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81.
82.
Michele L Ries Britta M Jabbar Taylor W Schmitz Mehul A Trivedi Carey E Gleason Cynthia M Carlsson Howard A Rowley Sanjay Asthana Sterling C Johnson 《Journal of the International Neuropsychological Society》2007,13(3):450-461
Awareness of cognitive dysfunction shown by individuals with Mild Cognitive Impairment (MCI), a condition conferring risk for Alzheimer's disease (AD), is variable. Anosognosia, or unawareness of loss of function, is beginning to be recognized as an important clinical symptom of MCI. However, little is known about the brain substrates underlying this symptom. We hypothesized that MCI participants' activation of cortical midline structures (CMS) during self-appraisal would covary with level of insight into cognitive difficulties (indexed by a discrepancy score between patient and informant ratings of cognitive decline in each MCI participant). To address this hypothesis, we first compared 16 MCI participants and 16 age-matched controls, examining brain regions showing conjoint or differential BOLD response during self-appraisal. Second, we used regression to investigate the relationship between awareness of deficit in MCI and BOLD activity during self-appraisal, controlling for extent of memory impairment. Between-group comparisons indicated that MCI participants show subtly attenuated CMS activity during self-appraisal. Regression analysis revealed a highly significant relationship between BOLD response during self-appraisal and self-awareness of deficit in MCI. This finding highlights the level of anosognosia in MCI as an important predictor of response to self-appraisal in cortical midline structures, brain regions vulnerable to changes in early AD. 相似文献
83.
Magainin 1 and magainin 2, originally isolated from African clawed frog Xenopus laevis skin, inhibit the growth of bacteria and fungi. Synthetic magainin A (MAG A) and magainin G (MAG G) are more potent against bacteria and protozoa. In order to determine the antitumor activity of these analogues, we have tested these two analogues against six small cell lung cancer (SCLC) cell lines NCI-H82, NCI-H526, NCI-H678, NCI-H735, NCI-H841, and NCI-H889, which were known to differ by more than 10-fold in their sensitivity to different chemotherapeutic agents, and four normal human fibroblast cell lines. Semiautomated 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays of the six SCLC cell lines revealed average concentrations producing 50% inhibition (IC50) values of 2.6 microM (range, 0.49-9.30 microM) for cisplatin, 2.5 microM (range, 0.39-6.00 microM) for etoposide, and 138.8 nM (range, 55.0-450.0 nM) for doxorubicin. The average IC50 of MAG A was 8.64 microM (range, 6.23-11.7 microM) and that of MAG G was 8.82 microM (range, 4.44-12.5 microM) against the SCLC cell lines. Despite a 10-fold difference in sensitivity to standard chemotherapeutic agents, the IC50 of MAG A and MAG G differs by less than 3-fold. The average IC50 against four normal human fibroblast cell lines was 21.1 microM (range, 12.7-25.6 microM) for MAG A and 29.2 microM (range, 21.3-34.8 microM) for MAG G. Combined exposure to the IC50 concentration of MAG A or MAG G plus IC50 of etoposide or cisplatin decreased the percentage of surviving SCLC cells to 29.0% (range, 26.1-31.7%). MAG A or MAG G had an additive effect when used with standard chemotherapeutic agents. These data suggest that MAG A and MAG G have in vitro antitumor activity against SCLC cell lines. 相似文献
84.
The human squamous carcinoma-reactive murine monoclonal antibody PF1/D was used to derive a conjugate with the Vinca derivative 4-desacetylvinblastine-3-carboxyhydrazide (PF1/D-DAVLBHYD). This immunoconjugate was shown to be largely aggregate free and there was no loss of immunoreactivity postconjugation. When tested in vivo in a 3-day-established human squamous carcinoma nude mouse xenograft model, the PF1/D-DAVLBHYD conjugate eliminated tumor growth with three injections (days 3, 6, and 9) at 2 mg/kg Vinca content. Significant tumor suppression was also observed with 0.5 mg/kg conjugate doses. In contrast, free PF1/D antibody had minimal antitumor activity and no activity was seen with identical doses of a control non-tumor-binding IgG-DAVLBHYD conjugate. Together, these data demonstrate the specificity of the PF1/D-DAVLBHYD antitumor effects. 相似文献
85.
