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11.
The wolfberry (Lycium barbarumL.) fruit has been used in traditional Chinese medicine and food, but fruits grown in various geographic areas are significantly different in quality and content of functional components. In this study, we tested the internal nutritional ingredients and related environmental factors using forty-two wolfberry fruits collected from seven wolfberry producing regions in China (Yinchuan and Zhongning in Ningxia, Jingyuan in Gansu, Nuomuhong Farm in Qinghai,Hangjinhouqi and Wulateqianqi in Inner Mongolia, and Jinghe in Xinjiang). The nutritional ingredients of the forty-two wolfberry fruits are dependent on the environment. Correlation analysis revealed that the amount of nutrients was highly related to each other. Based on the analysis ofratio of total sugar to betaine (sugar-alkali ratio), we have successfully established quality standards for the wolfberry based on the levels of betaine and sugar. The standards were as follows: high betaine low sugar (sugar-alkali ratio≤15.1), high betaine medium sugar (15<sugar-alkali ratio≤60), medium betaine medium sugar (60<sugar-alkali ratio≤121), medium betaine high sugar (121<sugar-alkali ratio≤165), and low betaine high sugar (sugar-alkali ratio>165). Zhongning of Ningxia is the geo-authentic producing region of the wolfberry, whereby the wolfberries are rich in main pharmacological ingredients Lycium barbarum polysaccharide (LBP) and three trace elements (iron, manganese and selenium) and medium sugar-alkali ratio. In addition, the correlation analysis showed that both the altitude and average temperature difference between day and night had positive effects on the wolfberry flavonoids content but the annual sunshine duration negatively affected the betaine contents of the wolfberry fruit.  相似文献   
12.
PurposeNew promising detectors are available for measuring small field size output factors (OFs). This study focused on a multicenter evaluation of two new generation detectors for OF measurements on CyberKnife systems.MethodsPTW-60019 microDiamond and W1 plastic scintillation detector (PSD) were used to measure OFs on eight CyberKnife units of various generations for 5–60 mm fixed cones. MicroDiamond and PSD OF were compared to routinely used silicon diodes data corrected applying published Monte Carlo (MC) factors. PSD data were corrected for Čerenkov Light Ratio (CLR). The uncertainties related to CLR determination were estimated.ResultsConsidering OF values averaged over all centers, the differences between MC corrected diode and the other two detectors were within 1.5%. MicroDiamond exhibited an over-response of 1.3% at 7.5 mm and a trend inversion at 5 mm with a difference of 0.2%. This behavior was consistent among the different units. OFs measured by PSD slightly under-responded compared to MC corrected diode for the smaller cones and the differences were within 1%. The observed CLR variability was 2.5% and the related variation in OF values was 1.9%.ConclusionThis study indicates that CyberKnife microDiamond OF require corrections below 2%. The results are enhanced by the consistency observed among different units. Scintillator shows a good agreement to MC corrected diode but CLR determination remains critical requiring further investigations. The results emphasized the value of a multi-center validation over a single center approach.  相似文献   
13.
How to assort with the relationship between the urban construction and the maintenance of ecological security is a hot issue during the process of urbanization. The purpose of this study is to identify the key ecological land maintaining ecological security and to put forward some measures for environmental management. Based on the GIS technology, from the view of water security, biodiversity conservation, disaster protection, natural recreation security, and human disturbance, an integrated index is put forward to evaluate the ecological importance of regional space. Then, a GIS-based approach for evaluating ecological importance was created, with Xingguo county of China as a case study. The results show that the area of core eco-space in the study area accounts for 30% of the total area. These areas mainly consist of the core areas of regional river systems, wetlands, nature reserves, forest parks, and scenic spots and the endangered and protected zone of geological hazards. According to the spatial characteristics of ecological importance for different regions, this study proposes some zoning regulations and measures for environmental management.  相似文献   
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Cyanobacteria blooms may present a public health concern in sources of drinking water and recreational water due to the production of toxins by some species, microcystins being the most commonly found. It is possible to detect microcystins using instrumental analyses and field test kits. While instrumental analysis methods are accurate, they are also costly, and in regions with a high incidence of blooms the time to report is lengthy (days). On the other hand, the use of commercially available test kits may provide quicker results at a lower cost. The purpose of this work was to evaluate three commercially available kits: the Immunochromatographic Strip Test for the Detection of Microcystins and Nodularins in Source Drinking Water at 1 μg/L (Abraxis strip test), the Abraxis Microcystin Tube Kit and the Envirologix QualiTube Kit. The evaluation of each kit focussed on the interpretation of the results by the end-user and the validity of a test kit was based on four indices: sensitivity, specificity, positive predictive rate (PPR) and negative predictive rate (NPR) (false positive/negative) based on the manufacturer's specifications. The results indicate that there are challenges in the visual interpretation of the results at levels close to the threshold value for each kit. The scope of each kit must be understood: free vs. total, qualitative vs. semiquantitative. For instance, the Envirologix Qualitube Kit does not provide a lysing agent, therefore it will underestimate the levels of total microcystin if a lysing step is not included. In the case of the Abraxis strip test, the kit provides information on the absence/presence of microcystin at a threshold value of 1 μg/L, but false positives were encountered.  相似文献   
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A series of novel HIV-1 protease inhibitors has been designed and synthesized, which contained morpholine derivatives as the P2 ligands and hydrophobic cyclopropyl as the P1 ligand at the meantime in this study, with the aim of improving the interactions between the active sites of HIV-1 protease and the inhibitors. Twenty-eight compounds were synthesized and assessed, among which inhibitors m18 and m1 exhibited excellent inhibitory effect on the activity of HIV-1 protease with IC50 value of 47 nM and 53 nM, respectively. The molecular modeling of m1 revealed possible hydrogen bondings or van der Waals between the inhibitor and the protease, worthy of in-depth study.  相似文献   
18.
