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81.
Abstract

Sarcoidosis is a chronic, multisystem noncaseating granulomatous disease of unknown etiology. Sarcoidosis typically presents clinically in individuals between the ages of 20 and 40 years. Although sarcoidosis most commonly affects the respiratory system, nearly any organ system can be involved. Spinal cord involvement by sarcoidosis is a rare event, occurring in less than 1% of patients with systemic disease. The case presented is that of a 29-year-old black male with benign past medical history who presented with a 6-week history of progressive incomplete paraplegia arid bowel dysfunction. Magnetic resonance imaging revealed an intramedullary mass at the T-4-T-5 levels. The patient underwent thoracic laminectomy and debulking of the mass. The pathology was consistent with granulomatous disease. Postoperatively, the patient was placed on prednisone. He subsequently received comprehensive inpatient and outpatient rehabilitation and at present is bowel and bladder continent and ambulating at community levels with a rolling walker. The diagnosis of sarcoidosis; potential treatment options, including debulking and long-term steroid use; and prognosis will be discussed.  相似文献   
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The aim of this paper is to provide a systematic review of articles concerning primary osseointegrated dental implants in the head and neck oncology setting. We searched MEDLINE (1950 to March 2009) and Embase (1980 to March 2009) using the terms head and neck, oral, maxillofacial, craniofacial, jaws, mandible, maxilla, zygoma, dental implants, osseointegrated implants, implants, tumour, cancer, oncology, immediate, simultaneous, and primary. Two authors independently reviewed the abstracts, and all those written in the English language that referred to the placement of primary dental implants in patients with cancer of the head neck were included. Articles that referred to craniofacial or extraoral implants were excluded. Of 892 abstracts 83 were eligible for further consideration; the full articles were evaluated, and 41 that complied fully with the inclusion criteria are presented as a tabulated summary. There are three case reports, 13 reviews, and 25 clinical studies. Eight of the clinical studies refer solely to the insertion of dental implants at the time of primary oncological resection, and only two were of a prospective design. We have concisely summarised publications concerning primary dental implants, and our findings will help to inform head and neck cancer teams, particularly oncological surgeons, restorative dentists, and maxillofacial prosthodontists of the evidence base surrounding this approach to oral rehabilitation.  相似文献   
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Gold-195m, a radionuclide with a short half life (30.5 s) was used to quantify left to right intracardiac shunts. The results of this method were compared with those obtained with technetium-99m, a method that was validated against oximetry. In five patients the pulmonary to systemic flow ratio (greater than 3:1) obtained by both radionuclides indicated that the level of shunting was too high to be measured accurately. In one patient fragmentation of the bolus meant that no satisfactory gamma fit could be obtained. In the remaining 16 patients there was no significant difference between two successive 195mAu studies. The agreement between 99mTc results and 195mAu results was excellent. Oxygen administration, straight leg raising exercise, and the use of oblique projections did not affect the values of the pulmonary to systemic flow ratio. The technique of quantification of intracardiac shunts by 195mAu gives reproducible and accurate results and the low radiation dose means that it is suitable for use in children with suspected left to right shunts.  相似文献   
87.
Hepatopulmonary syndrome in candidates for liver transplantation   总被引:14,自引:0,他引:14  
BACKGROUND: Hepatopulmonary syndrome (HPS) has been defined as a clinical triad, including chronic liver disease, gas exchange defects (increased alveolar-arterial PO2 difference irrespective of the presence of arterial hypoxemia), and widespread intrapulmonary vascular dilatations. We determined the incidence and the clinical and pulmonary functional characteristics of HPS in candidates for orthotopic liver transplantation (OLT) and tested their predicted accuracy. METHODS: We studied 80 patients with cirrhosis prospectively, and carried out contrast-enhanced (CE) echocardiography and lung function tests, including ventilation-perfusion (V(A)/Q) distributions. RESULTS: Fourteen patients had HPS (incidence, 17.5%). Patients with HPS (49 +/- 12 (+/-SD) years) had more cutaneous spiders, finger clubbing and dyspnea (P < 0.05 each) and a lower diffusing capacity (DLCO, 56 +/- 18% predicted; P < 0.001) than non-HPS patients (n = 66). Mild to moderate V(A)/Q inequalities and increased intrapulmonary shunt were predominant in HPS patients, but oxygen diffusion impairment was observed in those with hypoxemia (n = 8) only. The DLCO showed a considerable area under the receiver operating characteristic curve (0.89). CONCLUSIONS: HPS in cirrhotic patient candidates for OLT shows a high incidence and these patients present with distinctive clinical and functional features compared with non-HPS individuals. The presence of a low DLCO may be of help for the diagnosis of HPS.  相似文献   
88.