86.
C W Pinson R R Lopez K G Benner E B Keeffe M K Porayko A W Sasaki D K Bowers L J Wheeler R G Lee R S Johnson 《American journal of surgery》1991,161(5):606-611
During the first 24 months of the Oregon Liver Transplantation Program, which began in October 1988, 94 patients were formally evaluated and 47 adults underwent 54 liver transplantations. Thirty-four percent of patients were veterans. The recipient operation lasted a mean of 7.4 hours (range: 4 to 16 hours). Veno-venous bypass was used routinely at first but selectively later (7 of the last 26 cases), resulting in reduced operating time. Hepatic artery reconstruction was end-to-end anastomosis in 52 cases and iliac conduit in 2. No arterial thrombosis occurred. Biliary reconstruction was choledochocholedochostomy in 83% and choledochojejunostomy in 17%. Biliary complications occurred in 28%. Operative mortality was 2%, and 1-year actual survival was 80%. Patients with hepatitis B fared worse, with four of six dying at a mean of 7.6 months. Overall, the median hospital stay was 30 days. Patients surviving more than 3 months had a mean Karnofsky score of 82%. No significant difference in outcome was noted in patients receiving prophylactic OKT3 monoclonal antibody (used in 45%) versus conventional immunosuppressive therapy. Overall, allograft rejection occurred in 55% of patients. Retransplantation was required in seven patients, three for primary graft nonfunction, two for uncontrolled rejection during induction therapy with OKT3, and two for graft failure secondary to recurrent hepatitis B. 相似文献
87.
D R Johnson 《Delaware medical journal》1991,63(5):317-318
88.
Strut fixation of an extensive flail chest 总被引:2,自引:0,他引:2
R J Landreneau J M Hinson S R Hazelrigg J A Johnson T M Boley J J Curtis 《The Annals of thoracic surgery》1991,51(3):473-475
The indications for and preferred approaches to operative stabilization of posttraumatic chest wall instability are uncertain. We suggest this simple, rapid, and effective approach to surgical stabilization by Luque rod strutting of the flail segment when operation is required. 相似文献
89.
S F Johnson S B Johnson W E Strodel D E Barker P A Kearney 《The Journal of trauma》1991,31(11):1546-1550
Proximal upper extremity (subclavian and axillary) vascular injury (SAVI) and brachial plexus injury (BPI) occur uncommonly. However, BPI may be associated with SAVI and frequently is an important determinant of long-term disability. The medical records of patients with traumatic SAVI, BPI, or both over a 5-year period were reviewed. A total of 31 patients were identified. The group was predominantly male (28 men/3 women) with a mean age of 30.5 +/- 1.8 years (range, 15-63 years). Blunt trauma accounted for 43.5% of SAVI cases and 77.8% of BPI cases. Thirteen patients (41.9%) sustained SAVI alone (group I), 10 patients (32.2%) had combined SAVI and BPI (group II), and 8 patients (25.9%) had BPI alone (group III). Subclavian and axilliary vascular injury occurred in 10 of 18 patients (55.6%) with a BPI. Brachial plexus injury occurred in 10 of 23 patients (43.5%) with a SAVI. Patients with SAVI from blunt trauma were significantly more likely to have an associated complete BPI than patients with penetrating trauma. All patients with a complete BPI (6 patients) had an associated SAVI regardless of mechanism of injury. Only one patient with a partial BPI from blunt trauma had an associated SAVI. The Injury Severity Score was significantly higher for patients in group II. An average of 2.8 and 3.3 associated injuries were observed in patients with SAVI (groups I and II) versus patients without SAVI (group III), respectively. No patient who had a complete BPI showed an improvement in neurologic status during a mean follow-up of 7.2 months. No late vascular sequelae occurred in group-III patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
90.
Nine patients have undergone single-stage radical cystectomy and ileal conduit urinary diversion two to fifty-one months after coronary artery bypass procedures. Two patients presenting with intractable angina at the time their malignant disease was being evaluated required bypass surgery before cystectomy could be undertaken. No significant cardiac morbidity occurred postoperatively, and all remain alive without evidence of malignant disease. 相似文献