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1.
Blood was collected from 486 feral horses of mixed sex and age classes captured from three wild horse management areas in Nevada and Oregon from December 1985 to February 1986. Males were significantly outnumbered by females in the Flanigan area, but both sexes were represented in approximately equal numbers in the Wassuk and Beaty's Butte areas. Hematology and chemistry values averaged 16.4 +/- 0.11, 46.3 +/- 0.28, 9.9 +/- 0.07, 6.9 +/- 0.10, 47.1 +/- 0.24, 16.6 +/- 0.09, 35.2 +/- 0.09, 10.4 +/- 0.14 and 23.4 +/- 0.25 for hemoglobin (HGB), hematocrit (HCT), red blood cells (RBC), white blood cells (WBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), cortisol (F) and serum urea nitrogen (SUN), respectively. Statistically significant differences in HGB, HCT, RBC, WBC, MCV and MCH levels occurred with respect to age (P less than or equal to 0.001). Serum F levels were lower in immature animals than in either subadult or adults in all areas. Flanigan horses appeared in the poorest condition and had the lowest HGB, HCT and RBC counts while the values for Wassuk horses were significantly higher (P less than or equal to 0.001). Serum F levels were lowest in the Flanigan horses. A significantly lower (P less than or equal to 0.001) proportion of adult mares had progesterone levels consistent with pregnancy in the Flanigan horses versus those from the other two areas. These data are consistent with a subjective evaluation of the condition of the horses.  相似文献   
2.
The alpha-like globin gene cluster in rabbits contains embryonic zeta- globin genes, an adult alpha-globin gene, and theta-globin genes of undetermined function. The basic arrangement of genes, deduced from analysis of cloned DNA fragments, is 5'-zeta 0-zeta 1-alpha 1-theta 1- zeta 2-zeta 3-theta 2-3'. However, the pattern of restriction fragments containing zeta- and theta-globin genes varies among individual rabbits. Analysis of BamHI fragments of genomic DNA from 24 New Zealand white rabbits revealed eight different patterns of fragments containing zeta-globin genes. The large BamHI fragments containing genes zeta 0 and zeta 1 are polymorphic in length, whereas a 1.9-kb fragment containing the zeta 2 gene and the 3.5-kb fragment containing the zeta 3 gene do not vary in size. In contrast to this constancy in the size of the restriction fragments, the copy number of the zeta 2 and zeta 3 genes does vary among different rabbits. No length polymorphism was detected in the BamHI fragments containing the theta-globin genes, but again the copy number varies for restriction fragments containing the theta 2 gene. The alpha 1- and theta 1-globin genes are located in a nonpolymorphic 7.2-kb BamHI fragment. The combined data from hybridization with both zeta and theta probes shows that the BamHI cleavage pattern does not vary within the region 5'-alpha 1-theta 1- zeta 2-zeta 3-theta 2-3', but the pattern genomic blot-hybridization patterns for the progeny of parental rabbits with different zeta-globin gene patterns shows that the polymorphic patterns are inherited in a Mendelian fashion. Two different haplotypes have been mapped based on the genomic blot-hybridization data. The variation in the alpha-like globin gene cluster in the rabbit population results both from differences in the copy number of the duplication block containing the zeta-zeta-theta gene set and from the presence or absence of polymorphic BamHI sites.   相似文献   
3.
Direct photoaffinity labeling of tubulin with guanosine 5'-triphosphate   总被引:6,自引:0,他引:6  
J P Nath  G R Eagle  R H Himes 《Biochemistry》1985,24(6):1555-1560
Irradiation of tubulin in the presence of [3H]GTP or [3H]GDP at 254 nm led to the covalent incorporation of nucleotide into the protein. The specific nature of the labeling was shown in the following manner: with tubulin depleted of exchangeable nucleotide, the amount of labeling increased to a plateau value as the [3H]GTP concentration was increased, with saturation being reached at a ratio of approximately 1.5; the same amount of labeling was obtained with GTP/tubulin ratios of 1 and 100; [3H]GMP was not incorporated into the dimer, nor did GMP inhibit the incorporation of [3H]GTP; [3H]ATP was not incorporated; [3H]GTP incorporation did not occur into denatured tubulin or into serum albumin. When [alpha-32P]GTP was used in the irradiation experiments, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the carboxymethylated protein demonstrated that the incorporated label was associated with the beta subunit. The radiation treatment did cause changes in the tubulin molecule resulting in a decrease in assembly competence and in sulfhydryl groups, but these effects were minimized when a large excess of GTP was present during irradiation. Labeling of tubulin in the assembled state was much less than that observed in the free state.  相似文献   
4.
