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摘要： Tusked mammals can be terrestrial or aquatic. Many of these magnificent animals are kept in captivity all over the world. Functions of tusks vary as much as the species in which they occur. Dental anomalies and disorders of tusks and the rest of the dentition in these mammals were discussed, with an emphasis on the elephant. The tusk anatomy, with its large, conically-shaped pulp, makes it an ideal tooth for partial pulpectomy treatment in trauma cases where the pulp is exposed. Surgical techniques for tusks have been developed and were discussed. Oral tumors occur, but are rare.

关键词： BREEDING   GENETICS   POPULATION biology   FEMALES   FERTILITY   REPRODUCTION  

摘要： Eleven populations of the Pan-American sandy beach isopod Excirolana braziliensis, distributed from tropical (9degreesN) to temperate (39degreesS) sandy beaches in Atlantic and Pacific Oceans, were analyzed to determine latitudinal variations in: breeding and recruitment patterns. sex ratios. size of ovigerous females and of juveniles and length-fecundity relationships. E. braziliensis exhibited strong latitudinal patterns in all reproductive traits throughout its distribution range. Breeding and recruitment shifted from continuous to seasonal from tropical to temperate beaches, having a predominance of females at higher latitudes. In agreement with the latitudinal gradient hypothesis, ovigerous females inhabiting tropical sandy beaches (low latitudes) were smaller, became sexually mature at smaller sizes and had lower individual fecundity than on temperate beaches. Juveniles were also smallest at low latitudes. Between-ocean comparisons showed very similar reproductive characteristics for roughly the same latitude. These linked reproductive parameters suggest that the intensity of breeding effort is associated with the duration of the breeding season and geographically size-related characteristics of the species. Geographic variations in the breeding and recruitment seasons, as well as in individual fecundity, size structure of mature females and sex ratios, are proposed to have major consequences in explaining local variations in population demography. Our paper also reinforces the notion that sandy beach animals are highly plastic.

摘要： It is hoped that this article has shown some of the amazing breadth of research into invertebrate mouthpart anatomy, development and pathology, and its relation to important disease processes that impinge on fields as diverse as environmental toxicology and antimalarial therapeutics, while also highlighting the need for further study in this field.

关键词： image registration   fiduciary markers   rodent imaging  

摘要： The objective of this work was to develop and then validate a stereotactic fiduciary marker system for tumor xenografts in rodents which could be used to co-register magnetic resonance imaging (MRI), PET, tissue histology, autoradiography, and measurements from physiologic probes. A Teflon(TM) fiduciary template has been designed which allows the precise insertion of small hollow Teflon rods (0.71 mm diameter) into a tumor. These rods can be visualized by MRI and PET as well as by histology and autoradiography on tissue sections. The methodology has been applied and tested on a rigid phantom, on tissue phantom material, and finally on tumor bearing mice. Image registration has been performed between the MRI and PET images for the rigid Teflon phantom and among MRI, digitized microscopy images of tissue histology, and autoradiograms for both tissue phantom and tumor-bearing mice. A registration accuracy, expressed as the average Euclidean distance between the centers of three fiduciary markers among the registered image sets, of 0.2 +/-0.06 mm was achieved between MRI and microPET image sets of a rigid Teflon phantom. The fiduciary template allows digitized tissue sections to be co-registered with three-dimensional MRI images with an average accuracy of 0.21 and 0.25 mm for the tissue phantoms and tumor xenografts, respectively. Between histology and autoradiograms, it was 0.19 and 0.21 mm for tissue phantoms and tumor xenografts, respectively. The fiduciary marker system provides a coordinate system with which to correlate information from multiple image types, on a voxel-by-voxel basis, with sub-millimeter accuracy-even among imaging modalities with widely disparate spatial resolution and in the absence of identifiable anatomic landmarks. (C) 2003 American Association of Physicists in Medicine.

摘要： The class Amphibia includes three orders. Gymnophiona (caecelians), Urodela(salamanders and newts), and Anura (frogs and toads). The feeding behaviors and anatomicalvariations of amphibians differ according to whether the adults of the species areprimarilyterrestrial or aquatic. The pathology of the oral cavity is less well described for amphibianscompared with the higher orders of animals and is mainly traumatic or nutritional in origin;secondary bacterial infection is common in either *** disease is not a common feature andhas not been described in the literature.

