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排序方式: 共有387条查询结果,搜索用时 15 毫秒
41.
Kássio Duan Albani Willian Mauricio Radavelli João Ricardo de Souza Rhayana K. Grosskopf Josue Pires Topazio Leandro Sâmia Lopes Julcemar Dias Kessler Alexandre Alberto Tonin Diego de Córdova Cucco Aleksandro Schafer Da Silva 《Comparative clinical pathology》2014,23(2):475-476
Parasitic diseases affecting goats are able to cause major economic losses, standing out, among them, the lice infestation. According to the literature, lice can act as vectors of other diseases, including the ones caused by blood protozoan. In this sense, this survey study aimed to assess the ectoparasites of goats in the west region of Santa Catarina (SC). Two hundred seventeen goats from 24 different rural properties located in 17 towns in SC were examined. From them, ectoparasites were collected and evaluated in laboratory, where the parasitological classification was performed. In 13 properties, it was possible to identify ectoparasites. Damalinia caprae lice were observed in 126 animals (58 %), while Linognathus stenopsis were found in 10 animals (4.6 %). It is noteworthy that, in these properties, all the animals were under lice parasitism, independent of sex or age. The goats had peeling skin, particularly in the back region (lumbar). All of the 24 properties evaluated were reported having problems with lice in different seasons of the year, even under regular treatment with cypermethrin (spraying). Based on our findings, it was possible to conclude that D. caprae is the major ectoparasite of goats in the investigated area. 相似文献
42.
Carolina Maso Viegas Anelise Miotti Tonin ?ngela Zanatta Bianca Seminotti Estela Natacha Brandt Busanello Carolina Gon?alves Fernandes Alana Pimentel Moura Guilhian Leipnitz Moacir Wajner 《Metabolic brain disease》2012,27(4):521-530
Ornithine, ammonia and homocitrulline are the major metabolites accumulating in hyperornithinemia-hyperammonemia-homocitrullinuria syndrome, a genetic disorder characterized by neurological regression whose pathogenesis is still not understood. The present work investigated the in vivo effects of intracerebroventricular administration of ornithine and homocitrulline in the presence or absence of hyperammonemia induced by intraperitoneal urease treatment on a large spectrum of oxidative stress parameters in cerebral cortex from young rats in order to better understand the role of these metabolites on brain damage. Ornithine increased thiobarbituric acid-reactive substances (TBA-RS) levels and carbonyl formation and decreased total antioxidant status (TAS) levels. We also observed that the combination of hyperammonemia with ornithine resulted in significant decreases of sulfhydryl levels, reduced glutathione (GSH) concentrations and the activities of catalase (CAT) and glutathione peroxidase (GPx), highlighting a synergistic effect of ornithine and ammonia. Furthermore, homocitrulline caused increases of TBA-RS values and carbonyl formation, as well as decreases of GSH concentrations and GPx activity. Hcit with hyperammonemia (urease treatment) decreased TAS and CAT activity. We also showed that urease treatment per se was able to enhance TBA-RS levels. Finally, nitric oxide production was not altered by Orn and Hcit alone or in combination with hyperammonemia. Our data indicate that the major metabolites accumulating in hyperornithinemia-hyperammonemia-homocitrullinuria syndrome provoke lipid and protein oxidative damage and a reduction of the antioxidant defenses in the brain. Therefore, it is presumed that oxidative stress may represent a relevant pathomechanism involved in the brain damage found in patients affected by this disease. 相似文献
43.
44.
Cécile Le Page Véronique Ouellet Michael C J Quinn Patricia N Tonin Diane M Provencher Anne-Marie Mes-Masson 《Cancer epidemiology, biomarkers & prevention》2008,17(4):913-920
This study aims to identify reliable prognosis markers to predict patient outcome at surgery in high-grade serous epithelial ovarian cancer by a real-time quantitative PCR (RT-q-PCR)-based test. Seventeen tissue samples from serous epithelial ovarian cancer patients were screened by DNA microarray to identify genes differentially expressed between tumors from patients who relapsed within 18 months and tumors from patients showing no relapse or relapsed after 24 months after initial diagnosis. RNA expression of a subset of genes was validated by RT-q-PCR in the initial set of 17 samples. From these results, a refined list was selected and tested in independent samples from 41 serous. Expression was associated with time to relapse and clinical variables. Microarray analysis identified a profile of 34 differentially expressed genes. RT-q-PCR validated the expression profile of a subset of seven genes in the initial set of patients. Differential gene expression was also validated in an independent set of patients. Low BTF4 or GCS expression was strongly associated with poor outcome in Kaplan-Meier analysis (P < 0.05, log-rank test) and Cox univariate as well as in multivariate analyses with a higher hazard ratio than clinical variables, such as residual disease, age, stage, and grade. 相似文献
45.
Abstract
Background:
Patients with bowel injuries resulting from blunt
abdominal trauma show no reliable clinical or radiologic signs
on initial examination. The mechanism of injury is the only
element of some diagnostic value. Intestinal injury may be
evaluated by ultrasonography (US), plain abdominal radiographs,
computed tomography (CT), and diagnostic laparoscopy. This paper
is a retrospective study of diagnostic procedures used in 45
consecutive patients with bowel injuries who presented at our
center between October 1996 and December 2001.
Patients and
Methods:
Of 45 patients (mean age 40 years), nine suffered isolated
bowel injuries and 36 presented with concomitant injuries. The
mechanism of trauma was traffic accident in 30 of 45 patients
(in 16 of these 30 patients compression by a seat belt), strong
blow to the abdomen in eight, fall from a height in five, and
other causes in two patients. US was done in 43 of 45 patients,
plain abdominal radiographs in 22, CT in six, peritoneal lavage
in one, and diagnostic laparoscopy in one.
