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排序方式: 共有6339条查询结果,搜索用时 31 毫秒
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2.
Antony E. Shrimpton Robert L. Schelper Reinhold P. Linke John Hardy Richard Crook Dennis W. Dickson Takashi Ishizawa Richard L. Davis 《Neuropathology》2007,27(3):228-232
Over 100 mutations in the presenilin‐1 gene (PSEN1) have been shown to result in familial early onset Alzheimer disease (EOAD), but only a relatively few give rise to plaques with an appearance like cotton wool (CWP) and/or spastic paraparesis (SP). A family with EOAD, seizures and CWP was investigated by neuropathological study and DNA sequencing of the PSEN1 gene. Aβ was identified in leptomeningeal vessels and in cerebral plaques. A single point mutation, p.L420R (g.1508T > G) that gives rise to a missense mutation in the eighth transmembrane (TM8) domain of PS1 was identified in two affected members of the family. p.L420R (g.1508T > G) is the mutation responsible for EOAD, seizures and CWP without SP in this family. 相似文献
3.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
4.
Thomas G. Hardy Jr. M.D. Pedro S. Aguilar M.D. Dr. William R. C. Stewart M.D. 《Diseases of the colon and rectum》1989,32(6):528-532
Three patients with complete colonic obstruction treated by primary resection and anastomosis with intraoperative colon tube decompression and bowel lumen sterilization without a protective colostomy are presented. An improved colonic decompressor was used. It is postulated that this procedure is an alternative safe technique in patients with colonic obstruction in whom an end-colostomy, mucous fistula, or Hartmann pouch would be necessary. 相似文献
5.
6.
Stefan Ockert Hardy Schumacher Dittmar Böckler Katrin Malcherek Jochen Hansmann Jens Allenberg 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):725-730
Background and aims Since the introduction of endovascular aortic aneurysm repair (EVAR) for aortic aneurysms, the number of juxtarenal aortic
aneurysms (JRA) has been growing steadily due to selection bias (neck morphology for EVAR). This case-match study compares
the perioperative outcome and midterm results of suprarenally clamped JRA with infrarenal aortic aneurysms (AAA).
Methods From 1997 to 2004, patients who received open surgery with suprarenal clamping for JRA were included in the study and compared
to matched patients with infrarenal clamping (AAA). Measurements analyzed were the in-hospital mortality and morbidity. Midterm
results were obtained through clinical investigation and magnetic resonance angiography imaging.
Results Thirty-five patients (mean age, 68.4 years; 30 male and 5 female) received suprarenal cross-clamping for JRA. The overall
in-hospital mortality for JRA and for the controls (AAA) with elective aortic repair was 4.5% (6.1% JRA; 3% AAA, p = 0.058). The morbidity of JRA was elevated according to the rate of pulmonary complications (p = 0.021) and the need for re-operation (p = 0.019). The mean follow-up time was 2.3 years (range, 8–96 months). At follow-up, 28 patients (80%) from the JRA group
and 29 patients from the AAA group (82.9%) were alive.
Conclusion Open aortic surgery for JRA with the need for suprarenal cross-clamping shows a slightly elevated in-hospital mortality rate
without statistical significance and equal midterm mortality results in comparison with infrarenally clamped aortic aneurysms. 相似文献
7.
Scalp electrical recording during paralysis: quantitative evidence that EEG frequencies above 20 Hz are contaminated by EMG. 总被引:2,自引:0,他引:2
Emma M Whitham Kenneth J Pope Sean P Fitzgibbon Trent Lewis C Richard Clark Stephen Loveless Marita Broberg Angus Wallace Dylan DeLosAngeles Peter Lillie Andrew Hardy Rik Fronsko Alyson Pulbrook John O Willoughby 《Clinical neurophysiology》2007,118(8):1877-1888
OBJECTIVE: To identify the possible contribution of electromyogram (EMG) to scalp electroencephalogram (EEG) rhythms at rest and induced or evoked by cognitive tasks. METHODS: Scalp EEG recordings were made on two subjects in presence and absence of complete neuromuscular blockade, sparing the dominant arm. The subjects undertook cognitive tasks in both states to allow direct comparison of electrical recordings. RESULTS: EEG rhythms in the paralysed state differed significantly compared with the unparalysed state, with 10- to 200-fold differences in the power of frequencies above 20 Hz during paralysis. CONCLUSIONS: Most of the scalp EEG recording above 20 Hz is of EMG origin. Previous studies measuring gamma EEG need to be re-evaluated. SIGNIFICANCE: This has a significant impact on measurements of gamma rhythms from the scalp EEG in unparalysed humans. It is to be hoped that signal separation methods will be able to rectify this situation. 相似文献
8.
