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1.
Infantile Digital Fibroma Treated With Mohs Micrographic Surgery   总被引:2,自引:0,他引:2  
John G. Albertini  MD  Maj  USAF  MC  Michael Jude Welsch  MD  CPT  USA  MC  Leo A. Conger  MD  LTC  USA  MC  Lester F. Libow  MD  COL  USA  MC    Dirk M. Elston  MD  COL  USA  MC 《Dermatologic surgery》2002,28(10):959-961
BACKGROUND: Infantile digital fibroma (IDF) is a rare benign fibrous tumor of childhood that frequently recurs despite local excision. Conservative, nonsurgical management may result in regression and/or joint deformity. OBJECTIVE: To describe the histologic features of IDF and discuss a case excised using Mohs micrographic surgery (MMS). METHODS: Case report and review of the clinical, histologic, and ultrastructural features. RESULTS: Characteristic inclusion bodies of actin were identified with hematoxylin and eosin, Masson's trichrome, and rapid actin immunostain. The tumor was debulked and the majority was removed after one stage of MMS, except where the deep margin approached the joint space. The defect healed by secondary intention. At 2 years the patient had no recurrence or functional joint deformity. CONCLUSION: MMS is a surgical treatment option for IDF.  相似文献   
2.
Entry of opsonized pathogens into phagocytes may benefit or, paradoxically, harm the host. Opsonization may trigger antimicrobial mechanisms such as reactive oxygen or nitric oxide (NO) production but may also provide a safe haven for intracellular replication. Brucellae are natural intramacrophage pathogens of rodents, ruminants, dogs, marine mammals, and humans. We evaluated the role of opsonins in Brucella-macrophage interactions by challenging cultured murine peritoneal macrophages with Brucella melitensis 16M treated with complement- and/or antibody-rich serum. Mouse serum rich in antibody against Brucella lipopolysaccharide (LPS) (aLPS) and human complement-rich serum (HCS) each enhanced the macrophage uptake of brucellae. Combinations of suboptimal levels of aLPS (0. 01%) and HCS (2%) synergistically enhanced uptake. The intracellular fate of ingested bacteria was evaluated with an optimal concentration of gentamicin (2 microg/ml) to control extracellular growth but not kill intracellular bacteria. Bacteria opsonized with aLPS and/or HCS grew equally well inside macrophages in the absence of gamma interferon (IFN-gamma). Macrophage activation with IFN-gamma inhibited replication of both opsonized and nonopsonized brucellae but was less effective in inhibiting replication of nonopsonized bacteria. IFN-gamma treatment of macrophages with opsonized or nonopsonized bacteria enhanced NO production, which was blocked by N(G)-monomethyl L-arginine (MMLA), an NO synthesis inhibitor. MMLA also partially blocked IFN-gamma-mediated bacterial growth inhibition. These studies suggest that primary murine macrophages have limited ability to control infection with B. melitensis, even when activated by IFN-gamma in the presence of highly opsonic concentrations of antibody and complement. Additional cellular immune responses, e.g., those mediated by cytotoxic T cells, may play more important roles in the control of murine brucellosis.  相似文献   
3.
Alterations in tissue zinc levels have been documented in patients with gastrointestinal tract malignancies and more frequently, in those with colonic cancer. However, the precise role of tissue zinc in carcinogenesis is not well elucidated. This study, using a well-established colon cancer model in rats, was designed to investigate the relationship of tissue zinc to the carcinogenic process. The aim was to examine tissue zinc levels in the preneoplastic tissues and to study the changes that occur during transition of mucosa from normal to preneoplastic state. Six-week old rats were given a single dose subcutaneous injection of azoxymethane (AOM) (30mg/kg body weight) and sacrificed after 1, 2, 5, and 9 months of the treatment. Plasma zinc levels showed a significant decrease (p<0.05) at 9 months compared with controls. Tissue zinc levels showed a significant decrease in the large intestine at 1 and 2 months (p<0.05) and at 5 and 9 months (p<0.01), in the small intestine at 2, 5, and 9 months (p<0.05), and in the stomach at 5 and 9 months (p<0.05). The maximum percent decrease (45%) in tissue zinc was observed in the large intestine at 9 months. Tissue copper zinc super oxide dismutase (CuZnSOD) activity was assessed in the body of the stomach, small intestine, and large intestine and compared with the control group. There was a significant fall in CuZnSOD levels in the small intestine at 9 months (p<0.05) and in the large intestine at 5 and 9 months (p<0.01). Two of these six rats showed histological evidence of precancerous lesions in the mucosa of the colon. This study suggests that the decrease in plasma zinc, tissue zinc and activity of CuZnSOD is associated with development of preneoplastic lesions in the colonic mucosa.  相似文献   
4.
