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1.
Slowly progressive aphasia without generalized dementia: studies with positron emission tomography 总被引:14,自引:0,他引:14
J B Chawluk M M Mesulam H Hurtig M Kushner S Weintraub A Saykin N Rubin A Alavi M Reivich 《Annals of neurology》1986,19(1):68-74
Slowly progressive aphasia without generalized dementia is a degenerative syndrome selectively affecting dominant hemisphere language areas. We report changes in regional glucose metabolism measured by positron emission tomography in two patients with this condition. Striking abnormalities of glucose utilization in the left cerebral cortex were demonstrated in both patients. The findings of other neurodiagnostic studies were relatively unremarkable. The first patient had a 3-year history of progressive anomia and impaired auditory verbal recall. An electroencephalogram was normal, and computed tomography showed mild left perisylvian atrophy. Positron emission tomography revealed profound hypometabolism in the left temporal regions. The second patient also had a 3-year history of progressive anomia. Electroencephalography, computed tomography, and magnetic resonance imaging scans were normal. Positron emission tomography showed a major reduction in left parietal glucose utilization, with a lesser decrement in left temporal metabolism. Neither patient demonstrated significant contralateral or global abnormalities such as those reported in positron emission tomographic studies of Alzheimer's disease with or without focal clinical features. These observations support the concept of adult-onset progressive aphasia without dementia as a clinical syndrome distinct from Alzheimer's disease. 相似文献
2.
Leslee J. Shaw Romalisa Miranda-Peats Piotr Slomka John Friedman Sean W. Hayes Daniel S. Berman Gary V. Heller Marcin Dada William E. Boden Paul Casperson Robert A. O’Rourke Ronald Schwartz William S. Weintraub David J. Maron Spencer King Koon Teo Pamela Hartigan 《Journal of nuclear cardiology》2006,13(5):685-698
Background Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after
intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical
outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial.
Methods and Results The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical
therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been
designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia
at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship
between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate
the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization
patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic
intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive
risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization
in reducing patients’ ischemic burdens.
Conclusions The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology.
We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based
management of patients with stable coronary disease.
The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research
and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained
from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data
Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon;
and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional
funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research
from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging. 相似文献
3.
Fabia Preminger Patrice L Weiss Naomi Weintraub 《The American journal of occupational therapy》2004,58(2):193-201
PURPOSE: To determine whether there is a correlation between handwriting and keyboarding speed and accuracy, and whether handwriting and keyboarding share common underlying components. METHODS: Sixty-three typically developing 5th-grade students attended a series of 15 keyboarding lessons for a total of 5 hours. Prior to the lessons, cognitive, sensory, and motor skills related to handwriting were evaluated. Prior to and following the lessons keyboarding and handwriting accuracy and speed were also tested. Correlations were employed to examine relationships between handwriting and keyboarding skills and multiple regression analyses were used to examine the contribution of performance components to handwriting and keyboarding performance. RESULTS: Following keyboarding instruction, a significant correlation was found between handwriting and keyboarding speed, but not in accuracy of these tasks. Similarly, some of the specific tests measuring tactile and oculo-motor functions were found to be related to both handwriting and keyboarding speed, yet accuracy of these tasks did not share common underlying components. CONCLUSIONS: It appears that handwriting and keyboarding accuracy may entail different skills, suggesting that keyboarding may be a potential alternative writing tool for students with handwriting difficulties. It also appears that when students write slowly, handwriting speed should be considered prior to recommending keyboarding for these students. Additional research is required to further support these findings. 相似文献
4.
R W Lash R K Desai C A Zimmerman M R Flack T Yoshida F E Wondisford B D Weintraub 《Journal of endocrinological investigation》1992,15(4):255-263
In recent studies, site-directed mutagenesis has been used to alter the tripeptide glycosylation recognition sequences of glycoprotein hormone subunits, thereby affecting their structure and function. However, it is not known whether these effects result from changes in glycosylation status, amino acid sequence, or both. We therefore studied the synthesis of wild-type and mutant recombinant human thyrotropins produced by transient transfection of a human cell line. Mutating the TSH-beta subunit glycosylation recognition sequence, Asn-Thr-Thr (codons 23-25), to either Gln-Thr-Thr or Asn-Thr-Tyr abolished subunit glycosylation, as demonstrated by the inability to incorporate 3H-carbohydrates. However, a third mutation (Asn-Thr-Ser) contained an intact glycosylation recognition sequence site, and was shown to retain glycosylation. The mutations that abolished TSH-beta subunit glycosylation resulted in greater than 90% decreases in TSH synthesis. However, the glycosylation recognition sequence mutant that retained beta subunit glycosylation exhibited a 70% decrease in TSH production. These decreases were not attributable to the intracellular accumulation of TSH or its free beta subunit. We also engineered two TSH-beta subunit mutations that did not alter the glycosylation recognition sequence. A glycine to arginine mutation adjacent to the glycosylation recognition sequence, in a region thought to be critical for heterodimer formation, abolished TSH production. In contrast, shortening the TSH-beta subunit carboxyterminus by six amino acids increased TSH synthesis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Management of adult sarcomas of the bladder and prostate 总被引:7,自引:0,他引:7
Historically, survival of patients with adult pelvic sarcoma of the bladder and prostate has been poor. Between November 1974 and November 1984 we treated 11 patients with leiomyosarcoma: 7 with primary bladder and 4 with prostate tumors. Patients with nonbulky disease underwent surgical resection and were observed if the margins and nodes were negative. Patients with positive surgical margins or nodes were treated adjunctively with external beam radiotherapy, 4,500 to 5,000 rad, and chemotherapy. Patients with bulky disease were treated with preoperative chemotherapy with or without radiotherapy followed by an exenterative operation. Of the 11 patients 9 are without evidence of disease with a mean followup of 61 months (range 35 to 96 months). One patient was lost to followup after 4 months and 1 died of disease after 11 months. Three patients with rhabdomyosarcoma were treated and 1 had no evidence of disease 24 months after therapy. Two patients died at 4 and 18 months. 相似文献
6.
