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31.
A Rapid and Simple PCR-based Method for Analysis of Transgenic Fish using a Restricted Amount of Fin Tissue 总被引:3,自引:0,他引:3
The protocol described in this paper offers a simple and rapid method for PCR analysis of transgenes using a restricted amount of fin tissue from small-sized transgenic fish. A simple preparation of fin lysate using a buffer containing a low concentration of an ionic detergent, SDS (0.01%), followed by neutralization with a second buffer containing higher concentrations of non-ionic detergents NP40 (2%) and Tween 20 (2%) consistently provides a reliable quantity of high-quality DNA template for PCR amplification of transgenes. Based on this protocol, transgenic fish can be clearly distinguished from non-transgenic fish using PCR in a rapid and reproducible manner. Tedious DNA purifications are avoided while fidelity of amplification and efficient identification of transgenic fish are maintained. 相似文献
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Cho KI Lee JW Kim KS Lee EJ Suh JG Lee HJ Kim HT Hong SH Chung WH Chang KT Hyun BH Oh YS Ryoo ZY 《Comparative medicine》2003,53(6):642-648
Circling mice manifest profound deafness, head-tossing, and bi-directional circling behavior, which they inherit in autosomal recessive manner. Histologic examination of the inner ear reveals abnormalities of the region around the organ of Corti, spiral ganglion neurons, and outer hair cells. A genetic linkage map was constructed for an intraspecific backcross between cir and C57BL/6J mice. The cir gene was mapped to a region between D9Mit116/D9Mit15 and D9Mit38 on mouse chromosome (Chr) 9. Estimated distances between cir and D9Mit116, and between cir and D9Mit38 were 0.70 +/- 0.40 and 0.23 +/- 0.23 cM, respectively. Order of the markers was defined as follows: centromere - D9Mit182 - D9Mit51/D9Mit79/D9Mit310 - D9Mit212/D184 - D9Mit116/D9Mit15 - cir - D9Mit38 - D9Mit20 - D9Mit243 - D9Mit16 - D9Mit55/D9Mit125 - D9Mit281. On the basis of genetic mapping, we constructed a yeast artificial chromosome (YAC) contig across the cir region. The cir gene is located between the lactotransferrin (ltf) and microtubule-associated protein (map4) genes. The distal portion of mouse Chr 9 encompassing the cir region is homologous with human chromosome 3p21, which contains the Deafness, form B: Autosomal Recessive Deafness (DFNB6) locus. Therefore, the circling mouse is a potential animal model for DFNB6 deafness in humans. 相似文献
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Ivanova M Tzvetanova E Jetcheva V Kilár F 《Journal of biochemical and biophysical methods》2002,53(1-3):141-150
Capillary zone electrophoresis and high-resolution agarose gel electrophoresis were compared to detect protein components in serum and cerebrospinal fluid of patients. Both electrophoretic methods proved to be useful for detection of protein abnormalities (e.g., mono- and oligoclonal bands) in biological fluids, but capillary electrophoresis offered several important advantages, such as sample application without preliminary concentration, lack of staining procedures, and on-line evaluation of patterns. Furthermore, capillary electrophoresis exhibits shorter analysis time and high resolution with low baseline noise. The results were proven to be powerful in diagnosis and monitoring of dyscrasias in routine laboratory practice. 相似文献
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Rezeli M Világhy B Kilár F Kanyó K Török B Török A 《Journal of biochemical and biophysical methods》2002,53(1-3):151-156
Human ovarian follicular fluids and sera obtained from women pre-treated for in vitro fertilization (IVF) were investigated by capillary zone electrophoresis. Comparison of the matching physiological liquids showed substantial differences in the electrophoretic patterns. Significant decrease in the alpha(1)- and gamma-fractions of follicular fluids of every woman were observed, whereas other fractions of the samples did not show such alterations. Since follicular fluid is a product of both, secretion by granulosa cells and diffusion from the theca capillaries, we can assume that the forced production of follicular fluid upon hormone stimulation (with gonadotropin releasing hormone (GnRH), follicle stimulating hormone (FSH) and corionic gonadotroph hormone (hCG)) may play role in the uneven presence of the proteins. 相似文献
36.
