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241.
SW Atlas L Sheppard HI Goldberg RW Hurst J Listerud E Flamm 《Canadian Metallurgical Quarterly》1997,203(3):807-814
PURPOSE: To assess magnetic resonance (MR) angiography for the detection and characterization of angiographically proved intracranial aneurysms by using an advanced method of postprocessing, in a blinded-reader study. MATERIALS AND METHODS: One hundred fifty-eight vessels were examined with catheter angiography and three-dimensional time-of-flight MR angiography in 44 patients with 63 aneurysms and 15 patients with no aneurysm at catheter angiography. Postprocessing was performed off-line with an advanced multifeature-extraction, ray-tracing algorithm. MR angiograms were interpreted independently by three neuroradiologists blinded to the catheter angiographic results for presence, location, size, and morphology of the aneurysm. Proof of diagnosis was consensus reading of catheter angiograms. RESULTS: Mean sensitivity for detection of aneurysms was 75% (range, 70%-79%). As a screening tool (ie, detection of at least one aneurysm necessitating catheter angiography), mean sensitivity was 91% for all aneurysms and 95% for aneurysms larger than 3 mm. This method was not adequate for detection of lobulation or size of aneurysm. CONCLUSION: MR angiography with an advanced method of postprocessing can result in highly sensitive, specific studies for the diagnosis of intracranial aneurysms that are of sufficient size to be considered for surgical treatment, but it is inadequate for characterization of aneurysms. 相似文献
242.
CI Rivas JC Vera F Delgado-López ML Heaney VH Guaiquil RH Zhang HI Scher II Concha F Nualart C Cordon-Cardo DW Golde 《Canadian Metallurgical Quarterly》1998,91(3):1037-1043
This investigation examined the effects of NaHCO3 loading on lactate concentration ([La]), acid-base balance, and performance for a 603. 5-m sprint task. Ten greyhounds completed a NaHCO3 (300 mg/kg body weight) and control trial in a crossover design. Results are expressed as means +/- SE. Presprint differences (P < 0.05) were found for NaHCO3 vs. control, respectively, for blood pH (7.47 +/- 0.01 vs. 7.42 +/- 0.01), HCO-3 (28.4 +/- 0.4 vs. 23.5 +/- 0.3 meq/l), and base excess (5.0 +/- 0.3 vs. 0.2 +/- 0.3 meq/l). Peak blood [La] increased (P < 0.05) in NaHCO3 vs. control (20.4 +/- 1.6 vs. 16.9 +/- 1.3 mM, respectively). Relative to control, NaHCO3 produced a greater (P < 0.05) reduction in blood base excess (-18.5 +/- 1.4 vs. -14.1 +/- 0.8 meq/l) and HCO-3 (-17.4 +/- 1.2 vs. -12.8 +/- 0.7 meq/l) from presprint to postexercise. Postexercise peak muscle H+ concentration ([H+]) was higher (P < 0.05) in NaHCO3 vs. control (158.8 +/- 8.8 vs. 137.0 +/- 5.3 nM, respectively). Muscle [H+] recovery half-time (7.2 +/- 1.6 vs. 11.3 +/- 1.6 min) and time to predose values (22.2 +/- 2.4 vs. 32.9 +/- 4.0 min) were reduced (P < 0.05) in NaHCO3 vs. control, respectively. No differences were found in blood [H+] or blood [La] recovery curves or performance times. NaHCO3 increased postexercise blood [La] but did not reduce the muscle or blood acid-base disturbance associated with a 603.5-m sprint or significantly affect performance. 相似文献
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JI Diaz SV Nicosia J Szakacs J Powsang HI Saba 《Canadian Metallurgical Quarterly》1996,23(1-2):165-171
Although most common, malignant lymphoma and Kaposi's sarcoma are not the only malignancies encountered in lymph nodes from HIV-infected patients. An increased frequency of testicular germ cell tumors in HIV-infected individuals has been reported. We report here the first case, to our knowledge, of a metastatic seminoma in an HIV-infected hemophiliac. The atypical clinical presentation, cervical and axillary adenopathy, simulated malignant lymphoma. The diagnosis was first suspected when a fine needle aspiration biopsy from an enlarged cervical node revealed a mixture of benign appearing lymphocytes and loosely cohesive large tumor cells in a "tigroid" background. Immunocytochemistry and a subsequent excisional biopsy confirmed the cytologic diagnosis. Metastatic germ cell tumors should be considered in the differential diagnosis of HIV-related lymphadenopathy. 相似文献
245.
