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生物制品GMP(WHO,1992)目录1.本指南范围2.原则3.人员4.厂房和设备5.动物设施及管理6.生产7.标签8.批加工记录(格式)和分发记录9.质量保证和质量控制1本指南范围本指南系作为《药品GMP》(见WHOTRS,NO.823)的补充。生...  相似文献   
3.
HMG17 protein is shown to greatly facilitate the catention of double-stranded DNA rings catalyzed by DNA topoisomerases. Even at low DNA concentrations such that catenanes are not observable in the absence of HMG17, the addition of the protein promotes the catenation of greater than 95% of the input DNA into networks that do not enter the gel upon electrophoresis. Electron microscopy and restriction enzyme cleavage experiments indicate that these networks are large structures containing many catenated DNA rings. The HMG17-promoted DNA network formation has been observed with calf thymus type II DNA topoisomerase and the type I topoisomerases of Escherichia coli, Micrococcus luteus, and calf thymus.  相似文献   
4.
A large sample of skulls and associated dentitions of Cormohipparion sphenodus (Cope, 1889). new combination, is described from Miocene deposits of Nebraska, Colorado, New Mexico, and California. This species is morphologically more advanced than the most primitive species of the genus, C. goorisiMacFadden & Skinner, 1981, and more primitive than a third and more advanced species of this genus. C. occidentale (Leidy, 1856). In several characters such as configuration of the preobrital fossa, size, hypsodonty, shape of protocone, and complexity of enamel plication, C. sphenodus is morphologically similar, and potentially related to, some Old World Vallesian «Hipparion. In addition, based on radiometric calibration of stratigraphic sequences in Nebraska and California, C. sphenodus spans an interval of time from about 13.6 to 11 Ma. Inasmuch as the Old World «Hipparion Datum is calibrated at about 12 Ma, we conclude that C. sphenodus exhibits the morphological and chronological prerequisites to have been directly ancestral to some of these Old World forms.The hipparion horses apparently were a polyphyletic assemblage of several genera, and their biogeographic and biochronologic history is more complex than classically thought. Several dispersal events involving these horses may have occurred between the New and Old Worlds during the late Miocene.  相似文献   
5.
Zeng D  Yan M  Wang Y  Liu X  Qian Q  Li J 《Plant molecular biology》2007,65(4):501-509
Starch is the major component of cereal grains. In rice, starch properties determine the eating and cooking quality. The dull endosperm of rice grains is a classical morphological and agronomical trait that has long been exploited for breeding and genetics study. To understand the molecular mechanism that regulates the starch biosynthesis in rice grains, we characterized a classic rice mutant dull endosperm1 (du1) and isolated Du1 through a map-based cloning approach. Du1, encoding a member of pre-mRNA processing (Prp1) family, is expressed mainly in panicles. Du1 specifically affects the splicing efficiency of Wx(b) and regulates starch biosynthesis by mediating the expression of starch biosynthesis genes. Analysis of du1wx shows that Du1 acts upstream of Wx(b). These results strongly suggest that Du1 may function as a regulator of the starch biosynthesis by affecting the splicing of Wx(b) and the expression of other genes involved in the rice starch biosynthetic pathways.  相似文献   
6.
AIMS: Verify the presence and the molecular identity of phytoplasmas in Northern and Central Italy vineyards where yellows diseases are widespread. METHODS AND RESULTS: Phytoplasma presence and identity were determined by PCR/RFLP analyses on 16S ribosomal gene testing 1424 symptomatic samples. The 65% of samples resulted phytoplasma infected; in particular 256 samples were found positive to phytoplasmas belonging to group 16SrV (mainly Flavescence dorée associated), and the remaining 37% was infected by phytoplasmas belonging to ribosomal subgroup 16SrXII-A (Stolbur or Bois Noir associated). 16SrV ribosomal group representative strains were further typed for variability in SecY and rpS3 genes. The results showed the presence of phytoplasmas belonging to 16SrV-C, 16SrV-D and to a lesser extent, 16SrV-A subgroup. CONCLUSIONS: Possible relationships between genetic polymorphisms of phytoplasma strains belonging to subgroup 16SrV-C and their geographic distribution and/or epidemic situations were detected. SIGNIFICANCE AND IMPACT OF THE STUDY: Bois Noir and Flavescence dorée phytoplasmas are present in significant percentages in the areas under investigation. Molecular tools allowed to identify phytoplasma-infected plants and the genes employed as polymorphism markers resulted useful in distinguishing and monitoring the spreading of the diseases associated with diverse phytoplasmas belonging to 16SrV subgroup in vineyards.  相似文献   
7.
A search for phytoplasma-associated diseases was conducted for the first time in the main grapevine-growing localities of the Dukagjini plain in Kosovo. A total of 144 samples were collected from grapevine cultivars displaying leaf yellowing, reddening, discolouration and irregular wood ripening, and analysed using nested and quantitative PCR assays. These assays showed that 35.4% of samples belonging to eight cultivars were positive to the presence of phytoplasmas in the 16SrXII group. The 16S rDNA phytoplasma sequences obtained from 15 samples shared identity greater than 99.5% with ‘Candidatus Phytoplasma solani’. Sequence analysis of the tuf gene showed that the strains found in Kosovar grapevines are in the tuf-type b1 group, sharing 99.6% to 99.8% identity with ‘Ca. P. solani'-related strains associated with the “bois noir” grapevine disease in many European countries; the secY gene sequences, on the other hand, shared 100% identity with ‘Ca. P. solani' strains from Bosnia and Herzegovina, Serbia, Croatia and Turkey. This study constitutes the first report on the presence and molecular characterization of phytoplasmas in Kosovar vineyards. Based on these results, it is recommended that testing for phytoplasma be included in the certification program for grapevine in Kosovo.  相似文献   
8.
