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1.
Dexrazoxane has been approved to treat anthracycline-induced cardiomyopathy and extravasation. However, the effect of dexrazoxane on epirubicin-induced genetic alterations in germ cells has not yet been reported. Thus, the aim of this study was to determine whether dexrazoxane modulates epirubicin-induced genetic damage in the germ cells of male mice. Our results show that dexrazoxane was not genotoxic at the tested doses. Furthermore, it protected mouse germ cells against epirubicin-induced genetic alterations as detected by the reduction in disomic and diploid sperm, spermatogonial chromosomal aberrations, and abnormal sperm heads. The attenuating effect of dexrazoxane was greater at higher dose, indicating a dose-dependent effect. Moreover, sperm motility and count were ameliorated by dexrazoxane pretreatment. Epirubicin induced marked biochemical changes characteristic of oxidative DNA damage including elevated 8-hydroxy-2ʹ-deoxyguanosine levels and reduction in reduced glutathione. Pretreatment of mice with dexrazoxane before epirubicin challenge restored these altered endpoints. We conclude that dexrazoxane may efficiently mitigate the epirubicin insult in male germ cells, and prevent the enhanced risk of abnormal reproductive outcomes and associated health risks. Thus, pretreating patients with dexrazoxane prior to epirubicin may efficiently preserve not only sperm quality but also prevent the transmission of genetic damage to future generations.  相似文献   
2.
Gold nanoparticles (GNPs) are among the ideal nano-sized materials for medical applications such as imaging and drug delivery. Considering the significance of recent reports on acute phase induction of inflammatory mediators by GNPs, we studied the effect of GNPs on proinflammatory cytokines gene expression in mouse brain. Group 1 served as control whereas groups 2–4 were given only one intraperitoneal dose of 5, 20 and 50?nm GNPs, respectively and sacrificed after 24?h. The animals in groups 5–7 also received the same treatment but sacrificed after 7?days. Groups 8–10 received two injections of GNPs (5, 20 and 50?nm, respectively), first at the beginning of study and second on day 6, and sacrificed on day 7. Total RNA was extracted from the cerebral tissue and analyzed for the gene expressions of IL-1β, IL-6 and TNF-α. A single injection of 5?nm diameter GNPs significantly increased the mRNA expression of IL-1β and IL-6 in mouse brain on day 7, which was not augmented by the second dose of the same GNPs. Larger size GNPs (20?nm and 50?nm) did not cause any significant change in the expression of proinflammatory cytokines in mouse brain. In conclusion, systemic administration of small sized GNPs (5?nm) induced a proinflammatory cascade in mouse brain indicating a crucial role of GNPs size on immune response. It is important to use the right sized GNPs in order to avoid an acute phase inflammatory response that could be cytotoxic or interfere with the bioavailability of nanomaterials.  相似文献   
3.
This study investigates the amphisbaenian species skull which includes cranium, lower jaw and hyoid apparatus. The medial dorsal bones comprise the premaxilla, nasal, frontal and parietal. The premaxilla carries a large medial tooth and two lateral ones. The nasals are paired bones and separated by longitudinal suture. Bones of circumorbital series are frontal, orbitosphenoid and maxilla. The occipital ring consists of basioccipital, supraoccipital and exooccipital. Supraoccipital and basioccipital are single bones while the exo-occipitals are paired. The bones of the palate comprise premaxilla, maxilla, septomaxilla, palatine, pterygoid, ectopterygoid, basisphenoid, parasphenoid, orbitosphenoid and laterosphenoid. Prevomer and pterygoid teeth are absent. Palatine represent by two separate bones. The temporal bones are clearly visible. The lower jaw consists of the dentary, articular, coronoid, supra-angular, angular and splenial. The hyoid apparatus is represented by a Y-shaped structure. The mandible is long and is suspended from the braincase via relatively short quadrate. There is an extensive contact between the long angular and the large triangular coronoid. Thus inter-mandibular joint is bridged completely by the angular and consequently, the lower jaws are relatively rigid and kinetic. The maxillae are suspended from the braincase largely by ligaments and muscles rather than through bony articulation. In conclusion, the skull shape affects feeding strategy in Diplometopon zarudnyi. The prey is ingested and transported via a rapid maxillary raking mechanism.  相似文献   
