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Testicular torsion is a urological emergency referred to as 'acute scrotum', because inappropriate treatment can lead to male subfertility and infertility. A possible cause of testicular damage is the ischaemia-reperfusion (I/R) injury attributed to oxygen free radicals. L-carnitine, a vitamin-like antioxidant, plays a pivotal role in the maturation of spermatozoa within the reproductive tract. The aim of the present paper was to determine the protective effect of L-carnitine on testicular I/R-induced injury. Thirty-two male rats were divided into 4 groups (n = 8). Testicular torsion was created by rotating the right testis 720 degrees in a clockwise direction. Group 1: sham-operated control; group 2: ischaemia; group 3: I/R; group 4: ischaemia-L-carnitine treatment-reperfusion group. L-carnitine (500 mg kg(-1), intraperitoneally) was administered before 30 min of detorsion in Group 4. After torsion (5 h) and detorsion (5 h), bilateral orchidectomy was performed. The malondialdehyde (MDA) level was evaluated in testes. Histopathologically, Johnsen's spermatogenesis criteria and mean seminiferous tubule diameter (MSTD) measurements were used. Testicular MDA levels were higher in the torsion group compared to the sham-control group (p < 0.05). Detorsion (reperfusion) caused a further increase in MDA levels (p < 0.05). Pretreatment with L-carnitine prevented a further increase in MDA levels (p < 0.05). Histologically, torsion caused some separation among germinal cells in the seminiferous tubules, which became much more prominent in the I/R group but was attenuated with L-carnitine pretreatment. In conclusion, L-carnitine pretreatment may have a protective effect in experimental testicular torsion-detorsion model in rats by its well-known antioxidant potential.  相似文献   
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Heat stress compromises production, fertility, and health of dairy cattle. One mitigation strategy is to select individuals that are genetically resistant to heat stress. Most of the negative effects of heat stress on animal performance are a consequence of either physiological adaptations to regulate body temperature or adverse consequences of failure to regulate body temperature. Thus, selection for regulation of body temperature during heat stress could increase thermotolerance. The objective was to perform a genome-wide association study (GWAS) for rectal temperature (RT) during heat stress in lactating Holstein cows and identify SNPs associated with genes that have large effects on RT. Records on afternoon RT where the temperature-humidity index was ≥78.2 were obtained from 4,447 cows sired by 220 bulls, resulting in 1,440 useable genotypes from the Illumina BovineSNP50 BeadChip with 39,759 SNP. For GWAS, 2, 3, 4, 5, and 10 adjacent SNP were averaged to identify consensus genomic regions associated with RT. The largest proportion of SNP variance (0.07 to 0.44%) was explained by markers flanking the region between 28,877,547 and 28,907,154 bp on Bos taurus autosome (BTA) 24. That region is flanked by U1 (28,822,883 to 28,823,043) and NCAD (28,992,666 to 29,241,119). In addition, the SNP at 58,500,249 bp on BTA 16 explained 0.08% and 0.11% of the SNP variance for 2- and 3-SNP analyses, respectively. That contig includes SNORA19, RFWD2 and SCARNA3. Other SNPs associated with RT were located on BTA 16 (close to CEP170 and PLD5), BTA 5 (near SLCO1C1 and PDE3A), BTA 4 (near KBTBD2 and LSM5), and BTA 26 (located in GOT1, a gene implicated in protection from cellular stress). In conclusion, there are QTL for RT in heat-stressed dairy cattle. These SNPs could prove useful in genetic selection and for identification of genes involved in physiological responses to heat stress.  相似文献   
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Telomerase is one of the key enzymes responsible for the proliferative immortality of the majority of cancer cells. We recently introduced a new telomerase inhibitor, a 13-mer oligonucleotide N3' --> P5'-thio-phosphoramidate lipid conjugate, designated as GRN163L. This compound inhibits telomerase activity in various tumor cell lines with IC(50) values of 3-300 nM without any cellular uptake enhancers. GRN163L demonstrated potent and sequence specific anti-cancer activity in vivo in multiple animal models. This compound was able to significantly affect not only the growth of primary tumors, but also the spread and proliferation of metastases. GRN163L is currently in Phase I and Phase I/II clinical studies in patients with solid tumors and CLL, respectively.  相似文献   
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Aim: This study was carried out to determine if there is any association between plasminogen activator inhibitor type-1 (PAI-1) gene 4G/5G polymorphism and plasma PAI-1 enzyme activity in acute stroke patients. Methods: In this study, 333 genomic DNAs (from 253 acute stroke patients and 80 healthy subjects) were analyzed. Genomic DNAs were prepared from peripheral blood using a saline method. These DNAs were amplified by PCR method using primers specific for 4G and 5G alleles. PCR products were separated by 2% agarose gel electrophoresis and visualized by a charge coupled device (CCD) camera. PAI-1 enzyme activities were measured by ELISA method. The results were evaluated statistically with Student's t-test, chi(2)-test, one-way analysis of variance, and stepwise regression analysis. Results: In this study, frequency of PAI-1 gene 4G5G genotype was found to be low both in patients and controls. PAI-1 enzyme activities were significantly increased in acute stroke patients compared to controls. Although PAI-1 gene 4G5G genotype frequencies were low, the patients carrying this allele had highest plasma PAI-1 enzyme activity; likewise, although PAI-1 gene 4G4G genotype frequencies were high, the patients carrying this allele had lowest plasma PAI-1 enzyme activities. Homocysteine levels had a positive effect of 65% on plasma PAI-1 enzyme activities. Conclusion: Consequently, in this study, we may assert that PAI-1 gene, 4G4G and 5G5G genotypes, PAI-1 activity, and homocysteine level determination are significant criteria for identifying patients who are likely to develop stroke; on the other hand, a direct relation does not exist between gene polymorphism and enzyme activity.  相似文献   
