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1.
Salivaricin CRL 1328 is a heat-stable bacteriocin produced by Lactobacillus salivarius CRL 1328, a strain isolated from healthy human vagina, with potential applications for preventing urogenital infections. The objective of this study was to characterize the locus responsible for salivaricin CRL 1328 production and its mechanism of action against Enterococcus faecalis MP97 as the sensitive strain. Oligonucleotides were designed based on sequences of antimicrobial peptides previously described in the literature. The salivaricin CRL 1328 cluster was identified, sequenced and analyzed. This cluster was similar to the previously described ABP118 which codified for a two-peptide bacteriocin. The putative mature peptides of salivaricin CRL 1328, Salα and Salβ were chemically synthesized. These peptides did not show bacteriocin activity when assayed individually. Both peptides exhibited optimal antimicrobial activity at an equimolar ratio. Spectroscopic fluorescence assays were carried out using the synthetic peptides to study the effect of salivaricin on proton motive force. This bacteriocin was shown to dissipate membrane potential and the transmembrane proton gradient, both components of proton motive force. E. faecalis MP97 cells treated with salivaricin CRL 1328 peptides were observed in transmission electron microscopy which revealed ultrastructural modifications of the cell wall.  相似文献   
2.
The receptor activity-modifying protein (RAMP)/calcitonin receptor-like (CRL) receptor heterodimer is thought to function as a receptor for either a calcitonin gene-related peptide (CGRP) (CRL receptor/RAMP1) or adrenomedullin (CRL receptor/RAMP2 or -3), depending on the RAMP isoform present. We examined the receptor specificity of adrenomedullin-induced increases in cAMP in human embryonic kidney (HEK)293 cells coexpressing human CRL receptor and human RAMP1 or RAMP2. In cells expressing CRL receptor/RAMP1, adrenomedulin-induced increases in cAMP were comparable to those induced by alpha-CGRP, and the CGRP receptor antagonist alpha-CGRP-(8-37), but not the adrenomedullin receptor antagonist adrenomedullin-(22-52), blocked the adrenomedullin-evoked responses. Cells expressing CRL receptor/RAMP2 responded more selectively to adrenomedullin; in this case, the effect was blocked by adrenomedullin-(22-52) but not by alpha-CGRP-(8-37). Real-time quantitative polymerase chain reaction confirmed that cotransfection of CRL receptor and RAMP1 had no effect on the endogenous expression of RAMP2. Thus, CRL receptor/RAMP1 likely functions as an adrenomedullin receptor as well as a CGRP receptor, which may explain why many of the actions of adrenomedullin are potently antagonized by alpha-CGRP-(8-37).  相似文献   
3.
The hippocampal formation plays a critical role in cognitive function. The developmental events that shape the hippocampal formation are continuing to be elucidated and their implications for brain function are emerging as well as applying those advances to interventions that have important possibilities for the treatment of brain dysfunction. The story told in this chapter is about the use of the in oculo transplant method to illuminate intrinsic and extrinsic features that underlie the development of the dentate gyrus and adjacent hippocampus and the role of one molecule in the hippocampus and schizophrenia. Schizophrenia, originally conceptualized as a dysfunction in dopaminergic neurotransmission, is now known to involve multiple neuronal systems. Dysfunction of hippocampal neurons is emerging as one of its signature pathological features. Basic insights into the development and function of hippocampal interneurons form the basis of a new treatment initiative for this illness. Evidence for the role of the alpha 7-nicotinic acetylcholine receptor in the development and function of these neurons in rodents has led to human trials of nicotinic agonists for cognitive dysfunction in schizophrenia and the possibility of improving hippocampal development in children at risk for schizophrenia by perinatal supplementation with choline, which can act as an alpha 7-nicotinic acetylcholine receptor agonist.  相似文献   
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5.