A renewed interest in the development of the inner ear has provided more data on the fate and cell lineage relationships of the tissues making up this complex structure. The inner ear develops from a simple ectodermal thickening of the head called the otic placode, which undergoes a great deal of growth and differentiation to form a multichambered nonsensory epithelium that houses the six to nine sensory organs of the inner ear. Despite a large number of studies examining otic development, there have been surprisingly few fate maps generated. The published fate maps encompass four species and range from preotic to otocyst stages. Although some of these studies were consistent with a compartment and boundary model, other studies reveal extensive cell mixing during development. Cell lineage studies have been done in fewer species. At the single cell level the resulting clones in both chicks and frogs appear somewhat restricted in terms of distribution. We conclude that up until late placode stages there are no clear lineage restriction boundaries, meaning that cells seem to mix extensively at these early stages. At late placode stages, when the otic cup has formed, there are at least two boundaries located dorsally in the forming otocyst but none ventrally. These conclusions are consistent with all the fate maps and reconciles the chick and frog data. These results suggest that genes involved in patterning the inner ear may have dynamic and complex expression patterns. 相似文献
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Z Hubálek V Cerny T Mittermayer J Kilík J Halouzka Z Juricová I Kuhn V Bárdos 《Journal of hygiene, epidemiology, microbiology, and immunology》1986,30(1):87-98
The serosurveys conducted in the Silica plateau area of the Slovak karst region revealed the presence of specific neutralizing antibody against tick-borne encephalitis (TBE) virus in 18% of local inhabitants (33 examined, mostly goats and sheep farmers), 54% of goats (26 examined), 18% of sheep (120 examined) and 13% of cattle (60 examined), against Lipovník (LIP) virus in 30% of inhabitants, 88% of goats, 55% of sheep and 45% of cattle, and against Bhanja (BHA) virus in 27% of inhabitants, 46% of goats, 29% of sheep and 23% of cattle. The results of hemagglutination-inhibition tests with TBE and BHA antigens were analogous. A detailed analysis of these serologic data points to a recent enhancement of the circulation of LIP and BHA viruses and to a very low TBE virus activity in this natural focus of arboviral infections. The immunological surveys of the 32 former "Roznava disease" patients, conducted 25 years after an extensive epidemic of a TBE virus infection that originated in Roznava in 1951, revealed the presence of neutralizing (and also hemagglutination-inhibiting) antibodies against TBE virus in as many as 78% of cases. Antibodies against LIP and BHA viruses were also detectable in the sera of 16% and 9%, respectively, of these individuals. Populations of the ectoparasites examined for the presence of arbovirus comprised 231 Ixodes ricinus, 806 Dermacentor marginatus and 204 Haemaphysalis punctata ticks and 117 specimens of the louse-flies Melophagus ovinus. Two strains of arbivirus that were antigenically related to Lipovník and Tribec viruses belonging to a group of Kemerovo viruses were isolated from male and female I. ricinus ticks collected from cattle. 相似文献
40.
Distinguishing characteristics of hyperrecombinogenic RecA protein from Pseudomonas aeruginosa acting in Escherichia coli 下载免费PDF全文
In Escherichia coli, a relatively low frequency of recombination exchanges (FRE) is predetermined by the activity of RecA protein, as modulated by a complex regulatory program involving both autoregulation and other factors. The RecA protein of Pseudomonas aeruginosa (RecA(Pa)) exhibits a more robust recombinase activity than its E. coli counterpart (RecA(Ec)). Low-level expression of RecA(Pa) in E. coli cells results in hyperrecombination (an increase of FRE) even in the presence of RecA(Ec). This genetic effect is supported by the biochemical finding that the RecA(Pa) protein is more efficient in filament formation than RecA K72R, a mutant protein with RecA(Ec)-like DNA-binding ability. Expression of RecA(Pa) also partially suppresses the effects of recF, recO, and recR mutations. In concordance with the latter, RecA(Pa) filaments initiate recombination equally from both the 5' and 3' ends. Besides, these filaments exhibit more resistance to disassembly from the 5' ends that makes the ends potentially appropriate for initiation of strand exchange. These comparative genetic and biochemical characteristics reveal that multiple levels are used by bacteria for a programmed regulation of their recombination activities. 相似文献