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151.
Pancreatic triglyceride lipase is involved in the virulence of the brown planthopper to rice plants 下载免费PDF全文
The brown planthopper (BPH), Nilaparvata lugens, an important rice insect pest, can enhance its virulence to BPH-resistant rice within as short a span as several generations. Here, we cloned a pancreatic triglyceride lipase (PTL) gene (NlPTL) in N. lugens, and found that its mRNA level was higher in the high virulence population (fed on variety Rathu Heenati, P-RH) than in the low virulence population (fed on variety Taichung Native 1, P-TN1). Knocking down NlPTL caused BPH individuals to spend more time in non-penetration and the pathway phases and less time feeding on the phloem of rice plants; these changes consequently decreased food intake, lipid content, survival rate, and fecundity in the insects. These findings reveal for the first time that PTL in BPH is involved in its virulence to rice plants. 相似文献
152.
K Halse 《Acta veterinaria Scandinavica》1984,25(2):213-228
Urinary excretion rates for Ca, Mg and P were compared to simultaneous measurements of the same elements in blood plasma of cows recovering from moderate hypocalcaemia post partum and in 1 animal during recovery from hypocalcaemia induced by fasting.The renal conservation of Mg was found to be increased during the hypocalcaemia, theoretical tubular reabsorption rates being correlated to plasma Ca with r = –0.7, P < 0.001. The relationship was observed in the plasma Ca range from about 2.0 to 2.6 mmol/1.The findings may explain the occurrence of hypermagnesaemia in hypocalcaemic cows and the delay in the development of hypo-magnesaemia seen in cows with fasting-induced hypocalcaemia. 相似文献
153.
Andreia S. Fernandes Catarina Oliveira Rui L. Reis Albino Martins Tiago H. Silva 《Marine drugs》2022,20(11)
Despite its low prevalence, pancreatic cancer (PC) is one of the deadliest, typically characterised as silent in early stages and with a dramatically poor prognosis when in its advanced stages, commonly associated with a high degree of metastasis. Many efforts have been made in pursuing innovative therapeutical approaches, from the search for new cytotoxic drugs and other bioactive compounds, to the development of more targeted approaches, including improved drug delivery devices. Marine biotechnology has been contributing to this quest by providing new chemical leads and materials originating from different organisms. In this review, marine biodiscovery for PC is addressed, particularly regarding marine invertebrates (namely sponges, molluscs, and bryozoans), seaweeds, fungi, and bacteria. In addition, the development of biomaterials based on marine-originating compounds, particularly chitosan, fucoidan, and alginate, for the production of advanced cancer therapies, is also discussed. The key role that drug delivery can play in new cancer treatments is highlighted, as therapeutical outcomes need to be improved to give further hope to patients. 相似文献
154.
Dual-phase computed tomographic angiography in three dogs with pancreatic insulinoma. 总被引:2,自引:2,他引:0
This article describes the findings in three dogs with histopathologically confirmed pancreatic insulinoma using dual-phase computed tomographic angiography (CTA). In all three dogs, dual-phase CTA findings identified lesions not seen on ultrasonography, including the actual identification of the primary pancreatic neoplasm in two dogs. CTA findings were in agreement with the surgical and histopathological findings. In two dogs, the insulinomas were found to have a strong enhancement during the arterial phase of the study but not at the other phases, which stresses the importance of dual-phase computed tomography for the diagnosis of this type of pancreatic neoplasia, in agreement with current knowledge in humans. 相似文献
155.
A. Péres C. L. Cahu J. L. Zambonino Infante M. M. Le Gall P. Quazuguel 《Fish physiology and biochemistry》1996,15(3):237-242
Sea bass (Dicentrarchus labrax) larvae were fed from day 15 to day 35 with 4 isoenergetic formulated diets that varied in protein (30, 40, 50, 60%) and carbohydrate (37, 27, 17, 7%) content. The diets were designated as P30, P40, P50 and P60, respectively. Best growth and survival were noted for P50 larvae. Poor growth and survival were observed for P30 larvae. The specific activity of amylase increased in direct relation to the dietary carbohydrate level from day 18 onwards. This increase was the result of extensive amylase synthesis. Trypsin activity was positively correlated with dietary protein level only at day 35. This study shows that the mechanisms involved in amylase regulation are efficient in very young sea bass larvae, while those related to trypsin appear later in ontogeny and thus suggests an age-dependent regulation of enzyme synthesis. 相似文献
156.
