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71.
RATIONALE: The aim of the present study was to assess, intraindividually, the relationship among slow eye movements, electroencephalogram (EEG) power, and subjective measures of sleepiness during a 40-hour sleep deprivation comparing 2 experimental conditions: eyes-open and eyes-closed. METHODS: Nineteen normal subjects participated in a sleep-deprivation protocol with recordings of the waking Cz-A1-2 EEG in 36 sessions at 1-hour intervals starting at 10:00 AM. Each session consisted of a 2-minute eyes-closed period, followed by a 4-minute eyes-open period. Electrooculogram, self-ratings (Karolinska Sleepiness Scale and Visual Analog Scale for Global Vigor), and tympanic temperature were also recorded. RESULTS: Changes in sleepiness and alertness are paralleled by increases in slow eye movements and theta and delta EEG power. The beginning of the rise of delta, theta, and slow eye movement activity corresponded to the nadir of temperature, peaking at 7:00AM. Cross-correlational analyses showed that changes in slow eye movements were strictly phase locked to those in slow-frequency EEG bands and in subjective measures. The comparison of time intervals that were equivalent with respect to circadian phase confirms the effects of the increased sleepiness on slow eye movement activity and on the other measures. The temporal concordance of the different physiologic and subjective measures is also reflected in the individual time courses. Individual and group analyses converged in indicating that slow eye movements can be considered reliable indexes of sleepiness but only in the eyes-closed condition. CONCLUSIONS: Results suggest that subjective and EEG changes associated with higher sleepiness are paralleled by an increase in slow eye movement activity, but this relationship exists almost exclusively with the eyes closed. Hence, its use in practical and operational contexts seems limited.  相似文献   
72.
73.
ESR response to gamma-irradiation (1-50 Gy) of blends containing alanine and either B(OH)(3) or Gd(2)O(3) is reported. The sensitivity of the alanine--B(OH)(3) blend is comparable to the sensitivity of pure alanine, although its lowest detectable dose, LDD, is smaller ( approximately 1.3 Gy) than that of pure alanine ( approximately 2.9 Gy). Alanine with Gd(2)O(3) is about two times more sensitive than pure alanine, and its LDD is 0.8 Gy. The better sensitivity and LDD are probably due to the high atomic number (Z=64) of gadolinium, which enhances the interaction probability with photons and, consequently, the radical yield. This study suggests that other high-Z atoms may be useful for increasing the sensitivity of the response of alanine to gamma-radiation.  相似文献   
74.
Traumatic injury to peripheral nerves is a significant cause of morbidity and disability. Until reinnervation occurs, electrodiagnostic studies cannot differentiate severe axonotmetic lesions (Sunderland class 4) from complete nerve transection or neurotmesis (Sunderland class 5). This limitation is relevant clinically because in cases of neurotmesis an improved outcome may be achieved with an early surgical repair (within 1 week after trauma). High-resolution ultrasound (US) is an efficient modality to visualize injured nerves and is becoming increasingly important among radiologists and surgeons. Magnetic resonance (MR) imaging is complementary to high-resolution US, especially in evaluating deep-seated and proximal nerve segments. This article describes the imaging features of traumatic peripheral nerve lesions. The role of diagnostic imaging in stretching injuries, contusion trauma, penetrating wounds, and after surgery is discussed. A multimodality diagnostic approach including physical examination, electrophysiology, and US and MR imaging allows an accurate evaluation of most peripheral nerves. Imaging assessment of peripheral nerves trauma is useful for the diagnosis, follow-up, and postoperative evaluation.  相似文献   
75.

Introductions

Different staging systems have been devised for patients undergoing resection for hepatocellular carcinoma (HCC) with disparate results. The aim of this study was to create a new nomogram to predict individual survival after hepatectomy for HCC.

Methods

Based on the “Hepatocellular Carcinoma: Eastern & Western Experiences Network,” data from 2046 patients who underwent HCC resections at ten centers were reviewed. Patient survival was analyzed with Cox-regression analysis to construct a unique nomogram and contour plots to predict survival.

Results

The nomograms built on the multivariate analyses, which showed that the independent predictors were tumor size, tumor number, vascular invasion, cirrhosis, preoperative bilirubin value, and esophageal varices, showed good calibration and discriminatory abilities with C-index value of 0.62 (95 % CI, 0.59–0.69) and 0.61 (95 % CI, 0.56–0.64) for overall and disease-free survival, respectively. The 5-year survival contour plots showed that the presence of vascular invasion was associated with decreased survival, regardless of the tumor number or size. Cirrhosis and varices were equally associated with decreased survival, according to the tumor number or size.

Conclusions

These nomograms accurately predict individual prognosis after HCC resection and support an expansion of the selection criteria for resection. They offer useful guidance to clinicians for individual survival prediction.
  相似文献   
76.
OBJECTIVE: Treatment of varicocele using a microsurgical vein ligation approach is a successful procedure when applied to adult patients. We performed this procedure in prepubertal and pubertal patients in order to verify its feasibility and effectiveness in a younger population. MATERIAL AND METHODS: Between January 1998 and December 1999, 46 patients (average age 13 years) were operated on for a left varicocele using a microsurgical selective vein ligation procedure. All patients were evaluated clinically and using color Doppler ultrasound (CDUS): 34/46 patients were classified clinically as grade III and the remaining 12 as grade II. We used a magnification loupe (x3) in 34/46 patients and an operating microscope (x 10-16) in the remaining 12. RESULTS: The procedure was successful in all but one patient (2.1%) who showed recurrence of the disease at the time of the first postoperative follow-up CDUS scan and required a repeat procedure. The average operative times were 45 and 60 min for loupe and microscopic procedures, respectively. In three cases (6.5%), early postoperative complications (wound infection and transient hydrocele) occurred and quickly resolved. All the patients were discharged within 24 h, returned to normal daily life within 2 days and resumed physical and sporting activities within 1 week. CONCLUSION: Subinguinal "artery- and lymphatic-sparing" microsurgical varicocelectomy, considered the gold standard treatment in adults, also proved to be successful in this preliminary experience with pediatric patients. The minimally invasive approach ensures the prevention of recurrences and/or postoperative complications, and is associated with a very low morbidity rate.  相似文献   
77.

