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101.
102.
Ruth Tachezy Eva Hamsikova Jaroslav Valvoda Marc Van Ranst Jan Betka Robert D. Burk Vladimir Vonka 《Journal of medical virology》1994,42(1):52-59
Recurrent respiratory papillomatosis (RRP) is the most common benign tumour of the larynx, affecting both children and adults. We present a series of 25 patients, including 10 cases of juvenile multiple, 8 cases of adult solitary, and 7 cases of adult multiple RRP. Biopsy tissue from each patient was screened by Southern blot hybridization and polymerase chain reaction for the presence of human papillomavirus (HPV) DNA. Sera from patients and age- and sex-matched controls were tested for the presence of HPV-specific antibodies using a synthetic pep-tide derived from the minor capsid protein (L2) of HPV 6/11. By Southern blot hybridization and/or polymerase chain reaction, biopsies from all patients were positive for HPV 6/11 DNA. There was no difference in antibody response between cases and controls. Female cases and controls had significantly higher antibody titers than male subjects. A correlation was observed between the HPV-specific antibody level and the number of surgery-necessitating recurrences. © 1994 Wiiey-Liss, Inc. 相似文献
103.
104.
Constance Schrander-Stumpel Christine de Die-Smulders Marc de Krom Suzanne Schyns-Fleuren Ben Hamel Deni Jaeken Jean-Pierre Fryns 《Clinical genetics》1993,43(6):303-308
Schrander-Stumpel C, de Die-Smulders C, de Krom M, Schyns-Fleuren S, Hamel B, Jaeken D, Fryns J-P. Marden-Walker syndrome: case report, literature review and nosologic discussion.
Clin Genet 1993: 43: 303–308. © Munksgaard, 1993
The Marden-Walker syndrome is characterized by psychomotor retardation, a mask-like face with blepharophimosis, micrognathia and a high-arched or cleft palate, low-set ears, kyphoscoliosis and joint contractures. We report on a male patient with the clinical features of the syndrome. In addition, he had a Dandy-Walker malformation with hydrocephalus and vertebral abnormalities. During pregnancy, there were feeble fetal movements and polyhydramnios. We propose that Marden-Walker syndrome is one of the etiologic possibilities in children with the heterogeneous fetal a(hypo)kinesia deformation sequence (FADS). Differential diagnosis is discussed. The etiology is probably heterogeneous. 相似文献
Clin Genet 1993: 43: 303–308. © Munksgaard, 1993
The Marden-Walker syndrome is characterized by psychomotor retardation, a mask-like face with blepharophimosis, micrognathia and a high-arched or cleft palate, low-set ears, kyphoscoliosis and joint contractures. We report on a male patient with the clinical features of the syndrome. In addition, he had a Dandy-Walker malformation with hydrocephalus and vertebral abnormalities. During pregnancy, there were feeble fetal movements and polyhydramnios. We propose that Marden-Walker syndrome is one of the etiologic possibilities in children with the heterogeneous fetal a(hypo)kinesia deformation sequence (FADS). Differential diagnosis is discussed. The etiology is probably heterogeneous. 相似文献
105.
M. John Hicks Victor A. Saldivar Murali M. Chintagumpala Marc E. Horowitz Linda D. Cooley James P. Barrish Edith P. Hawkins Claire Langston 《Ultrastructural pathology》1995,19(5):395-400
Malignant melanoma of soft parts (MMSP) was originally described as a distinct entity by Enzinger in 1965 and was termed “clear cell sarcoma of tendons and aponeuroses” because of its association with tenosynovial structures. It has been shown immunophenotypically and ultrastructurally that this tumor is derived from neuroectoderm and shares a number of features with cutaneous melanoma. Over 95% of MMSPs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of MMSP of the head and neck region involving the posterior cervical region in a 15-year-old Hispanic male and reviews the literature on MMSP. Ultrastructural examination showed rudimentary cell attachments, smooth cell membranes, discontinuous basal lamina, scanty glycogen, and occasional premelanosomes in some tumor cells. Cytogenetic analysis showed a reciprocal translocation between the long arms of chromosomes 12 and 22 [t(12:22)(q13;q12.2)], characteristic for MMSP and not seen in cutaneous melanoma. Survival in MMSP has been correlated with tumor size, tumor necrosis, and ploidy status. Overall reported clinical outcome for this tumor is as follows: died of disease, 45%; alive with disease, 23%; no evidence of disease, 30%; and died of other causes, 2%. MMSP represents a distinct entity with a characteristic ultrastructural appearance and a tumor defining cytogenetic translocation. 相似文献
106.
