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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
3.
The diagnosis of a primary fibromyalgia syndrome (PFS) which is supported mainly by clinical-anamnestic elements is, in many cases, finally established in the generalized stadium of the disease. It would be generally desirable to discover potentially endangered patients and to define "risk groups". During this study a case-by-case retrospective analysis of all available data sources (specialist's and hospital reports) has been conducted on 61 PFS-patients of a general practice. A further clarification diagnosis resulted in 75% of the cases suffering from general exhaustion. In over 50% of the examined patients diagnostic details referred to chronic lumbar and cervical spine syndromes. It is well possible that chronic cervical and lumbar spine as well as psychovegetative exhaustion syndromes predispose the generation of a PFS under consideration of a corresponding personality profile and other factors or it may even be a disease by itself. In every general practice the respective tender points of suspected patients should be examined and they should be questioned as to the basic symptoms of this disease.  相似文献   
4.
Hydrolysis of peptides within lumen of small intestine   总被引:2,自引:0,他引:2  
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5.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation  相似文献   
6.
Differential pattern of DNA-aneuploidy in human malignancies   总被引:5,自引:0,他引:5  
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
Previous studies demonstrated that the formamidine pesticide chlordimeform (CDM) reversibly inhibited prostaglandin biosynthesis and prevented the late (PG-mediated) phase of carrageenin-induced hind paw edema. This study emphasizes antagonism by CDM of the early (5HT and histamine-mediated) phase of carrageenin edema. CDM and cyproheptadine both antagonized paw edema induced by albumin (5HT and histamine-mediated) and by the direct injection of 5HT and histamine, whereas aspirin and the PG antagonist, SC-19220, were ineffective. As expected, cyproheptadine selectively reduced the early phase, whereas aspirin and SC-19220 selectively reduced the late phase of carrageenin-induced edema. These results are thus consistent with earlier studies demonstrating PG mediation of the late phase of carrageenin edema, and 5HT and histamine mediation of albumin edema and the early phase of carrageenin edema. In addition, they indicate that CDM possesses multiple acute anti-inflammatory, actions not exhibited by aspirin, by SC-19220 or by cyproheptadine alone.  相似文献   
8.
Forty schizophrenic patients, 40 non-schizophrenic patients, and 40 normal subjects were given 60 each alternating 1000- and 2000-Hz, 1-second tones at 60 dB. Half of each sample, the Press Group (PG), had to press a pedal to the high (low) target tone, ignoring the nontarget tone. The other half, the Nonpress Groups (NPGs), were given no reason to attend. Skin conductance response (SCR), finger pulse volume (FPV), and electroencephalographic (EEG) activity were recorded. NPG schizophrenic subjects were more often nonresponsive in both SCR and FPV than other samples, but less often responsive in EEG only when a 20 percent criterion of alpha blockade was used. Schizophrenic subjects showed greater consistency of OR nonresponsiveness in SCR and FPV, and nonsignificantly greater consistency in criterion alpha block, pointing to a deficit in orienting response (OR) rather than in peripheral response. When the targeted signal was given, schizophrenic subjects showed the same response as other groups in all systems. This was not due to an indiscriminate increase in reactivity, since response increase centered on the targeted signal itself in all groups. As the target signal was repeated, autonomic OR in schizophrenics declined sharply so that they again became underresponsive. Thus, OR "normalization" achieved by targeting significant signals is restricted to relatively early responsiveness. The rapid decline in autonomic OR may help explain differences in schizophrenic subjects between P300 and autonomic ORs to significant stimuli. Schizophrenic subjects were no different from controls in bilateral SCR or FPV asymmetry, but displayed less frequent criterion alpha blockade and reduced background alpha power in the left hemisphere. Each system showed a different pattern of bilateral asymmetry, reflecting complex, not well understood relations among these responses. This was further emphasized by the fact that skin conductance level (SCL) incremented over trials in PG subjects, reflecting sustained activation, while EEG background showed an increase in slower wave power, consistent with reports of increased drowsiness. The only drug effect seen was a lowering of SCL. Neuroleptics were associated with a flexible inhibitory control of SCL, permitting normal-like increment when circumstances required. Depressed patients' data suggested they might show heightened OR nonresponsiveness to innocuous stimuli which might not be subject to "normalization" by manipulation of stimulus significance; hence OR deficit might still differentiate schizophrenic from depressive patients.  相似文献   
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10.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
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