The nature and persistence of seed quality effects produced by a range of seed production treatments was investigated in the autumn-sown onion crop. Genotypically equivalent seed lots raised in different glasshouses within the same year were found to germinate at significantly different rates. The seed lot which emerged earlier produced larger seedlings and this difference in size persisted throughout the growing period. In a comparison between the effects of hand crossing and self-pollination techniques the hand crossing method produced a much lower total seed yield but heavier seeds and larger plants. The induced effects persisted throughout the year but were not significant in the mature bulb characters. The implications of these results upon the control of seed production for plant breeding and genetical experiments is discussed.  相似文献   
19.
Zusammenfassung Die serotoninhaltigen, nach Formaldehydbedampfung im UV-Licht gelbfluoreszierenden EC-Zellen im Magendarmepithel wurden bei normalen und bei tryptophanfrei ernährten Ratten untersucht. Bei Kontrolltieren ist die Zahl der EC-Zellen, bezogen auf die Schleimhautfläche, im Duodenum größer als im Pylorus. Im Duodenum sind die EC-Zellen etwa gleichmäßig auf Oberflächen- und Drüsenepithel verteilt, im Pylorus ganz überwiegend im Drüsenepithel lokalisiert. Die Brunnerschen Drüsen besitzen keine EC-Zellen. Tryptophanfreie Diät führt zu starker Abnahme des Serotoningehalts der EC-Zellen, nach Umsetzung auf Normalkost steigt er wieder an. — Die Ergebnisse sprechen weiterhin dafür, daß die EC-Zelle sowohl Speicher- als auch Syntheseort von Serotonin ist. Dabei kommt Serotonin in der EC-Zelle wahrscheinlich in zwei Fraktionen vor, nämlich zytoplasmatisch gelöst und granulagebunden. Die histochemischen Nachweismethoden für Serotonin, Möglichkeiten des Eingriffs in die verschiedenen Syntheseschritte des Serotonins und deren Spezifität in bezug auf die EC-Zelle als physiologischem Ort der Serotoninsynthese werden diskutiert.
Studies on the endocrine cells of the gastrointestinal tractII. Fluorescence microscopy of the EC-cells after tryptophan-free diet
Summary The serotonin-containing EC-cells of the gastro-intestinal mucosa, which show yellow fluorescence after treatment with gaseous formaldehyde, were investigated in the rat after normal and tryptophan-free nourishment. In control animals the number of EC-cells, related to epithelium area is higher in the duodenum than in the pyloric region. In the duodenum the EC-cells show about the same distribution in surface epithelium and gland epithelium. In the pyloric region EC-cells are localized predominantly in the gland epithelium. No EC-cells were found in the Brunner glands. After tryptophan-free diet the serotonin-level of the EC-cells strongly decreases; serotonin-level increases after return to normal nourishment. The results also suggest, that serotonin is synthesized as well as stored in the EC-cell and that it occurs in two fractions: bound to granules and dissolved in the cytoplasm. Discussion deals with the histochemical methods for determination of serotonin, the possibilities of influencing the pathways of serotonin metabolism and the specificity of these possibilities concerning the EC-cell as the physiological site of serotonin synthesis.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft, Antrag Fo 77, 1–4.  相似文献   
20.
Summary A quantitative evaluation has been made of the sizes of neuronal granular vesicles (GV) in different (sub-)zones of the rat median eminence. On the basis of the frequency distribution of the mean sizes of the GV in the individual nerve profiles, at least 4 tentative categories of nerve profiles may be distinguished. However, available data do not permit characterization of nerve fibre categories in terms of neurohormone and/or neurotransmitter storage. From dorsal to ventral the palisade zone shows a decrease in mean size of GV; furthermore, the relative number of nerve profiles characterized by small GV (mean size smaller than 112 nm) increases. In contrast, the GV in the zona granulosa, that part of the external zone of the median eminence ventral to the palisade zone, are of relatively large size. Qualitative observations indicate that the zona granulosa may be regarded as an area for both storage and release of biologically active substances. We are grateful to Mrs. R.M.Y. Hartsteen for technical assistance, to Miss P.C. Delfos and Mr. W. van den Oudenalder for photographic assistance and to Prof. J. Moll for helpful criticism.  相似文献   
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