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排序方式: 共有963条查询结果,搜索用时 15 毫秒
1.
Paul Devakar Yesudian MD Srivilliputtur G.S. Krishnan MBBS Muriugaiya Jayaraman MD Vanakampadi R. Janaki MD Patrick Yesudian FRCP 《International journal of dermatology》1997,36(3):194-196
Background Pemphigus is a group of vesiculobullous disorders in which the blisters usually heal with hyper- or hypopigmentation. The appearance of acanthomata at sites of previous blisters has been noted in some cases. Methods All cases of pemphigus admitted to the Madras Medical College hospitals during a 2-year period from March 1993 to March 1995 were taken into the study and screened for the presence of acanthomata. Results Fifty-two cases of pemphigus were identified, 47 of pemphigus vulgaris and five of pemphigus foliaceus; and of these 13 developed acanthomata when the blisters healed. Ten of these cases were of pemphigus vulgaris and three were of pemphigus foliaceus; biopsy of these lesions showed hyperkeratosis, acanthosis, papillomatosis, and intraepidermal clefting. Immunofluorescence carried out in two of these acanthomata also showed intercellular fluorescence. Conclusions The occurrence of acanthomata in healed lesions of pemphigus is not uncommon; because histopathologic and immunofluorescence evidence of disease activity is present, cases of this sort require careful follow-up. 相似文献
2.
J. L. Hedrick K. Carter M. Sanchez R. Di Pietro S. Swanson S. Jayaraman J. G. McGrath 《Macromolecular chemistry and physics.》1997,198(2):549-559
A new route for the synthesis of high glass transition temperature, thermally stable polymer foams has been developed, using compositionally asymmetric microphase-separated block copolymers where the minor component (poly(propylene oxide)) is thermally labile and the major component (polyimide) is thermally stable. The minor component decomposes to low molecular weight species upon heating, and the decomposition products diffuse out of the film, leaving behind pores embedded in a matrix of the thermally stable component. In this study, the polyimide block was crosslinked with ethynyl functionalities to obtain a stable porous structure. The decomposition of the propylene oxide in the block copolymer was studied by thermogravimetric, dynamic mechanical and thermomechanical analyses. Mild conditions were required to avoid rapid depolymerization of the propylene oxide and plasticization of the polyimide matrix. The foams showed pore sizes with diameters up to a micrometer in size as well as the expected reduction in the mass density. 相似文献
3.
Inhibition of interleukin-2 production by adherent cell factors from lepromatous leprosy patients. 总被引:1,自引:2,他引:1 下载免费PDF全文
I Nath J Jayaraman M Sathish L K Bhutani A K Sharma 《Clinical and experimental immunology》1984,58(3):531-538
Twenty-four hour supernatants (MoF) were obtained from monocyte rich 2 h adherent cells of 19 leprosy patients and four healthy contacts. MoF from borderline and lepromatous patients produced 52-61% inhibition of human interleukin-2 (IL-2) production by a PHA conditioned T cell line (Jurkat). Non-adherent cell supernatants and MoF from tuberculoid and healthy individuals had little effect on IL-2 production. The suppression effected by MoF was in the first 12 h of initiation of PHA stimulated Jurkat cell cultures. Suppressive MoF did not interfere with (1) IL-2 release, (2) IL-2 utilization by Con A-induced T cell blasts or (3) constitutive proliferation of Jurkat cells. Such MoF were released spontaneously from adherent cells of bacilliferous leprosy patients but required in vitro antigen triggering in long term treated lepromatous patients. It is possible that the unresponsiveness associated with lepromatous leprosy is related to the inhibition of IL-2 production by suppressive factors, thereby, preventing the further expansion of antigen reactive T cells. 相似文献
4.
Cbl-b differentially regulates activation-induced apoptosis in T helper 1 and T helper 2 cells 总被引:2,自引:0,他引:2
We previously reported that ligation of CD3 induces antiapoptotic signals in T helper 2 (Th2) cells, and in contrast causes Th1 cells to undergo apoptosis. Here we show that Cbl-b is accountable for the unequal response, revealing a previously unknown cell-specific regulatory function for the molecule. Absence of Cbl-b resulted in resistance to activation-induced apoptosis in murine Th1 cells following CD3 ligation, akin to what is observed in Th2 cells containing Cbl-b. Concurrent with the apoptosis profile, CD3 ligation in the absence of Cbl-b induced raft mobilization and cytoskeletal rearrangement in Th1 cells. Despite their ability to signal from CD3, Th2 cells did not aggregate their rafts, providing an explanation for cell-specific activity of Cbl-b. 相似文献
5.
Harish K Sharmila SP Revadi PS Prabha CV Padmini J Muley PR 《Indian journal of pathology & microbiology》2005,48(3):377-378
Lipoma primary to uterus is a rare entity among uterine fatty tumors. These create preoperative diagnostic confusion and their histogenesis is still unclear. Only a few cases of pure lipoma of uterus have been reported in the last few decades. A case of isolated pure lipoma primary to uterus diagnosed postoperatively by pathological examination is presented. 相似文献
6.
