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81.
82.
A novel product (SQ12) for subcutaneous (SQ) injectable delivery of oxytetracycline (OTC) has been developed for use in livestock. SQ12 employs microfluidic spheres encasing OTC crystals, which allows for longer release of the OTC compared with other injectable antibiotics. The objectives of the study were to determine serum and tissue levels of SQ12 in turkey breeder hens to 14 days postinjection and to evaluate effects of SQ12 on reproductive status. Thirty photostimulated hens were housed in litter floor pens and provided with 14.5 hr of light per day in a curtain-sided facility. Six hens served as untreated controls. Twelve hens per treatment group received SQ injections in the neck with SQ12 at 11.4 (L dose group) or 22.7 mg/kg (H dose group) to assess low and high doses, respectively. Serum samples were obtained from each hen at predose and 6, 12, 24, 48, 72, 96, 168, 240, and 336 hr postinjection. All hens were euthanatized at 14 and 15 days postinjection. One-half of the hens in each treatment group were sampled (liver, lung, kidneys, and breast muscle) for tissue residue levels of OTC. The control group had no detectable OTC in serum or tissues at any sample collection time. There were no detectable serum levels of OTC in either treatment group prior to injection. The average serum concentrations of the L and H dose groups showed similar depletion curves although the H dose group was 42% higher at maximum concentration than the L group. Average tissue concentration of OTC for all tissues sampled from the H dose group was twice that of the L dose group. All tissue levels were below the OTC residue tolerance limit. SQ12 provided an extended source of OTC in serum of turkey breeder hens with no effect on reproductive status. SQ12 may provide for a novel treatment of bacterial infection in turkey breeder hens with longer lasting serum levels compared with other single injectable OTC products.  相似文献   
83.
Sedimentary rocks at Eagle crater in Meridiani Planum are composed of fine-grained siliciclastic materials derived from weathering of basaltic rocks, sulfate minerals (including magnesium sulfate and jarosite) that constitute several tens of percent of the rock by weight, and hematite. Cross-stratification observed in rock outcrops indicates eolian and aqueous transport. Diagenetic features include hematite-rich concretions and crystal-mold vugs. We interpret the rocks to be a mixture of chemical and siliciclastic sediments with a complex diagenetic history. The environmental conditions that they record include episodic inundation by shallow surface water, evaporation, and desiccation. The geologic record at Meridiani Planum suggests that conditions were suitable for biological activity for a period of time in martian history.  相似文献   
84.
An acidic pectin methylesterase (PME) is responsible for the gelation of water extract from jelly fig (Ficus awkeotasang) achenes. A new, fast and efficient, method has been developed to purify this acidic PME. The method includes preparing jelly curd by traditional hand washing, extracting proteins from the curd, and separating PME by anion-exchanger. The purified PME exists as a monomer of 38 kDa determined by gel filtration, and exerts enzymatic activity over a broad pH range, particularly in acidic environments where most known PME enzymes from various species are inactivated. Chemical staining and enzymatic cleavage suggest that the jelly fig PME is an N-linked glycoprotein. Fluorophore-assisted carbohydrate electrophoresis reveals that the polysaccharide of this glycoprotein putatively consists of 22 hexoses including 16 mannose, 4 N-acetylglucosamine, and 2 galactose residues.  相似文献   
85.
The experiment was designed to investigate the dietary factors that might enhance or interfere with astaxanthin (Ax) absorption in salmon including potentially interfering factors such as certain carotenoids (zeaxanthin and lutein), plant sterols, fibre and enhancing compounds such as cholesterol and vitamin E. Two hundred and eighty‐eight salmon (778 ± 78 g) were reared in sea water under controlled conditions and fed practical experimental diets. The experimental diets were supplemented with 40 mg Ax kg?1, in addition to various dietary factors, including cholesterol (2%), vitamin E (450 IU kg?1), wheat bran (5%), lutein (40 mg kg?1), zeaxanthin (40 mg kg?1) and phytosterol (2%). After 26 days of feeding, blood was collected and plasma was separated to determine the plasma Ax concentration. Ax was not detected in the plasma of fish fed the non‐pigmented diet. Fish fed diet containing 2% cholesterol significantly improved Ax absorption, which was reflected in the higher Ax concentration in plasma of Atlantic salmon. Other supplements including vitamin E, wheat bran, lutein, zeaxanthin and phytosterols in diet had no significant effect on plasma Ax concentration . Fish fed diet containing 2% cholesterol significantly increased cholesterol concentration in fish plasma. Phytosterol had no benefit to lower cholesterol plasma level in fish fed 2% phytosterol‐supplemented diet.  相似文献   
86.
The needs of the modern system of integrated control, or pest management, are contrasted with those of the prevailing view that pest control is an individual responsibility. It is argued that a rational approach to pest management must be based on a knowledge of the scale on which it must be exercised. In the case of mobile insects the scale normally far exceeds the ecologically artificial boundaries represented by fields or private holdings. The argument is illustrated by the desert locust where numbers are reckoned in millions of millions and mobility in terms of hundreds and thousands of km., calling for international action, and the Tsetse fly where numbers are reckoned in less than 10 per ha. and mobility in terms of km. Experience in the control of paddy pests in Java is drawn on to show the contribution of synoptic survey to delimit the scale and time for appropriate action, followed by synchronous application of pesticides in achieving, through control of pests, yield increases in excess of what could be expected from small scale plot trials. The value of spraying at ultra-low volume rates is that it provides the means of achieving more or less synchronous application of pesticides on the scale demanded by the problem.  相似文献   
87.
