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61.
There is agreement on the clinical diagnostic criteria for acute inflammatory demyelinating polyneuropathy (AIDP/GBS) however, there is lack of consensus for detection of demyelination. In order to critically evaluate the prevailing criteria, sixty-six patients who fulfilled NINCDS criteria and had typical features of GBS were studied for electrophysiological abnormalities of peripheral nerves by using standard methods (median, common peroneal, sural and ulnar) between 1 to 12 weeks after the onset of symptoms. The commonest abnormality on motor nerve conduction study was prolonged distal latency (75%-83%) followed by reduction in CMAP amplitude (63%-82%), decreased velocity (48%-62%), conduction block (17%-39%) and f-wave abnormalities (37.8%-59%). Sensory conduction abnormalities were detected in over 20% of median, 25% of ulnar and 33% of sural nerves. All the patients had abnormality of at least two motor conduction parameters in one nerve when values beyond 2 SD of the mean were considered abnormal and over 70% of patients had three abnormalities in two nerves or two abnormalities in three nerves. Comparison with the prevailing criteria for demyelination revealed that the number of patients fulfilling them varied widely: Albers et al. (1985): 74.2%, Albers et al. (1989): 40.9% and Cornblath: 30.3%. We believe that the current criteria for detection of demyelination in acute neuropathy are too strict, underestimate the underlying pathology in GBS and need reassessment.  相似文献   
62.
We report a case of Wernicke encephalopathy in which the only sign of acute disease was enhancement of the mamillary bodies. This case demonstrates the utility of gadolinium enhancement at MR imaging as a means of diagnosing or confirming the syndrome of Wernicke encephalopathy even in the absence of atrophy or T2 abnormalities within the diencephalon and mesencephalon.  相似文献   
63.
The number involved in and the rate of migration of donor leucocytes into the following recipient organs (spleen, thymus, bone marrow, lung and mesenteric lymph nodes) were measured in two rat models of orthotopic liver transplantation (OLT) using donor-specific MHC class I antibodies. The first OLT model is one that does not require immunosuppression in order to achieve tolerance and involved the transplantation of DA (MHC haplotype, RT1a) livers into PVG (RT1c) recipients. The second model was one that required a 7-day (10 mg/kg) treatment with cyclosporin A (CsA) to achieve tolerance and used DA donors into Lewis (RT1(1)) recipients. Recipient organs were biopsied on days 3, 20 and 87 following OLT and donor leucocyte migration was quantified by immunohistochemistry and computer densitometry of immunoblots of detergent-solublized tissues in order to resolve both membrane-bound and soluble donor MHC class I antigen. In a separate experiment, spleen biopsies were taken following OLT on days 3 and 15 from the naturally tolerizing OLT model (DA into PVG), treated with and without CsA for 7 days and compared with the (DA into Lewis) model. The initial rate of leucocyte migration between days 3 and 21 following OLT was found to be the most rapid into the spleen, followed by the bone marrow and mesenteric lymph nodes in the naturally tolerant (DA into PVG) model when compared with the (DA into Lewis) model. The number of donor leucocytes in the spleen and mesenteric lymph nodes in both models was, however, approximately the same by 87 days. No real difference in the rate of leucocyte migration was seen in the thymus or the lung for both transplant models over the time course assayed. CsA was found to lower the rate of donor leucocyte migration only over the period it was administered. The rate of donor leucocyte migration into the spleen was still much lower 15 days after OLT in the (DA into Lewis) model compared with the (DA into PVG) model treated with and without CsA. Thus the differences in the rate of donor leucocyte migration into the spleen, bone marrow and mesenteric lymph nodes immediately following OLT may offer an explanation as to why the (DA into PVG) combination is able to accept a transplanted liver without immunosuppressive therapy.  相似文献   
64.
We report a case of cervicofacial necrotizing fasciitis that developed after blepharoplasty, an occurrence that, to our knowledge, has not previously been reported in the medical literature. A patient who presented to our institution 3 days after undergoing blepharoplasty of the upper eyelid was diagnosed as having fulminant fasciitis involving extensive areas of the face, scalp, and neck. We review the case in detail and discuss clinical and radiological clues to diagnosis, surgical and medical management, wound care, and subsequent scar contracture. This case emphasizes the need for individualized, appropriate postoperative care and for an awareness of this rare, potentially fatal complication. Early recognition and aggressive treatment of cervicofacial fasciitis can arrest its rapid progression and prevent devastating sequelae.  相似文献   
65.
