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91.
Amination of alkanes has generally required metal catalysts and/or high temperatures. Here we report that simple exposure of a broad range of alkanes to N-triflylimino-λ(3)-bromane 1 at ambient temperature results in C-H insertion of the nitrogen functionality to afford triflyl-substituted amines in moderate to high yields. Marked selectivity for tertiary over secondary C-H bonds was observed; primary (methyl) C-H bonds were inert. Addition of hexafluoroisopropanol to inhibit decomposition of 1 dramatically improved the C-H amination efficiencies. Second-order kinetics, activation parameters (negative activation entropy), deuterium isotope effects, and theoretical calculations suggest a concerted asynchronous bimolecular transition state for the metal-free C-H amination event.  相似文献   
92.
Recent in vitro evidence suggests that the phytol‐derived fatty acids, phytanic acid (PA) and pristanic acid (PrA), are components of animal products with the potential to cause both beneficial and harmful effects on human health. In this study, we investigated the in vivo tissue accumulation of PA and PrA and the changes in tissue lipid profiles, using mice fed a phytol‐containing diet. After 4 weeks of treatment with a diet containing 1.0% phytol, plasma, adipose tissue, liver, and brain were collected and their lipid profiles were biochemically and gas‐chromatographically determined. Dietary phytol caused PA and PrA accumulation in the adipose tissue and liver but not in the brain, and reduced plasma and liver triacylglycerol levels. Phytol intake also decreased the fatty acid concentrations in the adipose tissue, especially polyunsaturated fatty acids such as linoleic acid, but increased the concentrations of these fatty acids in the liver. However, dietary phytol had a low impact on the brain lipid profile. This study suggests that dietary phytol intake caused accumulation of PA and PrA and modified lipid profiles in the adipose tissue and liver, but that the brain is an insusceptible tissue to dietary phytol‐induced changes.  相似文献   
93.
94.
An oligonucleotide probe targeting the rRNA of Erwinia herbicola and Erwinia ananas was designed to detect their cells using fluorescence in situ hybridization. The Cy3-labeled probe hybridized strongly with these species but very weakly with nontarget species such as Erwinia mallotivora, Erwinia nigrifluens, Erwinia cypripedii, Erwinia chrysanthemi, Erwinia carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Escherichia coli. This technique visualized E. herbicola cells after inoculation of kumquat fruits. The probe is promising as a tool for studying population dynamics of E. herbicola and E. ananas.  相似文献   
95.
Edema disease (ED) has become frequent in Japan, but no effective method for experimental infection has been developed. We report here the use of a capsule that resistant against gastric digestion to induce the ED in piglets. Four 21-day-old piglets were used. Shiga toxin 2e-producing Escherichia coli (STEC) cell pellet was encapsulated and administered orally. Two pigs received 1.0x10(10) CFU for two days, and the others received 3.9x10(8) CFU for three days. The high-dose group caused the typical clinical ED signs (palpebral edema or neurologic impairment). Eosinophil infiltration, swollen lymphoid follicles, and edema were observed in the ileum. The kidney had the thrombus in the glomerulus.  相似文献   
96.
A 12-year-old male cat with depression and dyspnoea was presented for investigation. Radiography and computed tomography revealed hydrothorax and solid masses involving the sternum, ribs and thoracic vertebrae. The cat died two days after first presentation, and postmortem examination revealed lung masses and proliferative bony lesions. Histologically, a neoplastic proliferation of epithelial cells was seen in the lungs, with a large amount of collagen and deposits of cholesterin. The bone lesions were also composed of neoplastic epithelial cells and abundant calcified osteoid, without atypia. A diagnosis of pulmonary adenocarcinoma with osteoblastic bone metastases was made. This is the first reported case of osteoblastic metastases in the cat.  相似文献   
97.
Liquid extraction method for determination of myoglobin in muscle is not suitable because of changes in the derivatives and time required. Optical reflectance method is useful as a non‐destructive and real‐time measurement. However, the base line of reflectance method, the muscular reflectance background (MRB) imagined as colorless structural elements, has been unknown because of non‐existence. The spectrum of the base line was analyzed as the analogy of bleached meat. A formula was derived for reflectance that had a linear relationship to the reciprocal of wavelength to the power 4. The reflectance characteristic of the MRB was not constant and the curve tended to rise with increasing wavelength. The reflectance at 700 nm was estimated to be 50%. By the characteristic analysis on Commission Internationale l’Eclairage color values and reciprocal reflectance, it was concluded that the reflectance spectrum of the muscular background obtained in this research was fitted as a base line for the reflectance spectrometry.  相似文献   
98.
A gas chromatographic procedure is described for determining monosodium glutamate (MSG) in several types of food. A sample is extracted with acetone-water (1 + 1). Acetone is evaporated and an aliquot of the extract is buffered with 1M NH4OH-1M NH4Cl pH 9 solution, and chromatographed directly on a column of QAE Sephadex A-25 that has been pretreated with the same buffer. MSG is eluted with 0.1N HCl, and a portion of the eluate is evaporated to dryness and reacted with dimethylformamide(DMF)-dimethylacetal to form the glutamic acid derivative, which is injected into a gas chromatograph and measured by flame ionization detection. Recoveries of MSG from sample fortified at 5-500 mg ranged from 92.8 to 100%.  相似文献   
99.
The species-specific partnership between the sea anemone and anemone fish in many parts of the Indo-Pacific region is a well-known phenomenon. Chemicals secreted by the sea anemone to elicit symbiotic behavior of the fish have been studied for two host-guest pairs, Radianthus kuekenthali (sea anemone)-Amphiprion perideraion (anemone fish) and Stoichactis kenti-A. ocellaris. A new pyridinium compound, amphikuemin, which induces characteristic attracted swimming (toward the chemical stimulus) in A. perideraion, has been isolated from R. kuekenthali and characterized. Several other chemicals that elicit characteristic symbiotic movements have also been identified.  相似文献   
100.
The distribution of oocysts, sporocysts and sporozoites of Eimeria tenella and Eimeria maxima in the digestive tract of chicken and in excreta was investigated. At 1 h after the oral inoculation of E. tenella oocysts, the number of sporocysts in the cecum was 3.4 x 10(6) and decreased gradually thereafter, and the number of sporozoites in the cecum increased and remained at a high level until 12 h after the inoculation. Small numbers of sporocysts and sporozoites of E. tenella were found in other intestinal sites. A great number of E. maxima sporozoites was found, especially in the jejunum, 2 h after the inoculation. The findings that the largest populations of sporozoites of E. tenella and E. maxima were found in the cecum and the jejunum, respectively, indicate that the site specificity of sporozoite invasion for each species is determined before the invasion takes place.  相似文献   
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