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51.
In criminal investigations, information on the origin of soils may be crucial for solving cases. The biological complexity of soil may potentially be used for sorting and differentiating between soil samples. Nucleic-acid based analyses of soil microbial populations are powerful tools, routinely used in studies of this habitat. Application of such approaches in forensics implies that a standardized DNA extraction method has to be applied to all samples. In this study, several DNA extraction protocols were compared. An improvement on the method proposed by Tsai and Olson (1991) was found to be most suited to extract DNA from various soil types, including from small samples. A blind test on soils from a crime, an alibi scene and unrelated locations was conducted to evaluate the potential of environmental PCR and denaturating gradient gel electrophoresis for use in forensic science. In most cases, soil patterns clustered according to soil type and location.  相似文献   
52.
The baking expansion properties of sour cassava starch (Polvilho azedo) are attributable to photochemical starch degradation induced by heterolactic fermentation after sun-drying. This study investigated the effects of UV irradiation on the different structural levels of cassava starch as compared to those of corn starch and dextrins. Photosensitive compounds excited at 360 and 290 nm in cassava starch were photodegraded when starch was exposed to sunlight or 360 nm irradiation. UV irradiation depolymerized cassava and corn starches, inducing modifications due, at least in part, to a mechanism involving free radicals. Lactic acid was also photodegraded. Photodegradation induced by UV absorption could have been due to fluorescent chromophores found in starches and nonfluorescent chromophores present in glucosidic units.  相似文献   
53.
Canine herpesvirus‐1 (CHV‐1) is known to be associated with fertility and fecundity disorders as well as neonatal mortality in puppies of less than 3 weeks of age. The virus is presumed to be enzootic in dogs all over the world and recent studies in several European countries suggest a high seroprevalence among the dog population. In the year 2000, a total of 647 Belgian canine sera from 102 privately owned patients and 545 breeding dogs were analysed with an enzyme‐linked immunosorbent assay (ELISA). Furthermore 77 of the samples were submitted to two serum neutralization (SN) tests for comparison. An overall CHV‐1 seroprevalence of 45.75% was observed in the Belgian dog population. No significant differences could be observed based on breeding status, reason for consultation or sex. The correlation between the ELISA and both SN tests appeared to be moderate with a significantly greater sensitivity of the ELISA. This study also demonstrated that the CHV‐1 seroprevalence in the Belgian dog population is similar to that in other recently investigated European countries and that the incidence in breeding units is not necessarily higher than in non‐breeding dogs.  相似文献   
54.
The forte of catalytic antibodies has resided in the control of the ground-state reaction coordinate. A principle and method are now described in which antibodies can direct the outcome of photophysical and photochemical events that take place on excited-state potential energy surfaces. The key component is a chemically reactive optical sensor that provides a direct report of the dynamic interplay between protein and ligand at the active site. To illustrate the concept, we used a trans-stilbene hapten to elicit a panel of monoclonal antibodies that displayed a range of fluorescent spectral behavior when bound to a trans-stilbene substrate. Several antibodies yielded a blue fluorescence indicative of an excited-state complex or "exciplex" between trans-stilbene and the antibody. The antibodies controlled the isomerization coordinate of trans-stilbene and dynamically coupled this manifold with an active-site residue. A step was taken toward the use of antibody-based photochemical sensors for diagnostic and clinical applications.  相似文献   
55.
Monkeys injected with monkey retinal tissue incorporated in Freunld's complete adjuvant developed ocular lesions characterized by choroiditic patches in the fundus periphery and sheathing of retinal vessels. Bovine retina, monkey choroid plexus, and guinea pig kidney were ineffective in this respect.  相似文献   
56.
Antibodies that react with predetermined sites on proteins   总被引:23,自引:0,他引:23  
Contrary to previous predictions, relatively short synthetic peptides that mimic part of a protein sequence are routinely capable of eliciting an antiserum that reacts with the partially mimicked protein. Peptides capable of eliciting protein-reactive serums are frequently represented in the primary sequence of a protein, can be characterized by a set of simple chemical rules, and are confined neither to immunodominant regions of intact proteins nor to the amino or carboxyl terminals. As such, synthetic peptide immunogens are valuable for eliciting reagents with predetermined specificity that can be used for basic research. In addition, some synthetic peptides are capable of mimicking regions of virus proteins and eliciting immune responses in animals that are protective against the viral agents. Such peptides may thus serve as the basis for safe, chemically defined synthetic vaccines.  相似文献   
57.
The RNP and Sm antigens recognized by lupus erythematosus antibodies are located on discrete particles containing single small nuclear RNA's complexed with proteins. The antigens Ro and La are also on ribonucleoproteins. The small RNA's in ribonucleoproteins with Ro are discrete, like those associated with RNP and Sm; in contrast, ribonucleoproteins with La contain a striking highly banded spectrum of small RNA's from uninfected cells as well as virus-associated RNA from adenovirus-infected cells.  相似文献   
58.
59.
Precisely detecting oestrus is important for artificial insemination. The aims of this study were to identify oestrus‐specific sow mucus proteins to determine the optimal time for artificial insemination. The proestrous‐ and oestrous‐stage mucus proteins were purified and analysed with proteomic tools such as two‐dimensional gel electrophoresis and matrix‐assisted laser desorption/ionization–time‐of‐flight analyses. Among the differentially expressed proteins, the dimethylarginine dimethylaminohydrolase 2 (DDAH2) protein showed a 3.6‐fold increase during the proestrous stage compared to that during the oestrous stage. A western immunoblot study revealed that two of three sow mucus samples clearly showed negative anti‐DDAH2 antibody activity during the oestrous stage. This study demonstrated that the pig DDAH2 mucus protein exists during the proestrous stage, but not during the oestrous stage, suggesting that mucus DDAH2 could be useful as an oestrus detection marker.  相似文献   
60.
Abstract

CASE HISTORY: Outbreaks of mortality in South Island saddlebacks (Philesturnus carunculatus carunculatus) that had been translocated to two offshore islands in the Marlborough Sounds of New Zealand were investigated during the summer of 2002 and 2007. Both outbreaks were associated with a severe decrease in numbers of saddlebacks of up to 60% of approximately 200 birds.

CLINICAL AND PATHOLOGICAL FINDINGS: Many of the surviving birds were in poor condition, and had skin lesions on the legs and head. Necropsy showed pale liver and lungs, and a swollen spleen. Histopathology revealed schizonts resembling Plasmodium spp. within the cytoplasm of many hepatocytes and splenic histiocytes. The skin lesions consisted of epithelial proliferations containing numerous Bollinger bodies typical of avipox virus (APV) infection. Two different APV were isolated, using PCR, from two different birds exhibiting skin lesions. Each isolate had 100% sequence homology with APV members from either Clade A or Clade B. In addition, PCR analysis revealed that the Plasmodium elongatum present in infected birdsbelonged to a strain that was endemic in the population of North Island saddlebacks (Philesturnus carunculatus rufusater).

DIAGNOSIS: Concurrent infections with Plasmodium spp. haemoparasites and APV were identified as the likely cause of death in the birds examined.

CONCLUSIONS AND CLINICAL RELEVANCE: Although the Plasmodium spp. identified is thought to be endemic to saddlebacks in New Zealand, the affected birds were likely to be immunocompromised by concurrent APV infection or through lack of genetic diversity. Both the introduced mosquito Culex quinquefasicatus and the native mosquito Culex pervigilans are likely vectors for both these diseases, and the provision of water supplies less favourable to mosquito-breeding is recommended.  相似文献   
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