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61.
We have developed a multiplex assay covering 16 microsatellite loci, amplified in four polymerase chain reaction (PCR) assays, and loaded on the ABI DNA Analyzer in two separate panels. The assay was tested on 603 individuals originating from wild populations and hatchery stocks of Atlantic sturgeon. The assay was also tested on 12 individuals of European sturgeon and appeared to be almost equally useful. The multiplex assay designed in this study can be successfully applied in studies requiring high genetic resolution, such as relatedness analysis, selective breeding programs, and stock identification of Atlantic sturgeon.  相似文献   
62.
Metallothioneins (MTs) constitutes a superfamily of highly conserved, low molecular weight polypeptides, which are characterized by high contents of cysteine (sulphur) and metals. As intracellular metal-binding proteins they play a significant role in the regulation of essential metals. The major isoforms of the protein (MT-I and MT-II) are induced by numerous stimuli and pathogens but most importantly their induction by metals is closely linked to the physiological metabolism of zinc and protection from the toxic affects following heavy metal exposure. Although the preservation of their genetic expression across animal phyla suggests that MTs may play an important physiological role, MT-I, II knock out (KO) mice survive to adulthood. In both central and peripheral nervous tissues, MT-I, II have neuroprotective roles, which are also induced by exogenous MT-I and/or MT-II treatment. Hence, MT-I, II may provide neurotherapeutic targets offering protection against neuronal injury and degeneration.  相似文献   
63.
The purpose of this study was to investigate the influence of additional resistance training on cardiorespiratory endurance in young (15.8 ± 0.8 yrs) male basketball players. Experimental group subjects (n=23) trained twice per week for 12 weeks using a variety of general free-weight and machine exercises designed for strength acquisition, beside ongoing regular basketball training program. Control group subject (n=23) participated only in basketball training program. Oxygen uptake (VO(2max)) and related gas exchange measures were determined continuously during maximal exercise test using an automated cardiopulmonary exercise system. Muscle power of the extensors and flexors was measured by a specific computerized tensiometer. Results from the experimental group (VO(2max) 51.6 ± 5.7 ml.min(-1).kg(-1) pre vs. 50.9 ± 5.4 ml.min(-1).kg(-1) post resistance training) showed no change (p>0.05) in cardiorespiratory endurance, while muscle strength and power of main muscle groups increased significantly. These data demonstrate no negative cardiorespiratory performance effects on adding resistance training to ongoing regular training program in young athletes.  相似文献   
64.
Current diagnostic tools limit a clinician's ability to discriminate between many possible causes of sensorineural hearing loss. This constraint leads to the frequent diagnosis of the idiopathic condition, leaving patients without a clear prognosis and only general treatment options. As a first step toward developing new diagnostic tools and improving patient care, we report the first use of liquid chromatography-tandem mass-spectrometry (LC-MS/MS) to map the proteome of human perilymph. Using LC-MS/MS, we analyzed four samples, two collected from patients with vestibular schwannoma (VS) and two from patients undergoing cochlear implantation (CI). For each cohort, one sample contained pooled specimens collected from five patients and the second contained a specimen obtained from a single patient. Of the 271 proteins identified with high confidence among the samples, 71 proteins were common in every sample and used to conservatively define the proteome of human perilymph. Comparison to human cerebrospinal fluid and blood plasma, as well as murine perilymph, showed significant similarity in protein content across fluids; however, a quantitative comparison was not possible. Fifteen candidate biomarkers of VS were identified by comparing VS and CI samples. This list will be used in future investigations targeted at discriminating between VS tumors associated with good versus poor hearing.  相似文献   
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66.
