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11.
A highly efficient, stable, and cost-effective micropropagation protocol for the conservation of a medicinal plant Turnera ulmifolia L. was established from nodal tissues via multiple axillary shoot proliferation on using Murashige and Skoog’s (MS) liquid nutrient medium. To begin with, nodal explants were placed on agar gelled medium amended with 2.0 mg L?1 6-benzylaminopurine (BAP) and 0.1 mg L?1 indole-3 acetic acid (IAA) for shoot induction. Subsequently, elongation of regenerated shoots could be possible on liquid MS medium supplemented with 0.5 mg L?1 BAP and Kin (kinetin) each along with 0.1 mg L?1 IAA where high frequency of regeneration in terms of number of shoots (47.2 shoots/explant) was achieved. Furthermore, long and healthy shoots (4?5 cm in length) were rooted on agar gelled half-strength of MS medium supplemented with 2.0 mg L?1 indole-3 butyric acid (IBA). Finally, in vitro regenerated plantlets were gradually acclimatized in the greenhouse and transferred to the field successfully.  相似文献   
12.
This study characterized soil chemical and microbiological properties in hay production systems that received from 0 to 600 kg plant-available N (PAN) ha−1 year−1 from either swine lagoon effluent (SLE) or ammonium nitrate (AN) from 1999 to 2001. The forage systems contained plots planted with bermudagrass (Cynodon dactylon L.) or endophyte-free tall fescue (Festuca arundinaceae Schreb.). In March 2004, the plots were sampled for measurements of a suite of soil chemical and microbiological properties. Nitrogen fertilization rates were significantly correlated with soil pH and K2SO4-extractable soil C but not with total soil C, soil C/N ratio, electrical conductivity, or Mehlich-3-extractable nutrients. Soil supplied with SLE had significantly lower Mehlich-3-extractable nutrients than the soil supplied with AN. Two indicators of soil N-supplying capacity (potentially mineralizable N and amino sugar N) varied with plant species and the type of N fertilizer. However, they generally peaked at an application rate of 200 or 400 kg PAN ha−1 year−1. Soil microbial biomass C also peaked at an application rate of 200 or 400 kg PAN ha−1 year−1. Nitrification potential was significantly higher in soil supplied with AN than in the unfertilized control but was similar between SLE-fertilized and unfertilized soils. Our results indicated that an application rate as high as 600 kg PAN ha−1 year−1 did not benefit soil microbial biomass, microbial activity, and N transformation processes in these forage systems.  相似文献   
13.
1. Experiments were conducted to study the welfare and meat quality effects of shackling. In experiment 1, broilers with or without leg problems were shackled (S) for 4 min on a moving line and blood sampled; or handled (H), returned to the crate and sampled after 4 min; or sampled immediately after removal from the crate (control, C).

2. Plasma corticosterone (CORT) concentrations, as measured by radioimmunoassay, were highest in S and lowest in C, while the H group was intermediate. Leg problems had no effect on CORT.

3. In experiment 2, tonic immobility (TI) was induced in broilers after 2 min inverted handling to determine fear responses. One week later, the birds were fasted, transported and then shackled on a moving shackle line for 0, 1, 3 or 4 min, then unshackled and blood sampled. Wing flapping during shackling was also quantified.

4. Shackling time did not influence CORT concentrations. There was a negative correlation (r= ? 0.714) between CORT and wing flapping duration in the 1 min shackling treatment. There was no relationship between TI and wing flapping or CORT.

5. In experiment 3, broilers were exposed to two food withdrawal (FW) times (food withdrawn overnight or during crating only) and held for 4 h prior to processing, shackled (0, 2 or 4 min shackling time, ST), and then killed by exsanguination. Blood samples were collected during the neck‐cut. Pectoralis superficialis and Supracoracoideus samples were either collected after 15 min and individually quick frozen (IQF) in liquid nitrogen or collected at 4 h post mortem from carcases chilled on slush ice (COI).

6. CORT increased significantly with increased ST. There was a FW × ST interaction effect on the initial pH of fillets. ST influenced the b*, chroma and Hue values of the COI fillets. FW influenced the L* and Hue values of both IQF and COI fillets as well as the a* value of the COI fillets.

7. In summary, CORT increased with shackling time when birds were held after transport. FW and ST also influenced the colour of fillets, although it is not clear whether these changes are perceptible to the consumer. The duration of wing flapping during shackling did not appear to be related to fearfulness, although it was influenced by properties of the shackle line. We suggest that there be a maximum time lapse between shackling and stunning or killing of 2 min to minimise stress and meat quality changes.  相似文献   