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Schizophrenia is a chronic and neuropsychiatric disease that affects about 0.5–1% of the world’s population. An increase in dopamine and dopamine D2 receptor (DRD2) gene products has been well described in schizophrenic patients. Several groups have studied the relationship between dopaminergic hyperactivity and cellular communications have obtained discordant results. Studies searching for the relationship between the schizophrenia and DRD2 gene have gained more interest. Our objective was to determine the relationships among schizophrenic symptoms in schizophrenia subtypes and severity of symptoms in terms of DRD2 gene −141C Insertion/Deletion [Ins/Del; I/D] polymorphism by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) assay method. Genomic DNA was prepared from peripheral blood by using salt extraction method. After amplification of genomic DNA, PCR products were digested with BstNI restriction enzyme for the detection of DRD2 gene −141C Ins/Del polymorphism in 73 schizophrenic patients and 60 healthy control subjects. The allelic frequencies of the DRD2 gene −141C Ins/Del polymorphism in case and control groups were 79.5 and 77.5% for I allele; 20.5 and 22.5% for D allele respectively. There was no significant difference in frequencies of genotypes and alleles between the two groups. In schizophrenic and control subjects, there were no significant relationship in severity of the disease and schizophrenia types among the −141C Ins/Del genotypes and alleles.  相似文献   
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The importance of microbial natural compounds in drug research is increasing every year and they are used to prevent or treat a variety of diseases. Hypomyces chrysospermus is a cosmopolitan parasite of many Boletaceae members. Since not much work has been conducted to date, this study is undertaken to explore the anticancer effect, including the antiproliferative and antimetastatic activity of Hypomyces chrysospermus. The aim of this study is to determine the antiproliferative and antimetastatic activity of Hypomyces chrysospermus ethyl acetate extract, having antioxidant activity, against A549, Caco2, MCF-7 human cancer and CCD-19 Lu and CCD 841 CoN healthy human cell lines. Firstly, cytotoxic activity was determined by the WST-1 assay. After cell proliferations and anti-metastatic effects were investigated by a real-time cell analysis system (RTCA-DP) and IC50 concentrations were calculated for each cell line. In addition, the expression levels of Apaf-1, TNF and NF-kB mRNA in cancer cells were investigated with RealTime-PCR. The ethyl acetate extract of Hypomyces chrysospermus presented anticancer activities including antiproliferative and antimetastatic effects. Hypomyces chrysospermus as a source of biologically active metabolites can be used as an important resource in the development of new anticancer effective agents.

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Bladder carcinoma is the second most common genitourinary malignancy. Treatment options for bladder cancer include surgery, combined with chemotherapy, radiation, and/or immunotherapy. The adjuvant chemotherapy and immunotherapy regimen have been widely used in locally invasive as well as metastatic disease. The evaluation of new active agents with improved tolerability has been the focus of investigations over the past decade with minimal overall improvements in outcomes. Telomerase activity has been found in approximately 85-90% of all human tumors, but not in the majority of adjacent normal tissues. This suggests that telomerase may be an attractive target for the development of novel anticancer therapeutic agents. GRN163L is a lipid conjugated oligonucleotide N3' --> P5' thio-phosphoramidate, and is a potent telomerase RNA (hTR) template antagonist. In the present study, we show that the telomerase activity of T24-luc bladder cancer cells is inhibited by 1 microM GRN163L within 24 h of incubation. After two weeks of exposure to GRN163L, T24-luc cells became "clustered" whereas non-cancerous normal human uroepithelial cells were not morphologically affected. Moreover, in vitro GRN163L treated T24-luc bladder cancer cells entered G(0)/G(1) arrest following 2 weeks of continuous exposure and stopped dividing. Mismatch control compound had no effect on normal bladder epithelial cells or T24-luc cells. Additionally, a new generation of thio-phosphoramidate oligonucleotides were designed and tested in T24-luc cells and compared with GRN163L. The obtained results warrant further in vivo evaluation of GRN163L as a potential treatment for bladder cancer.  相似文献   
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