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91.
Neuroblastoma, the most common form of childhood cancer, may arise from a biochemical block of cellular differentiation and a resultant continuation of a proliferative state. Neuroblastoma often spontaneously reverts by undergoing partial differentiation and ultimate degeneration and may be associated with the generation of reactive oxygen species (ROS). We have recently reported in neuroblastoma cell culture studies that an anti-oxidant synergy formulation (ASF) can induce differentiation and buffer neuronal degeneration and oxidative stress in cultured cortical neurons and in central nervous system tissue of apolipoprotein E-deficient mice. The objective of the present study was to investigate whether a subcutaneous injection and/or transdermal application of a nanoemulsion preparation of ASF would reduce tumor growth rate in a neuroblastoma xenograph mouse model. The results indicate that whereas suspensions of ASF were ineffective in decreasing tumor growth rate in the neuroblastoma mouse model, tumor growth rate was similarly reduced an average 65% by either subcutaneous injection or transdermal application of an ASF nanoemulsion preparation to the tumor. In conclusion, the data suggest that subcutaneous and/or transdermal application of an ASF nanoemulsion preparation is effective in reducing tumor growth rate in this neuroblastoma mouse model.  相似文献   
92.
Twenty-seven 2- to 4-yr-old cebus monkeys (Cebus albifrons) were fed from infancy purified diets containing lactalbumin, soy isolate, casein or soy concentrate as the sole protein source. Hematologic and clinical chemistry values were similar for all groups. Head and tail portions of each pancreas were surgically removed for histopathologic evaluation and determination of protein, RNA and DNA content, and for trypsin and chymotrypsin activity. Hematoxylin and eosin-stained sections from 26 of 27 monkeys showed normal pancreatic tissue with occasional acinar vacuolation in all diet groups. The remaining animal, one of only two fed soy concentrate, had diffuse interstitial fibrosis of the pancreas associated with mild to moderate atrophy of acinar tissue. Biochemical analyses of the pancreatic biopsies indicated no group differences among animals fed lactalbumin, soy isolate or casein. One of two monkeys in the soy concentrate group showed decreased pancreatic protein, RNA and trypsin concentrations; this was probably due to the fibrosis in this animal. No evidence of pancreatic hypertrophy or hyperplasia, as measured by RNA/DNA and protein/DNA ratios, respectively, was seen in any diet group.  相似文献   
93.
OBJECTIVE: To monitor and describe the time trends of the HIV epidemic among intravenous drug users (IDU) attending drug dependence treatment centres (DDTC) in Northern Italy. DESIGN: A cohort of all seronegative IDU attending DDTC in Lombardy between 1993 and 1999; all had been tested for HIV at least twice. Periodic sample interview surveys were done to assess risk behaviours. METHODS: The incidence rates of HIV infection were calculated using the person-year (PY) method and expressed as the number of cases per 1000 PY at risk. Background HIV prevalence was calculated by dividing the number of positive cases by the total number of IDU tested at all DDTC in Lombardy. RESULTS: Between 1993 and 1999, 135 seroconversions occurred in 7945 subjects followed for 19 671 PY, yielding an incidence rate of 6.9/1000 PY. Ninety seroconversions occurred among the 6563 males and 45 seroconversions among 1382 females (incidence rates 5.5 and 14.0, respectively). Among the males, the incidence of HIV was 4.5 in those aged less than 25 years and 5.8 in those aged 25 years or more. Among the females, the corresponding figures were 21.1 and 10.3. HIV prevalence decreased over time, and it was higher among females. Sexual behaviours at risk were more common among females. CONCLUSIONS: The incidence of HIV infection among IDU in Northern Italy was stable between 1993 and 1999. The higher incidence and prevalence among females and the different prevalence of risk behaviours between genders suggest an increasing role of heterosexual transmission.  相似文献   
94.
Focal hand dystonia in a patient with thoracic outlet syndrome   总被引:1,自引:0,他引:1       下载免费PDF全文
A patient affected by thoracic outlet syndrome, with aninvolvement of the left lower primary trunk due to a rudimentarycervical rib, developed a severe hand dystonia on the same side. Thedystonic posture was characterised by a flexion of the wrist with thefingers curled into the palm. Polygraphic recordings performed on the left flexor digitorum superficialis (FDS4) and extensor digitorum superficialis (EDC4) muscles, during a repetitive tapping task of thefourth digit, showed a loss of well formed bursts without a clearsilent period along with long duration bursts of cocontraction inantagonistic muscles. The study of reciprocal inhibition between forearm flexor and extensor muscles showed a reduced amount of inhibition in both the disynaptic and the later presynaptic phase ofinhibition. The patient underwent an operation with resection of thecervical rib. Twelve hours after the operation the patient experienceda significant improvement of the hand dystonia; the distonia haddisappeared completely by two months with a progressive normalisationof reciprocal inhibition.

  相似文献   
95.