OBJECTIVE

To evaluate and define the risk factors predictive of chronic renal failure (CRF) in children with severe bilateral primary vesico‐ureteric reflux (VUR), observed within the first year of life and with a long follow‐up.

PATIENTS AND METHODS

The study comprised 50 patients presenting with grade 3–5 bilateral VUR diagnosed in the first year of life; 12 were suspected prenatally and confirmed shortly after birth, before any urinary tract infection (UTI). The mean (range) follow‐up was 6.3 (1–16) years. The variables considered within the first year of life were: gender, prenatal diagnosis with no UTI, number of febrile UTIs, serum creatinine and urea nitrogen levels, metabolic acidosis, proteinuria, 24‐h urine output, hypertension, bilateral renal length on ultrasonography and renal scarring on renal scintigraphy. CRF was defined as a creatinine clearance of <80 mL/min/1.73 m2 at the last follow‐up. The results were assessed using univariate and multivariate analyses (backward‐stepwise multiple regression) of the selected variables.

RESULTS

CRF was detected at the last follow‐up in 27 patients (54%), all boys, while renal function was normal in 23 (46%; seven girls). None of the 12 patients with prenatal diagnosis had UTI, but six had CRF. Febrile UTI was the presenting symptom in 38 (76%) patients and 17 (34%) of them had renal scarring. There was no significant difference between the prenatally detected VUR and febrile UTI group in the outcome as CRF. The univariate and multiple regression analysis showed that the first serum creatinine threshold of >6 mg/L before 1 year old was the most significant risk factor for CRF (P < 0.001; odds ratio 1.25).

CONCLUSIONS

Children with primary bilateral high‐grade VUR and a serum creatinine of > 6 mg/L in the first year of life have a significant risk of developing CRF in the long‐term. Prenatal diagnosis and postnatal febrile UTI do not modify the outcome for renal function.
  相似文献   
78.
We report a case of extensive acute thrombosis of portal vein and cava in a portocaval hemitransposition liver graft that was treated successfully with percutaneous pulse spray thrombolysis through a femoral vein access. The patient subsequently developed descending and sigmoid colon ischemic necrosis because of the venous thrombosis necessitating emergency colon resection. The patient had prolonged postoperative intensive care stay, but was eventually discharged in a good condition with normal liver function. Three month follow up demonstrated persistent normalization of hepatic function and normal duplex ultrasound.  相似文献   
79.
In order to assess the prevalence of Dopaminergic Premonitory Symptoms (DPS) in migraine patients with Restless Legs Syndrome (RLS), we chose migraine patients from a large Italian clinical headache population previously investigated for an association between primary headaches and RLS. We evaluated a total sample of 164 patients with migraine, in particular 114 with migraine without aura (MO), 10 with migraine with aura (MA) and 40 with MO and MA in various combinations between them or with episodic tension-type headache (ETTH), defined as a “mixed group”. About 20% of all migraine patients referred at least one of the following DPS: yawning, nausea, somnolence or food craving, confirming data already indicated in the literature. Among migraine patients with RLS (25.6%), DPS were referred from about half of the patients (47.6%) compared to those without RLS (47.6% vs. 13.1%; p<0.001). Based on migraine subtype, patients with MO referred DPS (26.3%) more frequently compared to the MA group and “mixed group” (12.0%, p<0.05), particularly in the presence of RLS (63.0% vs. 20.0%, p<0.01). No statistical differences were found between clinical and demographic data of the subgroups or related to medical conditions investigated (anxiety, depression, sleep disorders, body mass index). It is interesting that the chances of having RLS in migraine patients were more than 5 times higher in the presence of DPS. These results could support a hypothetical dopaminergic imbalance in RLS and migraine, as the dopamine is involved in the pathogenesis of both disorders and it is responsible for the migraine DPS reported above.  相似文献   
80.
Autoantibodies in juvenile dermatomyositis   总被引:2,自引:0,他引:2  
Fourteen patients with juvenile dermatomyositis (JDM) have been investigated for the presence of several serum autoantibodies: antinuclear (ANA), anti-single-stranded and double-stranded DNA, anti-histones, anti-Sm, anti-ribonucleoprotein, anti-SSA/SSB, anti-PM-1, anti-Jo-1, anti-mitochondrial, anti-smooth muscle, anti-gastric parietal cells, anti-cardiolipin (ACA) antibodies and rheumatoid factor. Patients were negative for all autoantibodies except for ANA and ACA. ANA were detected in 50% of the patients when tested on rat liver, but the percentage of positivity rose to 86% when HEp-2 cells were used as substrate. This finding suggests that HEp-2 cells represent a more sensitive substrate than rat liver for the detection of ANA in JDM. Three patients were positive for ACA; two of these presented vascular complications, thus suggesting a possible relationship between ACA and vascular involvement in JDM.  相似文献   
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