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81.
Triploid origin of the gibel carp as revealed by 5S rDNA localization and chromosome painting 总被引:2,自引:0,他引:2
5S ribosomal DNA (rDNA) was isolated and sequenced from the gibel carp Carassius auratus gibelio with 162 chromosomes and crucian carp Carassius auratus with 100 chromosomes, and fluorescent probes for chromosome localization were prepared to ascertain the ploidy origin and
evolutionary relationship between the two species. Using fluorescence in-situ hybridization (FISH), major 5S rDNA signals were localized to the short arms of three subtelocentric chromosomes in the gibel
carp and to the short arms of two subtelocentrics in the crucian carp. In addition, some minor signals were detected on other
chromosomes of both species. Simultaneously, six chromosomes were microdissected from the gibel carp metaphase spreads using
glass needles, and the isolated chromosomes were amplified in vitro by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR). Significantly, when the DOP-PCR-generated probes
prepared from each single chromosome were hybridized, three same-sized chromosomes were painted in each gibel carp metaphase,
whereas only two painted chromosomes were observed in each crucian carp metaphase spread. The data indicate that gibel carp
is of triploid origin in comparison with diploid crucian carp. 相似文献
82.
83.
当男性在社会生产中的地位日趋重要,并且人们开始将生殖与男性相联系时,男阴便受到崇拜,古人常以鸟作为男性生殖器的像征,这或许是因为鸟头和颈具有与男性生殖器有相似的伸缩功能的缘故, 相似文献
84.
85.
Two groups of proteins are present in the vitreous: collagen and non-collagen, deriving probably from the blood serum. The authors examined the proteolytic activity against haemoglobin in the course of some ocular pathological conditions. It was demonstrated that the vitreous digests haemoglobin in the acid division of pH (optimum--3.0-4.5) with various activity dependent on the pathological condition of the eye. 相似文献
86.
Administration of kainic acid (15 mg/kg, i.p.) or pentetrazole (75 mg/kg, i.p.) to rats evoked recurrent limbic or tonic-clonic seizures, respectively. Radioimmunoassay showed that the level of alpha-neoendorphin (prodynorphin-derived peptide) in the hippocampus was decreased after 3 h (by c. 60%) and 72 h (by c. 40%), but was not changed after 24 h following kainic acid administration. The basal release of alpha-neoendorphin from hippocampal slices of kainic acid-treated rats was decreased after 3, 24 and 72 h following the drug injection by c. 50%. The K(+)-stimulated release was decreased after 3 and 24 h (by c. 300 and 200%, respectively) and was back to the control level after 72 h. An in situ hybridization study showed that kainic acid strongly enhanced the prodynorphin messenger RNA levels in the dentate gyrus after 3 and 24 h (by c. 200%), whereas after 72 h it tended to decrease. Twenty four hours after pentetrazole injection the hippocampal level of alpha-neoendorphin was elevated (by c. 33%) and remained unchanged after 3 and 72 h. No significant changes in the basal or K(+)-stimulated alpha-neoendorphin release from hippocampal slices of pentetrazole-treated rats were found at any time points measured. Three and 24 h after pentetrazole administration the level of prodynorphin mRNA in the dentate gyrus was slightly decreased (by c. 30%), but was back to the control values after 72 h. Hence seizure-related changes in hippocampal prodynorphin neuron activity seem to depend on the experimental model of epilepsy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
The authors present the results of investigations performed in 28 right-handed, normally seeing persons divided into 2 groups: 15 of them were in productive age and 13 in older age. The authors compared the dynamics of the behaviour of the visual functions in dependence on the age of the subjects and the stay in the glow and sodium light. No adverse influence of the sodium light on the hand localization could be detected, instead it seems that it negatively influenced the selective reaction in older productive persons in the sense of an increased number of faults. 相似文献
88.