We measured plasma corticotropin-releasing hormone (CRH), ACTH, beta-endorphin (beta-EP), and cortisol levels as possible tumor markers in a sequence of 103, randomly selected, patients with lung cancer but without the ectopic Cushing's syndrome and in 72 age- and sex-matched controls. Plasma CRH levels of cancer patients were similar to those of controls both in patients sampled in the morning or in the afternoon. On the other hand, plasma ACTH levels of cancer patients were significantly higher than control patients both in the morning and in the afternoon and showed a preserved circadian rhythm. However, about 35% of cancer patients sampled in the morning and about 60% of those sampled in the afternoon had ACTH levels within the 95% confidence interval (CI) of controls. Also plasma beta-EP levels were more elevated in cancer patients than controls in the morning but about 33% of them and about 80% of those sampled in the afternoon had beta-EP levels within the 95% CI of controls. Despite the higher plasma ACTH levels, cancer patients had cortisol plasma levels similar to controls with preserved circadian rhythm. In conclusion, although mean plasma ACTH and beta-EP were higher in patients affected by lung cancer, their measurements, as well as those of CRH, have practically no diagnostic value. Perhaps measurement of ACTH levels in the bronchial lavage may be more helpful.  相似文献   
96.
The familial occurrence of hypertrophic cardiomyopathy is well known; familial dilated cardiomyopathy has so far received less attention. Ten families with two or more members affected by dilated cardiomyopathy were studied by echocardiography. In 3 out of 10 families, a transverse study extended to even apparently healthy subjects was carried out, which included a total of 45 subjects. In 19 out of the 45, dilated cardiomyopathy (either symptomatic or asymptomatic) was diagnosed at echocardiography. Three more relatives, already dead of the disease, were identified through hospital records. A clinical and echocardiographic longitudinal study, lasting up to 11 years, was carried out in 5 of the 10 families. During the follow-up, 8 out of 19 patients who, at first examination were affected by dilated cardiomyopathy, died, one improved, 3 remained in stable condition and 7 were lost at follow-up. One of two patients who presented echocardiographic findings suggestive of border-line dilated cardiomyopathy returned to normality and the other developed dilated cardiomyopathy. The clinical and echocardiographic findings in our patients, and in their relatives, suggest the possibility that idiopathic dilated cardiomyopathy may be a multifactorial disease in which genetic factors might play a variable role.  相似文献   
97.
In the last 10 years 20 patients with Hürthle tumors were observed at Institute of Surgery and Oncology of Cagliari University. 17 were females and 3 males with a median age of 42 years. Tumors were malignant in 7 cases and benign in 13. A total thyroidectomy was performed in all patients with carcinoma and in 2 with adenoma because of concurrent goiter. The remaining patients were treated with a less extensive surgery. Two patients with carcinoma had a cervical node metastases at 12 and 67 months, treated by surgery (followed by radioiodine therapy in one). All patients are alive and disease free at 72 months of median follow-up. None of patients with benign adenomas recurred at 47 months of median follow-up. A longer-term follow-up is necessary in order to evaluate the benignity of adenomas.  相似文献   
98.
小鼠颅神经嵴细胞的培养和特征   总被引:6,自引:4,他引:2  
目的:在体外原代培养Balb/c小鼠胚胎的颅神经嵴细胞。为颅面部各种组织细胞的发育研究提供细胞来源。方法:采用胰酶消化法分离小鼠胚胎第8.5天的颅神经管,从小鼠颅神经管中游离出来的细胞即为颅神经嵴细胞,用免疫组织化学方法鉴定细胞的来源,并测定细胞的生长曲线。结果:成功地培养出小鼠的颅神经嵴细胞,其形态类似成纤维样细胞,免疫组化检测结果表明,神经特异性烯醇化酶(NSE)抗体染色结果阳性。细胞的群体倍增时间为43.65h。结论:原代培养的小鼠颅神经嵴细胞生长稳定,来源明确,是颅面部各种细胞的发育和分化研究中一种有用的工具。  相似文献   
99.
The incidence of brain abscess was studied on all cases occurring in residents of Olmsted County, Minn., from 1935 through 1981. Thirty-eight cases (9 cases first diagnosed at autopsy) were identified and followed through the Rochester Olmsted County medical record-linkage system at the Mayo Clinic. The incidence rate was 1.3/100,000 person-years (PY), 1.9 in males and 0.6 in females. Incidence decreased from 2.7 in 1935-44 to 0.9 in 1965-81. Rates were higher in children 5-9 years old (2.4) and after age 60 (2.6 PY). An etiologic agent was identified in 29 cases (76%) with streptococci being the most frequently isolated. Case-fatality ratio was 38% (11/29), stable over time. Concurrent bacterial meningitis was the strongest predictor of death. Neurologic sequelae were observed in 8 (44%) of the 18 surviving patients including epilepsy (5 cases), deafness and motor impairment.  相似文献   
100.
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