目的 研究泛素化酶CRL4蛋白复合体家族成员CRL4WD40重复序列结构域蛋白70(WDR70)在卵巢癌细胞中的DNA修复功能,以及卵巢癌组织中该泛素化酶基因的突变规律。方法 利用免疫荧光方法,检测CRL4骨架蛋白DDB1及WDR70基因特异性沉默的卵巢癌细胞与其对应的对照组细胞在化疗药物或放射线照射诱导产生DNA双链断裂后,组蛋白H2AX(γH2AX)及单链DNA结合蛋白32(RPA32)磷酸化灶点显示的差异;BrdU标记和染色实验检测WDR70基因对DNA复制是否存在影响,同时利用免疫组化染色检测卵巢癌组织临床病理标本及正常卵巢组织标本中的WDR70和组蛋白H2B单泛素化(uH2B)染色差异,以阐明CRL4的DNA损伤应答特征,RTPCR测定卵巢癌组织中WDR70的基因表达水平,并采用DNA测序确定WDR70突变位点。结果 免疫荧光染色结果显示,CRL4WDR70的不同蛋白亚基(DDB1、WDR70)在细胞周期检验点激活和uH2B介导的DNA末端回切过程中起着不同的作用:DDB1参与以上两个机制的调控,而WDR70只促进末端回切、RPA32在DNA断裂点的招募和同源重组修复。BrdU标记和染色结果显示WDR70基因对DNA复制并不存在影响。免疫组化结果显示,卵巢癌组织临床病理标本及正常卵巢组织标本中的WDR70和uH2B表达存在差异。RTPCR结果显示WDR70基因的全长、5′和3′转录本水平在50%的卵巢癌组织中水平减低,出现多处外显子突变位点。结论 CRL4在DNA修复过程中具有促进H2B单泛素化、促进DNA末端回切和激活细胞周期检验点等多种重要功能,是维持基因组稳定性、遏阻卵巢癌发生的重要抗癌机制。  相似文献   
6.
We present an economic evaluation of a recently completed cohort study in which 2054 seniors were screened for atrial fibrillation (AF) in 22 Canadian family practices. Using a Markov model, trial and literature data were used to project long-term outcomes and costs associated with 4 AF screening strategies for individuals aged 65 years or older: no screening, screen with 30-second radial manual pulse check (pulse check), screen with a blood pressure machine with AF detection (BP-AF), and screen with a single-lead electrocardiogram (SL-ECG). Costs and outcomes were discounted at 1.5% and the model used a lifetime horizon from a public payer perspective. Compared with no screening, screening for AF in Canadian family practice offices using pulse check or screen with a blood pressure machine with AF detection is the dominant strategy whereas screening with SL-ECG is a highly cost-effective strategy with an incremental cost per quality-adjusted life-year (QALY) gained of CAD$4788. When different screening strategies were compared, screening with pulse check had the lowest expected costs ($202) and screening with SL-ECG had the highest expected costs ($222). The no-screening arm resulted in the lowest number of QALYs (8.74195) whereas pulse check and SL-ECG resulted in the highest expected QALYs (8.74362). Probabilistic analysis confirmed that pulse check had the highest probability of being cost-effective (63%) assuming a willingness to pay of $50,000 per QALY gained. Screening for AF in seniors during routine appointments with Canadian family physicians is a cost-effective strategy compared with no screening. Screening with a pulse check is likely to be the most cost-effective strategy.  相似文献   
7.
The functional dentition of the domestic sheep lacks all upper incisors and the upper canines. Nevertheless, occurrence of a dental lamina and rudimental tooth primordia had been described in the upper incisor region of the sheep. The aim of this study was to describe temporo-spatial pattern of origin and regression of these rudimental tooth primordia by light microscopy, computer-aided three-dimensional reconstruction and morphometry of the dental epithelium. Transient existence of a dental lamina in the upper incisor region of the sheep and three epithelial thickenings on its deep mesenchymal margin has been observed at day of ontogeny (DO) 48-53. They could not been identified as full-value tooth primordia, because they did not induce differentiation of tooth mesenchyme, but they could represent last remnants of functional upper incisors in early ancestors of ruminants. Additionally, a large rudimental upper canine primordium near the sutura maxilloincisiva occurred at DO43, reached early cap stage at DO52 and started to regress at DO53. Thus, our findings showed a discrepancy between the embryonic and adult dental pattern in the sheep. Similar molecular mechanisms as described for diastemal tooth rudiments in rodents could be involved during regression of rudimental tooth primordia in the upper incisor region of the sheep.  相似文献   
8.
