土壤-烟叶中微量营养元素对烤烟吸食品质的影响

对广西中烟主烟区植烟土壤和烟叶中微量营养元素含量进行分析,并对不同产区的烟叶香味成分进行分析,研究这些元素对烟叶香气品质的影响。结果表明,不同产区土壤和烟叶中营养元素含量存在较大差异,且植烟土壤中元素含量对烟叶中营养元素的含量影响较大,从而对烟叶的香味品质产生影响。根据研究提出了具体的施肥建议:依照不同产区土壤营养元素的实际情况,通过施肥调节土壤营养元素含量,协调烟叶中元素含量,从而有效改善烟叶的香气品质。     

土壤大孔隙结构对饱和导水率的影响

[目的]探究土壤不同孔径大孔隙结构特征及数量对土壤饱和导水率的影响,为研究区域土壤水分-溶质迁移规律、水土流失治理与土壤污染防治提供理论参考.[方法]以京郊密云水库五座山林场水源涵养林为研究点,基于工业CT扫描技术,对土柱中土壤大孔隙三维空间结构重建后,探究不同孔径大孔隙结构特征参数密度及数量密度对土壤饱和导水率的影响...     

鸡大肠杆菌(O78)超声波灭活菌苗研究

菌毛提取液,荚膜多糖－破伤风类毒素（ＣＰＳ－ＴＴ）载体抗原液及热、甲醛和超声波灭活菌液中加入蜂胶佐剂,制成菌苗免疫石岐杂鸡,７７及１１２ｄ攻毒保护试验结果表明,超声波灭活菌体的免疫原性最好,热灭活菌体最差,菌毛,ＣＰＳ－ＴＴ及甲醛灭活菌体的免疫原性相当。尤其采用超声波处理的菌液作抗原为明显。     

马铃薯试管苗低成本快繁方式研究

为适应脱毒种薯工厂化生产的要求 ,降低成本 ,对马铃薯脱毒试管苗快繁方式进行了研究 ,以不影响脱毒苗生长为前提 ,筛选出成本低、生长好的培养方法。研究结果表明 :①液体培养由于省去了价格昂贵的琼脂 ,培养成本降低了 80 0 3% ,并且试管苗的生长比固体培养要好 ;②在液体培养过程中 ,不加有机成分 ,培养成本降低 2 3 71% ,脱毒试管苗生长正常 ;③液体培养基的用量要少于固体培养基的用量 ,为固体培养基 1/ 2～ 1/ 3,一般以 10ml为宜     

The effect of dietary Chlorella vulgaris supplementation on micro‐organism community,enzyme activities and fatty acid profile in the rumen liquid of goats

Microalgae might be considered as an alternative source of fat and/or protein for ruminant's diets. However, changes in populations of ruminal micro‐organisms associated with biohydrogenation process, methane and ammonia production in response to microalgae dietary supplementation have not been well characterized. Thus, 16 cross‐bred goats were divided into two groups. Each goat of both groups was fed individually with alfalfa hay and concentrates separately. The concentrates of the control group had no microalgae while those of the treated group were supplemented with 10 g lyophilized Chlorella vulgaris/kg concentrate (chlor). On the 30th experimental day, samples of rumen fluid were collected for microbial DNA extraction, fatty acid profile and enzyme activity analyses. The results showed that the chlor diet compared with the control increased significantly the populations of Methanosphaera stadtmanae, Methanobrevibacter ruminantium and Methanogens bacteria and protozoa in the rumen of goats. A significant reduction in the cellulase activity and in the abundance of Ruminococcus albus, and a significant increase in the protease activity and in the abundance of Clostridium sticklandii in the rumen liquid of goats fed with the chlor diet, compared with the control, were found. Chlorella vulgaris supplementation promoted the formation of trans C_18:1, trans‐11 C_18:1 and monounsaturated fatty acids (MUFA), while the proportions of C_18:0 and long‐chain fatty acids (LCFA) reduced significantly in the rumen liquid of goats. This shift in ruminal biohydrogenation pathway was accompanied by a significant increase in Butyrivibrio fibrisolvens trans C_18:1‐producing bacteria. In conclusion, the supplementation of diets with microalgae needs further investigation because it enhances the populations of methane‐producing bacteria and protozoa.     

ASYMMETRIC NASAL MUCOSAL THICKENING IN HEALTHY DOGS CONSISTENT WITH THE NASAL CYCLE AS DEMONSTRATED BY MRI AND CT

The nasal cycle is a physiological phenomenon that causes regular cyclical congestion and decongestion of the venous sinusoids lining the nasal mucosa. The purpose of this prospective study was to describe magnetic resonance imaging (MRI) and computed tomographic (CT) features of the normal nasal cycle in a group of dogs. Five dogs were recruited that met the following criteria: 8 to 15 months old, nonbrachiocephalic breed, no clinical signs or history of nasal disease, and undergoing anesthesia for problems unrelated to the nasal cavity. Nasal MRI (n = 5) and CT scans (pre‐ and postcontrast, n = 5) were acquired. Images were evaluated subjectively by two board‐certified radiologists and objectively by a diagnostic imaging intern using regions of interest placed on each side of the nasal cavity. Findings were compared using Cohen's kappa coefficient and Students t‐test on log‐transformed data. All dogs showed diffuse unilateral mucosal thickening of the rostral part of the nasal cavity in both MRI and CT studies. This mucosal thickening shifted sides between examinations in three dogs. Changes appeared most marked on T2‐weighted scans. No asymmetric mucosal changes were seen in the mucosa of the ethmoturbinates, vomer–nasal septum, hard palate or the frontal sinuses in any patient on MRI or CT. Computed tomographic contrast enhancement of the thickened mucosa was not statistically significant (P‐value < 0.08). In conclusion, the normal nasal cycle may cause asymmetrical mucosal changes in the rostral part of the nasal cavity that mimic MRI and CT characteristics previously reported for inflammatory disease in dogs.     