Results:
37 of 43 patients were evaluated by US immediately upon
arrival; in four patients there was a delay in diagnosis of 1
day, and in two patients a delay of several days. At initial
sonography, free intraperitoneal fluid was identified in 32 of
the 43 patients; in most of them (n = 15) the amount of free
fluid was rather small. Free fluid was absent in eleven of 43
patients; yet seven of these eleven patients demonstrated free
fluid upon repeat examination.In nine of 32 patients, an increased amount of free fluid
was identified upon repeat examination. Two of 43 patients,
evaluated 3 and 9 days after arrival, respectively, showed dense
intraperitoneal fluid, suggestive of peritonitis. US identified
intestinal injuries in 14 of 43 patients; in all of them, the
diagnosis was established upon repeat examination or delayed
initial examination. Radiographs were performed in 22 of 45
patients (18 of them suffering perforation) and verified the
pneumoperitoneum in nine of 18 patients with perforation. CT
scanning identified intestinal injury in four of six patients.
17 of 45 patients were operated immediately in the Surgical
Emergency Unit, 15 patients in the first 24 h, eight patients 2
days after admission, and five patients > 2 days (max. 9
days) after admission. In our series of 45 patients, there were
four deaths, and only two (4.4%) were associated with bowel
injury.
Conclusion:
In patients presenting with a typical mechanism of trauma
and an abdominal bruise, plain radiographs should be taken in
addition to initial US to identify the presence of free air. In
patients with negative radiologic and US findings and in those
demonstrating a small quantity of free fluid, US scanning should
be repeated soon after the initial evaluation and, if necessary,
a CT scan should be taken. The use of laparoscopy is indicated
in unclear cases. According to our experience, a judicious and
timely decision for laparotomy can only be based on the
combination of the mechanism of injury, clinical picture, and
results of properly planned diagnostic tests. 相似文献
46.
Jean-Christophe Cassel Theresa Schweizer Anelise Lazaris Rainer Kn?rle Anja Birthelmer Ute G?dtel-Armbrust Ulrich F?rstermann Rolf Jackisch 《European neuropsychopharmacology》2005,15(2):163-175
Aging is associated with altered neurotransmitter function in the brain. In this study, we measured release parameters for acetylcholine (ACh), norepinephrine and serotonin in the frontoparietal cortex of young and aged rats. We also determined cortical amino acid concentrations and nitric oxide (NO) synthase function. Prior to sacrifice, the rats had been tested for Morris water-maze performance. In aged, compared with young rats, we observed a reduction in both uptake of choline and acetylcholine release. Serotonin release and L-arginine concentrations (a precursor of NO) showed an aging-related increase; however, L-citrulline/L-arginine ratios were decreased in aged rats. Moreover, while most age-related changes in transmitter release or neurochemical markers were not related to the learning performance, L-arginine concentrations were positively correlated to cognitive deficits. NO synthase concentrations were not affected by aging. It is suggested that events related to L-arginine-to-L-citrulline/NO metabolism in the frontoparietal cortex may take part in age-related cognitive deficits. 相似文献
47.
Regulation of penicillin-binding protein activity: description of a methicillin-inducible penicillin-binding protein in Staphylococcus aureus 总被引:10,自引:26,他引:10 下载免费PDF全文
The penicillin-binding proteins (PBPs) of two methicillin-resistant strains of Staphylococcus aureus (R2 and R1) were analyzed in cells grown in the absence and in the presence of methicillin. Under the former condition, strain R2 showed the typical PBP pattern of beta-lactam-susceptible strains, while strain R1 showed a markedly increased amount of PBP-3. Under the latter condition, on the other hand, a novel PBP (PBP-2a) located between PBP-2 and -3 was detected in strain R2, while strain R1 appeared to synthesize an even greater amount of PBP-3, in respect to untreated cells. Both R2 PBP-2a and R1 PBP-3 showed a very low affinity for methicillin, which was consistent with the MICs for the respective strains. 相似文献
48.
Effect of 180‐Day Water Storage on Bonding Effectiveness of Self‐Adhesive Systems to Occlusal and Proximal Dentin 下载免费PDF全文
49.
Lithium modulates the production of peripheral and cerebral cytokines in an animal model of mania induced by dextroamphetamine 下载免费PDF全文
50.
André Bortolini Silveira Angelo Brunelli Albertoni Laranjeira Gisele Olinto Libanio Rodrigues Paulo César Leal Bruno António Cardoso Jo?o Taborda Barata Rosendo Augusto Yunes Nilson Ivo Tonin Zanchin Sílvia Regina Brandalise José Andrés Yunes 《Oncotarget》2015,6(15):13105-13118
The PI3K pathway is frequently hyperactivated in primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Activation of the PI3K pathway has been suggested as one mechanism of glucocorticoid resistance in T-ALL, and patients harboring mutations in the PI3K negative regulator PTEN may be at increased risk of induction failure and relapse. By gene expression microarray analysis of T-ALL cells treated with the PI3K inhibitor AS605240, we identified Myc as a prominent downstream target of the PI3K pathway. A significant association was found between the AS605240 gene expression signature and that of glucocorticoid resistance and relapse in T-ALL. AS605240 showed anti-leukemic activity and strong synergism with glucocorticoids both in vitro and in a NOD/SCID xenograft model of T-ALL. In contrast, PI3K inhibition showed antagonism with methotrexate and daunorubicin, drugs that preferentially target dividing cells. This antagonistic interaction, however, could be circumvented by the use of correct drug scheduling schemes. Our data indicate the potential benefits and difficulties for the incorporation of PI3K inhibitors in T-ALL therapy. 相似文献