The ontogeny of the neurotensin neuron system in the lower brain stem of the rat was investigated by means of indirect immunofluorescent method. Neurotensin-like immunoreactivity-containing cells first appear in the primordium of the n. tractus solitarii, n. tractus spinalis nervi trigemini, reticular formation just medial to the latter nucleus, n. reticularis parvocellularis, n. laterodorsalis tegmenti, and midbrain reticular formation of the fetus at gestational day 17. At gestional day 18, neurotensin-immunoreactive cells newly appear in the n. raphe dorsalis. Between gestational day 19 and postnatal day 7, the animals show a remarkable increase in number of immunoreactive cells and fibers in various lower brain stem areas except for n. tractus spinalis nervi trigemini and n. tractus solitarii. Moreover, during this stage, neurotensin-immunoreactive cells located in the n. prepositus hypoglossi and n. vestibularis lateralis appear for the first time at birth and postnatal day 5, respectively. Since postnatal day 7, although the majority of immunoreactive cells located in the lower brain stem decrease in number as the rats grow, immunoreactive cells in the n. tractus spinalis nervi trigemini, on the contrary, increase in number from after birth until postnatal day 10, and maintain more or less their immunoreactivity even in the adult rat. In addition, neurotensin-immunoreactive cells in the nucleus of the solitary tract increase in number during the fetal period, reach the maximum content at postnatal day 7-10, and maintain their immunoreactivity even in the adult rats. Thus, the present study demonstrated that neurotensin-like immunoreactive structures appear at a very early ontogenetical stage, suggesting that neurotensin plays an important role in the development of the lower brain stem of the rat. In addition, the present study further showed that neurotensin-immuno-reactivity shows various fluctuations during the ontogeny, suggesting multiple functions of neurotensin in the central nervous system.  相似文献   
9.
外周血淋巴细胞CR1分子定量测定及其临床应用   总被引:1,自引:0,他引:1  
目的 建立一种定量测定外周血淋巴细胞补体受体1型(PBLCR1)分子的敏感性、特异性、重复性良好的实验方法,并探讨其临床意义.方法 常规法分离PBL,并定量包被于V型板中,依次加入抗CR1单克隆抗体、碱性磷酸酶(AP)标记二抗及可溶性底物显色,移显色液于比色孔,405nm比色,计算吸光度值(A).结果 正常人PBLCR1分子表达数量A值平均值为(1.26±0.25),显著高于肝细胞癌(0.72±0.20)、肝硬化(0.69±0.19)、肾病综合征(0.58±0.17)及系统性红斑狼疮(0.47±0.15)患者(P<0.01);SLE患者PBLCR1分子表达的数量显著低于其他疾病组(P<0.01),差异有统计学意义.结论 本方法具有良好的敏感性、特异性和重复性;CR1分子的数量表达可分为高、中、低3种形式;正常人为高表达;HCC和LC患者以中、低表达为主;肾病综合征和SLE患者表达显著降低.PBLCR1分子定量测定,对免疫相关性疾病的辅助诊断与治疗效果的评价具有重要的临床意义.  相似文献   
10.
Background: Cardiovascular disease is the leading cause of worldwide morbidity and mortality. Several studies have demonstrated that specific probiotics affect the host’s metabolism and may influence the cardiovascular disease risk. Objectives: The aim of this study was to investigate the influence of an isoflavone-supplemented soy product fermented with Enterococcus faecium CRL 183 and Lactobacillus helveticus 416 on cardiovascular risk markers in moderately hypercholesterolemic subjects. Design: Randomized placebo-controlled double-blind trial Setting: São Paulo State University in Araraquara, SP, Brazil. Participants: 49 male healthy men with total cholesterol (TC) >5.17 mmol/L and <6.21 mmol/L Intervention: The volunteers have consumed 200 mL of the probiotic soy product (group SP-1010 CFU/day), isoflavone-supplemented probiotic soy product (group ISP–probiotic plus 50 mg of total isoflavones/100 g) or unfermented soy product (group USP-placebo) for 42 days in a randomized, double-blind study. Main outcome measures: Lipid profile and additional cardiovascular biomarkers were analyzed on days 0, 30 and 42. Urine samples (24 h) were collected at baseline and at the end of the experiment so as to determine the isoflavones profile. Results: After 42 days, the ISP consumption led to improved total cholesterol, non-HDL-C (LDL + IDL + VLDL cholesterol fractions) and electronegative LDL concentrations (reduction of 13.8%, 14.7% and 24.2%, respectively, p < 0.05). The ISP and SP have prevented the reduction of HDL-C level after 42 days. The C-reactive protein and fibrinogen levels were not improved. The equol production by the ISP group subjects was inversely correlated with electronegative LDL concentration. Conclusions: The results suggest that a regular consumption of this probiotic soy product, supplemented with isoflavones, could contribute to reducing the risk of cardiovascular diseases in moderately hypercholesterolemic men, through the an improvement in lipid profile and antioxidant properties.  相似文献   
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