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1.
Interstitial cystitis/bladder pain syndrome (IC/BPS) and vulvodynia are chronic pain syndromes that appear to be intertwined from the perspectives of embryology, pathology and epidemiology. These associations may account for similar responses to various therapies. 相似文献
2.
K562/ADM耐药细胞株的建立及其生物学特性的初步观察 总被引:9,自引:2,他引:7
我们建立的K562/ADM耐药细胞株,在ADM浓度为2.4μg/m1(4.46μM)中已稳定培养3.5个月,传了30—35代,K562/ADM亦具有多药耐受件(Multidrug Resistance,MDR)的特点,对ADM、VCR、AT—1258和DDP的耐受性分别为K562的114.7、94.0、13.3和7.4倍,但对5—FU不产生交叉耐药。K562和K562/ADM的倍增时间分别为19.2h和52.8h,集落生成率分别为37.5%和11.1%,K562染色体数为34—68,中位数为56;K562/MDM染色体数为32—90,中位数为50,K562/ADM可做为耐药机理和克服耐药措施研究的极好模型。 相似文献
3.
Flecainide 总被引:1,自引:0,他引:1
RODNEY H. FALK M.D. RICHARD I. FOGEL M.D. 《Journal of cardiovascular electrophysiology》1994,5(11):964-981
Flecainide. Flecainide is a Class IC antiarrhythmic agent whose primary electrophysiologic effect is a slowing of conduction in a wide range of cardiac tissues. It is well absorbed and effective in suppressing isolated premature ventricular contractions (PVCs) or nonsustained ventricular arrhythmia but has only a modest efficacy when electrophysiologic testing is used as an endpoint. Us adverse effect on mortality in the CAST trial suggested a propensity to proarrhythmia-a phenomenon to which the Class IC agents appear particularly prone. Despite the applicability of the CAST study only to patients with a prior myocardial infarction, there has been a shift away from flecainide in ventricular arrhythmia, but the low noncardiac side effect profile of the agent allows for its continued use in a wide variety of supraventricular arrhythmias. ( J Cardiovasc Electrophysiol, Vol. 5, pp. 964–981. November 1994 ) 相似文献
4.
Class I molecules of the major histocompatibility complex bind peptides derived from cytosolic proteins and display them on the cell surface. This function alerts cytotoxic T cells to the presence of intracellular pathogens. Class I molecule assembly requires the association of the heavy chain with β2-microglobulin, accompanied by peptide loading via specific transporters. This study localizes where these assembly steps take place, using monoclonal antibodies recognizing class I molecules in different assembly states to analyze subcellular fractions of the early secretory pathway. The distribution of peptide-loaded class I molecules was more localized than the distribution of the total pool of class I molecules in the early secretory pathway. Loaded molecules colocalized with the peptide transporter, free heavy chains, and the chaperone calnexin in high density rough endoplasmic reticulum (RER) membranes. These data suggest that subunit assembly and peptide acquisition occur at the same intracellular site. Class I molecules also localized to less dense subfractions of the early secretory pathway, which contained comparatively less peptide-loaded molecules than the high density RER fractions, at steady state. Following a 15 °C temperature block, class I molecules accumulated in these less dense membrane fractions, indicating that these fractions represent the intermediate compartment where empty class I molecules are trapped in mutant cells. In the presence of cycloheximide, a pool of class I molecules recycling to the RER was detected, suggesting empty molecules recycle to acquire peptide. 相似文献
5.
6.
