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排序方式: 共有1453条查询结果,搜索用时 31 毫秒
1.
Primary cutaneous anaplastic large cell lymphomas with 6p25.3 rearrangement exhibit particular histological features 下载免费PDF全文
2.
Leyi Wang Saraswathi Lanka Debbie Cassout Nohra E. Mateus‐Pinilla Ganwu Li William C. Wilson Dongwan Yoo Paul Shelton Richard L. Fredrickson 《Transboundary and Emerging Diseases》2019,66(5):1809-1820
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year. 相似文献
3.
Alicia Gómez-Barrio David Montero-Pereira Juan J. Nogal-Ruiz José A. Escario Susana Muelas-Serrano Vladimir V. Kouznetsov Leonor Y. Vargas Méndez Juan M. Urbina Gonzáles Carmen Ochoa 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(1):73-78
A study of some antiparasitic properties of several homoallylamines and related tetrahydroquinolines and quinolines, previously
described, was carried out using in vitro activity assays against the epimastigote form of Trypanosoma cruzi and against Trichomonas vaginalis. Unspecific cytotoxicity against murine macrophages was also studied. Although the antichagasic and trichomonacidal activities
are not comparable to those of the standard drugs, nifurtimox and metronidazole, some of the compounds exhibit an interesting
specific antiparasitic activity. 相似文献
4.
The effect of different androgens and estradiol on pituitary responsiveness to growth hormone releasing hormone was studied in intact and orchidectomized adult male Wistar rats, by injecting subcutaneously immediately after orchidectomy for two weeks with testosterone, dihydrotestosterone, 5-alpha androstane, 3-alpha,17 beta-diol or estradiol dissolved in olive oil (in doses of 0.2 or 2.0 mg.kg-1.day-1) or vehicle. Pituitary responsiveness was tested in pentobarbital anaesthetized rats by measuring growth hormone plasma levels at different times after administration of growth hormone releasing hormone (1-29) NH2. We found that: (a) High doses of testosterone, dihydrotestosterone and 5-alpha androstane, 3-alpha,17 beta-diol restored gonadotropin plasma concentrations and organ weights altered by orchidectomy; (b) both pituitary growth hormone content and concentration remained unaffected after orchidectomy or androgen replacement and decreased significantly after estradiol injection; (c) orchidectomy significantly reduced growth hormone-stimulated growth hormone releasing hormone secretion; (d) treatment with 5-alpha androstane,3-alpha,17 beta-diol increased more than testosterone or dihydrotestosterone both the peak concentration and the mean growth hormone secretion after growth hormone releasing hormone stimulation; (e) no differences were observed in the treatment with testosterone or dihydrotestosterone; (f) estradiol given at a dose of 0.2 mg.kg-1.day-1 increased pituitary responsiveness to growth hormone releasing hormone.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Tony M. Keaveny Tania P. Pinilla R. Paul Crawford David L. Kopperdahl Albert Lou 《Journal of orthopaedic research》1997,15(1):101-110
We sought to quantify the systematic and random errors associated with-artifacts in the platens compression test for trabecular bone. Our hypothesis was that while errors may depend on anatomic site, they do not depend on apparent density and therefore have substantial random components. Trabecular bone specimens were first tested nondestructively using newly developed accurate protocols and then were tested again using the platens compression test. Percentage differences in modulus between the techniques (bovine) proximal tibia [n = 18] and humerus [n = 17] and human lumbar spine, [n = 9] were in the range of 4-86%. These differences did not depend on anatomic site (p = 0.21) and were only weakly dependent on apparent density and specimen aspect ratio (r2 < 0.10). The mean percentage difference in modulus was 32.6% representing the systematic component of the end-artifact error. Neglecting the minor variations explained by density and specimen size (approximately 10%), an upper bound on the random error from end-artifacts in this experiment was taken as the SD of the modulus difference (±18.2%). Based on a synthesis of data taken from this study and from the literature, we concluded that the systematic underestimation error in the platens compression test can be only approximated and is in the range of 20-40%; the substantial random error (±12.5%) confounds correction, particularly when the sample size is small. These errors should be considered when interpreting results from the platens test, and more accurate testing techniques should be used when such errors are not acceptable. 相似文献
6.
Joaquim Ferreira MD João Maia Silva MD Rita Freire BS João Pignatelli MD Leonor Correia Guedes MD Alexandra Feijó MD Mário Miguel Rosa MD Miguel Coelho MD João Costa MD Ana Noronha BS Russell Hewett MD A. Marques Gomes PhD J.L. Cirne de Castro MD Olivier Rascol PhD Cristina Sampaio PhD 《Movement disorders》2007,22(10):1471-1475
Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies. 相似文献
7.
J C Pinilla B Webster M Baetz B Reeder S Hattori L Liu 《JPEN. Journal of parenteral and enteral nutrition》1992,16(5):408-412
The objective of this study was to evaluate body composition as measured by bioelectric impedance analysis using splints and body positions differing from the standard supine position. Forty-three patients, randomized into two groups of different body positions, and 101 healthy volunteers were prospectively studied. Resistance and reactance of body tissues were measured by bioelectric impedance analysis. Body composition is described by a three-compartment model composed of body fat, body cell mass, and extra cellular mass. The patients were measured in the standard supine position and then randomized into two groups. They were then remeasured with the appropriate splinting device or position change. Volunteers were measured in the standard supine position and all four alternative positions. There was a statistically significant difference demonstrated in whole body resistance, whole body reactance, body cell mass, and the ratio of extracellular mass to body cell mass in some body positions. The percentage of change with different body positions and splints, when compared with the standard supine position, was generally below 2%, a clinically insignificant difference. We conclude that the reliability of resistance and reactance as measured by bioelectric impedance analysis is clinically valid using any of the tested body positions and/or splints. The three-compartment model may be a useful concept to measure body composition changes in both healthy and sick persons. 相似文献
8.