Cardiac toxicity is a frequent manifestation in amitriptyline overdose and is felt to be due, in part, to sodium channel blockade by the drug. Another agent with sodium channel blocking properties, diphenylhydantoin, has been used clinically to reverse cardiac conduction abnormalities induced by amitriptyline. This reversal of toxicity is believed to occur secondary to competition for the sodium channel binding site. We evaluated individually and in combination the effects of amitriptyline (0.4 microM) and diphenylhydantoin (10-80 microM) on the sodium current in isolated rabbit atrial and ventricular myocytes at 17 degrees C. Using the whole-cell variant of the patch-clamp technique, we found that both amitriptyline and diphenylhydantoin reduced the sodium current in a use-dependent fashion. The time constant of recovery (tau r) from block by amitriptyline at -130 mV was very slow (13.6 +/- 3.2 seconds), whereas tau r during diphenylhydantoin exposure was fast (0.71 +/- 0.21 seconds, p less than 0.0001 compared with amitriptyline). During exposure of cells to a mixture of the two drugs, tau r was found to be 6.6 +/- 1.8 seconds, but no evidence of direct competition between amitriptyline and diphenylhydantoin was seen. Attempts to fit the recovery data of the mixture to two exponentials resulted in no significant improvement in the fit when compared with that using a single exponential. Use of the sodium channel blocking agent lidocaine (similar kinetics to diphenylhydantoin) in competition with amitriptyline resulted in findings consistent with direct competition of these two drugs for a single binding site. These observations prompted us to evaluate the possibility that diphenylhydantoin was not acting at (and therefore not competing for) the same channel binding site as amitriptyline. Experiments altering pHi and pHo revealed dramatic differences between amitriptyline and diphenylhydantoin. When pHo was increased from 7.4 to 8.0, tau r was reduced approximately threefold (from 13.6 +/- 3.2 to 4.2 +/- 0.1 seconds, p less than 0.0001) during exposure to amitriptyline, but no effect was seen on tau r after exposure to diphenylhydantoin. Conversely, when pHi was increased from 7.3 to 8.0, tau r after amitriptyline was unaffected, but tau r after diphenylhydantoin markedly increased (from 0.71 +/- 0.21 to 2.60 +/- 1.30 seconds, p less than 0.001). Additionally, diphenylhydantoin block demonstrated profound voltage dependence across the range of -130 to -90 mV, whereas amitriptyline block appeared less voltage sensitive. Single-channel studies using patch-clamp techniques in isolated ventricular myocytes supported these data.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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90.
Using the extremely sensitive technique of polymerase chain reaction (PCR) to detect the bcl-2 translocation, only 50% of bone marrows could be purged of PCR-detectable lymphoma cells using a cocktail of three anti-B-cell monoclonal antibodies (MoAbs) and complement-mediated lysis. This observation is of clinical importance because those patients whose reinfused marrows harbored residual lymphoma cells showed a significantly increased incidence of relapse. To improve purging, we used PCR detection of the bcl-2 translocation to compare the efficiency of complement-mediated lysis with immunomagnetic bead depletion. Using either a three or a four MoAb cocktail followed by immunomagnetic bead depletion, all PCR-detectable cells were purged after three cycles of treatment. In these same patient samples, treatment with three MoAbs and complement purged only 11 of the 25 (44%) samples. The addition of a fourth MoAb followed by complement lysis purged the marrows of only an additional five patients. Immunomagnetic bead depletion was specific because there was no loss of committed myeloid progenitor cells. The above results suggest that immunomagnetic bead depletion of the harvested marrow will likely be superior to our previous method of purging and the lack of nonspecific toxicity to myeloid progenitor cells predicts that it will not impair engraftment. This methodology will now be used to determine whether the reinfusion of lymphoma free marrow affects the incidence of relapse after autologous bone marrow transplantation.  相似文献   
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