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排序方式: 共有990条查询结果,搜索用时 15 毫秒
11.
12.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡 总被引:3,自引:1,他引:3
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。 相似文献
13.
Human acute leukemia cell line with the t(4;11) chromosomal rearrangement exhibits B lineage and monocytic characteristics 总被引:18,自引:8,他引:18
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia. 相似文献
14.
Templeton AW; Johnson JA; Anderson WH; Cook LT; Dwyer SJ d; Preston DF; Lee KR; Rosenthal SJ; Batnitzky S; Levine E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use. 相似文献
15.
Daniels DL; Czervionke LF; Millen SJ; Haberkamp TJ; Meyer GA; Hendrix LE; Mark LP; Williams AL; Haughton VM 《Radiology》1989,171(3):807-809
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding. 相似文献
16.
17.
von der Mohlen MA; van Deventer SJ; Levi M; van den Ende B; Wedel NI; Nelson BJ; Friedmann N; ten Cate JW 《Blood》1995,85(12):3437-3443
A recombinant endotoxin-neutralizing protein, rBPI23, was shown to partially prevent endotoxin-induced activation of the fibrinolytic and coagulation systems in experimental endotoxemia in humans. In a placebo- controlled, blinded crossover study, eight volunteers were challenged twice with an intravenous bolus injection of endotoxin (40 EU/kg of body weight) and concurrently received either rBPI23 (1 mg/kg) or placebo (human serum albumin, 0.2 mg/kg). rBPI23 treatment significantly lowered the endotoxin-induced fibrinolytic response, ie, reduced the release of tissue-type plasminogen activator, urokinase- type plasminogen activator, plasminogen activator inhibitor antigen, and complex formation of plasmin alpha 2-antiplasmin (P = .0078 for each). Plasminogen activator inhibitor activity was also reduced, but not significantly according to the Hochberg method (P = .0304). The endotoxin-induced activation of the procoagulant state as reflected by increase in F1 + 2 fragments and TAT complexes was blunted by rBPI23 infusion (P = .0391 [not significant according to the Hochberg method] and .0078, respectively). These results indicate that rBPI23 is capable of reducing both the activation of the fibrinolytic and the coagulation systems after low-dose endotoxin infusion in humans. 相似文献
18.
M.A. Radtke C. Lee-Seifert SJ. Rustenbach I. Schäfer Prof. Dr. M. Augustin 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》2009,60(5):414-419
Background
Products containing dexpanthenol are used to treat irritated and inflamed skin. So far there is a lack of data for the evidence of patient-relevant benefits.Objective
Assessment of the patient-relevant benefit of ointments containing dexpanthenol in the self-medicated therapy of irritated skin.Methods
Prospective, observational study in a network of 392 pharmacies. Consecutive recruitment of n=1,886 patients with symptoms of irritated skin, including non-inflammatory intervals of atopic eczema, other xerotic skin conditions and impairment of skin barrier. The patient-relevant benefit was ascertained prior to and 7–10 days after treatment through the patient-benefit index (PBI).Results
The PBI showed that 91.5% of the patients experienced a relevant benefit from treatment. 94.7% directly indicated to have had achieved successful therapeutic results. All symptoms of irritated skin (e.g. xerosis, erythema, desquamation) significantly improved (p≤0,001). The subjective response was independent of age, gender and underlying skin disease.Conclusion
High patient-relevant benefits were observed in the treatment of irritated skin with dexpanthenol ointment. 相似文献19.
20.
Sarah A Stuart Paul Butler Marcus R Munafò David J Nutt Emma SJ Robinson 《Neuropsychopharmacology》2015,40(9):2165-2174
The biochemical targets for antidepressants are relatively well established, but we lack a clear understanding of how actions at these proteins translate to clinical benefits. This study used a novel rodent assay to investigate how different antidepressant drugs act to modify affective biases that have been implicated in depression. In this bowl-digging task, rats encounter two equal value learning experiences on separate days (one during an affective manipulation and the other during control conditions). This induces an affective bias that is quantified using a preference test in which both digging substrates are presented together and the individual rats’ choices recorded. The assay can be used to measure affective biases associated with learning (when the treatment is given at the time of the experience) or examine the modification of previously acquired biases (when the treatment is administered before the preference test). The rapid-onset antidepressant ketamine, but not the delayed-onset antidepressant, venlafaxine, attenuated the previously acquired FG7142-induced negative bias following systemic administration. Venlafaxine but not ketamine induced a positive bias when administered before learning. We then used local drug infusions and excitotoxic lesions to localize the effects of ketamine to the medial prefrontal cortex and venlafaxine to the amygdala. Using a modified protocol we also showed that positive and negative biases amplified further when the numbers of substrate–reinforcer associations are increased. We propose that this pattern of results could explain the delayed onset of action of venlafaxine and the rapid onset of action but lack of long-term efficacy seen with ketamine. 相似文献