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1.
2.
We report an unusual case of primary cutaneous embryonal rhabdomyosarcoma presenting as a solitary skin lesion on the anterior chest of a 20-month-old child. The tumor was characterized by small, round to oval, poorly differentiated cells. Immunohistochemically, the tumor was negative for NSE, S-100 protein, LCA, and keratin but positive for muscle-specific actin, myoglobin, desmin, and vimentin, thus indicating the presence of myogenous differentiation. Ultrastructural analysis demonstrated thick and thin filaments. Special studies showed no evidence of a primary rhabdomyosarcoma in the patient at a more typical location, nor was there any evidence of metastases. 相似文献
3.
Total anorectal reconstruction with a double dynamic graciloplasty after abdominoperineal reconstruction for low rectal cancer 总被引:7,自引:3,他引:4
Bastiaan P. Geerdes M.D. Frans A. N. Zoetmulder M.D. Ph.D Erik Heineman M.D. Ph.D. Egbert J. Vos M.Sc. Mart -Jan Rongen M.D. Cor G. M. I. Baeten M.D. Ph.D. 《Diseases of the colon and rectum》1997,40(6):698-705
PURPOSE: Total anorectal reconstruction with a double dynamic graciloplasty was performed after abdominoperineal reconstruction
(APR) for low rectal cancer. In four patients an additional pouch was constructed to improve neorectal motility and capacity.
The aim of this study was to evaluate the results in the first 20 patients and to report on the preliminary results of patients
with an additional pouch. METHODS: Twenty patients with a mean age of 52 (range, 25–71) years and a rectal tumor at a mean
of 3 (range, 0–5) cm from the anal verge were treated. In 14 patients the Miles resection, colon pull-through, and construction
of a neosphincter were performed in one session. Six patients had the double graciloplasty at an average of 4.1 (range, 1.1–8.8)
years after APR. In four patients a pouch was constructed with an isolated segment of distal ileum. RESULTS: After a mean
follow-up of 24 (range, 1–60) months after APR, none of the patients developed local recurrence, whereas four patients developed
distant metastasis. Fifteen of 20 patients were available for evaluation, and 5 patients were still in training. Of these
15 patients, 8 patients were continent (53 percent), 2 patients were incontinent, and in 5 patients the perineal stoma was
converted to an abdominal stoma. Failures were attributable to necrosis of the colon stump (n=2) and incontinence (n=3). At
26 weeks mean resting pressure was 44 (standard deviation (SD), 28) mmHg, and mean pressure during stimulation was 90 (SD,
46) mmHg at a mean of 35 (SD, 1.2) volts at 52 weeks. Mean defecation frequency was three times per day (range, 1–5). Of the
eight patients who were continent, six used daily enemas. Mean time to postpone defecation was 11 (range, 0–30) minutes. CONCLUSION:
In experienced hands, the double dynamic graciloplasty is an oncologically safe procedure that can have an acceptable functional
outcome in a well-selected group of patients. However, to improve the outcome, further modifications will be necessary. So
far, the addition of a pouch has not resulted in improved outcome.
Supported by the Profileringsfonds of the Maastricht University Hospital, The Netherlands, and by the Stichting Fondsenwervingsactie
Volksgezondheid, Amsterdam, The Netherlands.
Read in part at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1995. 相似文献
4.
Five patients with orbital pseudotumor refractive to initial therapy are discussed. Three had a destructive granulomatous process associated with a sclerosing component. Two exhibited a predominantly lymphocytic infiltration. Chemotherapy with Prednisone (100 mg/day) and either Cytoxan (100 mg/day) or Chlorambucil (10 mg/day) in 5-day pulses is described. All patients responded clinically to this treatment without unfavorable side effects. 相似文献
5.
R A Blouin B A Hamelin D A Smith T S Foster W J John H A Welker 《Antimicrobial agents and chemotherapy》1992,36(3):632-638
In this open-label study, the disposition of fleroxacin in liver disease in 12 healthy male volunteers, 6 male cirrhotics without ascites (group A), and 6 male cirrhotics with ascites (group B) was evaluated. Fleroxacin (400 mg) was administered orally and intravenously to each subject in a random crossover fashion. Fleroxacin was completely absorbed and achieved similar peak concentrations in plasma in all three study groups (P greater than 0.05). The volume of distribution exceeded 1 liter/kg in healthy controls and was not affected by liver impairment (P greater than 0.05). Only group B demonstrated differences in the pharmacokinetic parameters evaluated: the systemic and renal clearances of fleroxacin and the renal clearances and clearances of the two major metabolites of fleroxacin formed, N-demethyl fleroxacin and fleroxacin N-oxide, were significantly lower and the half-lives of the parent drug and its metabolites were significantly longer in group B than in healthy controls and group A (P less than 0.05). The elimination of the two metabolites appeared to be formation rate limited in all three study groups. It was concluded from this study that a 50% reduction in the fleroxacin maintenance dose in patients with liver disease appears justified only in patients with ascites. However, no change in the fleroxacin loading dose is needed in patients with compromised liver function. 相似文献
6.