AJ Roth AB Kornblith L Batel-Copel E Peabody HI Scher JC Holland 《Canadian Metallurgical Quarterly》1998,82(10):1904-1908
BACKGROUND: As more oncology care is moved to the outpatient setting, the need for a rapid means for oncologists to identify patients with significant distress has increased. Concurrent with this move has been the pressure to reduce time spent with each patient, adding to the likelihood that a distressed patient will not be recognized and will remain untreated in the current health care environment. METHODS: A pilot program was conducted in a prostate carcinoma oncology clinic to test the feasibility of a two-stage approach that identifies patients in significant distress and refers them for treatment. Two pencil and paper self-report measures were used to detect psychologic distress in patients over the previous week: 1) The Hospital Anxiety and Depression Scale (HADS) and 2) "The Distress Thermometer." Patients who scored above an agreed upon cutoff score on either measure (HADS = 15+; Thermometer = 5+) were referred to the psychiatric liaison in the clinic for evaluation. RESULTS: Compliance in filling out the measures was excellent; only 8 of 121 patients (6.6%) refused. Thirty-one percent of evaluable patients were referred based on elevated scores. Seventeen of 29 patients actually were evaluated. Eight of 17 patients met Diagnostic and Statistical Manual (of Mental Disorders)-IV criteria for a psychiatric disorder. CONCLUSIONS: This approach for rapid screening for distress was acceptable in prostate carcinoma patients, although these older men were reluctant to agree to evaluation and treatment. This simple screening method needs further testing and the identification of barriers on the part of the patient and oncologist that impede the identification of the most distressed patients. 相似文献
246.
BACKGROUND: Significant controversy exists concerning how best to reverse excessive anticoagulation (due to warfarin sodium therapy) with phytonadione (vitamin K1) while avoiding overcorrection in patients who need to have anticoagulation therapy maintained. METHODS: A retrospective review of phytonadione use in reversing excessive anticoagulation was performed in 3 institutions. The effectiveness of low-dose (< or =0.5 mg) intravenous (LDIV), high-dose (1-10 mg) intravenous (HDIV), subcutaneous (1-10 mg) (SC), and oral (2.5 or 5 mg) (PO) phytonadione was evaluated within 48 hours of administration. Anticoagulation correction (international normalized ratio [INR], > or =2.0 and < or =5.0) occurred in 5 of 8 patients in the LDIV, 5 of 9 in the HDIV, 7 of 10 in the SC, and 5 of 6 in the PO groups. Correction was inadequate (INR >5.0) in 2 of 8 patients in the LDIV, 0 of 9 in the HDIV, 3 of 10 in the SC, and 1 of 6 in the PO groups. Overcorrection (INR <2.0) occurred in 1 patient in the LDIV, 4 patients in the HDIV, 0 in the SC, and 0 in the PO groups. CONCLUSIONS: Anticoagulation correction was achieved in most patients in all 4 groups. The HDIV method was most effective in lowering the INR to less than 5.0, but overcorrection occurred more frequently (4 patients in the HDIV vs 1 patient in the LDIV and 0 patients in the SC and PO groups). Failure to achieve an INR of less than 5.0 was a greater problem in the SC group (3 patients in the SC vs 2 patients in the LDIV and 1 patient in the PO groups). The LDIV and PO methods appear to be acceptable alternatives to the HDIV and SC methods currently recommended. 相似文献
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KA Chianese-Bullock HI Russell C Moller W Gerhard JJ Monaco LC Eisenlohr 《Canadian Metallurgical Quarterly》1998,161(4):1599-1607
The factors that influence the intracellular location(s) of MHC class II-restricted epitope loading remain poorly understood. We present evidence that two I-Ed-restricted epitopes of the influenza hemagglutinin (HA) molecule, termed site 1 (S1; encompassing amino acid residues 107-119) and site 3 (S3; encompassing amino acid residues 302-313), are generated in distinct endocytic compartments. By means of an epitope-specific mAb, we show that S1 becomes detectable in late endocytic/lysosomal vesicles; using a mutant cell line, we also show that the presentation of S1 is dependent upon H2-DM expression. In contrast, S3; presentation is H2-DM-independent and appears in early endosomes as a result of acid-induced structural changes in HA. Presentation of both epitopes can be made H2-DM-independent by denaturing HA and made H2-DM-dependent by preventing the acid-induced conformational changes from occurring. These findings indicate that the structural context of a given epitope can determine where it is processed. 相似文献
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