A new antimicrobial ear cleanser was evaluated for the treatment of bacterial and yeast ear infection in dogs. Forty-five dogs with erythemato-ceruminous or purulent otitis externa were randomly allocated to two treatment groups: reference ear cleanser (Epiotic, Virbac) or test ear cleanser (Epiotic Advanced, Virbac). Ear cleansing was performed twice daily for 2 weeks, and no other treatment was allowed. By week 2, clinical (exudate quantity, erythema, stenosis, excoriation, and odor) and discomfort (pain, ear scratching, and head shaking) scores were significantly decreased (P < .0001 for all) and no microbial overgrowth could be detected in 25 (64.1%) and 32 (68.1%) ears treated with Epiotic and Epiotic Advanced, respectively. The new pH-balanced, propylene glycol-free test ear cleanser, which incorporates microbial adhesin-blocking carbohydrates, proved as effective as the reference acidic formula.  相似文献   
88.
Headspace components from rice and agar with (experimental) and without (control) inoculation with a Monascus spp. were investigated. Kinetics studies were carried out. Using rice as a substrate, 10 and 19 compounds were found for the control and the experimental groups, respectively, at day 14. Experimental group compounds were composed mainly of alcohols, ketones, and esters, whereas control group compounds were composed of aldehydes and ketones. With agar as a substrate, only five and three components were found in the control and experimental groups, respectively. Five alcohols, four esters, two ketones, and one furan with odor activity values (OAV) >1 dominated the overall flavor of the product. With liquid inoculation, the first six components with high OAVs were in the following order: 3-methyl-1-butanol (17) > ethanol (14) > ethyl acetate (10) > 2-methyl-1-propanol (15) > ethyl butanoate (11) > 3-methylbutyl acetate (13). Kinetic studies showed that most compounds reached their maximum concentrations at 10-12 days. Many compounds identified in the model red rice were reported in commercial red sufus, and several appeared to contribute solely by red rice.  相似文献   
89.
The porbeagle (Lamna nasus) is a large fast‐swimming pelagic shark found at high latitudes in both hemispheres. To examine the influence of temperature on porbeagle distribution, a detailed analysis of the relationship between catch rate, temperature, depth and location was carried out based on 420 temperature profiles taken during commercial fishing operations. More than half of the porbeagle were caught at temperatures of 5–10°C (at the depth of the hook); the mean temperature at gear of 7.4°C differed very little among seasons. Most of the spring fishing took place near fronts, although the affinity with fronts was not evident in the fall. Temperature at depth was a significant modifier of catch rate when included in a generalized linear model controlling for the effects of location, fishing vessel, month and year. However, sea surface temperature was a poor predictor of catch rate. The similarity between environmental and catch‐weighted cumulative distribution functions confirmed suggestions that fishers sought out the most appropriate temperature range in which to set their gear. As porbeagle are among the most cold tolerant of pelagic shark species, we suggest that they have evolved to take advantage of their thermoregulating capability by allowing them to seek out and feed on abundant coldwater prey in the absence of non‐thermoregulating competitors.  相似文献   
90.
Pregnancy and interferon-tau (IFN tau) upregulate uterine Mx gene expression in ewes; however, the only known role for Mx is in the immune response to viral infection. We hypothesize that Mx functions as a conceptus-induced component of the anti-luteolytic mechanism and/or regulator of endometrial secretion or uterine remodeling during early pregnancy. This study was conducted to determine the effects of early pregnancy on uterine Mx expression in domestic farm species with varied mechanisms of pregnancy recognition. Endometrium from cows, gilts, and mares was collected during the first 20 d of the estrous cycle or pregnancy, and total messenger RNA (mRNA) and protein were analyzed for steady-state levels of Mx mRNA and protein. Northern blot analysis of Mx mRNA detected an approximately 2.5 Kb of mRNA in endometrium from each species. In pregnant cows, steady-state levels of Mx mRNA increased 10-fold (P < 0.05) above levels observed in cyclic cows by d 15 to 18. In cyclic gilts, slot blot analysis indicated that endometrial Mx mRNA levels did not change between d 5 and 18 of the cycle. However, in pregnant gilts, Mx levels tended (P = 0.06) to be elevated two-fold on d 16 only, and in situ hybridization indicated that this increase occurred in the stroma. In mares, Mx mRNA was low, but detectable, and did not change between ovulation (d 0) and d 20, regardless of reproductive status. Western blot analysis revealed multiple immunoreactive Mx protein bands in each species. One band was specific to pregnancy in cows. As in ewes, in situ hybridization analysis indicated that Mx mRNA was strongly expressed in the luminal epithelium, stroma, and myometrium by d 18 in cows. However, on d 14 in gilts, Mx was expressed primarily in the stroma, and on d 14 in mares, low levels of Mx expression were confined largely to the luminal epithelium. The uteruses of cows, gilts, and mares express Mx, and expression is upregulated during pregnancy in cows and gilts--animals whose conceptuses secrete interferons during early pregnancy, but that possess different mechanisms for pregnancy recognition.  相似文献   
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