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61.
A novel macrocyclic spermine alkaloid incasine C' (1), along with a known compound incasine C (2), were isolated from the whole plants of Incarvillea sinensis, and their structures were elucidated on the basis of chemical and spectroscopic evidence.  相似文献   
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OBJECTIVES: The polyamines putrescine, spermidine, and spermine, play an important role in cell proliferation, differentiation, and transformation. The aim of this study is to correlate the polyamines with apoptosis and clinico-pathologic events in Egyptian breast cancer patients. METHODS: PUT, SPD, and SPN were investigated using thin layer chromatography (TLC) and apoptosis in fresh frozen tissue specimens obtained from 40 patients suffering from breast cancer, as well as 20 patients with benign breast lesions. RESULTS: The levels of PUT, SPD, and SPN were higher in breast cancer tissues than in benign breast lesions (p < 0.001). Polyamines were correlated well with apoptosis. Moreover, PUT was an independent prognostic factor for relapse. Also, SPD and SPN correlated significantly with early tumor grades. ROC curves were used to choose the best cut-off values for polyamines (70, 135, and 290 mmol/g tissue) for PUT, SPD, and SPN, respectively. At these cut-off values, the sensitivities were (75%, 60%, and 70%), and the specificities were (80%, 95%, and 95%) for PUT, SPD, and SPN, respectively. CONCLUSION: Polyamines may be used as additional markers for detection of malignant transformation in breast tissue. Moreover, because of their ability to induce apoptosis in malignant tissues, polyamines are suitable targets for therapeutic intervention that is specifically directed to induce apoptosis.  相似文献   
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Der Einfluß von Prolaktin und Spermin auf den Zinkgehalt menschlicher Spermatozoen
In einer experimentellen Studie wurde der Einfluß von physiologischen Dosen o-Prolaktin (0–10 ng) und Spermin (0–2 mg) auf den intracellularen Zinkgehalt menschlicher Spermatozoen untersucht. Es ergab sich eine negative Korrelation des Zinkgehaltes zu der Prolaktin- und Spermin-Konzentration.  相似文献   
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高压液相色谱分析测定正常及癌症病人尿中的多胺   总被引:1,自引:0,他引:1  
本文用高压液相色谱法(HPLC)分析测定74例肿瘤患者及60例正常人尿中多胺,其结果表明:肿瘤病人尿中腐胺、精眯、精胺及3种多胺总平均值分别为正常人的2.2、4.9、11.2、3.6倍,都有非常明显的统计学差异(P<0.005),特别是肺癌和食管癌更为显著(P<0.001)。证明该方法可用作诊断癌瘤和观察疗效的生化指标。  相似文献   
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Natural polyamines have been proposed to induce histamine release from mast cells through a direct interaction with G proteins. Alternatively, the polyamine binding site of ionotropic N-methyl-d-aspartate (NMDA) receptors has been suggested as a target for spermine on mast cells. We reexamined both hypotheses. Incubation of rat peritoneal mast cells with spermine resulted in a concentration-dependent histamine release (EC50 270 μM). Incubation with NMDA receptor agonists, glutamate or NMDA, associated to the co-agonist glycine, did not induce secretion. Western blot experiments did not reveal NMDA R1, R2a, R2b or R2c subunit expression in rat peritoneal mast cell membranes. The NMDA receptor antagonist at the glycine site, L-689,560, did not modify, at relevant concentrations, the spermine-induced secretion. The NMDA receptor antagonists, ifenprodil and LY 235959, and the NMDA channel blocker, MK801, slightly inhibited, at high concentrations, the secretory effect of spermine. The polyamine arcaine, an antagonist of the NMDA receptor polyamine binding site, induced histamine secretion (EC50 350 μM). Both spermine- and arcaine-induced effects were independent upon extracellular calcium and were largely inhibited by treatment of mast cells with pertussis toxin or benzalkonium chloride. The response to spermine and arcaine was prevented by the hydrolysis of sialic acid residues of the cell surface by neuraminidase, and was restored by permeabilization of the plasma membrane with streptolysine-O, indicating that polyamines act intracellularly. These results confirm the involvement of pertussis toxin-sensitive G proteins in the secretory effect of polyamines and demonstrate the absence of NMDA receptors on rat peritoneal mast cells. Nonselective effects of some NMDA receptor ligands on mast cells cannot be excluded. Received: 28 December 1998 / Accepted: 19 March 1999  相似文献   
69.
Summary A new enzymatic method for the quantitation of spermine in human semen, based on the specific reaction of barley seedling polyamine oxidase with spermine, is described. Small amounts of human semen were incubated with the polyamine oxidase; hydrogen peroxide formed in the oxidase reaction was measured photometrically by coupling 4-aminoantipyrine with N-ethyl-N-(3-methylphenyl)-N-acetylethylenediamine in the presence of peroxidase. The detection limit of spermine of this method was about 10 nmol per tube. The mean level of spermine in human semen was 2.41 mol/ml; the levels in vaginal fluid, saliva, serum, and urine were below the detectable limit by this procedure.  相似文献   
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Administration of polyamines into the central nervous system results in tissue damage, possibly through the excitotoxic actions of the NMDA receptor. Direct injection of 100 nmol of spermine into the rat striatum produced a lesion equivalent to approximately 50% of the striatum. Analysis of the DNA in this region revealed the distinct ladder-like pattern of degradation often associated with apoptosis. This DNA fragmentation was confirmed in vivo using terminal deoxynucleotidyl-transferase-mediated biotinylated deoxyuridine triphosphate nick end labelling (TUNEL). The morphology of the TUNEL-positive cells showed marked differences at the needle tract when compared with cells in damaged areas away from the needle tract, suggesting a differential mechanism of cell death in these two regions. The patterns of p53, c-Fos and c-Jun protein expression were determined using immunohistochemistry. The number of p53-immunoreactive cells increased up to 14 h and returned to basal levels by 24 h. c-Fos protein expression transiently increased, peaking at 8 h after injection. c-Jun exhibited a protracted pattern of expression, remaining elevated up to 24 h. p53 protein expression was colocalised with TUNEL staining in areas away from the needle tract, but not in cells at the needle tract, suggesting once again a differential mechanism of cell death. At 14 h, c-Fos and c-Jun were not colocalised with TUNEL staining, suggesting that they are either not involved with the cell death process or that the time course of protein expression and the onset of DNA fragmentation do not overlap. This work represents the first characterisation of processes associated with cell death induced by spermine in vivo.  相似文献   
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