Dittmar Böckler Hardy Schumacher Klaus Klemm Marcel Riemensperger Philipp Geisbüsch Drosos Kotelis Harry Rotert Jens-Rainer Allenberg 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):715-723
OBJECTIVES: to report our experience with hybrid vascular procedures in patients with pararenal and thoracoabdominal aortic pathologies. METHODS: 68 patients were treated for thoracoabdominal aortic pathologies between October 1999 and February 2004; 19 patients (16 men; mean age 68, range 40-79) with high risk for open thoracoabdominal repair were considered to be candidates for combined endovascular and open repair. Aortic pathologies included five thoracoabdominal Crawford I aneurysms, one postdissection expanding aneurysm, three symptomatic plaque ruptures (Crawford IV), five combined thoracic descending and infrarenal aneurysms with a healthy visceral segment, three juxtarenal or para-anastomotic aneurysms, and two patients with simultaneous open aortic arch replacement and a rendezvous maneuver for thoracic endografting. Commercially available endografts were implanted with standardized endovascular techniques after revascularization of visceral and renal arteries. RESULTS: Technical success was 95%. One patient developed a proximal type I endoleak after chronic expanding type B dissection and currently is waiting conversion. Nine patients underwent elective, five emergency and five urgent (within 24 h) repair. 17 operations were performed simultaneously, and 2 as a staged procedure. Postoperative complications include two retroperitoneal hemorrhages, and one patient required long-term ventilation with preexisting subglottic tracheal stenosis. Thirty-day mortality was 17% (one multiple organ failure, one secondary rupture after open aortic arch repair, one myocardial infarction). Paraplegia or acute renal failure were not observed. Total survival rate was to 83% with a mean follow-up of 30 months. CONCLUSIONS: Midterm results of combined endovascular and open procedures in the thoracoabdominal aorta are encouraging in selected high risk patients. Staged interventions may reduce morbidity. 相似文献
9.
The Medical Research Council UKALL V trial for children with standard-risk acute lymphoblastic leukemia (ALL) (aged 1 to 14 years, leucocyte count less than 20 X 10(9)/L) was designed to determine whether the immunosuppressive effects of treatment could be reduced without sacrifice of antileukemic effect by alterations in the type of continuing therapy or in fractionation of cranial irradiation. Remission was achieved in 496 children on standard induction therapy, and 309 children received 24 Gy of cranial irradiation in ten to 16 fractions over 21 days, and 174 received 21 Gy in five to nine fractions over 21 days. The type of radiotherapy administered had no influence on relapse at any site or rate of death in remission. All 496 children were randomized to receive chemotherapy for 2 or 3 years with 6-mercaptopurine and methotrexate either as a continuous (group C) or a semicontinuous (group G) regimen or as a five-day pulse every 3 weeks (group I). All groups also received vincristine and prednisolone every 6 weeks. With a minimum follow-up of almost 7 years, patients in group I had significantly fewer remission deaths (P = .025) but a much higher rate of bone marrow relapse than those in group C or G (P = .002). There was an overall benefit for 3 years of chemotherapy compared with 2 years, which in contrast to previous studies, was more apparent in girls and in patients in groups C and G. Testicular relapse occurred in 37 boys, including 19 patients off therapy, with a previously negative biopsy. The overall results confirmed the prognostic significance of initial leucocyte count, even among these standard-risk patients, while girls had a superior rate of disease-free survival, but not of hematologic remission. It is concluded that, even among standard-risk patients, the prognosis is influenced by the height of the initial leukocyte count. While alterations in the fractionation of cranial irradiation do not appear to have influenced disease-free survival, intermittent continuing chemotherapy, although less immunosuppressive, is less effective than conventional continuous therapy in the treatment of ALL. In this study, 3 years of chemotherapy appeared superior to 2 years. 相似文献
10.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed
and treated with antibiotics. OBJECTIVE: This study aimed to determine the
evidence for the effectiveness of antibiotic treatment in acute maxillary
sinusitis in adults by assessing the methodological quality of
placebo-controlled double-blind randomized trials. METHOD: An evaluation by
four raters through a 35-item scoring-scale for internal and external
validity of all placebo-controlled double-blind randomized trials on acute
sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five
trials were excluded because they were not placebo-controlled,
double-blind, randomized, or were carried out in patients with chronic
sinusitis or in children. The three remaining trials were performed in
different populations (one in general practice) between 1973 and 1978. Only
one study claimed superiority of antibiotic treatment. Different inclusion
criteria and major outcome measures were used by the authors. The
reliability of major outcome events was reported poorly or not at all and
in two studies outcome measures were clinically inappropriate. The studies
scored 30-62% of the maximum attainable score for internal validity and
10-20% for external validity. CONCLUSION: The effectiveness of antibiotic
treatment in acute maxillary sinusitis in a general practice population is
not based sufficiently on evidence.
相似文献