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91.
The purpose of this study was to examine the capacity of live brine shrimp Artemia spp. to accumulate metronidazole at different developmental life stages. Metronidazole is used in fish as an antiparasitic medication. An effective drug delivery method is to enrich the Artemia with metronidazole and offer them as live feed to the infected fish, usually ornamental species and other small fishes. Artemia cysts were hatched and then soaked in a metronidazole solution (0.05%) at instars 1-3 of larval development. Our findings indicated that Artemia were able to accumulate metronidazole at levels considered therapeutic to other animals and humans (25-100 mg/kg). However, the levels varied depending on the stage of larval development. Artemia accumulated the highest levels of metronidazole (137-143 mg/kg) when they started filter feeding (instar 2), whereas newly hatched Artemia (instar 1) contained the lowest level (85 mg/kg). Based on this study and a review of the literature, a new protocol recommended for enriching Artemia with metronidazole consists of soaking the Artemia in a 0.05% metronidazole solution for 3 h at room temperature. Because metronidazole is relatively insoluble in water, it must first be dissolved in warm water with continuous stirring.  相似文献   
92.
This study was designed to evaluate the effect of single layer centrifugation (SLC) and subsequent cold storage on stallion sperm capacitation‐like status and acrosome reaction. Three stallions were included in the study, with three ejaculates per stallion. The samples were examined 4, 24 and 72 h after collection, extension and SLC, with storage at 6°C. Sperm capacitation‐like status was investigated using the fluorescent dye chlortetracycline (CTC). There was no difference in capacitation‐like status between colloid‐selected and non‐selected spermatozoa. Sperm motility decreased significantly during cold storage, whereas the proportion of apparently capacitated spermatozoa increased. There was no change in the proportion of acrosome‐reacted spermatozoa. In conclusion, SLC through Androcoll?‐E does not adversely affect the capacitation‐like status of stallion spermatozoa, although it did increase with time during cold storage.  相似文献   
93.
Seminal plasma (SP) contains several types of compounds derived from the epididymides and accessory glands. The aim of this study was to examine the protein composition of different ejaculate fractions. Trial I: fractionated ejaculates were collected from two normal and two subfertile stallions. Samples containing pre‐sperm fluid and the first sperm‐rich jets (HIGH‐1), the main sperm‐rich portion (HIGH‐2), the jets with low sperm concentrations (LOW), and a combined whole‐ejaculate (WE) sample was centrifuged, and the SP was filtered and frozen. A part of each SP sample was stored (5°C, 24 h) with spermatozoa from HIGH‐2 and skim milk extender. Sperm motility was evaluated after storage in extender mixed with the stallion’s own SP or SP from one of the other stallions (sperm from a normal stallion stored in SP from a subfertile stallion and vice versa). Protein composition was analysed using reverse‐phase liquid chromatography (RP‐HPLC), N‐terminal sequencing and mass spectrometry. The area‐under‐the‐curve (AUC) was used for quantitative comparison of proteins within fractions. Trial II: semen samples were collected from seven stallions. Fractions with the highest (HIGH) and lowest (LOW) sperm concentrations and WE samples were examined using SDS‐PAGE and densitometry. No significant differences emerged between fractions in the AUC‐values of the Horse Seminal Protein‐1 (HSP‐1) and HSP‐2 peaks, or the peak containing HSP‐3 and HSP‐4 (HSP‐3/4). Levels of HSP‐1, HSP‐2 and HSP‐3/4 were not significantly correlated with total sperm motility, progressive sperm motility or average path velocity after storage. Significant differences between ejaculate fractions in the amount of different protein groups present in SP were not found in Trial I; but in Trial II, the proteins in the 60–70 kDa range were more abundant in LOW than in HIGH and WE, indicating that this band contained proteins derived mainly from the seminal vesicles, which produce most of the SP in LOW.  相似文献   
94.
Objectives: To (1) describe vascular distribution in the grossly intact canine cranial cruciate ligament (CCL) using immunohistochemical techniques specific to 2 components of blood vessels (factor VIII for endothelial cells, laminin for basement membrane); and (2) compare the vascularity in different areas of interest (craniomedial versus caudolateral bands; core versus epiligamentous regions; and proximal versus middle versus distal portions) in the intact normal canine CCL. Study Design: In vitro study. Animals: Large, mature dogs (n=7) of breeds prone to CCL disease that were euthanatized for nonorthopedic conditions. Methods: Intact CCL were collected from fresh canine cadavers free from stifle pathology. CCL tissue was processed for immunohistochemistry and stained for factor VIII and laminin. Vascular density was determined by histomorphometric analysis. Results: Specific vascular staining was sparsely identified throughout the CCL; however, the proximal portion of the CCL appears to have a greater number of vessels than the middle or distal portion of the ligament. Conclusions: The CCL is a hypovascular tissue and its vascular distribution is not homogeneous.  相似文献   
95.