A 7-year-old neutered, male, fitch ferret presented for weight loss, decreased appetite, reduced bowel movements, and occasional bruxism. Physical examination confirmed weight loss of 340 g over the preceding 7 months. Abnormal clinicopathologic results included lymphopenia, monocytosis, increased alkaline phosphatase, increased alanine transferase, markedly increased total bilirubin, and hypocalcemia. Plasma glucose was normal. After a discussion of diagnostic and therapeutic options, the owner decided to humanely euthanize the patient and consented to cosmetic necropsy. Microscopic examination of submitted tissues revealed an unencapsulated, infiltrative neoplasm that effaced the pancreatic architecture and metastasized to several other organs, including the lung, liver, and jejunum. Based on the cellular morphology, presence of distinctive rosettes, immunonegativity for insulin, and widespread metastasis, the disease diagnosis was exocrine pancreatic adenocarcinoma. 相似文献
157.
158.
A 7-year-old male neutered domestic shorthair cat was referred for worsening gastrointestinal and haematologic abnormalities. Physical status deteriorated further despite intravenous crystalloids, blood transfusion and nutritional support. Cardiorespiratory signs developed and the cat died suddenly while straining to defaecate. Diffuse thrombosis, pulmonary thromboembolism, metastatic pancreatic carcinoma and histologic evidence of cardiomyopathy were present at necropsy. This is the first reported case of feline pulmonary thromboembolism associated with defaecation syncope. Predisposing factors for thrombotic disease in this case and aspects of human defaecation syncope are discussed. The risk of clot dislodgement by the Valsalva manoeuvre in patients with a thrombotic tendency is highlighted. 相似文献
159.
SILKE HECHT DOMINIQUE G. PENNINCK JOHN H. KEATING 《Veterinary radiology & ultrasound》2007,48(1):45-50
Pancreatic neoplasia in cats is rare and associated with a poor prognosis, but pancreatic nodular hyperplasia is a common incidental finding. The purpose of this study was to describe radiographic and ultrasonographic findings in cats with pancreatic neoplasia or nodular hyperplasia. Fourteen cats (age 3-18 years) were diagnosed with malignant pancreatic tumors: carcinoma/adenocarcinoma (n = 11), lymphoma (n = 1), squamous cell carcinoma (n = 1), and lymphangiosarcoma (n = 1). The most common radiographic findings were an abdominal mass or mass effect (6/6) and lack of serosal margin detail (4/6). On ultrasound, the most common finding was a focal pancreatic mass or nodule, with a size range from 0.4 cm to more than 7.0 cm (8/14). Lymphadenopathy (7/14) and abdominal effusion (7/14) were frequently seen. Five cats (age 10-16 years) with adenomatous/nodular hyperplasia had an abdominal mass or mass effect as the most common radiographic finding (3/3). On ultrasound, all cats had multiple hypoechoic nodules between 0.3 and 1.0 cm associated with the pancreas. Other common findings were pancreatic thickening (2/5), lymphadenopathy (2/5), and abdominal effusion (2/5). The only imaging finding unique to malignant pancreatic tumors was the presence of a single pancreatic nodule or mass exceeding 2cm in at least one dimension (4/14). Although there was a tendency for neoplastic lesions to manifest as single larger lesions and for nodular hyperplasia to manifest as multiple smaller lesions, there was overlap of the imaging findings in both entities. Radiographs and ultrasound can complement but not replace cytology and histopathology in the diagnosis of feline pancreatic neoplasia. 相似文献
160.
AIM: To construct a eukaryotic expression vector containing pancreatic duodenal homebox-1 (PDX-1) and to elevate the expression efficiency of exogenous gene in rat bone marrow mesenchymal stem cells (MSCs). METHODS: Recombinant vector containing PDX-1 was constructed. Flow cytometry was used to identify the cell cycle of bone marrow mesenchymal stem cells (MSCs) cultured in vitro. Recombinant vector containing PDX-1 was transfected into bone marrow MSCs using superfect in medium. After being selected by G418, RT-PCR and Western blotting were used to investigate the expression of PDX-1 in MSCs. RESULTS: Restricted enzyme analysis and sequencing showed that PDX-1 gene segment was consistent with that in GenBank. Flow cytometry showed that there were about 85.9% cells at the cell cycle of G0/G1. The whole cells transfected emitted green fluorescence under flow cytometry. The efficiency of transfection was above 40%. RT-PCR and Western blotting demonstrated that there was expression of PDX-1 in transfected bone marrow MSCs. CONCLUSION: Recombinant vector containing PDX-1 was constructed successfully. Superfect mediated expression of exogenous gene in bone marrow MSCs in a high efficiency, and bone marrow MSCs containing exogenous gene are an ideal cells for gene therapy. 相似文献