elderly (range 65-82), with the exception of one 39-year-old male. In all, 3/6 tumors developed in the bladder and 3/6 in the renal pelvis. Size ranged from 5 to 11 cm. One bladder and three renal pelvis tumors were high stage (pT3) at time of presentation. Adjacent to the osteoclast-like giant-cell neoplasm in the same specimen, all patients had urothelial carcinoma in situ and/or high-grade papillary urothelial carcinoma. Multinucleated cells had identical morphological and immunohistochemical properties of osteoclasts; positive for CD-68, LCA, CD51 and CD54, and negative for cytokeratins and EMA. Varying percentages of mononuclear cells expressed alpha-smooth muscle actin (4/6), desmin (1/6), S-100 (4/6), LCA (2/6) and CD68 (6/6). However, mononuclear cells were also positive for epithelial markers in 4/6 tumors (cytokeratins AE-1/AE-3, Cam 5.2, CK7 and/or EMA). p53 stained mononuclear tumor cells in three cases, paralleling the staining on the accompanying urothelial carcinoma. Ki-67 stained mononuclear tumor cells, but not osteoclast-like giant cells. Follow-up data were available in five cases. One patient developed recurrence of noninvasive urothelial carcinoma and is still alive. Four patients were dead due to disease within 15 months, three with distant metastases. The intimate association of these tumors with urothelial carcinoma along with their immunohistochemical profile supports an epithelial origin for the mononuclear cells and non-neoplastic reactive histiocytic lineage for the osteoclast-like giant cells. 相似文献
102.
用于杀虫剂评价的水池中无脊椎动物的群落结构及其种群动态 总被引:3,自引:0,他引:3
实验水池是评价杀虫剂效应和安全生的重要场所,水池中无脊椎动物群落结构和种群动态是评价杀虫剂的基础资料和考核指标,本文报告1992年至1993年在美国佛罗里达中部地区对应用于杀虫剂评价的实验水池中昆虫与其它无脊椎动物群落结构及其优势种的种群动态研究结果,用羽化诱捕、勺舀、网拉及挖取底物法,从实验水池中共采到昆虫与其它无脊椎动物50余类,其中,羽化诱捕到的昆虫中摇蚊占93.9%,蜉蝣目昆虫占4.6%, 相似文献
103.
Emotional abuse, self-blame, and self-silencing in women with irritable bowel syndrome 总被引:5,自引:0,他引:5
Ali A Toner BB Stuckless N Gallop R Diamant NE Gould MI Vidins EI 《Psychosomatic medicine》2000,62(1):76-82
OBJECTIVE: The purpose of this study was to investigate the presence of emotional abuse and two psychosocial constructs (self-blame and self-silencing) in a sample of women diagnosed with irritable bowel syndrome (IBS) relative to a comparison sample of women diagnosed with inflammatory bowel disease (IBD). METHODS: Women diagnosed with IBS (N = 25) were compared with women diagnosed with IBD (N = 25) on measures of history of abuse, self-blame, and self-silencing. RESULTS: It was found that women in the IBS sample scored significantly higher on emotional abuse, self-blame, and self-silencing than did women in the IBD sample. These three variables were also found to be significantly intercorrelated in both the IBS and IBD samples. Finally, emotional abuse was significantly higher in IBS patients than in IBD patients beyond the differences accounted for by physical and/or sexual abuse history. CONCLUSIONS: These findings empirically demonstrate an association between IBS and emotional abuse, as well as a possible connection with psychosocial variables, that may mediate the connection between emotional abuse and functional bowel symptoms. We suggest that these variables be further evaluated in the context of clinically relevant research on IBS. 相似文献
104.
