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Altosid (I) was found to have an ED50 of 0.026 μg/g in T. molitor and 5.0 μg/g in O. fasciatus. The juvenilizing activity of I in T. molitor was increased by co-treatment with piperonyl butoxide (PB) and triorthocresyl phosphate (TOCP). The activity of I in O. fasciatus, was considerably decreased by PB and TOCP indicating the blocking of an activation reaction. The presumptive metabolities of I, isopropyl 11-hydroxy-3,7,11-trimethyldodeca-2,4-dienoate, (II), 11-methoxy-3,7,11-trimethyldodeca-2,4-dienoic acid (III), and 11-hydroxy-3,7,11-trimethyldodeca-2,4-dienoic acid (IV) were tested for juvenilizing activity in O. fasciatus and II was found to be four times more active than I. IV was more active than III but less active than I. Co-treatment of II with PB or TOCP did not decrease activity, indicating that II is a true activation product. Uptake studies with 14C-I showed that the difference in activity between the two insects was not due to differences in uptake. Forty-eight hours after treatment 30% of I was lost from the cuticle by evaporation. Metabolic studies showed that PB inhibited the formation of II and TOCP inhibited the formation of III in T. molitor while in O. fasciatus both synergists inhibited the formation of II.  相似文献   
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The effects of fenoxycarb, an insect growth regulator, on predatory anthocorids, were tested in comparison with the broad-spectrum insecticide deltamethrin, in pear orchard trials. The results confirmed the effectiveness of fenoxycarb against pear sucker, Cacop- sylla pyricola and revealed no damaging effects on larval or adult anthocorids (mainly Anthocoris nemoralis). Deltamethrin reduced numbers of both C. pyricola and anthocorids, allowing a resurgence of C. pyricola later in the season. Fenoxycarb is shown to be suitable for use in integrated pest management programmes in pear.  相似文献   
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Introduction:  Splenic lesions are a common finding in veterinary medicine and typically 1/2 to 2/3 of these lesions are malignant. Due to the limited accuracy of ultrasound, unnecessary exploratory surgeries/biopsies may be performed for benign lesions and treatment may be delayed for malignant ones. Splenic lesions are rare in people. MR imaging, with its inherently high soft tissue contrast, is efficacious in imaging the human spleen. We have previously demonstrated the efficacy of MRI to differentiate canine hepatic lesions. In that study 8 splenic lesions were all accurately characterized. This current study represents a further evaluation of splenic lesions.
Methods:  In this prospective study, 27 dogs with splenic lesions were accrued. Histopathological/cytological confirmation of lesions occurred either before or shortly after imaging. MRI clinicians were blinded to histopathology results. MR (General Electric, 1.5 Tesla) images using a variety of sequences were obtained before and after intravenous administration of gadolinium.
Results:  32 lesions (9 malignant, 23 benign) were evaluated in 27 dogs. Lesions were confirmed via histopathology (n = 20) or cytology (n = 12). Benign lesions included, EMH (n = 7), hematoma/hemorrhage (n = 5), lymphoid hyperplasia (n = 9), and hemangioma (n = 2). Malignant lesions included anaplastic sarcoma (n = 3), malignant histiocytosis (n = 2), hemangiosarcoma (n = 2), plasma cell tumor (n = 1) and adenocarcinoma (n = 1). The overall accuracy in differentiating benign from malignant lesions was 88%(29/32 lesions). The overall sensitivity and specificity were 100%(95% CI, 66–100) and 87%(95% CI 66–97).
Conclusions:  Based upon these results, MRI is both sensitive and specific in distinguishing between malignant and benign splenic lesions.  相似文献   
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CASE DESCRIPTION-5 Dogs, 1 goat, and 1 horse underwent percutaneous endovascular retrieval of intravascular foreign bodies between 2002 and 2007. CLINICAL FINDINGS-Foreign bodies were IV catheters in 4 dogs, the horse, and the goat and a piece of a balloon valvuloplasty catheter in 1 dog. Location of the foreign bodies included the main pulmonary artery (1 dog), a branch of a pulmonary artery (4 dogs), the right ventricle (the goat), and a jugular vein (the horse). TREATMENT AND OUTCOME-The procedure of percutaneous endovascular retrieval of the foreign body was easy to perform in all instances. One dog was euthanized 41 days after retrieval because of worsening of another disease process, and 1 dog had abnormal neurologic signs secondary to a brain mass. All other animals were clinically normal during the follow-up period (follow-up duration, 3 to 57 months). None of the animals developed long-term complications secondary to the foreign body retrieval procedure. CLINICAL RELEVANCE-Intravascular foreign bodies that result from catheters or devices used during minimally invasive techniques are rare but may cause substantial morbidity. Percutaneous endovascular retrieval of intravascular foreign bodies was easily and safely performed in the 7 animals reported here. Use of percutaneous endovascular retrieval techniques should be considered for treatment of animals with intravascular foreign bodies because morbidity can be substantially decreased; however, proper selection of patients for the procedure is necessary.  相似文献   
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Digestibility and feeding trials for 10 and 90 days were conducted using 25 yearling Farta rams with a mean body weight (BW) of 16.8 ± 0.17 kg (mean ± SD) to study the effects of supplementation with sole or mixtures of noug seed meal (NSM) and wheat bran (WB) on feed intake, digestibility and BW change in Farta sheep fed hay. The experimental design was a randomized complete block design. The sheep were arranged in five blocks based on initial BW, and the five treatments were assigned randomly to each animal in a block. The five treatments comprised of ad libitum hay (control, T1) and ad libitum hay plus daily supplementation of 300 g dry matter (DM) sole WB (T2), 2WB:1NSM (T3), 1WB:2NSM (T4) and sole NSM (T5). Supplementation increased total DM (P < 0.01) and crude protein (CP) (P < 0.001) intake and promoted daily BW gain (P < 0.001). Non- supplemented sheep consumed more (P < 0.01) hay DM compared to the supplemented treatments, except T2. Among supplemented sheep, T5 had higher (P < 0.001) CP intake than the other treatments. Supplementation improved (P < 0.001) the digestibility of CP. Lack of statistical differences in daily BW gain between the different supplements used in this study suggests that sheep producers can use the different feed supplements considered in this study depending on their availability in the order of T4, T5, T3 and T2, respectively.  相似文献   
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With the current water shortage in East Africa improving crop water use is vital especially in the arid and semi-arid regions of Ethiopia. To understand the response of barley to water and to simulate the biomass and grain yield of barley under various water inputs and planting dates, we tested the FAO AquaCrop model versions 3.0 using independent data sets during the cropping seasons of 2006, 2008 and 2009 at Mekelle site in northern Ethiopia. We found that the model is valid to simulate the barley biomass and grain yield under various planting dates in the study site. AquaCrop model can be used in the evaluation of optimal planting time. Out of the tested planting dates, planting on July 4 (early sowing) was found to maximize barley biomass, grain and water use efficiency. The model can also be used in the evaluation of irrigation strategies. Barley showed slightly lower performance under mild water stress condition compared to full irrigation condition. However, the model has indicated the possibility of obtaining more biomass and grain yield from a relatively larger barley field under (deficit irrigation) mild stress condition.  相似文献   
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