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91.
颅面联合入路切除颅眶鼻沟通瘤   总被引:4,自引:0,他引:4  
本文报告了颅面联合入路成功切除颅眶鼻沟通瘤5例,包括上颌窦腺鳞癌及胚胎型横纹肌肉瘤各1例,嗅神经母细胞瘤2例,分化好的软骨肉瘤1例。重点讨论了手术方法,眼球保留及颅底修复等问题。  相似文献   
92.
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial.  相似文献   
93.
Synthetic fragment of human interferon-2α (124th–138th amino acid residue, laboratory code 2438) inhibits the growth of B lymphocytes (Daudi cell line) in a dose-dependent manner. Radiolabeled peptide 2438 binds to specific receptors on the cell surface and competes with interferon-2α for the common binding sites. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 446–448, April, 1997  相似文献   
94.
The Boyden chamber assay is widely used for in vitro measurement of the invasive capacity of cells. However, results can be affected significantly if certain precautions are not taken. Using the Boyden chamber assay we investigated in vitro the invasive potential of a variety of human gynecological tumor cell lines to degrade and migrate through the artificial basement membrane matrix Matrigel. However, in the absence of this Matrigel layer large differences were observed in the ability of cells to adhere to, migrate through and attach to the lower side of the filter membranes. These differences were influenced by cell density, degree of directional locomotion, and the size of the filter pores. To adjust for these influences (which are not directly correlated to the capacity of cells to traverse the Matrigel layer), invasion results were corrected for the ability of cells to migrate through the filter membrane. In addition, the invasion of MDA-MB-231 cells was used as an internal standard to compensate for variations in the Matrigel layer between different experiments. Overall, in our experimental set up, the five human breast cancer cell lines were the most invasive (mean invasion ± SEM relative to MDA-MB-231 invasion: 104.7 ± 6.1%), the five human ovarian cancer cell lines the least invasive (60.2 ± 2.2%) and the six human endometrial cancer cell lines showed an intermediate capacity (79.1 ± 3.5%). In conclusion, the Boyden chamber assay can be used reliably for studying the invasive potential of cells in vitro, if the ability of the cells to migrate through the filter is taken into account, and a reference cell line is included to enable comparison of the data obtained from independently performed experiments on different cell lines.  相似文献   
95.
研究了V235E、V235L、V411三个结肠肿瘤细胞株的细胞凋亡现象。DNA电泳分析和AO/EB荧光染色形态学检查表明,这三个肿瘤细胞株均存在自发性凋亡。提示肿瘤细胞,包括恶变的癌细胞仍可保留与增殖相对立的凋亡过程。肿瘤细胞存在自发性细胞凋亡的观察,有助于更好地认识肿瘤的发生和发展过程。此外,这些细胞株也为进一步研究细胞凋亡的诱导及其调控提供了有用的细胞模型。  相似文献   
96.
Androgen receptor synthesis and modification were studied in the human LNCaP cell line. Immunoblotting with a specific polyclonal antibody showed that the androgen receptor migrated as a closely spaced 110–112 kDa doublet on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels. Most of the receptor protein is present in the higher molecular mass form. Pulse labelling experiments with [35S]methionine showed that the androgen receptor is synthesized as a single 110 kDa protein which is rapidly converted to a 112 kDa protein. Alkaline phosphatase treatment of cytosols from [35S]methionine pulse labelled cells caused a gradual elimination of the 112 kDa isoform with a concomitant increase of the 110 kDa isoform. This indicates that the observed 110 to 112 kDa upshift of the newly synthesized androgen receptor reflects receptor phosphorylation. Both isoforms can bind hormone and can undergo a hormone dependent transformation to a tight nuclear binding form, indicating that the 110 to 112 kDa conversion is not an obligatory step for hormone binding or receptor transformation.  相似文献   
97.
A spontaneous lymphoid thymus tumor was discovered in a male Xenopus of the MHC ff genotype. The tumor cell can be transplanted in histocompatible larval ff hosts, but not in ff adults unless irradiated (3000 rad). The tumor is rejected by allogeneic hosts. The tumor cells express neither markers of the B-cell lineage nor MHC encoded molecules; they express only markers of the T-cell lineage. Its lymphoid population is clonal as revealed by the existence of a stable rearrangement pattern of the immunoglobulin genes. Cell lines growing continuously in vitro have been derived from the tumor.  相似文献   
98.
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity. Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers. On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes may also play an important role in damage to nerve fibers.  相似文献   
99.
Summary According to recent data the incidence of second tumors in cured hereditary unilateral retinoblastoma patients is 20% within 10 years, 50% after 20 years and rises to 90% after 30 years. Nonhereditary unilateral retinoblastoma patients have not been regarded as susceptible for second nonocular tumors so far. A case is reported of such a patient having developed a second presacral retroperitoneal tumor after successful treatment of a nonhereditary unilateral retinoblastoma group V without intracranial extension or pulmonary metastases. Consequently all (hereditary and non-hereditary) retinoblastoma patients should receive at least quarterly intensive follow-up examinations after primary ophthalmologic treatment.  相似文献   
100.
Splanchnic ischaemia and its role in multiple organ failure   总被引:3,自引:0,他引:3  
Multiple organ failure remains the leading cause of death in the intensive care unit. Increasing numbers of investigators have focused their attention on the role of gastrointestinal tract in the pathogenesis of this syndrome. Their data indicate that inadequate gut perfusion leads to a measurable imbalance between oxygen delivery and the needs of the tissues, i.e., ischaemia. Gut ischaemia of sufficient duration impairs gastrointestinal tract barrier function, facilitating the passage of enteric bacterial endotoxin into the circulation. It has been hypothesized that production of tumor necrosis factor α, and other biologic mediators by endotoxin–stimulated macrophages, triggers a generalized and uncontrolled inflammatory response that ultimately leads to multiple organ failure.
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed.  相似文献   
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