A fossil tree was discovered during the 16th century at Jáchymov (Bohemia). The wood was first named by Unger, in 1842, Ulminium diluviale. But it belongs to the Lauraceae family and Felix, in 1883, named it Laurinoxylon diluviale. The authors give the history and the geological setting of the area and describe the anatomy of the wood. The diagnosis of the genus Laurinoxylon Felix, 1883. is emended as follows: heteroxylous fossil wood with average sized solitary vessels or in radial groups; perforation plates simple and sometimes scalariform; intervascular pits alternate and moderately large; thyloses present. Paratracheal parenchyma. Uni to five seriate rays, slightly heterocellular and less than 1 mm high; ray-vessel pits large often stretched. Libriform or with radial pits fibres. Oil cells or mucilage (idioblasts) present. The diagnosis of the species Laurinoxylon diluviale (Unger) Felix, 1883. is also emended. Heteroxylous fossil wood with distinct growth rings; late wood poorly developed with vessels of diameter distinctly smaller as compared to the early wood and with smaller diameter fibres. Diffuse to semiporous vessels, solitary or in radial groups of two to seven , nine to 16 pores/mm2; tangential diameter 100 to 154 μm in early wood and 44 to 72 μm in late wood; vessel length 300 to 550 μm; perforation plates simple and scalariforme (6–12 bars); intervascular pits alternate, rounded (diameter 7–10 μm) or elliptic (long axes × short axes: 10–15 μm × 7–10 μm); thylosis present. Paratracheal parenchyma in more or less complete rows (1–2 cells wide) around the vessels. Heterocellular rays (1–(3) rows of upright cells), of one to five, more frequently three to four cells wide (80%); two to 36 cells high (60 to 820 μm); six to seven rays per tangential millimetre; vessels-rays pits sometimes large, stretched horizontally to vertically. Fibres of 15 to 25 μm in diameter; cell walls of 2–3 μm thick; pits not seen. Oil cells (idioblasts) at the ray margins; 27–60 μm in tangential diameter; 50–80 μm in radial diameter; 72–140 μm high; density of zero to 18 per transversal square millimetres depending on the observed area.  相似文献   
9.
Evidence of fungal activity expressed as typical decay patterns is described from silicified podocarpaceous wood from the Eocene of Patagonia, Argentina. Decay features consist of tracheids of the secondary xylem that are degraded, resulting in thin-celled, lignin-free, translucent, circular to elliptical areas, some of which have cells devoid of all cell wall components including lignin, hemicellulose, and cellulose, and other areas that show only partial simultaneous decay of all cell wall layers. These patterns conform to the white rot and its variant white pocket rot decay patterns produced by basidiomycetes and ascomycetes in gymnosperm and angiosperm wood in modern terrestrial ecosystems. Coagulated opaque bodies in the lumen of some cells and enlarged secondary walls may represent host reactions to infection or remains of metabolic products of fungal enzymatic activity. Similar decay patterns and reaction features have been described from fossil woods ranging in age from the Devonian to the present. This record expands the fossil record of wood rot fungi and underscores their importance as drivers of biological cycles in ancient terrestrial ecosystems.  相似文献   
10.
This paper addresses the visual culture of late-19th-century experimental physiology. Taking the case of Johann Nepomuk Czermak (1828–1873) as a key example, it argues that images played a crucial role in acquiring experimental physiological skills. Czermak, Emil Du Bois-Reymond (1818–1896) and other late-19th-century physiologists sought to present the achievements and perspective of their discipline by way of immediate visual perception (unmittelbare Anschauung). However, the images they produced and presented for this purpose were strongly mediated. By means of specifically designed instruments, such as the cardioscope, the contraction telegraph, and the frog pistol, and of specifically constructed rooms, so-called spectatoriums, physiologists trained and controlled the perception of their students before allowing them to conduct experiments on their own. Studying the material culture of physiological image production reveals that technological resources such as telegraphy, photography, and even railways contributed to making physiological facts anschaulich. At the same time, it shows that the more traditional image techniques of anatomy played an important role in physiological lecture halls, especially when it came to displaying the details of vivisection experiments to the public. Thus, the images of late 19th century physiology stood half-way between machines and organisms, between books and instruments.This paper was written in the context of ten project, The Experimentalizaiton of Life: Configurations of Life Sciences, Art, and Technology (1830–1930). The project is based at the Max Planck Institute for the History of Science (Dept. III: Hans-Jörg Rheinberger), Berlin, and receives funding from the Volkswagen Stiftung, Hannover. A first draft of this paper was presented, accompanied by Sven Dierig on the Virtual Laboratory, at the Institute of Theater Sciences, Free university Berlin, in December 2000. I would like to thank Sven Dierig and the other members of the project as well as Nick Hopwood, Skúli Sigurdsson and the anonymous referees and the editors of this journal for their helpful comments on an earlier version of this paper. Thanks also to Laurie McLaughlin and Nancy Anderson for helping me with the English version of the text.  相似文献   
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