Molecular epidemiology of Pseudomonas aeruginosa colonization in a burn unit: persistence of a multidrug-resistant clone and a silver sulfadiazine-resistant clone 总被引:3,自引:0,他引:3 下载免费PDF全文
Pirnay JP De Vos D Cochez C Bilocq F Pirson J Struelens M Duinslaeger L Cornelis P Zizi M Vanderkelen A 《Journal of clinical microbiology》2003,41(3):1192-1202
To study the epidemiology of Pseudomonas aeruginosa colonization in a 32-bed burn wound center (BWC), 321 clinical and 45 environmental P. aeruginosa isolates were collected by prospective surveillance culture over a 1-year period and analyzed by serotyping, drug susceptibility testing, and amplified fragment length polymorphism (AFLP) analysis. Among 441 patients treated at the center, 70 (16%) were colonized with P. aeruginosa, including 12 (17%) patients who were colonized on admission and 58 (83%) patients who acquired the organism during their stay. Of the 48 distinct AFLP genotypes found, 21 were found exclusively in the environment, 15 were isolated from individual patients only, and 12 were responsible for the colonization of 57 patients, of which 2 were also isolated from the environment, but secondary to patient carriage. Polyclonal P. aeruginosa colonization with strains of two to four genotypes, often with different antibiotic susceptibility patterns, was observed in 19 patients (27%). Two predominant genotypes were responsible for recurrent outbreaks and the colonization of 42 patients (60% of all colonized patients). The strain with one of those genotypes appeared to be endemic to the BWC and developed multidrug resistance (MDR) at the end of the study period, whereas the strain with the other genotype was antibiotic susceptible but resistant to silver sulfadiazine (SSD(r)). The MDR strain was found at a higher frequency in sputum samples than the SSD(r) strain, which showed a higher prevalence in burn wound samples, suggesting that anatomic habitat selection was associated with adaptive resistance to antimicrobial drugs. Repeated and thorough surveys of the hospital environment failed to detect a primary reservoir for any of those genotypes. Cross-acquisition, resulting from insufficient compliance with infection control measures, was the major route of colonization in our BWC. In addition to the AFLP pattern and serotype, analysis of the nucleotide sequences of three (lipo)protein genes (oprI, oprL, and oprD) and the pyoverdine type revealed that all predominant strains except the SSD(r) strain belonged to recently identified clonal complexes. These successful clones are widespread in nature and therefore predominate in the patient population, in whom variants accumulate drug resistance mechanisms that allow their transmission and persistence in the BWC. 相似文献
107.
Diestra JE Scheffer GL Català I Maliepaard M Schellens JH Scheper RJ Germà-Lluch JR Izquierdo MA 《The Journal of pathology》2002,196(2):213-219
The expression and cellular localization of angiotensin II (Ang II) and AT(1) receptor proteins were examined in the normal human prostate and benign prostatic hyperplasia (BPH) by immunohistochemistry. In the normal prostate, Ang II immunoreactivity was localized to the basal layer of the epithelium and AT(1) receptor immunostaining was found predominantly on stromal smooth muscle and also on vascular smooth muscle of prostatic blood vessels. Ang II immunoreactivity was markedly increased in hyperplastic acini in BPH compared with acini in the normal prostate (normal: 7.4+/-0.2%, n=5 vs. BPH: 22.7+/-1.9%, n=5, p<0.001). However, AT(1) receptor immunoreactivity was significantly decreased in BPH compared with the normal prostate [normal: 16.4+/-2.2%, n=4 vs. BPH: 9.4+/-1.3%, n=5, p<0.05 (p=0.025)]. The present study demonstrates the presence of Ang II peptide in the basal layer of the epithelium and AT(1) receptors on stromal smooth muscle, suggesting that Ang II may mediate paracrine functions on cellular growth and smooth muscle tone in the human prostate. Furthermore, AT(1) receptor down-regulation in BPH may be due to receptor hyperstimulation by increased local levels of Ang II in BPH. These data extend previous findings in support of the novel concept that overactivity of the renin-angiotensin system (RAS) may be involved in the pathophysiology of BPH. 相似文献
108.
To date, there are no proven vaccines against any form of leishmaniasis. The development of live attenuated vectors shows promise in the field of Leishmania vaccination because these organisms mimic more effectively the course of real infections and can elicit potent activation of the immune system. In the present study, we investigated the potential of a parasitic protozoan that is nonpathogenic to humans, Leishmania tarentolae, as a live candidate vaccine that efficiently targets dendritic cells and lymphoid organs, thus enhancing antigen presentation and consequently influencing the magnitude and quality of T-cell immune responses. We demonstrated that L. tarentolae activates the dendritic cell maturation process and induces T-cell proliferation and the production of gamma interferon, thus skewing CD4(+) T cells toward a Th1 cell phenotype. More importantly, we found that a single intraperitoneal injection of L. tarentolae could elicit a protective immune response against infectious challenge with Leishmania donovani in susceptible BALB/c mice. These results suggest that the use of L. tarentolae as a live vaccine vector may represent a promising approach for improving the effectiveness and safety of candidate live vaccines against Leishmania infections and possibly other intracellular pathogens for which T-cell mediated responses are critical for the development of protective immunity. 相似文献
109.
Guarner J Greer PW Whitney A Shieh WJ Fischer M White EH Carlone GM Stephens DS Popovic T Zaki SR 《American journal of clinical pathology》2004,122(5):754-764
Neisseria meningitidis remains the leading cause of fatal sepsis. Cultures may not be available in fulminant fatal cases. An immunohistochemical assay for N meningitidis was applied to formalin-fixed samples from 14 patients with meningococcal disease. Histopathologic findings in 12 fatal cases included interstitial pneumonitis, hemorrhagic adrenal glands, myocarditis, meningitis, and thrombi in the glomeruli and choroid plexus. Meningeal inflammation was observed in 6 patients. Skin biopsies of 2 surviving patients showed leukocytoclastic vasculitis and cellulitis. By using immunohistochemical analysis, meningococci and granular meningococcal antigens were observed inside monocytes, neutrophils, and endothelial cells or extracellularly. By using real-time polymerase chain reaction (PCR) on formalin-fixed tissue samples, meningococcal serogroup determination was possible in 11 of 14 cases (8 serogroup C, 2 Y, and 1 B). Diagnosis and serogrouping of N meningitidis can be performed using immunohistochemical analysis and PCR on formalin-fixed tissue samples. Immunohistochemical analysis determined the distribution of meningococci and meningococcal antigens in tissue samples, allowing better insights into N meningitidis pathogenesis. 相似文献
110.