To determine the effect of prostaglandin-synthesis inhibition on ureteral motility, isolated rings of sheep ureters were suspended for recording isometric tension in organ baths filled with Krebs-Henseleit solution. The non-steroidal anti-inflammatory drugs (NSAIDs) indomethacin and diclofenac sodium (10(-5) M) inhibited rhythmic ureteral motility by reducing frequency, amplitude and finally stopping contractions. Prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha and thromboxane B2 were determined by radioimmunoassay in the bathing solution before and after addition of NSAIDs. Peak contractile activity at 100 min of suspension was associated with increased concentration of all three prostanoids and 50 min after addition of indomethacin and diclofenac sodium when rhythmic contractions stopped, concentration dropped to low levels. The concentration of prostaglandins released into the organ bath were not quantitatively related to the frequency of contractions and therefore do not seem to affect pacemaker activity within ureteral smooth muscle but rather intercellular recruitment of myo-genically active fibres. These findings indicate that prostaglandins play a role in the motor control of the ureter, and that non-steroidal anti-inflammatory drugs exert an inhibitory action. 相似文献
105.
Eucaryotic Expression of the Nucleocapsid Protein Gene of Porcine Circovirus Type 2 and Use of the Protein in an Indirect Immunofluorescence Assay for Serological Diagnosis of Postweaning Multisystemic Wasting Syndrome in Pigs 下载免费PDF全文
Sbastien Racine Ali Kheyar Carl A. Gagnon Benoît Charbonneau Serge Dea 《Clinical and Vaccine Immunology : CVI》2004,11(4):736-741
The purpose of this study was to develop a sensitive, rapid, and inexpensive immunofluorescence assay (IFA) using a recombinant porcine circovirus type 2 (PCV2) nucleocapsid protein for the serological detection of PCV2-specific antibodies in pig sera. The viral nucleocapsid protein encoded by the PCV2 ORF2 gene has recently been identified as the most immunoreactive viral protein that carries type-specific antigenic determinants. The ORF2 sequence of the IAF-2897 strain of PCV2 has been cloned into a pCEP5 eucaryotic expression vector under the control of the cytomegalovirus promoter, downstream of a polyhistidine sequence tag. The recombinant plasmid was used in transfection experiments with human epithelial kidney 293 cells that were further tested, and positive expression of the viral nucleocapsid protein was confirmed by IFA and Western blotting. Strong, specific fluorescence was observed in the nuclei of transfected cells. Test specificity to PCV2 was verified with several related infectious agents. Sensitivity was compared to that of standard IFA using PCV2-infected cells by evaluating the reactivities of 44 field serum samples from pigs on farms with a porcine population suffering from postweaning multisystemic wasting syndrome. The recombinant nucleocapsid-based test was able to detect 15 more positive-testing pigs than the PCV2-based IFA. Therefore, the relative sensitivity of the latter test was estimated at only 57.1% compared to that of the recombinant nucleocapsid-based test. The recombinant fusion protein has been purified by affinity chromatography and is being used to develop further sensitive serological tests. 相似文献
106.
Ansar M Din MA Arshad M Sohail M Faiyaz-Ul-Haque M Haque S Ahmad W Leal SM 《European journal of human genetics : EJHG》2003,11(1):77-80
Autosomal recessive nonsyndromic deafness is one of the most frequent forms of inherited hearing impairment. Over 30 autosomal recessive nonsyndromic hearing loss loci have been mapped, and 15 genes have been isolated. Of the over 30 reported autosomal recessive nonsyndromic hearing loss (NSHL) loci, the typical phenotype is prelingual non-progressive severe to profound hearing loss with the exception of DFNB8, which displays postlingual onset and DFNB13, which is progressive. In this report we describe a large inbred kindred from a remote area of Pakistan, comprising six generations and segregating autosomal recessive nonsyndromic prelingual deafness. DNA samples from 24 individuals were used for genome wide screen and fine mapping. Linkage analysis indicates that in this family the NSHL locus, (DFNB35) maps to a 17.54 cM region on chromosome 14 flanked by markers D14S57 and D14S59. Examination of haplotypes reveals a region that is homozygous for 11.75 cM spanning between markers D14S588 and D14S59. A maximum two-point LOD score of 5.3 and multipoint LOD score of 7.6 was obtained at marker D14S53. The interval for DFNB35 does not overlap with the regions for DFNA9, DFNA23 or DFNB5. 相似文献
107.
