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101.
The reproducibility of quantitative cerebral blood flow (CBF) measurements using MRI with arterial spin labeling and acetazolamide challenge was assessed in 12 normal subjects, each undergoing the identical experimental procedure on two separate days. CBF was measured on a 1.5T scanner using a flow-sensitive alternating inversion recovery (FAIR) pulse sequence, performed both at baseline and 12 min after intravenous administration of acetazolamide. T(1) was measured in conjunction with the FAIR scan in order to calculate quantitative CBF. The CBF maps were segmented to separate gray matter (GM) from white matter (WM) for region-of-interest (ROI) analyses. Post- acetazolamide CBF values (ml/100 g/min, mean +/- SD) of 87.5 +/- 12.5 (GM) and 46.1 +/- 10.8 (WM) represented percent increases of 37.7% +/- 24.4% (GM) and 40.1% +/- 24.4% (WM). Day-to-day differences in baseline CBF were -1.7 +/- 6.9 (GM) and -1.4 +/- 4.7 (WM) or, relative to the mean CBF over both days for each subject, -2.5% +/- 11.7% (GM) and -3.8% +/- 13.6% (WM) Day- to-day differences in absolute post-ACZ CBF increase were -2.5 +/- 6.8 (GM) and 2.7 +/- 9.4 (WM) or, relative to the mean CBF increase over both days for each subject, -4.7% +/- 13.3% (GM) and 9.1% +/- 26.2% (WM). Thus, FAIR- based CBF measurements show satisfactory reproducibility from day to day, but with sufficient variation to warrant caution in interpreting longitudinal data. The hemispheric asymmetry of baseline CBF and post-acetazolamide CBF increases varied within a narrower range and should be sensitive to small changes related to disease or treatment.  相似文献   
102.
BACKGROUND: Metastatic renal cell carcinoma (RCC) is an aggressive entity that frequently invades the venous system. We evaluated the morbidity and survival of patients with tumor thrombus who undergo cytoreductive nephrectomy. MATERIALS AND METHODS: We identified 56 patients from our institution's database who had a primary renal tumor in place and documented metastases at the time of surgery. We reviewed demographic and pathologic characteristics from these patients as well as complications and overall survival. RESULTS: Median age was 58 (37-77). There were 33 patients (59%) who had tumor thrombus with 21 (64%) involving the renal vein, 10 (30%) involving the infradiaphragmatic inferior vena cava (IVC), and 2 (6%) involving the supradiaphragmatic IVC. Median tumor size for thrombus patients was 12 cm (5-29). There were 8 (14.2%) who had complications, including 1 death. Thrombus patients were significantly more likely to have a complication (P = 0.008). Median survival for all patients was 10.7 months (0.3-61). There was no significant difference in overall survival between patients with and without thrombus (P = 0.76). CONCLUSIONS: Patients who undergo cytoreductive nephrectomy with a tumor thrombus have a higher rate of complications as compared to patients undergoing cytoreductive nephrectomy without tumor thrombus. The long-term survival, however, was not statistically different and thus aggressive surgery for select metastatic RCC patients is warranted.  相似文献   
103.
104.
This study involved an evaluation of two versions of the "premature aging" theory of chronic alcoholism: the accelerated aging and increased vumerabHty versions. The major dependent measures used were the tests included in Reitan's brain age quotient (BAO), a series of neuropsychological tests known to be sensitive to the effects of alcoholism and aging. Subjects were 40 chronic alcoholic inpatients and 40 matched controls, divided into age groups by; decade, ranging from the 30s to the 60s. It was proposed that an j interaction between age and presence or absence of alcoholism, with BAO test differences between alcoholics and controls widening as age increases, would support the increased vulnerability version, while the absence of such aw interaction would support the accel-] erated aging version. The results dearty favored the accelerated aging version, with merited BAO test differences between alcoholics, and controls appearing even in the 30-year-old groups. It was concluded that chronic ateohoftcs tend to perform at levels found for nonalconoiics 10 years their senior, but the discrepancy between, alcoholics and nonalcohoics does not increase with age.  相似文献   
105.
106.
Background: The efficacy of telerehabilitation-based treatment for anomia has been demonstrated in post-stroke aphasia, but the efficacy of this method of anomia treatment delivery has not been established within the context of degenerative illness.

Aims: The current study evaluated the feasibility and efficacy of a telerehabilitation-based approach to anomia treatment within the three subtypes of primary progressive aphasia (PPA).

Methods & Procedures: Each of the three telerehabilitation participants represented a distinct subtype of PPA. Following a baseline evaluation of language and cognition, a phonological treatment and an orthographic treatment were administered to all participants over the course of 6 months. One month after the end of treatment, a post-treatment evaluation began. All treatment sessions and the majority of the evaluation sessions were administered via telerehabilitation. Treatment effects were examined within each subject, and treatment effects were also compared between each telerehabilitation participant and a group of in-person participants who had the same subtype of PPA.

Outcomes & Results: All three telerehabilitation participants exhibited positive treatment effects. CGR (nonfluent/agrammatic variant PPA) and WCH (logopenic variant PPA) showed maintenance of naming for prophylaxis items under both treatment conditions, while ACR (semantic variant PPA) demonstrated increased naming of remediation items under the phonological treatment condition. Compared to in-person participants with the same subtype of PPA, each of the telerehabilitation participants typically showed effects that were either within the expected range or larger than expected.

