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1.
2.
We examined 334 legs in 167 consecutive patients with advanced peripheral ischemic disease using color Doppler sonography and angiography. Angiography revealed 714 lesions (369 nonsignificant stenoses, 297 significant stenoses, and 48 occlusions) in the 334 legs examined. Overall, color Doppler sonography revealed diagnostic agreement with angiography in 668 of 714 lesions (93.5%), including 343 of 369 (92.9%) nonsignificant stenoses, 279 of 297 (93.9%) significant stenoses, and 46 of 48 (95.8%) occlusions. Overestimation occurred in 26 of 369 (7%) nonsignificant stenoses and 3 of 297 (1%) significant stenoses. Underestimation was observed in 15 of 297 (5%) significant stenoses and in 2 of 48 (4.2%) occlusions. Peak systolic velocity ratio correlated better (P < 0.01) than peak systolic velocity with diameter reduction percentage as assessed at angiography. Color Doppler sonography is an accurate noninvasive method for evaluating patients with peripheral ischemic disease.  相似文献   
3.
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%.  相似文献   
4.
Dermatoglyphics in von Recklinghausen neurofibromatosis   总被引:2,自引:0,他引:2  
We studied dermatoglyphic traits in 27 patients (12 males and 15 females) with neurofibromatosis type I (NF-1) to verify which characteristics may be considered typical of this disorder. The frequency of digital central pockets in the patients was significantly greater than in control individuals (P less than .005), but when we evaluated the sexes separately, the difference was significant only among females (P less than .002). The distribution of central pockets on the various fingers was significantly different in affected females, compared with normal controls, but only on fingers II (P less than .05), IV (P .002), and V (P less than .05). The quantitative finger tip pattern values and the total finger ridge count (TFRC) were always higher in the patients, as well as was the a-b ridge count. The latter was significantly increased only on the right hand in females (P less than .01). Among the patients, the atd angle values were increased on both hands of females and on the right hand in males, whereas both the ulnar index A'-d and the a-t' ridge counts were diminished. The frequency of high endings (5' or 5") of line A was increased in NF-1 patients on both hands. Like in previous investigations, our patients showed an increased number of secondary creases, limited to II degree according to Vormittag et al. [1986] (P less than .048). Our results only partially confirmed prior data. Therefore, we think that there is no typical dermatoglyphic pattern in NF-1 and that this parameter is not a diagnostic indicator in this disorder.  相似文献   
5.
Left ovaries of bursectomized chick embryos were examined on the 17th day of incubation in comparison to normal and sham-operated controls, by histological and histochemical observations. The results show that in bursectomized embryos the cortex appears irregulary developed, with a significant decrease in the mean thickness and in the percentage of the secondary sex cords in the total cortical area. Furthermore, the germinal epithelium appears thicker and the subcortical medulla and the tunica albuginea more compact. The greater activity of the enzyme 5–3-hydroxysteroid dehydrogenase ( 53HSD) found in ovaries of bursectomized embryos (histochemical method) could be related to an endocrine dismetabolism affecting the cortical development. On the basis of these results and those of other authors, some hypotheses are advanced. In particular, an action of the bursal factor on GTH receptors could be the factor responsible of the enhanced steroidogenic activity altering the hormonal environment.  相似文献   
6.
7.
The aim of this study is to assess the neurophysiological abnormalities of type A botulin toxin-infiltrated human muscle, and their evolution over time. Seried cMAP measurements, 3 and 20 Hz repetitive nerve stimulation, EMG, SFEMG over 3 months from toxin injection. Our findings consist in lack of decrement with 3 Hz repetitive nerve stimulation and facilitation with 20 Hz repetitive nerve stimulation; progressive increasing of jitter; early appearance of fibrillations; small and short motor unit action potential in the first 3 weeks, followed by increasing of MUAP amplitude and duration, with polyphasic morphology. Although claimed as highly specific and sensible, neuromuscular junction facilitation is an inconstant finding in human botulism. Therefore, lack of neuromuscular junction facilitation cannot exclude a diagnosis of botulism. Our findings are compatible with a process of acute denervation followed by distal reinnervation, favored by terminal nerve sprouting.  相似文献   
8.
After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47?±?7 years, 30?% female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5?±?15 years; LVEF 63.5?±?7?%). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3?±?11?%) with higher LV mass relative to age-matched healthy volunteers (114?±?27 vs. 85.8?±?18 g; p?<?0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39?±?0.06 vs. 0.28?±?0.03, p?<?0.0001; τic: 0.12?±?0.08 vs. 0.08?±?0.03, p?<?0.001). ECV was associated with LV mass (r?=?0.74, p?<?0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35?±?0.02 for 0R vs. 0.45?±?0, p?<?0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.  相似文献   
9.
10.

Objective

To determine whether a powered ankle-foot orthosis (AFO) that provides dorsiflexor and plantar flexor assistance at the ankle can improve walking endurance of persons with multiple sclerosis (MS).

Design

Short-term intervention.

Setting

University research laboratory.

Participants

Participants (N=16) with a neurologist-confirmed diagnosis of MS and daily use of a prescribed custom unilateral passive AFO.

Interventions

Three 6-minute walk tests (6MWTs), 1 per footwear condition: shoes (no AFO), prescribed passive AFO, and portable powered AFO (PPAFO). Assistive devices were worn on the impaired limb.

Main Outcome Measures

Distance walked and metabolic cost of transport were recorded during each 6MWT and compared between footwear conditions.

Results

Each participant completed all three 6MWTs within the experimental design. PPAFO use resulted in a shorter 6MWT distance than did a passive AFO or shoe use. No differences were observed in metabolic cost of transport between footwear conditions.

Conclusions

The current embodiment of this PPAFO did not improve endurance walking performance during the 6MWT in a sample of participants with gait impairment due to MS. Further research is required to determine whether expanded training or modified design of this powered orthosis can be effective in improving endurance walking performance in persons with gait impairment due to MS.  相似文献   
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