David Quarcoo Tanja C Fischer Nora Peckenschneider David A Groneberg Pia Welker 《Journal of occupational medicine and toxicology (London, England)》2009,4(1):8
Background
Neurotrophin 3 (NT-3) is a member of the neurotrophin family, a group of related proteins that are known to regulate neuro-immune interactions in allergic diseases. Their cellular sources and role in the recruitment of mast cell precursors in atopic dermatitis have not been characterized in detail so far. 相似文献7.
In mammals, the indolealkylamine melatonin is synthesized mainly in the pineal gland and to a lesser degree in a number of extrapineal sites. To obtain more information on its distribution, melatonin was measured in the membranous cochlea of the guinea pig. Moreover, melatonin and other serotonin derivatives were determined in organ cultures after incubation with 14C-labelled serotonin. The results show that melatonin is detectable in the organ of Corti and the basilar membrane, and to a lesser degree also in the cochlear nerve and stria vascularis, including the spiral ligament. In vitro studies reveal the occurrence of a number of radiolabelled serotonin derivatives indicating that two of the melatonin-forming enzymes, serotonin N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) are present in membranous cochlea. It is concluded that melatonin is synthesized in the guinea pig cochlea. Its role as modulator of hair cell function is dissolved. 相似文献
8.
9.
Retroviral vectors derived from murine leukemia virus (MLV) have been pseudotyped with a variant of the envelope glycoprotein (Env) of nonpathogenic simian immunodeficiency virus from African green monkeys (SIVagm) to result in [MLV(SIVagm-wt)] vector particles. The variant env gene encodes a full-length surface envelope glycoprotein (SU) and a C-terminally truncated transmembrane protein (TM). To change the coreceptor usage of this vector from CCR5 to CXCR4, which is predominant on human CD4-positive lymphocytes, the putative V3-loop of SIVagm SU was replaced by that of the T cell tropic HIV-1 variant BH10. The resulting [MLV(SIVagm-X4)] vectors were shown to specifically transduce CD4/CXCR4-positive cell lines, demonstrating the equivalent function in cell entry and choice of coreceptor usage of the V3-loops of SIVagm and HIV-1. These modified vectors were able to transduce primary human lymphocytes and were resistant to neutralization by sera from HIV-1-infected individuals. The [MLV(SIVagm-X4)] pseudotype vector generated is thus a promising candidate vector, e.g., for in vivo gene therapy of HIV-1 infection. 相似文献
10.
Samei E Buhr E Granfors P Vandenbroucke D Wang X 《Physics in medicine and biology》2005,50(15):3613-3625
The modulation transfer function (MTF) is well established as a metric to characterize the resolution performance of a digital radiographic system. Implemented by various laboratories, the edge technique is currently the most widespread approach to measure the MTF. However, there can be differences in the results attributed to differences in the analysis technique employed. The objective of this study was to determine whether comparable results can be obtained from different algorithms processing identical images representative of those of current digital radiographic systems. Five laboratories participated in a round-robin evaluation of six different algorithms including one prescribed in the International Electrotechnical Commission (IEC) 62220-1 standard. The algorithms were applied to two synthetic and 12 real edge images from different digital radiographic systems including CR, and direct- and indirect-conversion detector systems. The results were analysed in terms of variability as well as accuracy of the resulting presampled MTFs. The results indicated that differences between the individual MTFs and the mean MTF were largely below 0.02. In the case of the two simulated edge images, all algorithms yielded similar results within 0.01 of the expected true MTF. The findings indicated that all algorithms tested in this round-robin evaluation, including the IEC-prescribed algorithm, were suitable for accurate MTF determination from edge images, provided the images are not excessively noisy. The agreement of the MTF results was judged sufficient for the measurement of the MTF necessary for the determination of the DQE. 相似文献