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131.
OBJECTIVE: The changes in fatigue resistance of nickel-titanium rotary ProFile instruments after clinical use for shaping 10 curved molar root canals were evaluated in this study. STUDY DESIGN: Twenty-five sets of files #20, #25, and #30 and tapers .04 and .06 were divided into 2 groups, one with 10 sets of new files that were tested in a fatigue test bench device as a control. The other, experimental group, with 15 sets of clinically used files, was tested in the same device. The Student t test was employed to compare mean values of the measured parameters. RESULTS: A statistically significant decrease in the number of cycles to failure was determined for the clinically used files, as compared with the new ones. The fracture point was the same for all files tested. CONCLUSIONS: The clinical use of ProFile instruments for shaping curved canals reduces their fatigue resistance.  相似文献   
132.
133.
The immunohistochemical occurrence of the neurotrophin (NT) proteins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-4 (NT-4), and neurotrophin-3 (NT-3) is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. The NT-like immunoreactive structures were unevenly distributed and showed regional differences among cerebellar lobules and folia. NGF-, NT-4-, and NT-3-positive neuronal perikarya were observed in all specimens examined. At variance with the other neurotrophins, the BDNF antiserum labelled neuronal cell bodies only in newborn life and infancy, as well as extensive nerve fibre systems, whose density increased with age. The NT-antibodies, tested by Western blot on human cerebellum homogenates, revealed immunoreactive bands corresponding to proteins of heterogenous molecular weight. The results obtained provide a first demonstration of the tissue localization of the NTs in the human cerebellum from perinatal to adult age, thus suggesting their involvement in the development, differentiation and maintenance of the cerebellar connectivity. Codistribution of the four NTs or sets of them was observed in cortical and deep nuclei neurons. Multiple trophic roles for NTs, encompassing the classic target-derived and local mechanisms of support, are envisaged as significant in development, differentiation, and maintenance of the human cerebellar connectivity.  相似文献   
134.
In the present study, morphological examination of patients from two unrelated Polish families with CADASIL was performed. Using light microscopy, there were evident changes characteristic to the disease. On electron microscopy, deposits of granular osmiophillic material (GOM) were found not only in cerebral arteries and veins but also in cerebral capillaries and vessels of the internal organs. These findings indicate that pathological process in CADASIL is generalized and involves also small vessels devoid of smooth muscle cells. Therefore, we propose to consider a replacement for the name CADASIL that better reflects the morphological picture of the disease like, for example, cerebral autosomal dominant vasculopathy with subcortical infarcts and leukoencephalopathy (CADVaSIL) or, to preserve the commonly known acronym, cerebral autosomal dominant angiopathy with subcortical infarcts and leukoencephalopathy.  相似文献   
135.
Studied children with mild to moderate juvenile rheumatoid arthritiswho were massaged by their parents 15 minutes a day for 30 days(and a control group engaged in relaxation therapy). The children'sanxiety and stress hormone (cortisol) levels were immediatelydecreased by the massage, and over the 30-day period their paindecreased on self-reports, parent reports, and their physician'sassessment of pain (both the incidence and severity) and pain-limitingactivities  相似文献   
136.
Three keratoplasties were carried out on two patients because of nodular degeneration of the cornea. Progress after keratoplasty could be followed up in one eye for 17 months and in the other two eyes, for 2.5 and 9 years, respectively. The implant with the short follow-up of only 17 months remained glass-clear; nothing abnormal was discovered during the checkups. In the case of the other patient in whom a longer follow-up period was possible, the following findings were evident: (1) a remarkably late epithelial immune response in one eye (after 18 months) with subsequent incomplete reepithelisation and formation of fine, superficial, cloudy opacity (observation period 2.5 years); (2) formation of dense but flat, superficial areas of opacity in the cornea of the other eye (observation period 9 years). These areas may be regarded as a precursor of Salzmann’s corneal degeneration. No difference could be found between the histological findings in the explants and those in a degenerative pannus or an older scar caused by inflammation of the Bowman membrane.  相似文献   
137.
PURPOSE: To compare two protocols of epidural administration of racemic methadone for postoperative analgesia (continuous infusion and intermittent bolus), focussing on plasma concentration, analgesic efficacy and side effects. METHODS: Ninety patients undergoing abdominal or lower-limb surgery were randomly assigned to two groups in a prospective double-blind design. The continuous infusion patients (n=60) received initial doses of 3 to 6 mg followed by 6 to 12 mg by continuous infusion over 24 hr. The bolus administration patients (n=30) received repeated boluses of 3 to 6 mg of racemic methadone every eight hours. Pain intensity was assessed on a visual analog scale. Amount of supplementary analgesia was recorded, as was the incidence of side effects. Plasma methadone concentrations were determined by high performance liquid chromatography. Treatment was continued for 72 hr. RESULTS: Pain relief was good and comparable in both groups throughout the three days of treatment. No accumulation of plasma racemic methadone was observed in either group, although the concentrations were significantly higher in the bolus group. Miosis was significantly more frequent in the bolus group. CONCLUSION: Plasma methadone concentrations were significantly lower with continuous infusion. Plasma methadone accumulation, which is considered the main disadvantage for its purported influence on the incidence of side effects, did not occur at the doses used over the three days of treatment that we report.  相似文献   
138.
We assessed the prevalence of Parkinson's disease in Cantalejo, Spain. In 1994, we screened 1,579 persons (age > or = 40 years) using a high-sensitivity method. Cases fulfilling established clinical criteria were followed for a minimum of 3 years. Prevalences were compared with those from other door-to-door surveys. We detected 27 individuals with parkinsonism, 20 of whom had Parkinson's disease. The prevalence of Parkinson's disease increased with age and, when age-adjusted to European standards, was 9.01 per 1,000 (age 40 years and over; 10.78 in men and 5.23 in women). Of the 11 men, three were in Hoehn & Yahr grades III-IV, but six of the nine women were more severely affected. Overall, we found 18 newly diagnosed cases of parkinsonism, 13 of which were Parkinson's disease, and the majority of which were in men aged 80 years or older with a mean duration of illness of 5 years. Our prevalence figures are the highest reported, apparently because of the inclusion of several very elderly men. Parkinson's disease in Cantalejo is less severe in men than in women, particularly in those newly diagnosed. Despite the low numbers, the high prevalence and sex-related pattern are unexplained but they probably relate to the high sensitivity of the screening method.  相似文献   
139.
Registered nurses working at a teaching hospital in Kuwait were surveyed to assess the psychosocial variables associated with their intention to comply with glove-wearing recommendations. Perceived consequences and normative beliefs, as well as sex and years of nursing experience, significantly influenced their behavioral intentions, suggesting that improvements in intention to comply are more likely to come from practical demonstrations that show nurses the potential outcomes of both using and not using gloves.  相似文献   
140.
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