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8.
Patrick Ambrosetti Karim Francis Dominique Weintraub Jonathan Weintraub 《Journal of gastrointestinal surgery》2007,11(6):767-772
We performed a prospective study to analyze the functional results following elective laparoscopic sigmoidectomy for computed
tomography (CT)-proven diagnosis of acute diverticulitis and review the literature. Forty-three of 45 available patients (96%)
who had laparoscopic sigmoidectomy for CT-proven acute diverticulitis answered, after a mean time of 40 months, a questionnaire
exploring new abdominal symptoms, bowel function, and the patient’s own judgement of the surgical outcome. Surgical technique
aimed at removing all the sigmoid by taking down the splenic flexure and do a colorectal anastomosis. Four patients (9%) complained
of new abdominal pain. Bowel function was reported as better for 24 patients (56%), unchanged for 16 patients (37%), and worse
for 3 (7%). Twenty patients (47%) considered their final result as excellent to good, 17 patients (40%) as satisfying, and
6 patients (13%) as mediocre. Male gender, absence of preoperative history compatible with an irritable bowel syndrome, length
of resected sigmoid and residual acute inflammation on histology are statistically predictive of a better postoperative degree
of satisfaction. After elective laparoscopic sigmoidectomy for CT-proven diverticulitis, a great majority of patients are
very satisfied with their postoperative general comfort. 相似文献
9.
Michael V. Hansen Helen Holmgren Anders Spberg Andrej Warycha 《Neurourology and urodynamics》1990,9(3):257-268
EMG responses in the external anal sphincter (EAS), the rectus abdominis muscle (RA), and the anterior tibial muscle (TA) were recorded following single magnetic transcranial cortical stimulations (TCCS) in seven healthy volunteers. The responses in the EAS differed from the responses in the other muscles. They had comparatively long durations ranging from 1 to 2 seconds, no inhibitory periods were observed, and there was no tendency for habituation to occur following a limited number of stimuli. The responses recorded in the EAS were used as test responses in order to evaluate the excitability changes in the EAS motoneurons occurring during bladder filling. Cystometries with filling rates of 15, 50 and 200 ml/min were done. During these cystometries TCCS were applied repeatedly, with constant strength, after each 50 ml of filling up to bladder capacity. The responses following TCCS changed in a highly reproducible way during bladder filling. After 100–200 ml of filling, the responses had longer latencies, diminished sizes, and shorter durations. When the filling reached a level 50–150 ml below capacity, the responses in most subjects again became greater and the latencies shorter. The changes were believed to be physiological. It was concluded that the EAS motoneurons are under both inhibitory and facilitatory influence during bladder filling in intact healthy humans. Facilitatory influences are often observed when the bladder is filled close to capacity. At lower bladder volumes the observed influence is always inhibitory. A decrease in the EMG activity of the EAS during filling cystometry should consequently not be regarded as a pathological response. 相似文献
10.
R G Weintraub W J Brawn A W Venables R B Mee 《The Journal of thoracic and cardiovascular surgery》1990,99(2):320-326
Before January 1987, 62 infants underwent two-patch repair of complete (51) or intermediate (11) atrioventricular septal defect at the Royal Children's Hospital, Melbourne. Median age at repair was 4.3 months and median weight was 4.4 kg. Early deaths (3%) were confined to two infants with preoperative respiratory tract infections; a further two patients died during follow-up (late mortality rate 3%). Reoperation for severe postoperative mitral regurgitation was necessary in 10 infants (16%), two of whom subsequently required mitral valve replacement with a prosthesis. Preoperative atrioventricular valve regurgitation was assessed retrospectively in 49 patients from angiography or Doppler echocardiography and was found to be absent or mild in 33 (68%), moderate in 9 (18%), and severe in 7 (14%). At the time of latest review (at a mean of 2.4 years after repair), judged from a combination of clinical and echocardiographic criteria, mitral regurgitation was absent or mild in 49 (84%) of the 58 survivors; none of them had symptomatic regurgitation or were requiring continuing medical treatment. Analysis of sequential atrioventricular valve function in 46 of the 49 patients in whom objective preoperative data were available showed no relationship between the degree of preoperative and postoperative atrioventricular valve regurgitation. Infants without Down's syndrome, however, had a significantly higher reoperation rate for severe postoperative mitral valve regurgitation (50%) than those with Down's syndrome (10%) (p = 0.007). Complete atrioventricular septal defect can be repaired in early infancy with a low mortality rate and good intermediate term results. 相似文献