Conclusions: Telerehabilitation-based anomia treatment is feasible and effective in all three subtypes of PPA.  相似文献   

107.

Background

Concern exists over the quality, accuracy, and accessibility of online information about health care conditions. The goal of this study is to evaluate the quality, accuracy, and readability of information available on the internet about lateral epicondylitis.

Methods

We used three different search terms (“tennis elbow,” “lateral epicondylitis,” and “elbow pain”) in three search engines (Google, Bing, and Yahoo) to generate a list of 75 unique websites. Three orthopedic surgeons reviewed the content of each website and assessed the quality and accuracy of information. We assessed each website’s readability using the Flesch–Kincaid method. Statistical comparisons were made using ANOVA with post hoc pairwise comparisons.

Results

The mean reading grade level was 11.1. None of the sites were under the recommended sixth grade reading level for the general public. Higher quality information was found when using the terms “tennis elbow” and “lateral epicondylitis” compared to “elbow pain” (p < 0.001). Specialty society websites had higher quality than all other websites (p < 0.001). The information was more accurate if the website was authored by a health care provider when compared to non-health care providers (p = 0.003). Websites seeking commercial gain and those found after the first five search results had lower quality information.

Conclusions

Reliable information about lateral epicondylitis is available online, especially from specialty societies. However, the quality and accuracy of information vary significantly with the search term, website author, and order of search results. This leaves less educated patients at a disadvantage, particularly because the information we encountered is above the reading level recommended for the general public.  相似文献   
108.
Neurofibromatosis type 1 (NF1) is a common genetic condition caused by mutations in the NF1 gene. Patients often suffer from tissue‐specific lesions associated with local double‐inactivation of NF1. In this study, we generated a novel fracture model to investigate the mechanism underlying congenital pseudarthrosis of the tibia (CPT) associated with NF1. We used a Cre‐expressing adenovirus (AdCre) to inactivate Nf1 in vitro in cultured osteoprogenitors and osteoblasts, and in vivo in the fracture callus of Nf1flox/flox and Nf1flox/? mice. The effects of the presence of Nf1null cells were extensively examined. Cultured Nf1null‐committed osteoprogenitors from neonatal calvaria failed to differentiate and express mature osteoblastic markers, even with recombinant bone morphogenetic protein‐2 (rhBMP‐2) treatment. Similarly, Nf1null‐inducible osteoprogenitors obtained from Nf1 mouse muscle were also unresponsive to rhBMP‐2. In both closed and open fracture models in Nf1flox/flox and Nf1flox/? mice, local AdCre injection significantly impaired bone healing, with fracture union being <50% that of wild type controls. No significant difference was seen between Nf1flox/flox and Nf1flox/? mice. Histological analyses showed invasion of the Nf1null fractures by fibrous and highly proliferative tissue. Mean amounts of fibrous tissue were increased upward of 10‐fold in Nf1null fractures and bromodeoxyuridine (BrdU) staining in closed fractures showed increased numbers of proliferating cells. In Nf1null fractures, tartrate‐resistant acid phosphatase–positive (TRAP+) cells were frequently observed within the fibrous tissue, not lining a bone surface. In summary, we report that local Nf1 deletion in a fracture callus is sufficient to impair bony union and recapitulate histological features of clinical CPT. Cell culture findings support the concept that Nf1 double inactivation impairs early osteoblastic differentiation. This model provides valuable insight into the pathobiology of the disease, and will be helpful for trialing therapeutic compounds. © 2012 American Society for Bone and Mineral Research  相似文献   
109.
Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Active surveillance of small renal masses has traditionally been reserved for elderly patients deemed unfit for surgery or ablation. There is increasing evidence showing the safety of active surveillance in the management of small renal masses. In this retrospective study we compared outcomes for patients with small renal masses managed with active surveillance, radical nephrectomy and partial nephrectomy. We showed that active surveillance was safe and appeared as effective as immediate surgery in the management of small renal tumours.

OBJECTIVE

  • ? To compare the oncological outcomes of active surveillance (AS), radical nephrectomy (RN) and partial nephrectomy (PN) in the management of T1a small renal masses (SRMs).

PATIENTS AND METHODS

  • ? At present AS is used in the treatment of SRMs in elderly patients with multiple co‐morbidities or in those who decline surgery.
  • ? We identified all patients with T1a SRMs managed with RN, PN or AS.
  • ? Retrospective data were collected from patient case records with survival data and cause of death cross‐referenced with the Oxford Cancer Intelligence Unit.

RESULTS

  • ? A total of 202 patients with 234 T1a SRMs (solid or Bosniak IV) were identified; 71 patients were managed with AS, 41 with an RN and 90 by PN.
  • ? Over a median follow‐up of 34 months the mean growth rate on AS was 0.21 cm/year with 53% of SRMs managed with AS showing negative or zero growth.
  • ? No statistically significant difference was observed in overall (OS) and cancer‐specific (CSS) survival for AS, RN and PN (AS‐CSS 98.6%, AS‐OS 83%; RN‐CSS 92.6%, RN‐OS 80.4%; PN‐CSS 96.6%, PN‐OS 90.0%).

CONCLUSIONS

  • ? Active surveillance of SRMs offers oncological efficacy equivalent to surgery in the short/intermediate term.
  • ? The results of this study support a multicentre prospective randomized controlled trial designed to compare the oncological efficacy of AS and surgery.
  相似文献   
110.
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