J. F. Wang M. Wang J. L. Ma L. G. Jiao X. Y. Zhou J. E. Lindberg 《Transboundary and Emerging Diseases》2006,53(3):113-118
Ten multiparous lactating sows were used to investigate whether intramammary infusion of lipopolysaccharides (LPS; Escherichia coli 0111:B4; 2.0 μg/kg of body weight) would affect the circulating concentrations of Ca, P, 25‐hydroxyvitamin D (25‐OHD), tumour necrosis factor‐α (TNF‐α), interleukin‐6 (IL‐6) and cortisol. The sows were randomly allotted to either control group (control) or LPS‐treated group with five individuals per group and were infused with either physiological saline solution or LPS solution. The rectal temperature and udder quarter appearance were recorded at 0 (just before infusion), 1, 3, 7, 12 or 24 h after infusion. Blood samples were taken at 0, 1, 3, 7, 12 or 24 h after infusion. Before infusion, the rectal temperatures of all sows were below 39.2°C. At 3 and 7 h after infusion, the sows in the LPS group had a rectal temperature over 39.4°C. At 24 h after infusion, the rectal temperatures returned to pre‐infusion levels. Serum Ca and P concentrations in the LPS group decreased (P < 0.05) after LPS infusion compared with the control group at 1 h after infusion. No significant differences (P > 0.05) in the concentrations of 25‐OHD were observed between groups control and LPS at any sampling time. Increased (P < 0.01) concentrations of serum TNF‐α, IL‐6 and cortisol were observed in the LPS group compared with the control group at 3 and 7 h after infusion respectively. In conclusion, the elevation of serum concentrations of TNF‐α, IL‐6 and cortisol and the alterations of circulating concentrations of Ca and P following LPS infusion indicate that the immune system has been activated and immune activation may affect macromineral homeostatic regulation, which might have important implications for metabolic health of lactating sows. Lowered serum Ca and P following immune activation also shows a causative mechanism whereby immune activation increases the risk of secondary disorders such as mastitis‐metritis‐agalactia syndrome. However, immune activation did not affect circulating concentrations of vitamin D metabolites. 相似文献
89.
B. B. Y. Ma A. Oza E. Eisenhauer† G. Stanimir‡ M. Carey§ W. Chapman¶ E. Latta¶ K. Sidhu J. Powers† W. Walsh† A. Fyles 《International journal of gynecological cancer》2004,14(4):650-658
A multicenter phase II trial was conducted to define the activity of letrozole in postmenopausal women with recurrent or advanced endometrial carcinoma, who had no more than one prior line of progestins and never had chemotherapy (except adjuvant). Archival paraffin-embedded tumor samples were retrieved to determine the expression level of estrogen (ER) and progesterone receptor (PgR), p53, HER-2, bcl-2 and PTEN protein, and phosphorylation status of protein kinase B (PKB/Akt). Thirty-two eligible patients were treated with letrozole at 2.5 mg daily continuously, of whom 10 (31%) had prior progestins. Of the 28 patients evaluated for response, one complete and two partial responses were noted; overall response was 9.4% (95% confidence interval 2-25%). Eleven patients had stable disease for a median duration of 6.7 months (range 3.7-19.3 months). Amongst 22 patients who had tumor blocks available, the proportion showing positive expression of the following markers includes: PgR (86%), ER (86%), PTEN (82%), phosphorylated PKB/Akt (59%), bcl-2 (45%), p53 (32%), and HER-2 (0%). None of these markers correlated with response to letrozole or disease progression. In conclusion, letrozole is well tolerated but has little overall activity in this cohort of women with endometrial cancer. 相似文献
90.
The spectrometric analysis of extracts from tobacco and tobacco smoke revealed the presence of pentobarbital in the analyzed substances. Tobacco samples and tobacco smoke were extracted with chloroform, determinations were performed with the Perkin-Elmer Autosystem XL system, on a Turbo Mass spectrometer. Subject to analysis were 4 cigarette brands manufactured in Poland and raw, unprocessed tobacco. The presence of pentobarbital in the analyzed samples was confirmed by the analysis of the mass spectrum of the substance, as well as by comparison of retention time with standard of pentobarbital. The determined pentobarbital concentrations in tobacco amounted to 3-6 microg/cigarette, and in tobacco smoke they were approximately 45% lower. In case of tobacco extracts it can with high probability be excluded that pentobarbital is synthesized during chromatographical analysis. The presence of pentobarbital in tobacco is thus beyond question. 相似文献