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1.
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
2.
Subacute sclerosing panencephalitis (SSPE) is a rare, slowly progressing but invariably fatal disease that is related to a prior measles virus infection and most commonly affects paediatric patients. Magnetic resonance (MR) imaging is the modality of choice for determining such changes in white matter. SSPE typically demonstrates bilateral but asymmetric periventricular and subcortical white matter involvement. We herein report a rare case of unilateral white matter involvement in a 13-year-old boy with SSPE that closely simulated Rasmussen’s encephalitis. To the best of our knowledge, this is the first report of an atypical presentation on MR imaging in which SSPE was a rare cause of unilateral brain parenchymal involvement in a patient with intractable seizures.  相似文献   
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4.
Primary amyloidosis of larynx is an uncommon phenomenon, the precise etiopathogenesis of which is not yet clear. It can present with slowly increasing hoarseness or difficulty in breathing. It presents more commonly as infiltrative lesion, exophytic presentation is a rare occurrence.  相似文献   
5.
Summary.  Antiangiogenesis agents are now being used in clinical trials to reduce the risk of recurrence of cancer. Several of these agents, however, are associated with thrombosis, especially when used in combination with chemotherapy. Antiangiogenesis and thrombosis are both endothelial-related activities, and we therefore evaluated one presumed antiangiogenesis agent (thalidomide) on intact cultured endothelial cells, and on cultured endothelial cells injured by preincubation with doxorubicin. We evaluated cell viability, caspase-3 activation, morphology of cells using light microscopy, and protease activated receptor-1 (PAR-l) expression. In our experiments, doxorubicin induced a dose- and incubation time-dependent and caspase-3-mediated apoptosis of endothelial cells. Thalidomide alone caused no changes in intact endothelial cells in terms of morphology, cell viability or activation of caspase-3. In contrast, when thalidomide was added to doxorubicin-injured endothelial cells, there was protection from cell death, increase in viability of endothelial cells, induction of differentiation and formation of neotubules. Doxorubicin reduced the expression of thrombin receptor, PAR-1, as evaluated by immunostaining and flow cytometry. Thalidomide did not alter PAR-1 expression in untreated cells but restored its expression reduced by doxorubicin. These findings suggest that thalidomide may be procoagulant, not by enhancing doxorubicin-mediated endothelial cell injury, but by altering the expression of PAR-1 on injured endothelium and resulting in endothelial dysfunction, which may explain hypercoagulability in patients treated with chemotherapy followed by thalidomide.  相似文献   
6.
A 55 years male presented with hoarsness of voice (4 months), cough (1 month), difficulty in breathing (15 days). Patient underwent an emergency tracneostomy and further workup proved it to be a case of verrucous carcinoma of larynx. Patient was treated surgically with satisfactory result.  相似文献   
7.
Primary malignant melanoma of cervix is a rare entity. A case of primary malignant melanoma of cervix presented with vaginal discharge and black colored growth over cervix. Histology showed malignant pleomorphic cells with melanin pigment in the cytoplasm.  相似文献   
8.
The strain diversity in Plasmodium falciparum has been studied with respect to gamete surface antigens which are the targets of transmission-blocking antibodies. Of 12 isolates tested, 11 were positive by immunofluorescence with the three monoclonal antibodies studied. The exception was a Liberian isolate, two clones of which were found to react with only one of the three monoclonal antibodies. Antibodies IIC5-B10 and IA3-B8, which previously have been shown to act synergistically to block infectivity of 7G8, a Brazilian clone of P. falciparum, acted in an exactly similar way with another Brazilian isolate, It.D12, and an isolate from Thailand. In the presence of complement either IA3-B8 or a third antibody, IID2-A10, strongly suppressed infectivity of It.D12 as well as 7G8, but neither isolate was strongly suppressed by IIC5-B10. IA3-B8 and IID2-A10 did not react by immunofluorescence or immunoprecipitation with gametes of L.E5; IIC5-B10 reacted positively with L.E5 gametes in these tests. In the absence of complement, the combination of IA3-B8 and IIC5-B10 did not suppress infectivity of L.E5 to mosquitoes. In contrast to its effect on gametocytes of other isolates, IIC5-B10 in the presence of complement strongly suppressed infectivity of L.E5 to mosquitoes. These results imply that IA3-B8 and IIC5-B10 react with two structurally distinct epitopes on the surface of gametes of P. falciparum and that the properties of both epitopes on gametes of L.E5 differ from those on gametes of the other isolates tested.  相似文献   
9.
The molecular mechanism(s) involved in mediating Ca2+ entry into rat parotid acinar and other non-excitable cells is not known. In this study we have examined the kinetics of Ca2+ entry in fura-2-loaded parotid acinar cells, which were treated with thapsigargin to deplete internal Ca2+ pools (Ca2+-pool-depleted cells). The rate of Ca2+ entry was determined by measuring the initial increase in free cytosolic [Ca2+] ([Ca2+]i) in Ca2+-pool-depleted, and control (untreated), cells upon addition of various [Ca2+] to the medium. In untreated cells, a low-affinity component was detected with K Ca = 3.4 ± 0.7 mM (where K Ca denotes affinity for Ca2+) and V max = 9.8 ± 0.4 nM [Ca2+]i /s. In thapsigargin-treated cells, two Ca2+ influx components were detected with K Ca values of 152 ±  79 μM (V max = 5.1 ± 1.9 nM [Ca2+]i/s) and 2.4 ±  0.9 mM (V max = 37.6 ± 13.6 nM [Ca2+]i/s), respectively. We have also examined the effect of Ca2+ and depolarization on these two putative Ca2+ influx components. When cells were treated with thapsigargin in a Ca2+-free medium, Ca2+ influx was higher than into cells treated in a Ca2+-containing medium and, while there was a 46% increase in the V max of the low-affinity component (no change in K Ca), the high-affinity component was not clearly detected. In depolarized Ca2+-pool-depleted cells (with 50 mM KCl in the medium) the high-affinity component was considerably decreased while there was an apparent increase in the K Ca of the low-affinity component, without any change in the V max. These results demonstrate that Ca2+ influx into parotid acinar cells (1) is increased (four- to five-fold) upon internal Ca2+ pool depletion, and (2) is mediated via at least two components, with low and high affinities for Ca2+. Received: 30 October 1995/Received after revisionand accepted: 13 December 1995  相似文献   
10.
Water-clear cell hyperplasia is a rare but well-documented cause of primary hyperparathyroidism. Parathyroid adenomas of water-clear cell type are exceptionally rare, and only five case reports are available at present in the medical literature. We report an additional case of water-clear cell adenoma of the parathyroid gland, and the differential diagnoses are discussed.  相似文献   
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