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181.
To evaluate the capabilities of ultra-low-field MR for the high-resolution imaging of the knee with a short acquisition time, a prospective double-blind study was carried out on 40 consecutive patients with acute or chronic articular conditions who were examined with both MR imaging and arthroscopy. Three-dimensional gradient-echo MR sequences were employed which allow many thin high-resolution slices to be obtained in a relatively short time. To evaluate the results arthroscopy, performed the day after MR imaging, was considered the gold standard. MR imaging and arthroscopy were in agreement in 84.6% of meniscal tears with 91.6% sensitivity and 80% specificity, in 82% of anterior cruciate ligament lesions with 100% sensitivity and 80% specificity and in 81% of cartilage lesions with 100% sensitivity and 61% specificity. On the whole, MR imaging and arthroscopy were in agreement in 82.5% of cases with 97.2% sensitivity and 75.3% specificity. MR imaging gave more information about collateral ligament, muscle and bone involvement. These results confirm the capabilities of ultra-low-field MR imaging in the study of the knee: the technique allows diagnostic studies to be performed in a short time, at a low cost, and with similar results to those obtained with higher field strengths. 相似文献
182.
The research was designed to investigate the moderating effect of some personality traits on subjective distress caused by daily hassles. The traits were internal locus of control, repression, ego strength, and barrier (as studied and defined by S. Fisher). The last two variables were negatively correlated both with the somatic and emotional distress indications and with the frequency of hassles reportED; internal locus of control showed an inverse relationship only with frequency of hassles. The hypothesis is formulated that ego strength and barrier are personality factors influencing not only the outcomes of coping (ie the stress response), but also event appraisal. 相似文献
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C-fos immunoreactivity was used to reveal brain areas in which neurons were influenced by electrical stimulations applied to the dorsal periaqueductal gray. These stimulations were applied in freely moving rats so that the resulting behaviors could be observed. Shortly afterwards, the brains of the rats were processed for C-fos immunoreactivity. In order to determine the specificity of the brain areas thus labeled, control stimulations were applied to the ventral tegmental area of other rats. Immunoreactive cells were found surrounding the tip of the stimulation electrode within a radius of 0.5 mm. This labeled area extended further along the rostro-caudal axis than along the medio-lateral or dorso-ventral axis in the periaqueductal gray. Distally, clusters of labeled cells were found ipsilaterally in the caudal periaqueductal gray extending to the nucleus cuneiformis, and bilaterally in the locus coeruleus and supramamillary decussation. More widespread labeling was found in most hypothalamic subareas and in the lateral habenula. The labeled brain areas following ventral tegmental area stimulations were totally distinct, and comprised the medial forebrain bundle, the nucleus accumbens, the vertical limb of the diagonal band and the medial septum. The pattern of labeling produced by periaqueductal gray stimulations was therefore specific, and provided information about brain structures involved in the motivational and behavioral effects of such stimulations. 相似文献
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186.
Hemimegalencephaly: clinical implications and surgical treatment 总被引:2,自引:0,他引:2
C. Di Rocco D. Battaglia D. Pietrini M. Piastra L. Massimi 《Child's nervous system》2006,22(8):852-866
Introduction Hemimegalencephaly (HME) is a quite rare malformation of the cortical development arising from an abnormal proliferation of anomalous neuronal and glial cells that generally leads to the hypertrophy of the whole affected cerebral hemisphere. The pathogenesis of such a complex malformation is still unknown even though several hypotheses are reported in literature.Background HME can occur alone or associated with neurocutaneous disorders, such as neurofibromatosis, epidermal nevus syndrome, Ito’s hypomelanosis, and Klippel–Trenonay–Weber syndrome. The clinical picture is usually dominated by a severe and drug-resistant epilepsy. Other common findings are represented by macrocrania, mean/severe mental retardation, unilateral motor deficit, and hemianopia. The EEG shows different abnormal patterns, mainly characterized by suppression burst and/or hemihypsarrhythmia. Although neuroimaging and histologic investigations often show typical findings (enlarged hemisphere, malformed ventricular system, alteration of the normal gyration), the differential diagnosis with other disorders of the neuronal and glial proliferation may be difficult to obtain. Hemispherectomy/hemispherotomy is the most effective treatment to control seizure, and it also seems to provide good results on the psychomotor development when performed early, as demonstrated by the literature review and by the reported personal series reported here (20 children). The surgical therapy of HME, however, is still burdened by a quite high complication rate and mortality risk. 相似文献
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188.