A Gram-positive, red-pigment-producing bacterial strain, designated JS520 was isolated from the pristine sediment from the cave on mountain Miroc in Serbia. Strain was confirmed to belong to Streptomyces genus based on phenotypic and genetic analysis. Streptomyces sp. JS520 has the ability to produce exceptionally high amounts of deep red pigment into both solid and liquid media. Liquid chromatography and mass spectroscopy of the purified pigments revealed the major component to be undecylprodigiosin (93?%) with minor component being oxidatively cyclized derivative. The pigment production was affected by medium composition, temperature, pH, and the aeration rate. By medium optimization, yields of undecylprodigiosin of 138?mg?l?1 were achieved, what is the highest level of undecylprodigiosin production reported for the members of Gram-positive Streptomyces genus. Purified pigment had antimicrobial properties against bacterial Bacillus and Micrococcus species (50?μg?ml?1) and against Candida albicans species (100–200?μg?ml?1 range). The ability to affect auto-oxidation of the linoleic acid was demonstrated for the purified undecylprodigiosin, suggesting antioxidative properties of this pigment. Multiple ecophysiological roles of the pigment were revealed by comparing cultures grown under pigment-producing and pigment-nonproducing conditions. Cells grown under undecylprodigiosin-producing conditions could tolerate presence of hydrogen peroxide exhibiting three times smaller zones of inhibition at 100?mM H2O2. Undecylprodigiosin-producing cells were also less susceptible to tetracycline, kanamycin, chloramphenicol, and 8-hydroxyquinoline. While the growth of the cells not producing pigment was completely inhibited by 15?min of exposure to ultraviolet light (254?nm), cells producing undecylprodigiosin and cells supplied with purified pigment in vitro showed survival rates at 22 and 8?%, respectively.  相似文献   
67.
We have developed modified maleimide novel linkers with improved chemical stability that could potentially be used in conjugating various pharmacophores such as oligo nucleotides, peptides, and proteins to antibodies to afford novel biologics with well-defined therapeutic benefits and improved pharmacokinetic properties. These linkers expand the array of tools available for bioconjugation of pharmacophores to antibodies.  相似文献   
68.
The activity of the antioxidant defence enzymes superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), glutathione peroxidase (GSH-Px, EC 1.11.1.9), glutathione reductase (GR, EC 1.6.4.2) and the phase II biotransformation enzyme glutathione-S-transferase (GST, EC 2.5.1.18) in whole mussels (Mytilus galloprovincialis) were studied. The mussels were collected in winter and in spring at two localities in the Adriatic Sea: Bar Port and Tivat Bay. Our results show that the activities of SOD, GSH-Px and GST were seasonally dependent with higher activities in winter. GR activity was also higher in winter, but only in mussels from Bar Port. In mussels from Tivat Bay, GR activity was lower in winter compared to spring. In addition, a decrease in CAT activity in mussels from Bar Port compared to those from Tivat Bay was found. It can be concluded that seasonal variations should be incorporated into interpretation of biomonitoring studies in mussels.  相似文献   
69.
OBJECTIVE: To evaluate the diagnostic effectiveness of cytometric features of DNA microdensitometry, karyometry (nuclear morphometry) and maturation and their combinations in separating benign nevi from malignant melanomas. STUDY DESIGN: Tumor cells were measured from each of the superficial, middle and deep zones of 81 melanocytic lesions using video image analysis for nuclear DNA content, chromatin compactness, and nuclear size and shape variables. There were 27 banal compound melanocytic nevi, 20 dysplastic compound nevi, 10 Spitz nevi and 24 malignant melanomas (MM). Maturation of cells with depth into the dermis was also studied by comparing cells from superficial to deep zones. RESULTS: MM showed distinct characteristics of DNA microdensitometry, karyometry and maturation as compared to all groups of benign nevi. There were overall close correlations between nuclear DNA content variables and nuclear size parameters in the total group of 81 lesions. However, there were fewer significant correlations between the various indices in the group of melanomas alone. Using multivariate discriminant analysis, up to 97% of the lesions could be correctly separated as benign or malignant by a combination of five key microdensitometric, karyometric and maturation parameters. CONCLUSION: DNA microdensitometry, karyometry and maturation parameters have independent abilities in identifying individual malignant melanomas. Coevaluation of various cytometric features and maturation profiles offers better diagnostic ability in separating benign nevi from MM.  相似文献   
70.
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