关键词： molecular imaging   SPECT   image reconstruction   radiation detectors   scintillation   functional genomics  

摘要： Molecular imaging can be defined as the characterization and measurement of biological processes in living animals, model systems and humans at the cellular and molecular level using remote imaging detectors. An example concerns the mapping of the distributions of radioactively labeled molecules in laboratory animals which is of crucial importance for life sciences. Tomographic methods like Single Photon Emission Computed Tomography (SPECT) offer a possibility to visualize distributions of radioactively labeled molecules in living animals. Miniature tomography systems, derived from their clinical counterparts, but with a much higher image resolution are under development in several institutes. An example is U-SPECT that will be discussed in the present paper. Such systems are expected to accelerate several biomedical research procedures, the understanding of gene and protein function, as well as pharmaceutical development. (C) 2003 Elsevier Science B.V. All rights reserved.

标准号: BS EN ISO 6887-4-2003+A1-2011

关键词： 农产品   饲料   生物测定   生物试验   定义(术语)   饮食   稀释   稀释法   鱼肉   鱼制品   鱼类   食品检验   食品   微生物分析   微生物学   比率的   规范(验收)   试样制备   悬浮液   试验室  

标准号: BS EN ISO 6887-3-2003

摘要： This part of ISO 6887 specifies rules for the preparation of fish and fishery product samples and theirsuspension for microbiological examination when the samples require a different preparation from the methoddescribed in ISO 6887-1. ISO 6887-1 defines the general rules for the preparation of the initial suspension anddecimal dilutions for microbiological *** part of ISO 6887 only describes methods of preparation that are applicable to several microorganismssimultaneously. It excludes the preparations that only apply to the detection and/or enumeration of a singlemicroorganism where the methods of preparation are described in the relevant standard concerning thatmicroorganism, for example Vibrio *** part of ISO 6887 is applicable to the following raw, processed, cooked or frozen fish and shellfish andtheir products:a) RAW fish, crustaceans, molluscs and others, including? fish, whole or fillets, with or without skin and heads, and gutted,? fish, salted, dried smoked or pickled,? cephalopods, whole or sliced,? crustaceans, whole, including prawns, crayfish, lobsters, crabs and Norway lobsters,? live gastropods, bivalves, echinoderms and tunicates, and? snails;b) PROCESSED fish, crustaceans, molluscs and others, including? dried, smoked, marinated, salted, pickled and breaded fish or shellfish,? fish, whole or prepared fillets, with or without skin,? surimi and delicatessen fish products,? whole or shelled crustaceans and molluscs, and crustacean and mollusc flesh,? cooked fish, crustaceans, molluscs, holothurians, tunicates, shellfish and snail-based dishes;c) FROZEN fish, crustaceans, molluscs and others, in blocks or otherwise, including? fish, fish fillets and pieces,? whole and shelled prawns,? flaked crab,? cephalopods, and? shelled cooked shellfish and shelled snails.

关键词： 农产品   饲料   生物测定   生物试验   定义(术语)   饮食   稀释   稀释法   食品检验   食品   微生物分析   微生物学   比率的   规范(验收)   试样制备   悬浮液   试验室  

标准号: BS EN ISO 6887-4-2003

摘要： This part of ISO 6887 specifies rules for the preparation of samples and decimal dilutions for the microbiological examination of food products other than those covered in other parts of ISO 6887. ISO 6887-1 defines the general rules for the preparation of the initial suspension and decimal dilutions for microbiological examination. This part of ISO 6887 only describes methods of preparation that are applicable to several microorganisms simultaneously. It excludes the preparations that only apply to the detection and/or enumeration of a single microorganism where the methods of preparation are described in the relevant International Standard concerning that microorganism. This part of ISO 6887 is applicable to the following products: — general case for acidic products (see 8.2); — foods with a high fat content, excluding margarine and spreads (see 8.3); — flours, whole cereal grains, cereal by-products, animal feeds and cattle cake (see 9.1); — very hard products, e.g. cassava (see 9.2); — gelatine (see 9.3); — margarine and spreads (see 9.4); — dehydrated products and freeze-dried products (except dairy products and egg products) (see 9.5); — egg and egg products (see 9.6); — fermented products (products containing live microorganisms) (see 9.7); — pastries and cakes (9.8). NOTE Milk and milk products are dealt with in ISO 8261.

关键词： 现代信息技术   生物学   教学   哺乳动物多样性   教学质量   初中  

摘要： 应用现代信息技术手段 ,开展初中生物学“哺乳动物的多样性”教学实践 ,证明能充分调动学生的学习兴趣和积极性 ,有利于改善学习效果 。