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Studies on the effect of ninhydrin in the normal gastric mucosa and against the ethanol induced gastric injury were undertaken in rats in view of the presence of a carbonyl function as well as hydroxyl groups in its chemical structure. In spite of its potentials to generate hydroxyl radicals, it is deemed to possess antioxidant property by virtue of its electrophilic nature. Recent studies have shown gastro-protection to mediate through a reaction between the electrophilic compounds and sulfhydryl groups of the mucosa. Hence it was found worthwhile to evaluate the interaction between the oxidant and antioxidant functions in the structure of the same compound. The effects of ninhydrin pretreatment on gastric mucosal injuries caused by 80% ethanol, 25% NaCl and 0.2M NaOH were investigated in rats. The gastric tissue in ethanol-treated rats was analyzed for different histopathological lesions. In addition, the effects on ethanol-induced changes in the gastric levels of proteins, nucleic acids, non-protein sulfhydryl (NP-SH) and malondialdehyde (MDA) were also evaluated. Ninhydrin, as such, failed to induce any significant changes in normal gastric mucosa, while its pretreatment at oral doses of 5, 10 and 20 mg/kg was found to provide a dose-dependent protection against the ulcers induced by ethanol, NaOH and NaCl. The results of histopathological evaluation revealed a protective effect of ninhydrin on congestion, hemorrhage, edema, erosions and necrosis caused by ethanol. Furthermore, the pretreatment afforded a dose-dependent inhibition of the ethanol-induced depletion of proteins, nucleic acids, NP-SH and increase of MDA in the gastric tissue. The results obtained clearly demonstrate the anti-ulcerogenic activity of ninhydrin. The exact mechanism of action is not known. However, the carbonyl function in ninhydrin appears to achieve antioxidant balance and protect the gastric mucosa from the ethanol-induced gastric injury. Further studies are warranted to investigate the toxicity and detailed mechanism of action of this potent compound before any clinical trials, especially at the effective lower doses.  相似文献   
6.
AIMS: The goal of this study was to monitor the quantitative and qualitative bacterial flora in the intestine of hybrid tilapia in fresh fish and fish kept in frozen storage conditions for 1 year. METHODS AND RESULTS: Quantitative and qualitative analyses of the bacterial flora associated with the intestine of hybrid tilapia (Oreochromis niloticus x Oreochromis aureus) in fresh fish and fish kept in frozen storage conditions for 1 year were carried out. In fresh and frozen fish, aerobic plate count (APC) ranged from 1.6 +/- 1.2 x 10(8) to 1.5 +/- 0.9 x 10(5) CFU g(-1) in the intestine of tilapia collected from pond 1, 8.7 +/- 2.3 x 10(7) to 6.5 +/- 3.8 x 10(4) CFU g(-1) in the intestine of tilapia from pond 2, and 1.9 +/- 2.9 x 10(8) to 6.2 +/- 2.8 x 10(4) CFU g(-1) in the intestine of tilapia from pond 3. APC for all the groups of fish decreased c. 2-log cycles after 1 months frozen storage; thereafter, counts slowly declined during frozen storage for 1 year. Altogether, 16 bacterial genera were identified: Gram-negative rods (67%) dominated. Both in fresh and frozen conditions, four bacterial species viz. Shewanella putrefaciens, Corynebacterium urealyticum, Aeromonas hydrophila and Flavobacterium sp. were always present, with a prevalence of 10% in most cases. Shewanella putrefaciens was the most dominant organism (15% of the total isolates) throughout the studied period. During frozen storage some of the bacteria were not recovered, but most of the bacteria survived after prolonged freezing. CONCLUSIONS: This study describes the aerobic heterotrophic microflora found in the intestine of fresh and frozen tilapia. The unique aspect of this study concerns the data revealing the micro-organisms, which are viable after prolonged freezing. Contamination of edible portions of fish could originate from gastrointestinal sources. SIGNIFICANCE AND IMPACT OF THE STUDY: The present results may enhance knowledge in controlling the storage life of fish, and fish product quality. Bacterial activity is by far the most important factor influencing fish quality, so bacterial numbers can be used as an index of quality. Storage of frozen tilapia without evisceration could be avoided.  相似文献   
7.