The delayed-type hypersensitivity (DTH) reaction to the phenyltrimethylamino (TMA) hapten in mice has been investigated. TMA-derivatized syngeneic spleen cells (TMA-SC) administered s.c. in several strains of mice consistently evoked DTH reactivity, as measured by footpad swelling after challenge with the diazonium salt of TMA. DTH could be induced by low levels of anti-idiotypic antisera (anti-Id) in lieu of antigen. The DTH reaction induced by either mode was hapten-specific, could be transferred into naive recipients by viable lymph node cells but not with serum from immune mice and was not influenced by cyclophoshamide pretreatment. Unlike TMA-SC which induced DTH in all of the strains of the mice tested, anti-Id induced DTH only in strains of the Igh-1e allotype. Positive DTH reactions were induced by anti-Id in the C57.Ige strain (H-2b, Igh-1e) but not in its allotype-congenic partner C57BL/6J (H-2b, Igh-1b). Interestingly this reaction could be suppressed if relatively high amounts of anti-Id were inoculated i.v. just prior to antigen challenge. In addition, the administration of anti-Id 1 h prior to antigen challenge in TMA-SC-sensitized mice significantly blocked the DTH reaction only in the Igh-1e strains. These results demonstrate that the induction and abrogation of TMA-specific DTH by anti-Id is linked to the IgCh locus. 相似文献
7.
8.
Cholecystokinin and neurotensin mRNAs are differentially expressed in subnuclei of the ventral tegmental area 总被引:1,自引:0,他引:1
Immunohistochemical studies of ventral tegmental area (VTA) neurons indicate that individual cells can contain dopamine as well as the neuropeptide neurotransmitters cholecystokinin (CCK) and neurotensin (NT). We have defined the distribution of the cells expressing the mRNAs encoding these two dopamine cotransmitter peptides in each of the subnuclei of the ventral tegmental area, and quantitated the extent of expression of each gene by using in situ hybridization methods. These studies reveal significant differences in the patterns of expression of each of these two genes within various subdivisions of the VTA. The rostral linear nucleus contained numerous CCK positive cells, some of which appeared to express preproCCK-mRNA at a very high level, but this nucleus contained relatively few NT-expressing cells. The parabrachialis pigmentosus contained numerous NT and CCK positive cells. The paranigralis and interfascicularis nuclei displayed positive CCK cells but with expression at only modest levels. NT cells were very few in these nuclei. The caudal linear nuclei contained the highest number of NT-expressing neurons and these cells expressed very high levels of NT mRNA. The selective distribution of these peptide genes within the VTA subnuclei may have specific consequences. Studies of the connectivity of neurons in the VTA show that the different subnuclei of this region project to several functionally and architectonically different regions of the cerebral cortex and subcortically to nuclei related to the limbic system. Results from our study show very prominent expression of CCK mRNAs in those subnuclei that project heavily to the prefrontal, other cortical areas, and the amygdaloid complex. The NT gene is expressed prominently in those subnuclei of VTA that project heavily to the entorhinal cortex and amygdaloid complex. These results provide support for a differential role for the NT-expressing neurons than that of CCK-expressing neurons of VTA in "reward" mechanisms and in drug-seeking and motivational behavior. These observations could be applied to create working hypotheses and experimental paradigms to test the differential functional activity of the subdivisions of VTA and their potential roles in the pathogenesis and treatment of drug-seeking behavior and other neuropsychiatric disorders. 相似文献
9.
10.
Bowers KW Edmonds JL Girod DA Jayaraman G Chua CP Toby EB 《The Journal of bone and joint surgery. American volume》2000,82(5):694-704
BACKGROUND: Osteocutaneous radial forearm free flaps have fallen from favor due to pathological fractures of the radius. The purposes of this study were to propose a means to decrease the rate of pathological fracture by prophylactic fixation of the donor-site defect and to evaluate this technique biomechanically. METHODS: Two groups of ten matched pairs of fresh-frozen cadaveric radii were harvested. In Group 1, an eight-centimeter length of radius comprising 50 percent of the cross-sectional area of the bone was removed to simulate an osteocutaneous radial forearm donor-site defect. This defect was created in one member of each pair, with the other bone in the pair left intact. In Group 2, both members of the ten matched pairs of radii had identical defects created as previously described. However, one radius in each pair had a twelve-hole, 3.5-millimeter dynamic compression plate placed across the segmental defect. In each group, five matched pairs were tested to failure in torsion and five matched pairs were tested to failure in four-point bending. RESULTS: In Group 1, the intact radius was a mean of 5.7 times stronger in torsion and 4.2 times stronger in four-point bending than the radius with the segmental resection. In Group 2, the radius that was ostectomized and fixed with a plate was a mean of 4.0 times stronger in torsion and 2.7 times stronger in four-point bending than the ostectomized radius. CONCLUSIONS: Removal of an eight-centimeter segment from the radius dramatically decreased both torsion and bending strength. Application of a plate over the defect in the radius significantly restored the strength of the radius (p = 0.01). 相似文献