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排序方式: 共有247条查询结果,搜索用时 15 毫秒
31.
32.
Samaiya A Deo SS Thulkar S Hazarika S Kumar S Parida DK Shukla NK 《World journal of surgical oncology》2005,3(1):3-7
BACKGROUND: Malignant small bowel tumors are very rare and leiomyosarcoma accounts for less than 15% of the cases. Management of these tumors is challenging in view of nonspecific symptoms, unusual presentation and high incidence of metastasis. In this case report, an unusual presentation of jejunal sarcoma and management of liver metastasis with radiofrequency ablation (RFA) is discussed. CASE PRESENTATION: A 45-year-old male presented with anemia and features of small bowel obstruction. Operative findings revealed a mass lesion in jejunum with intussusception of proximal loop. Resection of bowel mass was performed. Histopathological findings were suggestive of leiomyosarcoma. After 3-years of follow-up, the patient developed recurrence in infracolic omentum and a liver metastasis. The omental mass was resected and liver lesion was managed with radiofrequency ablation. CONCLUSION: Jejunal leiomyosarcoma is a rare variety of malignant small bowel tumor and a clinical presentation with intussusception is unusual. We suggest that an aggressive management approach using a combination of surgery and a newer technique like RFA can be attempted in patients with limited metastatic spread to liver to prolong the long-term survival in a subset of patients. 相似文献
33.
BACKGROUND: Preoperative lymphoscintigraphy is one of the three methods of evaluating sentinel nodes in patients with breast cancer; however, it has been reported to have a high false negative rate. CASE PRESENTATIONS: We report here two cases where the preoperative lymphoscintigraphy was found to be fallacious. A 44-year-old female with T2N0 breast cancer underwent preoperative lymphoscintigraphy with Tc99 sulfur colloid which failed to show any uptake in axilla or internal mammary chain. Intraoperative scintigraphy with blue dye and hand held gamma probe identified sentinel lymph node in axilla. Another patient with T2N0 lesion underwent preoperative lymphoscintigraphy which showed a sentinel lymph node in axilla and another in supraclevicular fossa. Intraoperative scintigraphy failed to show supraclevicular node however axillary node was correctly identified. CONCLUSION: These two cases further strengthen the need to carry out triple test in identification of sentinel lymph node in patients with breast cancer. It also demonstrates the fallacies of preoperative lymphoscintigraphy. 相似文献
34.
35.
Elizabeth E. Romero Leonardo J. Velazquez-Estades Rajat Deo Brian Schapiro David A. Roth 《Experimental cell research》1998,243(2):334
Vitamin K-dependent carboxylase catalyzes the posttranslational modification of glutamate to γ-carboxyglutamate (Gla) in its substrates, the vitamin K-dependent proteins (VKDPs). This modification is required for the activities of the VKDPs. Recent evidence demonstrates previously unrecognized roles for VKDPs as signaling molecules important in the regulation of cell growth, adhesion, and apoptosis, suggesting developmental functions for VKDPs and hence the carboxylase. The tissue distribution and functions of carboxylase in development are unknown. In this study, we isolated and characterized the full-length cDNA encoding the rat carboxylase and analyzed, at the cellular level, the expression of this gene in rat embryos byin situhybridization. We demonstrate that the expression of this gene is highly regulated in a developmental and tissue-specific manner. Hepatocytes, the major site of synthesis of VKDPs of blood coagulation, express carboxylase mRNA late in gestation, in contrast to the central nervous system, mesenchymal, and skeletal tissues which express carboxylase mRNA early during rat embryogenesis. The tissue-specific temporal expression of the carboxylase gene during embryogenesis indicates that vitamin K-dependent carboxylation and the formation of Gla is developmentally regulated. These studies suggest that vitamin K-dependent carboxylation is an important modulator of embryonic VKDP function. 相似文献
36.
Abhay R. Redkar Shilpa Kadam Madhav G. Deo Rita Mulherkar 《Journal of biosciences》1997,22(5):529-536
Enhancing factor (EF), a mouse phospholipase A2 (PLA2), has been purified from the small intestines, based on its ability to increase the binding of epidermal growth factor in
a radioreceptor assay. EF/PLA2 was found to be localized predominantly in the Paneth cells in the small intestines. Whether mouse intestinal EF/PLA2 is identical/similar to mouse secretory PLA2 was to be determined. Phospholipases are known to play a crucial role in the process of inflammation. This paper reports
the presence of trace amounts of EF/PLA2 in the peritoneal exudate cells. Western blot analysis of the acid extracts showed the presence of a 14 kDa immunologically
cross-reactive protein. RT-PCR analysis using EF specific primers amplified a ∼700 bp product which was further confirmed
to be EF-specific by nested PCR analysis and sequencing. Presence of EF in the peritoneal exudate cells could be a unique
mode of transport of growth factor modulator to the site of injury to aid in regeneration/cell proliferation of damaged tissue. 相似文献
37.