Purpose  

Tessier's sequential extraction method is usually used to study metal parting among different phases in soils. The main objective of this study was to determine the redistribution of trace metals which were added simultaneously to a sandy loam soil by use of the fractional distribution and reduced partition indexes and the risk of assessment code (RAC).  相似文献   
96.
97.
Cataiase, peroxidase and IAA‐oxidase activities, so as odiphenolics content in sunflower leaves grown in hydroponics with 4 B levels (0.05; 0.25; 0.5 and 2.0 ppm) were determined. The biochemical assays were made when visual symptons were clearly developed.

Cataiase activity significantly increased in B deficient leaves. Peroxidase, IAA‐oxidase activities and o‐diphenolics content did not significantly change with B levels. The lag period for IAA‐oxidase activity was significantly reduced in B deficient and toxic leaves with respect to the normal ones. These results are in accordance with the hypothesis that one of the B action could be to enhance cataiase activity, the “in vivo” decrease of H2O2 levels beeing the cause of the variation in other enzymatic activities related with that substrate.  相似文献   

98.
甘蓝型油菜高含油量隐性胞核雄性不育两型系的选育   总被引:2,自引:0,他引:2  
采用复合回交方法,选育出甘蓝型油菜双低隐性核不育两型系。双低不育系121AB、123AB、175AB、932AB、933AB等表现高含油量、产量高等性状,品质优良。其中175AB、932AB、933AB含油量42.7%~44.0%,蛋白质含量24.2%~25.3%。组配的德油系列优质杂交油菜新组合在比较试验中均比对照种油研七号增产,增产率9.98%~27.34%,表现出较大的增产潜力。  相似文献   
99.
The development of a core collection, one which represents the genetic diversity of a crop with minimal redundancy and increases utility of the collection as a whole, is especially important as the funding for germplasm collections decreases. With limited resources, it is difficult to manage large germplasm collections and disperse genetically diverse germplasm to plant breeders. An algorithm was developed to assist in selection of core collections based on estimates of genetic distance. The criteria for selection of the maximum genetically diverse set were based on rankings of genetic distance between an accession with respect to all other accessions. Depending on the size core which a user wished, a zone around each selected accession was determined and no other accession within these limits was selected. The premise for the algorithm was that the genetic variability represented in the core must be representative of the distribution of genetic distances within the population of interest. In the present study, the algorithm was used with RAPD-marker-based estimates of genetic distance for 270 Theobroma cacao L. accessions and 134 Capsicum accessions that chose a set representing 18.5% of the population and representing the breadth of RAPD-based variation.  相似文献   
100.
A serological survey using indirect immunofluorescence (IFAT) for bovine babesiosis (Babesia bovis and B. bigemina) and card test for anaplasmosis, indicates that these haemoparasites are widespread in Martinique. The high prevalences (62% for B. bovis, 52% for B. bigemina and 43% for Anaplasma marginale) lead to the hypothesis of an unstable epizootic situation for these three haemoparasitic diseases. However, the number of smears examined was too low to evaluate their clinical incidence. Both the American and Cuban card tests gave similar results in the detection of antibodies to A. marginale. Theileria mutans is described for the first time in Martinique. Trypanosomosis (Trypanosoma vivax) has disappeared from Martinique, on clinical and serological evidence.  相似文献   
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