We describe non‐radiative energy‐transfer experiments to measure the rates of polymer interdiffusion in P(MMA‐co‐BA) latex films formed in the presence of poly(vinyl alcohol) (PVOH). PVOH had relatively little effect on the initial efficiency of energy transfer, even when the amount of PVOH was large enough to form the continuous phase. Since ΦET(0) is a measure of the interfacial area between D‐ and A‐labeled cells in the film, we conclude that under these circumstances the dispersed P(MMA‐co‐BA) copolymer is in the form of clusters with many contacts between particles containing D and A labels. These large amounts of PVOH also reduce the amount of polymer diffusion that takes place when the films are annealed. When smaller amounts of PVOH are present, the effects are measurable but much smaller. In the presence of 2 to 17 wt.‐% PVOH, the polymer diffusion rate is retarded. The magnitude of the effect increases with the amount of PVOH present, and the effect is larger at 45 °C than at 63 °C. We show that the PVOH has its largest influence at the very early stages of polymer diffusion.

Schematic representation of an energy transfer experiment, which monitors polymer interdiffusion in a latex film.  相似文献   

5.
Lipid peroxidation was assessed in the sera and various organs of rats experimentally infected with Trypanosoma brucei. Thirty-six adult albino rats divided into 2 groups of eighteen rats each were used in this study. In experiment one, a group of 18 rats were used and they were divided into three groups (A, B and C) of six rats each. Groups B and C rats were infected with 1.54 × 105 trypanosomes per rat intraperitoneally, whereas group A served as uninfected control. The rats were bled on day 0 and subsequently at 7-day intervals for packed cell volume (PCV), sera peroxidation index and parasitaemia. Also, temperature and weight were taken on day 0 and subsequently at 7-day intervals. In experiment 2, 18 rats were also used. Six rats each were sacrificed on days 0, 14 and 28-postinfection. Five rats each were sacrificed on day 14 and day 28 post-infection (PI) from group B, and their organs were promptly collected and washed with normal saline and used for organ malondialdehyde (MDA) concentration. The infection led to an increase in lipid peroxidation index (MDA concentration) of sera samples. The serum MDA concentration of the infected rat group was significantly (p < 0.01) higher than in the uninfected group on days 21 and 28 PI. The increase was however reversed by diminazene aceturate (Berenil; Hoechst, Ireland) treatment at the dosage of 7 mg/kg body weight administered on day 14 PI. The organ lipid peroxidation index also increased significantly (p < 0.05) in the eye, lung and spleen. However, there was no significant (p > 0.05) increase of lipid peroxidation index in the kidney, heart, liver, testes and brain. Also, the mean weekly MDA concentration increased as the disease progressed, the mean weekly temperature and parasitaemia also increased, but the reverse was the case with the mean weekly body weight and PCV which declined as the disease progressed. The findings are indication that oxidative stress plays an important role in the pathology of trypanosomosis.  相似文献   
6.
Eight subjects with acute functional psychoses receiving unmodified electroconvulsive therapy (ECT) at Ibadan were investigated for occult or subclinical internal tissue damage by serial measurements of eight acute phase reactants. Samples of venous blood were collected from each patient at pretreatment, two within treatment, and one at posttreatment. The acute phase proteins assayed were C-reactive protein (CRP), alpha-2-macroglobulin, ceruloplasmin, factor B, C-4 protein, C-3 protein, transferin, and alpha-1-antitrypsin. Except for CRP, the values of the proteins did not change during treatment. CRP values decreased posttreatment and were not detectable in the last sample in five subjects in whom values had been present pretreatment. Our data do not support fears of occult internal tissue damage during unmodified ECT. The consistent decrease in CRP levels posttreatment when patients no longer exhibited psychotic symptoms could not be explained by type of psychosis, intramuscular injections, or changes in drugs and diet; its significance is not known.  相似文献   
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Social Psychiatry and Psychiatric Epidemiology - With the introduction of the prolonged grief disorder (PGD) in the ICD-11 and most likely in the future DSM-5-TR, there is clinical need to examine...  相似文献   
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