In order to study the relationships among mammalian alpha-globin genes, we have determined the sequence of the 3' flanking region of the human alpha 1 globin gene and have made pairwise comparisons between sequenced alpha-globin genes. The flanking regions were examined in detail because sequence matches in these regions could be interpreted with the least complication from the gene duplications and conversions that have occurred frequently in mammalian alpha-like globin gene clusters. We found good matches between the flanking regions of human alpha 1 and rabbit alpha 1, human psi alpha 1 and goat I alpha, human alpha 2 and goat II alpha, and horse alpha 1 and goat II alpha. These matches were used to align the alpha-globin genes in gene clusters from different mammals. This alignment shows that genes at equivalent positions in the gene clusters of different mammals can be functional or nonfunctional, depending on whether they corrected against a functional alpha-globin gene in recent evolutionary history. The number of alpha-globin genes (including pseudogenes) appears to differ among species, although highly divergent pseudogenes may not have been detected in all species examined. Although matching sequences could be found in interspecies comparisons of the flanking regions of alpha- globin genes, these matches are not as extensive as those found in the flanking regions of mammalian beta-like globin genes. This observation suggests that the noncoding sequences in the mammalian alpha-globin gene clusters are evolving at a faster rate than those in the beta-like globin gene clusters. The proposed faster rate of evolution fits with the poor conservation of the genetic linkage map around alpha-globin gene clusters when compared to that of the beta-like globin gene clusters. Analysis of the 3' flanking regions of alpha-globin genes has revealed a conserved sequence approximately 100-150 bp 3' to the polyadenylation site; this sequence may be involved in the expression or regulation of alpha-globin genes.   相似文献   
5.
The impact of diagnostic tests in evaluating patients with syncope   总被引:5,自引:0,他引:5  
We reviewed the charts of 100 patients admitted to the hospital for evaluation of syncope. The charts were examined with special attention given to the causes of syncope, the frequency and benefit of diagnostic tests, and the relative cost of these tests. In 39 patients no etiology for syncope was found, and another 18 were felt to have had a vasovagal episode. Twelve patients had arrhythmias as the cause for syncope. Most of the patients underwent a variety of diagnostic tests including cardiac enzyme determinations, brain scans, electroencephalograms, head CAT scans, and Holter monitoring. In most instances, these tests added little useful information to the initial history and physical exam and were done at great expense to the patient. Our data suggest that extensive neurologic testing in patients with "routine" syncope is not warranted and that the focus of hospitalization should be to rule out potentially life-threatening arrhythmias.  相似文献   
6.
A 180,388-bp contig encompassing the human retinoblastoma gene was sequenced in its entirety. Partial analysis of the sequence revealed (1) a high (A + T)/(G + C) ratio and a high density of Line-1 (L1) repeat sequences, suggesting that the locus maps to G-bands 13q14.12 or 13q14.2; (2) Alu repeats that are asymmetrically oriented over a region extending 87 kb; (3) an overabundance of non-Alu-associated poly(A) tracts 10 bp or larger oriented in the antisense rather than the sense direction (36 vs 6); (4) an Alu sequence nested within an L1 repeat, indicating that the expansion of L1 repeats predates at least some of the Alu expansions; (5) at least three newly discovered microsatellite polymorphisms, one of which was subsequently found to be identical to a polymorphism in a microsatellite-based linkage map of the human genome published by another group; and (6) the basis of previously discovered intragenic RFLPs. This sequence should enhance studies of this locus and of the organization of the human genome.  相似文献   
7.
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9.
Chan MW  Chu ES  To KF  Leung WK 《Biotechnology letters》2004,26(16):1289-1293
Although methylation-specific PCR (MSP) is a sensitive technique in the detection of DNA hypermethylation, it is not quantitative. Here we described a modified PCR protocol to quantify methylated SOCS-1 gene by real time MSP using SYBR green, which involves an additional PCR step after the 72 degrees C extension step. This modified protocol is also useful in the quantitative detection of methylated SOCS-1 gene in serum samples of gastric cancer patients.  相似文献   
10.
Huang EY  Chen CM  Tao PL 《Peptides》2004,25(4):577-583
Two potent endogenous opioid peptides, endomorphin-1 (EM-1) and -2 (EM-2), which are selective micro-opioid agonists, have been identified from bovine and human brain. These endomorphins were demonstrated to produce a potent anti-allodynic effect at spinal level. In the present study, we further investigated their supraspinal anti-allodynic effects and rewarding effects. In a neuropathic pain model (sciatic nerve crush in rats), EM-1 and -2 (15 microg, i.c.v.) both showed significant suppressive effects in the cold-water allodynia test, but EM-1 showed a longer duration than EM-2. Naltrexone (NTX; 15 microg) and naloxonazine (NLZ; 15 microg) were both able to completely block the anti-allodynic effects of EM-1 and -2. In the tests of conditioned place preference (CPP), only EM-2 at the dose of 30 microg showed significant positive rewarding effect, whereas both endomorphins did not induce any reward at the dose of 15 microg. Due to the low solubility and the undesired effect (barrel rotation of the body trunk), EM-1 was not tested for the dose of 30 microg in the CPP tests. It was also found that acute EM-2 (30 microg) administration increased dopamine turnover in the shell of nucleus accumbens in the microdialysis experiments. From these results, it may suggest that EM-1 and -2 could be better supraspinal anti-allodynic agents compared with the other opioid drugs, although they may also induce rewarding.  相似文献   
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