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81.
82.
Honey mesquite (Prosopis glandulosa) is distributed across a large portion of the southwestern United States. Ingestion of young leaves, pods, or beans can cause toxicosis in cattle and goats if they comprise a substantial portion of their diet. Goats, as browsers, are most likely to develolp mesquite toxicosis. Sheep appear to be more resistant to the plant's toxic effects. Consistent clinical signs include weight loss, ptyalism, mandibular tremors, tongue protrusion, and dysphagia. Diagnosis of mesquite toxicosis is largely made on the basis of history and clinical signs with exclusion of appropriate differentials. Laboratory findings are nonspecific but may reveal a mild anemia and hypoglycemia. Postmortem findings suggestive of mesquite toxicosis are limited to fine vacuolation of neurons in the trigeminal motor nucleus. Treatment consists of an alternative diet and supportive care. The disease is treatable in cattle and sheep but has a high case fatality rate in goats.  相似文献   
83.
Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a major problem, causing severe and intractable infections worldwide. MRSA is resistant to all beta-lactam antibiotics, and alternative treatments are limited. A very limited number of new antibiotics have been discovered over the last half-century, novel agents for the treatment of MRSA infections are urgently needed. Marinopyrrole A was reported to show antibiotic activity against MRSA in 2008. After we reported the first total synthesis of (±)-marinopyrrole A, we designed and synthesized a series of marinopyrrole derivatives. Our structure activity relationship (SAR) studies of these novel derivatives against a panel of Gram-positive pathogens in antibacterial assays have revealed that a para-trifluoromethyl analog (33) of marinopyrrole A is ≥63-, 8-, and 4-fold more potent than vancomycin against methicillin-resistant Staphylococcus epidermidis (MRSE), methicillin-susceptible Staphylococcus aureus (MSSA) and MRSA, respectively. The results provide valuable information in the search for new-generation antibiotics.  相似文献   
84.
A proprietary Flavonol Polymer Technology (FPT), designed by AgroLiquid, is an agent for encapsulating different chemistries on the polymer by impregnation to provide extended release of nutrients and optimize yield. Based on FPT, FPT-Product (Pro-Germinator®) a 9-24-3 (% N, % P2O5, and % K2O w/w) manufactured to slow the phosphorus release process in soil and extends its usability by the plant. Phosphorus release was evaluated using micro-lysimeters installed in soil and used as a tool for the collection of the plant-usable phosphorus dissolved in the soil solution. A rate of 22 kg of P2O5/hectare of liquid formulations was banded in-furrow with four phosphorus liquid fertilizer treatments: (1) orthophosphate (9-18-9), (2) ammonium polyphosphate (10-34-0), (3) FPT-Product (9-24-3), and (4) a control. In-field measurements were collected at 20–60 days after the application for two successive years (2015 and 2016). In both years, averages of measured dissolved phosphorus in the soil solution and exchangeable soil phosphorus at 10-cm soil depth, 20–60 days after planting reported higher values in the FPT-Product treatments while lower values were measured in the other treatments. The results proved that the FPT extended the release mechanism for phosphorus in the FPT-Product at 10 cm depth in the soil, and rendered phosphorus in both the soil and the solution to be used by plants for an extended period after corn planting.  相似文献   
85.
The nutritional quality of 13 commercial fish meals (10 from pollock, two from salmon, and one from cod) made from by-products of the Alaska fish processing industry was determined in diets for the marine fish Pacific threadfin Polydactylus sexfilis . Pelleted feeds were manufactured containing these meals as complete replacement of a low-temperature processed Norwegian fish meal (control). These feeds were fed to triplicate tanks of fish at the facilities of the Oceanic Institute, Hawaii for a period of 9 wk. At the end of the trial, the final weight, feed efficiency, protein efficiency ratio and survival data were subjected to ANOVA procedures. The performance parameters of the fish fed the white fish meals (pollock and cod) were not significantly different from the control. Of the two salmon meals, one promoted good growth and efficiency and one did not. It is concluded that the nutritional quality of Alaska white (pollock and cod) fish meals is equivalent to that of the low-temperature Norwegian fish meal and are of suitable quality for inclusion in commercial feeds for Pacific threadfin.  相似文献   
86.
87.
Increased susceptibility to intracellular pathogens in HIV-infected individuals and FIV-infected cats is attributed to a defective T-helper 1 (Th1) immune response. However, little is known about specific cytokine responses to secondary pathogens. To address this question, control and FIV-infected cats were challenged with Toxoplasma gondii, and lymph node cells analyzed for cytokine mRNA expression. Twenty-four weeks post-FIV infection, prior to T. gondii challenge, IL2 and IL12 mRNAs were depressed, whereas IL10 and IFNgamma mRNAs were increased in CD4+ and CD8+ subsets. Following T. gondii challenge, control cats showed increased expression of IL2, IFNgamma, IL10, IL12, and IL6 mRNAs. In contrast, IL2, IL6, IFNgamma, and IL12 mRNAs were suppressed in FIV-T. gondii co-infected cats, whereas IL10 remained at the high prechallenge levels. IFNgamma and IL10 mRNAs were produced by both CD4+ and CD8+ cells in FIV-T. gondii cats. Elevated IL10 may suppress a Th1 cytokine response to T. gondii challenge.  相似文献   
88.
Plants and their arbuscular mycorrhizal fungal symbionts interact in complex underground networks involving multiple partners. This increases the potential for exploitation and defection by individuals, raising the question of how partners maintain a fair, two-way transfer of resources. We manipulated cooperation in plants and fungal partners to show that plants can detect, discriminate, and reward the best fungal partners with more carbohydrates. In turn, their fungal partners enforce cooperation by increasing nutrient transfer only to those roots providing more carbohydrates. On the basis of these observations we conclude that, unlike many other mutualisms, the symbiont cannot be "enslaved." Rather, the mutualism is evolutionarily stable because control is bidirectional, and partners offering the best rate of exchange are rewarded.  相似文献   
89.
90.
Despite recent strides in the synthesis of elaborate nanometer-scale molecular hosts, the internal structure of these self-assembled cages remains ill characterized. We used fluorescent probe molecules, pyrene butyric acid (PBA), as guests in C-hexylpyrogallol[4]arene capsules to relay information about the chemical environment on the interior of the assemblies. Spectroscopic and single-crystal x-ray diffraction studies show that, in both solution and the solid state, the host can encapsulate two PBA guests and keep them well separated through specific interactions with the capsule walls.  相似文献   
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