Autoradiography and anterograde horseradish peroxidase transport were used to examine retinocollicular projections in normal hamsters and in animals subjected to ablation of the ipsilateral, posterior neocortex at 1, 3, 6, 10 or 120 days of age. The crossed retinotectal projections of all groups were quite similar. There did, however, appear to be a slight increase in the density of the projection to the lower portion of the stratum griseum superficiale in the neonatally brain-damaged hamsters.The uncrossed pathway, on the other hand, was quite abnormal in the neonatally lesioned animals. In normals, the ipsilateral retinocollicular projection consisted almost entirely of a series of patches along the stratum yriseum superficiale-stratum opticum border in the rostral one-third of the colliculus. Only a few axons from the ipsilateral eye were observed in the caudal two-thirds of the tectum and these could only be visualized when horseradish peroxidase was used as the tracer. In all of the neonatally brain-damaged hamsters both autoradiography and horseradish peroxidase tracing demonstrated that the ipsilateral retina densely innervated the entire rostrocaudal extent of the colliculus.Retrograde tracing experiments demonstrated that the portion of the temporal retina which gave rise to the uncrossed retinocollicular projection in the normal hamsters was also the source of the expanded projection in the neonatally brain-damaged animals; and, further, that the numbers and areal distributions of ipsilaterally projecting retinal and retinocollicular ganglion cells were similar in the two groups.These findings suggest that, at least in the hamster, normal inputs from the two eyes may not be a sufficient condition for the development of the largely complementary pattern of collicular innervation by the two retinae. 相似文献
7.
Rosenson-Schloss RS Vitolo JL Moghe PV 《Medical & biological engineering & computing》1999,37(2):257-263
Leukocytes adherent to the surfaces of both vascular biomaterials and normal blood vessels experience blood flow induced shear stress. The goal of the reported studies was to investigate the effect of fluid flow on the morphology, phagocytic function and stress response induction in adherent immune cells. Shear approximating arterial, venous and intermediate levels were applied onto glass-adherent IC21 macrophages in a temperature-controlled parallel plate flow system. The results indicate that fluid flow induces a shear-dependent physiological stress response in adherent macrophages and that significant morphological changes accompany macrophage responses to shear stress. In addition, arterial flow conditions induce not only significant cell polarisation, but also enhanced phagocytic ingestion in glass-adherent IC21 macrophages. These findings suggest that blood flow induced shear stress may not only be consequent to adherent leukocyte activation, but may also be integral to the regulation of adherent leukocyte behaviour in vivo. 相似文献
8.
The application of Ion chromatographic method for bioavailability and stability test of iron preparations 总被引:1,自引:0,他引:1
Young -Ok Kim Hye -Joo Chung Hak -Soo Kong Don -Woong Choi Dae -Hyun Cho 《Archives of pharmacal research》1999,22(3):288-293
Postabsorptive serum iron level was determined after oral administration of the compounds to human. In serum and whole blood, Fe3+ was measured by ion chromatography (IC) using a pyridine-2,6-dicarboxylic acid (PDCA) as an eluent. The serum sample solutions were pretreated with I N HCI and 50% TCA. The whole blood sample solutions were treated with 3 N HCI for 30 min at 125 degrees C. The limit of detection (LOD) of the IC technique is 0.2 microM for Fe2- and 0.1 microM for Fe3+. The area under concentration (AUC) can be obtained by the above analytical condition. In addition, to compare the stability of Fe2+ to that of Fe3+ in pharmaceutical preparations, accelerated stability test was carried out. After storing the samples under 40 degrees C, 75%RH in light-resistant container for various time intervals, the contents of iron of different valencies were determined separately by the IC technique and the change and/or the interchange of among those iron species in preparations was investigated. Iron raw materials are stable, but Fe2+ in Fe3+ source materials was slightly converted to Fe3+ by oxidation. Fe2+ in Fe3+ source raw materials and Fe3+ in Fe2+ raw materials are determined as impurities. Therefore, IC technique is found to be an appropriate method for comparative evaluation of dissimilar bioavailability of Fe2+ and Fe3+, stability of Fe2+ and Fe3+ raw materials and preparations. 相似文献
9.
目的 探讨HBV感染者HBV—DNA阳性血清HBeAg阴性的影响因素。方法 采用ms—PCR及ELISA方法分别检测HBV感染者血清中A-1896及HBeAg/IC。结果 29例HBV—DNA阳性、HBeAg阴性血清标本,HBeAg/IC阳性17例(58.7%),单一A-1896者3例(10.3%),HBeAg/IC及A-1896共存2饲(6.9%)。结论 HBeAg/IC形成是HBV—DNA阳性血清HBeAg阴性的主要原因,而非A-1896。 相似文献
10.