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51.
Primary nasal septal adenocarcinoma is a rare lesion. A sporadic case of septal adenocarcinoma in a 22 years old male is being described along with review of literature.  相似文献   
52.
Bronchial washings are used routinely in the diagnosis of lung tumors. However, unlike other tumors, the diagnosis of bronchial carcinoids on bronchial washings is difficult. We reviewed 17 cases of histologically proven bronchial carcinoids from the files of the cytology laboratory over a period of 15 yr (1986–2001). The bronchial washings and histology sections of all the cases were reviewed separately by two independent observers and the results tabulated. Two cases had inadequate bronchial washings for evaluation and were excluded from the study. A growth was identified on bronchoscopy in 13 of 15 cases. Initial cytologic diagnoses were ?adenocarcinoma/?carcinoid and suspicious of carcinoid in one case each. However, on review, tumor was identified in 10 of 13 cases initially considered to be negative. The possible reasons for a false‐negative report on initial cytology include the paucity of tumor cell fragments in the bronchial washings (5 of 12 cases showing only one to two tumor fragments) and their bland appearance, often being mistaken for benign columnar cells. This study highlights the potential pitfalls in the diagnosis of bronchial carcinoids on bronchial washings and underlines the importance of a diligent search in cases with high clinical suspicion and positive bronchoscopic findings. Diagn. Cytopathol. 2004;30:62–66. © 2004 Wiley‐Liss, Inc.  相似文献   
53.
The chronological activation of the signaling molecules following whole body gamma-irradiation was investigated in mouse liver. The activity of two kinases, tyrosine kinase and protein kinase C (PKC), was found to respond differently to gamma-irradiation. Tyrosine kinase was found to respond to much lower doses of irradiation (10 cGy), whereas PKC was found to be activated at comparatively higher doses (3 Gy). Tyrosine kinase showed a sharp activation at 30 min and then a decline to normal values at 1 h. Activation of PKC was apparent at as early as 15 min of irradiation and showed a maximal increase at 30 min. This was followed by a decline to normal values at 1 h. The response of the whole organ was found to be different from that of reported effects on a single cell. These results suggest that the data obtained from the single-cell studies would have limited application in the experiments involving the whole animal. Interruption of these signals at various steps is currently being used to manipulate tumor response to radiotherapy. In such cases, the difference in response of a single cell and a whole animal must be considered.  相似文献   
54.
Seventy six cases of neonatal tetanus were studied. There was preponderance of males. Short incubation period, short period of onset, low birth weight, presence of fever and tachycardia were associated with a poor prognosis. The cases were divided into 2 groups of 46 and 30. First group was given TIG while second group was given ATS. All other therapies were kept identical. Mortality rate in two groups was 97.5% and 96.5%. Corrected mortality due to tetanus per se was 22.5% and 28.5% (p-0.5). Fifteen cases (32.7%) and 12 cases (40%) in group A & B respectively were born to mothers who had already received one to three doses of tetanus toxoid. The potency of the vaccine should be ensured before it is administered to mothers, through proper maintenance of cold chain. It is concluded that TIG is not superior to ATS in managing moderate and severe grade cases.  相似文献   
55.
A newborn infant was referred because of low-set ears, mild downward slant of the palpebral fissues, micrognathia with higharched palate, a flat midface, small mouth, and thin upper lip with cupid bow configuration. To some extent her cry resembled that associated with cri du chat syndrome. Cytogenetic findings with G- and Q-banding alone failed to characterize precisely the complex translocations. By the chromosome in situ suppression (CISS) hybridization technique using whole chromosome specific probes, a complex 4 breakpoint rearrangement involving both arms of a single chromosome 1 with the long arms of chromosome 5 and 11 was disclosed, i.e., 46,XX, der(1),t(1;5) t(1;11) (5qter→5q31::1p31.3→1q44::11q23→11qter;5pter→5q31::1p31.3→1pter;11pter→11q23::1q44→1qter). Gene deregulation and position effect may explain the multiple anomalies in individuals with apparently balanced translocations may shed some light towards unveiling the clinical consequences associated with aberrations which are presumably balanced. © 1993 Wiley-Liss, Inc.  相似文献   
56.

Background  

Alzheimer's disease (AD) pathology shows characteristic 'plaques' rich in amyloid beta (Aβ) peptide deposits. Inflammatory process-related proteins such as pro-inflammatory cytokines have been detected in AD brain suggesting that an inflammatory immune reaction also plays a role in the pathogenesis of AD. Glial cells in culture respond to LPS and Aβ stimuli by upregulating the expression of cytokines TNF-α, IL-1β, and IL-6, and also the expression of proinflammatory genes iNOS and COX-2. We have earlier reported that LPS/Aβ stimulation-induced ceramide and ROS generation leads to iNOS expression and nitric oxide production in glial cells. The present study was undertaken to investigate the neuroprotective function of AICAR (a potent activator of AMP-activated protein kinase) in blocking the pro-oxidant/proinflammatory responses induced in primary glial cultures treated with LPS and Aβ peptide.  相似文献   
57.
The product of proto-oncogene Rel associates with a number of cellular proteins. We have studied the effect of one of them, a phosphoprotein of 40 kD (pp40), on the DNA-binding activity of the Rel protein. We demonstrate that purified pp40 not only inhibits the binding of Rel, but also NF-kappa B (p50-p65) heterocomplex to DNA. Additionally, I kappa B beta, but not I kappa B alpha, also prevented the binding of Rel to the kappa B site. I kappa B beta and pp40 are related proteins because (1) they share a number of common tryptic peptides, (2) their inhibitory effect on DNA binding can be abolished by preincubation with pp40-specific antiserum, and (3) labeled I kappa B beta can be immunoprecipitated with pp40 antibodies. pp40 is part of the Rel complex present in the cytoplasm and nuclear extracts of WEHI-231 cells. The activity of pp40 to inhibit the DNA binding of Rel and NF-kappa B is modulated by phosphorylation.  相似文献   
58.
Primary primitive neuroectodermal tumor of the cauda equina   总被引:5,自引:0,他引:5  
Primitive neuroectodermal tumors (PNETs) are aggressive neoplasms composed predominantly of undifferentiated cells that show evidence of neural differentiation. Although their classification has been controversial, PNETs are well recognized primary tumors of both central and peripheral nervous systems. PNETs must be distinguished from other round-cell tumors, including Ewing's sarcoma, lymphoma, rhabdomyosarcoma, and small cell carcinoma. Intraspinal PNETs are rare neoplasms that are usually metastatic in origin. We describe the eighth reported primary PNET of the cauda equina that developed in a 52-year-old man with no significant medical history. The tumor was characterized by Homer-Wright rosettes and immunoreactivity for CD99, glial fibrillary acidic protein, neuron-specific enolase S100, and synaptophysin. The anatomic location of primary intrathecal PNETs is important as those arising in the spinal cord develop in the central nervous system, whereas those arising in the cauda equina develop in the peripheral nervous system. The histogenesis of intrathecal PNETs may be multifactorial.  相似文献   
59.
60.
A 13 year old girl was referred with congenital microcephaly, developmental delay, a prominent nose, highly arched palate, and an apparently low set left ear. She was found to have a pericentric inversion of one chromosome 7 and a ring chromosome 8, 46,XX,inv(7) (pter----p22::q11.23----p22::q11.23----qter), r(8) (p23q24.3). The concurrence of these two abnormalities is a rare event and has not been reported previously.  相似文献   
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