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971.
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. To explore the genetic origins of this cancer, we used whole-exome sequencing and gene copy number analyses to study 32 primary tumors. Tumors from patients with a history of tobacco use had more mutations than did tumors from patients who did not use tobacco, and tumors that were negative for human papillomavirus (HPV) had more mutations than did HPV-positive tumors. Six of the genes that were mutated in multiple tumors were assessed in up to 88 additional HNSCCs. In addition to previously described mutations in TP53, CDKN2A, PIK3CA, and HRAS, we identified mutations in FBXW7 and NOTCH1. Nearly 40% of the 28 mutations identified in NOTCH1 were predicted to truncate the gene product, suggesting that NOTCH1 may function as a tumor suppressor gene rather than an oncogene in this tumor type.  相似文献   
972.
973.
The objective of this study was to compare the safety of all modified live virus vaccines commercially available in Europe against Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) under the same experimental conditions. For this purpose, one hundred and twenty three-week-old piglets, divided into five groups, were used. On day 0 of the experiment, nine pigs per group were removed and the remaining fifteen were vaccinated with the commercial vaccines Ingelvac PRRS MLV, Amervac PRRS, Pyrsvac-183 and Porcilis PRRS by the IM route or were mock vaccinated and used as controls. On day 3, the nine unvaccinated pigs were re-introduced into their respective groups and served as sentinel pigs. Clinical signs were recorded daily and lung lesions were determined on days 7, 14 and 21, when 5 vaccinated pigs per group were euthanized. Blood samples and swabs were taken every three days and different organs were collected at necropsy to determine the presence of PRRSV. None of the vaccines studied caused detectable clinical signs in vaccinated pigs although lung lesions were found. Altogether, these results indicate that all vaccines can be considered clinically safe. However, some differences were found in virological parameters. Thus, neither Pyrsvac-183 nor Porcilis PRRS could be detected in porcine alveolar macrophage (PAM) cultures or in lung sections used to determine PRRSV by immunohistochemistry, indicating that these viruses might have lost their ability to replicate in PAM. This inability to replicate in PAM might be related to the lower transmission rate and the delay in the onset of viremia observed in these groups  相似文献   
974.
975.
Identification and classification of classical swine fever virus (CSFV) on the basis of nucleotide sequencing and phylogenetic analysis have become an important tool to study the epidemiology and to control CSF disease. According to phylogenetic analyses of short sequences from the 5′nontranslated region (150 nt) and the E2 (190 nt), most CSFV isolates from South and Central America have been assorted to the subgenotypes 1.1 and 1.3, while CSFV isolates from Cuba have been allocated to subgenotype 1.2. Here we demonstrate that determination and comparison of full-length E2 sequences as well as of the sequences encoding for Npro, C, Erns, E1 and E2 (3361 nt) do not support segregation of Cuban CSFV isolates to subgenotype 1.2. In fact, our analysis revealed that the Cuban isolates are more divergent from other so far known CSFV subgenotype 1 isolates and form a novel separate subgenotype that is proposed to be designated subgenotype 1.4.  相似文献   
976.
A 10-month-old intact male cat with a clinical history of a large mass in the left perineal region was submitted to the surgery department. The mass had reportedly been present as a small swelling after birth. Cytological evaluation using a fine-needle aspirate showed eosinophilic keratinaceous debris, and was not convincing for the definitive diagnosis. Complete surgical excision was performed. Postoperative function and aesthetics were excellent. Based on gross and histological features the definitive diagnosis of the tumor was mature teratoma with ectodermal and endodermal components. After a follow-up period of 4 months, no signs of recurrence were evident. Surgical excision of the teratoma in our case was considered curative. A perineal location has not been previously reported in the cat and should be considered a rare condition in this species.  相似文献   
977.

Background

Methicillin-resistant staphylococci (MRS) are increasingly being isolated in bovine mastitis. The aim of our study was to evaluate the occurrence of MRS in Finnish mastitis milk samples and characterize the MRS isolates using molecular methods.

Results

Methicillin-resistant S. aureus (MRSA) was a rare finding in bovine mastitis in Finland. Only two out of 135 (1.5%) S. aureus isolates were positive for mec genes. One of these carried mecA and was of spa type t172, SCCmec type IV and ST375, and the other harboured mecC, being spa type t3256, and ST130. MRSA ST375 is common among human MRSA isolates in Finland, but this is the first report in the country of bovine mecC MRSA. In coagulase-negative staphylococci (CoNS) originating from bovine mastitis, methicillin resistance was more common. In the two CoNS collections studied, 5.2% (17/324) and 1.8% (2/110) of the isolates were mecA positive. Eighteen of these were methicillin-resistant S. epidermidis (MRSE), which were divided into 6 separate PFGE clusters. One pulsotype was detected in different parts of the country, indicating clonal spread. Most MRSE (13/18) were of SCCmec type IV, one was of type V and four were non-typeable. Comparison with a human staphylococcal database indicated that bovine MRSE strains were not closely related to human MRSE isolates.

Conclusions

The occurrence of MRS, especially MRSA, in bovine mastitis in Finland was low. Most methicillin-resistant bovine CoNS are MRSE, and we found evidence of a bovine MRSE strain that may spread clonally. This is the first report of a Finnish bovine isolate of MRSAmecC ST130. The study provides a baseline for further MRS monitoring.  相似文献   
978.
Key concepts and research priorities for landscape sustainability   总被引:2,自引:2,他引:0  
  相似文献   
979.
Summary

During an ongoing effort to recover and preserve local germplasm, 14 accessions of indigenous minor grapevine (Vitis vinifera L.) cultivars from the Umbria Region, Central Italy, were chosen because they had been neglected and were threatened with extinction. Their phenotypic and genetic characteristics were evaluated through an ampelographic study of their shoots, mature leaves, bunches, and berries and by genomic analysis using an international set of nine microsatellite (simple sequence repeat; SSR) markers (VVS2, VVMD5, VVMD7, VVMD27, VrZAG62, VrZAG79, VVMD25, VVMD28, and VVMD32). Comparisons of the SSR profiles of all 14 accessions with grapevine accessions in several databases permitted the identification of unique genotypes, as well as possible synonyms. Information on these older, neglected cultivars will help to reduce the genetic erosion of grapevine germplasm, improve conservation and possible recovery, and assist in the future production of new, distinctive wines.  相似文献   
980.
Rice bran is a rich source of valuable nutrients and has potential for high-value applications. Endogenous lipases catalyze the hydrolysis of rice bran oil to free fatty acids, which initiates lipid oxidation. The evaluation of the success of rice bran stabilization processes in terms of the degree of lipid oxidation and shelf-life has so far relied on the measurement of free fatty acid content over a storage period of 3–6 months. In the present study, a photometric and a titrimetric pH-stat method for direct lipase activity measurement immediately after debranning were adapted to rice bran. The photometric method was further applied to determine rice bran lipase/esterase inactivation kinetics, which are useful to optimize stabilization treatments in order to prevent overprocessing and retain maximum level of nutrients. Rice bran was heat-treated in a specialized, hermetically sealable reactor at controlled holding times (5–40 min), temperatures (70–145 °C) and moisture contents (10–20%). Temperature dependency of the lipase/esterase inactivation rate could be described by the Arrhenius equation. Empirical findings on the importance of moisture content for effective rice bran stabilization could be quantified. Furthermore, the results demonstrate the great potential of the method to predict the shelf-life of stabilized rice bran without time-consuming storage tests.  相似文献   
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