Anna Letícia Soares Marinez de Oliveira Sousa Luci Maria Dusse Ana Paula Salles Moura Fernandes Marcelo Carvalho Lasmar Bethania Alves Novelli Geralda de Fátima Guerra Lages Maria das Gra?as Carvalho 《Blood coagulation & fibrinolysis》2007,18(5):395-399
This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine. 相似文献
189.
Alvisa Palese Laura Regattin Francesca Venuti Anna Innocenti Carla Benaglio Laura Cunico Luisa Saiani 《Journal of wound, ostomy, and continence nursing》2007,34(6):649-654
PURPOSE: The purpose of the study was to evaluate the incidence of incontinence pad use among patients admitted to medical wards, the reasons why nurses decide to use an incontinence pad, the extent to which the use of pads is avoidable, and the outcome of inappropriate pad use after discharge from the hospital. METHODS: A prospective cohort study was conducted; patients admitted to medical wards were observed during hospitalization and a 7-day follow-up period after discharge. SUBJECTS AND SETTING: The study was conducted in 2 acute-care units in Northern Italy. All new patients admitted to the units were recruited. RESULTS: At the time of admission to the hospital, in addition to the 120 patients who already used incontinence pads, there was a 34% incidence of new cases (98/286). The most frequent reason why nurses decided to use this aid was incontinence caused by space-time disorientation, followed by limited mobility, incontinence, patient request, nursing shortage, and involuntary urine leakage not perceived by patient. Seventy patients out of 208 used incontinence pads unnecessarily for a total of 544 days. CONCLUSIONS: Decisions about the use of the incontinence pads are not always consistent with research-based or literature-based suggestions. Nurses should develop clinical guidelines or protocols for the appropriate use of incontinence pads. 相似文献
190.
G Belcaro M R Cesarone P Rohdewald A Ricci E Ippolito M Dugall M Griffin I Ruffini G Acerbi M G Vinciguerra P Bavera A Di Renzo B M Errichi F Cerritelli 《Clinical and applied thrombosis/hemostasis》2004,10(4):373-377
The aim of this study was to evaluate the occurrence of deep venous thrombosis (DVT) and superficial vein thrombosis (SVT) and its prophylaxis with an oral anti-edema and antithrombotic agent (Pycnogenol, Horphag, Research Management SA, Geneva, Switzerland) in long-haul flights, in subjects at moderate to high-risk of DVT and SVT. The study pre-included 244 pre-selected subjects; 211 were included (33 were excluded for several reasons due to logistic problems) and 198 completed the study; 13 subjects were lost for follow-up at the end of the flight, all for non-medical problems (i.e., for difficult connections). All subjects were scanned within 90 minutes before the flight and within 2 hours after disembarking. Subjects were supplemented with 100 mg Pycnogenol per capsule. Treatment subjects received two capsules between 2 and 3 hours before flights with 250 mL of water; two capsules were taken 6 hours later with 250 mL of water and one capsule the next day. The control group received comparable placebo at the same intervals. The flight duration was on average 8 hours and 15 minutes (SD 55 min) (range, 7.45-12.33). In the control group there were five thrombotic events (one DVT and four superficial thromboses) while only nonthrombotic, localized phlebitis was observed in the Pycnogenol group (5.15% vs. no events; p<0.025). The ITT (intention to treat) analysis detects 13 failures in the control group (eight lost to follow up + five thrombotic events) of 105 subjects (12.4%) vs. five failures (4.7%; all lost, no thrombotic events) in the treatment group (p<0.025). No unwanted effects were observed. In conclusion, this study indicates that Pycnogenol treatment was effective in decreasing the number of thrombotic events (DVT and SVT) in moderate-to-high risk subjects, during long-haul flights. 相似文献