Singh Tryambak Deo Mizuno Kiyonobu Kohno Tomoko Nakamura Shun 《Neurochemical research》1997,22(7):791-797
Development of the central somatosensory system is profoundly modulated by the sensory periphery. Cauterization of facial whiskers alters the segregation pattern of barrels in rodents only during a few days just after birth (critical period). Although a molecular basis of the segregation of barrel neurons and the critical period for the anatomical plasticity observed in layer IV barrel neuron is not clear yet, the accumulating evidence suggests that neurotrophins modulate synaptic connections including central nervous system. In this study, we showed by in situ hybridization that mouse barrel side neurons express brain-derived neurotrophic factor (BDNF) mRNA and both catalytic and non-catalytic forms of trkB mRNA. Cautery of row C vibrissae on the right side of the face within 24 h after birth (post natal day 0, PND0) reduced the expression of BDNF and trkB mRNA from the division region between the contralateral row C barrels at PND7. The vibrissae in row A, C, and E were cauterized at PND0 followed by quantitative RT-PCR for BDNF and trkB mRNA with total RNA isolated from the barrel region at PND7. The result showed that BDNF, but not trkB, mRNA was increased several-fold in the contralateral barrel region. These data suggest that the expression of BDNF mRNA is differentially regulated between injured barrels and actively innervated barrels. The differential expression of the mRNA encoding neurotrophins and their receptors may be important in regulating the injury-dependent re-segregation of barrels. 相似文献
38.
Dipicolinic acid synthesis inPenicillium citreoviride strain 3114 was inhibited by Ca2+ ions, but not by Ba2+, Cu2+or Fe2+. Among the metals tested, only Zn2+ inhibited the synthesis of dipicolinic acid and promoted sporulation. None of these metals reversed the inhibition by Ca2+ or Zn2+. A mutant 27133-dpa-ca selected for resistance to feedback inhibition by dipicolinic acid: Ca2+ complex showed cross-resistance to inhibition by dipicolinic acid: Zn2+. Both 3114 and271 33-dpa-ca excreted a number of aliphatic and amino acids during secondary metabolism of dipicolinic acid. In the presence of 1000 ppm
of Ca2+, accumulation of citric acid and α-aminoadipic acid was completely inhibited under conditions of inhibition of dipicolinic
acid in parent strain 3114 but not in the mutant. Citric acid with or without Ca2+ did not inhibit thede novo synthesis of dipicolinic acid in the strain 3114. In fact, citric acid in the presence of Ca2+ improved significantly rate of dipicolinic acid synthesis. Apart from resistance to feed back inhibition by dipicolinic acid:
Ca2+ complex, mutant differed from the parent in three other aspectsviz. (i) dipicolinic acid synthesis was not subject to catabolite repression by glucose, (ii) sporulation as well as dipicolinic
acid synthesis was dependent on the presence of Ca2+ ions in the medium and (iii) Mg2+ requirement for the mutant increased three fold. Higher requirement of the Mg2+ could be partially relieved by Ca2+ during secondary metabolism. The results support the inference thatde novo synthesis of dipicolinic acid is regulated through feedback inhibition by dipicolinic acid: Ca2+complex. 相似文献
39.
Single batrachotoxin-activated sodium channels from rat brain were modified by trimethyloxonium (TMO) after incorporation in planar lipid bilayers. TMO modification eliminated saxitoxin (STX) sensitivity, reduced the single channel conductance by 37%, and reduced calcium block of inward sodium currents. These effects always occurred concomitantly, in an all-or-none fashion. Calcium and STX protected sodium channels from TMO modification with potencies similar to their affinities for block. Calcium inhibited STX binding to rat brain membrane vesicles and relieved toxin block of channels in bilayers, apparently by competing with STX for the toxin binding site. These results suggest that toxins, permeant cations, and blocking cations can interact with a common site on the sodium channel near the extracellular surface. It is likely that permeant cations transiently bind to this superficial site, as the first of several steps in passing inward through the channel. 相似文献
40.
Clostridium pasteurianum total cellular saturated fatty acids increased through its growth cycle from 81% to 91% but varied significantly in the composition
under nitrogen- and non-nitrogen-fixing conditions. During ammonia-assimilating growth, palmitic acid decreased from 67.7%
to 43.5% by late log while marked increases in shorter chain saturated fatty acids (C15:0 and below) and a long chain saturated C22:0 occured. In contrast, under N2-fixing growth conditions, palmitic acid increased from 45.5% to 84.3% by late log, representing nearly the total amound of
saturated fatty acids found inC. pasteurianum. The total cellular lipid concentration decreased as the culture aged. irrespective of the nitrogen sources; however, the
phospholipid concentration increased significantly during N2-fixing growth as compared with a 50% decrease during ammonia-assimilating conditions. The implication of these differences
and possible role of palmitic acid and phospholipids inC. pasteurianum nitrogen fixation process are discussed. 相似文献