Gemcitabine (2',2'-difluoro-2'-deoxycytidine; dFdCyd) is one of the anti-metabolites drugs that target DNA replication. We evaluated dFdCyd cytotoxicity and its radiosensitizing ability in human breast cancer cell lines, MCF-7 (wild-type p53) and MDA-MB-231 (mutant-type p53) along with normal mammary epithelial cell line (MCF-12) for comparison. Radiosensitivity and cytotoxicity were measured by the clonogenic survival assays. DNA DSBs was studied by Pulse Field Gel Electrophoresis (PFGE) and cell cycle distribution was analyzed by flow cytometry. MDA-MB-231 cells were the most sensitive to the cytotoxicity of dFdCyd (IC(50) 5 nM) then MCF-7 (IC(50) 10nM), whereas MCF-12 cells were the most resistant to the cytotoxicity of dFdCyd (IC(50) 70 nM). MCF-12 and MCF-7 cell lines did not show any radiosensitization to dFdCyd, whereas the MDA-MB-231 cells showed significantly increased radioresistant to dFdCyd at equimolar concentration (p=0.002) and at IC(50) concentration (p<0.001). The DNA double strand breaks (DSBs) repair showed that dFdCyd neither increases DNA DSBs nor decreases the rate of their repair in MCF-12 and MCF-7 cell lines, while the same treatment in MDA-MB-231 cell line led to decrease the rate of DSBs or increase the rate of DNA repair (p=0.034). Therefore, dFdCyd is a cytotoxic agent, especially in the cancer cells irrespective of having wild-type or mutated p53 protein, but it is not effective as radiosensitizer in the cell lines used in this study. dFdCyd combined with radiation reduces the efficacy of chemo-radiotherapy in p53 mutated cells. Therefore, p53-mutated cancer could be a counter-indication for radiation-gemcitabine combined treatment.  相似文献   
8.
Insertion/deletion (I/D) polymorphism, of a 287-bp Alu repetitive sequence in intron 16 of the angiotensin-converting enzyme (ACE) gene has been shown to be associated with different types of diseases and has been widely investigated in different populations with different ethnic origins. Various reports were published suggesting inter-ethnic variations in the frequency of allelic forms of the ACE gene. The goal of this study was to test the distribution of alleles and the different genotypes of ACE (I/D) polymorphism in Bahraini subjects and compare the results with those obtained from other population studies. The Bahraini population is an Arabic peninsula population with a high prevalence of T2DM and hypertension. A total of 560 unrelated Bahraini individuals were recruited in this study and the presence (insertion)/absence (deletion) (I/D) polymorphism of a 287-bp Alu1 element inside intron 16 of the ACE gene was done by PCR-based assays and the presence or absence of the genotypes were analyzed by the gel electrophoresis. The distribution of II, ID, and DD genotypes showed differences among Bahraini subjects, and the frequency of the D allele was significantly (P < 0.05) higher in the studied group. The results obtained for the D allele are consistent with those obtained from previous studies among Arabs, Africans, and Caucasians, but differs significantly (P < 0.05) from those in Japanese and Chinese, thus proving the ethnic variation in the distribution of the ACE alleles in different populations.  相似文献   
9.
Water scarcity is a major limiting factor for crop productivity in arid and semi-arid areas. Grafting elite commercial cultivars onto selected vigorous rootstocks is considered as a useful strategy to alleviate the impact of environmental stresses. This study aims to investigate the feasibility of using grafting to improve fruit yield and quality of cucumber under water stress conditions. Alosama F1 cucumber cultivar (Cucumis sativus L.) was grafted onto Affyne (Cucumis sativus L.) and Shintoza A90 (Cucurbitamaxima × C. moschata) rootstocks. Non-grafted plants were used as control. All genotypes were grown under three surface drip irrigation regimes: 50%, 75% and 100% of the crop evapotranspiration (ETc), which represent high-water stress, moderate-water stress and non-water stress conditions, respectively. Yield and fruit quality traits were analyzed and assessed. In comparison to the non-grafted plants, the best grafting treatment under water stress was Alosama F1 grafted onto Shintoza A90 rootstock. It had an overall improved yield and fruit quality under water stress owing to an increase in the total fruit yield by 27%, from 4.815 kg plant?1 in non-grafted treatment to 6.149 kg plant?1 in grafted treatment under moderate -water stress, total soluble solid contents (13%), titratable acidity (39%) and vitamin C (33%). The soil water contents were low in soil surface and increase gradually with soil depth, while salt distribution showed an adverse trend. The positive effects of grafting on plant growth, productivity, and water use efficiency support this strategy as an useful tool for improving water stress tolerance in greenhouse grown cucumber in Saudi Arabia.  相似文献   
10.
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