DYNAMIC HELICAL COMPUTED TOMOGRAPHY OF THE PITUITARY GLAND IN HEALTHY DOGS

Dynamic helical computed tomography (CT) of the pituitary gland can be used to image the three-dimensional shape and dimensions of abnormalities within the pituitary gland. The aim of this study was to develop a protocol for dynamic helical CT of the pituitary gland in healthy dogs as a future reference study for patients with pituitary disease. Dynamic helical series of nine scans of the pituitary gland during and following contrast medium injection were performed in six healthy dogs using the following protocols: a series with 1 mm collimation and a table feed per X-ray tube rotation of 2 mm (pitch of 2) in six dogs, a series with 2 mm collimation and pitch of 2 in three dogs, and a series with 1 mm collimation and pitch of 1 in three other dogs. Multiplanar reconstructions of the images were made using a reconstruction index of 0.5. Images of all series were assessed visually for enhancement of the arteries, the neurohypophysis, and the adenohypophysis. The enhancement pattern of the neurohypophysis was distinguished adequately from that of the adenohypophysis in five dogs that were scanned with 1 mm collimation and pitch of 2, but the difference was less discernable when the other protocols were used. The carotid artery, its trifurcation, and the arterial cerebral circle were best visualized in dorsal reconstructions. Dynamic helical CT of the pituitary gland in healthy dogs can be performed with 1 mm collimation and pitch of 2, and a scan length that includes the entire pituitary region. Using this protocol, with the specific scanner used, the neurohypophysis, the adenohypophysis, and the surrounding vascular structures are adequately visualized.     

实验猕猴全身CT影像学观察

目的：应用CT技术对成年实验猕猴全身进行断层扫描,探讨CT技术对猕猴疾病的临床诊断意义,建立正常成年猴CT影像图谱,为CT技术在猕猴解剖学的研究、疾病的诊断及科学实验方面的应用,提供影像学的基础资料。方法：（1）选择实验猕猴10只,雌雄各半,年龄6～10岁,进行全身CT断层扫描。（2）试验猴全身麻醉后,置于CT诊断床上,取头前尾后仰卧位,采用平扫及增强扫描技术,进行容积数据采集,获取正常猕猴全身CT影像图片。（3）利用CT图像后处理技术对扫描获得的容积数据进行2D或3D图像重组处理。结果：（1）获得实验猕猴活体结构CT连续断层图像数据集。（2）从扫描和重建图像中精选具有解剖意义的图像,编辑建立实验猕猴CT影像图谱。文中展示4幅代表性扫描图片和5幅三维重建图像。（3）从比较解剖学的角度,阐述猕猴结构特点及与人类的区别。结论：（1）CT影像能够较好显示及分辨猕猴的组织器官结构,骨骼、大血管界面清晰;但软组织、神经、肌肉组织等显示不够清晰。（2）试验获得了正常成年猕猴全身的影像学基础资料,为CT技术在猕猴影像学研究、解剖学研究、疾病的临床诊断及科学实验方面的应用,提供了参考。（3）在猕猴CT影像学方面做了初步摸索,对猕猴进行CT扫描的技术参数选择及猕猴各器官组织定量统计数据的建立等有待进一步总结和完善。     

不同季节四川工夫红茶香气成分的SPME-GC-MS分析

采用固相微萃取(SPME)结合气相色谱-质谱(GC-MS)联用法对采自春、夏、秋3个季节的四川工夫红茶香气成分进行分析。结果表明:共检测到107种香气化合物,其中春茶81种,夏茶46种,秋茶79种,芳樟醇及其氧化物、香叶醇、水杨酸甲酯、苯乙醇、橙花叔醇等31种成分是各季四川工夫红茶的共有成分;在主体香气成分方面,春茶中检出香叶醇、芳樟醇、水杨酸甲酯等18种,夏茶中检出苯乙醇、芳樟醇氧化物Ⅱ、芳樟醇氧化物Ⅳ、3,7-二甲基-1,5,7-辛三烯-3-醇等15种,秋茶检出香叶醇、芳樟醇、苯乙醇、3,7-二甲基-1,5,7-辛三烯-3-醇等18种;春茶和秋茶表现出花香可能与香叶醇、芳樟醇、水杨酸甲酯等含量较高有关,而夏茶和秋茶表现出的桔糖香可能与3,7-二甲基-1,5,7-辛三烯-3-醇有关;春、夏、秋3个季节四川工夫红茶Wickremashinghe-Yamanishi比值分别为0.26、0.62和0.23,表明在香气品质方面秋茶较优,其次为春茶,夏茶稍差,与感官审评结果一致。