Polyclonal anti-PSA is more sensitive but less specific than monoclonal anti-PSA: Implications for diagnostic prostatic pathology 总被引:3,自引:0,他引:3
Varma M Morgan M Jasani B Tamboli P Amin MB 《American journal of clinical pathology》2002,118(2):202-207
Prostate-specific antigen (PSA) production by nonprostatic tissues has been reported, casting doubts on its specificity. The immunohistochemical relative specificity and sensitivity of PSA expression using monoclonal and polyclonal anti-PSA was analyzed on 60 prostate carcinomas, 40 normal seminal vesicles, and 310 nonprostatic tumors. All nonprostatic tumors proved negative with both antibodies. However, 13 (32%) seminal vesicles showed immunoreactivity with polyclonal anti-PSA, but none showed immunoreactivity with the monoclonal antibody. The sensitivity of the 2 antibodies for prostate cancer varied with tumor grade. In Gleason pattern 3, both antibodies showed diffuse immunostaining in all cases. In Gleason pattern 5, polyclonal anti-PSA showed diffuse (>95%) tumor cell positivity in 18 cases (90%), while with the monoclonal antibody, 7 cases (35%) showed only focal (<10%) tumor cell immunoreactivity. Thus, monoclonal anti-PSA seems to be useful in small gland proliferations in which the differential diagnosis includes seminal vesicle, while for poorly differentiated neoplasms, polyclonal anti-PSA is considered superior. Sections of high-grade prostate cancer should be included as positive controls for PSA immunostaining. 相似文献
108.
The spectrum of renal neoplasms has expanded in recent years. Although most of the work taking place in this field has concerned malignant neoplasms of the kidney, there have been significant improvements in our knowledge of benign renal tumors and tumor-like lesions, especially in renal cell adenoma, renal oncocytoma, and renal angiomyolipoma. Awareness and knowledge of these benign lesions is important because they are often included in the differential diagnoses of malignant tumors, with which they may be confused both clinically and pathologically. The authors review the topic of benign renal neoplasms and tumor-like lesions that occur in adults, emphasizing some of the newly described aspects of these lesions. 相似文献
109.
Charlotte Charpentier Didier Laureillard Mustapha Sodqi Ali Si-Mohamed Marina Karmochkine Laurent Bélec Laurence Weiss Christophe Piketty 《Journal of clinical virology》2008,43(2):212-215
BACKGROUND: Salvage therapy based on foscarnet plus a thymidine analog is effective in patients with advanced-stage HIV disease and viruses harbouring multiple drug-resistance mutations. OBJECTIVE: To identify viral genetic determinants associated with the virological efficacy of foscarnet salvage therapy. STUDY DESIGN: Thirteen patients received foscarnet at a fixed dose of 80mg/kg twice daily for 14 days, in combination with zidovudine or stavudine. RESULTS: The baseline median HIV viral load and CD4 cell count were 5.10log(10)copies/ml and 23cells/mm(3), respectively. Following foscarnet therapy, viral load fell by a median of 1.84log(10)copies/ml (range: -0.29 to -2.82), and by at least 1log(10)copies/ml in 11 patients, all of whom harboured viruses with at least three thymidine-associated mutations (TAMs). The two patients with smaller declines in viral load (<0.50log(10)copies/ml) harboured viruses with only one or zero TAMs. CONCLUSIONS: These findings corroborate, in vivo, the impact of TAMs on HIV susceptibility to foscarnet. The virological response to foscarnet salvage therapy in multiclass-experienced patients may thus differ according to the number of TAMs. 相似文献
110.
Powel?KazanjianEmail author Wei?Wei Morton?Brown Tejal?Gandhi Kamal?Amin 《Journal of translational medicine》2005,3(1):40