14.
Objective: To describe the indications, clinical features, outcomes and complications associated with use of continuous renal replacement therapy (CRRT) in 17 client-owned dogs and 16 client-owned cats with acute or acute-on-chronic renal failure refractory to aggressive medical management.
Series summary: Twenty-nine percent of dogs and 44% of cats had evidence of pre-existing chronic kidney disease (CKD). Median duration of CRRT was 16.3 hours (range 0.3–83.0 hours) in dogs and 11.5 hours (range 1.0–35.5 hours) in cats. Median canine blood urea nitrogen (BUN) improved from 41.0 mmol/L (115.0 mg/dL) to 11.8 mmol/L (33.0 mg/dL) and creatinine from 636.5 mmol/L (7.2 mg/dL) to 274 mmol/L (3.1 mg/dL). Median feline BUN improved from 46.4 mmol/L (130 mg/dL) to 13.9 mmol/L (39.0 mg/dL) and creatinine from 1069.6 mmol/L (12.1 mg/dL) to 291.7 mmol/L (3.3 mg/dL). Metabolic acidosis resolved in 80% of affected dogs and 71% of affected cats. Hyperkalemia resolved in 100% of affected dogs and 88% of affected cats. Complications noted with CRRT included iatrogenic hypokalemia, iatrogenic metabolic alkalosis, clinical hypocalcemia, total hypercalcemia, filter clotting, anemia, hypothermia, and neurologic complications. Forty-one percent of dogs and 44% of cats survived to discharge. No dogs and only 1 cat developed newly diagnosed CKD.
New or unique information provided: CRRT can be a viable option for the management of acute or acute-on-chronic renal failure in dogs and cats that are refractory to aggressive medical management. The frequency of complications associated with CRRT in this study warrants further experience with this modality before its widespread use can be recommended.  相似文献   
15.
Concentrations of total mercury (Hg), methyl Hg and Hg(II) were determined in coastal marine sediments collected from the Baltic, South China and the Bering Seas. Methyl Hg concentrations in sediments were between 0.01 and 2 ng g-1 on a dry weight basis, accounting for only <1% of the total Hg concentrations. The percentage of Hg(II) (i.e. available Hg) in total Hg was between 5 and 13 suggesting that most of the Hg in sediments was bound as HgS and/or Hg-humic complexes. Relatively larger proportion of methyl Hg was found in less polluted freshwater sediments than in marine sediments. Methyl Hg concentrations in marine sediments were not found to be correlated with total Hg and/or Hg (II) concentrations.  相似文献   
16.
India being the primary center of origin for rice had a very large treasure of local land races, most of which are out of cultivation today. The exact genetic potential and their differences from commercial varieties and the magnitude of heterogeneity still present in them are not well catalogued. Hence the need to characterize the available land races has become imminent in the modem day concept of crop improvement (Rezai and Frey, 1990). The present study addresses the utility of SSR markers in divulging the genetic relationships at molecular level among the major component factions office gennplasm viz., local cultivars, land races and wild species collected from a wide range of agro-geographical regions of Indian subcontinent.  相似文献   
17.
传染性支气管炎的新动态   总被引:1,自引:1,他引:0  
1传染支气管炎病毒的变异 1.1 变异特性 传染性支气管炎病毒(IBV)很重要的特性是会发生变异,它是一种不断进化的病毒.病毒表面的s蛋白很重要,与病毒的中和反应、HI活性、免疫性及血清定型相关.S蛋白由S1和S2蛋白组成,S1蛋白基因的改变是病毒不断进化的原因.  相似文献   
18.
19.
In vitro iron availability was determined from a standard cereal meal (C) with and without the addition of protein isolates from bovine milk (BP), groundnut milk (GP) and soybean milk (SP). A second set of studies were done to investigate the potentially available iron from fenugreek leaves per se and the effect of their addition on the available iron from the cereal meal. The potentially available iron from the meal increased from 4.91% to 6.73% on the addition of BP. The next best enhancer was GP (4.91% to 6.17%). Although the addition of SP increased the total iron content of the cereal meal significantly, the percent available iron decreased compared to the other milk proteins. The addition of fenugreek leaves (100 g/meal) to the meal increased the total iron content of the meal significantly (3.24 mg to 9.12 mg) (p<.001), however, the available iron was observed to decrease (4.91% vs 4.34%).  相似文献   
20.
Synthetic musks are used in many consumer products for their pleasant odor and their binding affinity for fabrics. In the early 1990s, polycyclic musks were reported to occur in air, water, sediment, wildlife, and humans from many European countries. Concentrations of polycyclic musks, particularly 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-[??]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene (AHTN), have been reported to increase over time in the environment. In this study, concentrations of musks in water, sediment, fish, and mussel were determined from three locations along the upper Hudson River. HHCB and AHTN were detected in water (n?=?5; 3.95?C25.8 and 5.09?C22.8 ng/L, respectively), sediment (n?=?3; 72.8?C388 and 113?C544 ng/g, dry weight), fish (n?=?30; <1?C125 and <1?C32.8 ng/g, lipid weight), and zebra mussel (n?=?4; 10.3?C19.3 and 42.2?C65.9 ng/g, lipid weight) samples. Bioaccumulation factors of HHCB calculated for white perch, catfish, smallmouth bass, and largemouth bass were in the range of 18 to 371, when the concentrations in fish were expressed on a wet weight basis; the factors were in the range of 261 to 12,900, when the concentrations in fish were expressed on a lipid weight basis.  相似文献   
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