This study was designed to investigate the effect of retaining coronal tooth substance on the performance of post-retained core materials, and to compare the fracture resistance of the system with an intact tooth prepared to similar dimensions. Ten teeth restored with post-retained silver amalgam, and 10 teeth restored with silver-glass cermet, all with a retained single wall of coronal tooth substance, were compared with 10 unrestored teeth prepared to similar dimensions when subjected to a shearing load. The results showed no statistically significant difference between the unrestored teeth and those restored with a silver-glass cermet. Whilst the teeth restored with silver amalgam had a significantly higher fracture resistance (P > 0.01) there was greater tendency to root fracture.  相似文献   
66.
Filarial nematodes are a cause of chronic debilitating diseases in the tropics. A hallmark of filariasis is the marked down-regulation and polarization of host immune responses, yet molecular constituents of parasites causing this state have remained undefined. We describe a 17-kDa antigen (Av17) of the rodent filarial parasite Acanthocheilonema viteae, which shows amino acid homologies to cystatin C, a major cysteine protease inhibitor belonging to family 2 of the cystatin superfamily. Av17 is released by filariae in vitro. Exported molecules of A. viteae worms are shown to markedly suppress mitogen-induced T cell proliferation of mice and jirds. Av17 accounts for 45.5% of this suppressive activity in the murine system. Recombinant Av17 (rAv17), expressed in Escherichia coli, exhibits biological activity as a cysteine protease inhibitor and was used to examine the immunomodulatory effects, rAv17 induces down-regulation of murine T cell responses to mitogens, to T cell receptor cross-linking by anti-CD3 antibodies and to specific antigens, and at the same time up-regulation of interleukin-10. Hence, this filarial cystatin is a likely effector molecule of immunomodulation and a potential target for antifilarial intervention.  相似文献   
67.
Multiple trials using antiarrhythmic drugs, pharmacologic therapy, and implantable cardioverter defibrillators have been performed in an attempt to improve survival in patients: (1) postmyocardial infarction; (2) with congestive heart failure, with and without nonsustained ventricular tachycardia; and (3) with sustained ventricular tachycardia and those who have survived an out-of-hospital cardiac arrest. This article reviews some of the key findings and limitations of completed and ongoing trials. We also make recommendations for the current treatment of such patients based on the results of these trials.  相似文献   
68.
PURPOSE: To assess the efficacy and safety of percutaneous catheter drainage combined with alcohol sclerosis in the treatment of postoperative lymphoceles. PATIENTS AND METHODS: Thirteen patients with 14 postoperative symptomatic lymphoceles were treated. Drainage catheters were inserted under ultrasound (n = 13) or computed tomographic (n = 1) guidance. Lymphocele sclerosis was performed by instilling 10-100 mL of absolute alcohol into the lymphocele cavity and aspirating the alcohol after 30 minutes. Sclerosis sessions were carried out one to three times per day, usually three times per week. Catheter sinograms were obtained and prophylactic antibiotics administered. Imaging was repeated if symptoms or signs of recurrence developed. RESULTS: Successful drainage and sclerosis were achieved in all 13 patients. One patient with a recurrence was successfully treated with repeated drainage and alcohol ablation. No adverse effects of alcohol instillation were seen. The mean duration of catheterization was 36 days (range, 17-65 days; median, 30 days). CONCLUSION: Percutaneous drainage combined with alcohol ablation is a safe and effective treatment of postoperative lymphoceles.  相似文献   
69.
Endodontic treatment of maxillary and mandibular anteriors does not generally offer strenuous challenges to the skilled practitioner. Most cases are relatively straightforward and can be treated without complication. Anatomical and developmental variations do exist in these teeth, however, which can add an enormous degree of technical complexity, and even doom endodontic treatment to failure. The prudent clinician must be aware of these variations, modify treatment procedures accordingly, and inform the patient of these possible causes of treatment failure.  相似文献   
70.
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