Characterization of human papillomavirus infection,P53 and Ki-67 expression in cervix cancer of Mozambican women 总被引:3,自引:0,他引:3
Carrilho C Gouveia P Cantel M Alberto M Buane L David L 《Pathology, research and practice》2003,199(5):303-311
In this study, we aimed at evaluating the distribution of HPV types and the expression of P53 and Ki-67 in cervix carcinomas of Mozambican women. Fourty-seven invasive carcinomas, 10 CIN III, and 10 normal cervix were studied. P53 and Ki-67 expression was examined immunohistochemically. HPV infection and HPV types were detected by PCR (GP5+/bio-GP6+) and enzyme-immunoassay, respectively. Expression of P53 and Ki-67 and detection of HPV were as follows: normal cervix--0%, 10%, and 0%, respectively; CIN III--10%, 0%, and 100%, respectively; invasive carcinomas--50%, 55.5%, and 70%, respectively. HPV 16 was identified in 54% of invasive carcinomas, HPV 31, 33, 35, and 45 in 23%, "unidentified" HPV in 19%, and HPV 18 in 4% of invasive carcinomas. No significant associations were observed between P53 expression, Ki-67 expression, and HPV infection. In conclusion, we observed a high frequency of HPV infection in CIN III lesions and invasive carcinomas from Mozambican women, with HPV 16 representing the most frequent viral type. HPV status was not related to P53 and Ki-67 expression. Both P53 and Ki-67 are associated with invasive cervix carcinomas, mainly of the squamous keratinizing histotype. 相似文献
9.
New microsatellite multiplex PCR for Candida albicans strain typing reveals microevolutionary changes 总被引:4,自引:0,他引:4 下载免费PDF全文
Sampaio P Gusmão L Correia A Alves C Rodrigues AG Pina-Vaz C Amorim A Pais C 《Journal of clinical microbiology》2005,43(8):3869-3876
Five new microsatellite loci were described and characterized for use as molecular markers for the identification and genetic differentiation of Candida albicans strains. Following the typing of 72 unrelated clinical isolates, the analysis revealed that they were all polymorphic, presenting from 5 to 30 alleles and 8 to 46 different genotypes. The discriminatory power obtained by combining the information generated by three microsatellites used in a multiplex PCR amplification strategy was 0.99, the highest ever reported. The multiplex PCR was later used to test a total of 114 C. albicans strains, including multiple isolates from the same patient collected from different body locations and along episodes of vulvovaginal infections. Three different scenarios for strain relatedness were identified: (i) different isolates that were revealed to be the same strain, (ii) isolates that were the same strain but that apparently underwent a process of microevolution, and (iii) isolates that corresponded to different strains. Analysis of the microevolutionary changes between isolates from recurrent infections indicated that the genotype alterations observed could be the result of events that lead to the loss of heterozygosity (LOH). In one case of recurrent infection, LOH was observed at the CAI locus, and this could have been related to exposure to fluconazole, since such strains were exposed to this antifungal during treatment. The analysis of microsatellites by a multiplex PCR strategy was found to be a highly efficient tool for the rapid and accurate differentiation of C. albicans strains and adequate for the identification of fine microevolutionary events that could be related to strain microevolution in response to environmental stress conditions. 相似文献
10.
Ignacio Prieto Charles Tease Nieves Pezzi José M. Buesa Sagrario Ortega Leonor Kremer Alicia Martínez Carlos Martínez-A Maj A. Hultén José L. Barbero 《Chromosome research》2004,12(3):197-213
Cohesins are chromosomal proteins that form complexes involved in the maintenance of sister chromatid cohesion during division of somatic and germ cells. Three meiosis-specific cohesin subunits have been reported in mammals, REC8, STAG3 and SMC1 beta; their expression in mouse spermatocytes has also been described. Here we studied the localization of different meiotic and mitotic cohesin components during prophase I in human and murine female germ cells. In normal and atretic human fetal oocytes, from leptotene to diplotene stages, REC8 and STAG3 colocalize in fibers. In murine oocytes, SMC1beta, SMC3 and STAG3 are localized along fibers that correspond first to the chromosome axis and then to the synaptonemal complex in pachytene. Mitotic cohesin subunit RAD21 is also found in fibers that decorate the SC during prophase I in mouse oocytes, suggesting a role for this cohesin in mammalian sister chromatid cohesion in female meiosis. We observed that, unlike human oocytes, murine synaptonemal complex protein SYCP3 localizes to nucleoli throughout prophase I stages, and centromeres cluster in discrete locations from leptotene to dictyate. At difference from meiosis in male mice, the cohesin axis is progressively lost during the first week after birth in females with a parallel destruction of the axial elements at dictyate arrest, demonstrating sexual dimorphism in sister chromatid cohesion in meiosis. 相似文献