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101.
Regional cerebral blood flow (rCBF) was studied by SPECT using 133Xe in 42 children, aged 2 days to 19 years, considered as neurologically normal. rCBF was measured on cortical regions and on the cerebellum and thalamus. Curves for reference values and standard deviation were defined for each region. At birth, cortical rCBFs were lower than those for adults; after birth they increased until 5 or 6 yr of age to values 50%-85% higher than those for adults and thereafter decreased, reaching adult levels between 15 and 19 yr. Neonatal values of rCBF on cerebellum and thalamus were slightly higher than adult level, but not significantly; after age 1, they followed the common pattern for cortical curves. When rCBFs were expressed in percent global CBF, they were lower at birth than adult levels in the cortex, then increased and reached a plateau corresponding to the adult value before the second year of age. The time needed to reach normal adult values differed for each cortical region. The shortest time was found on the primary cortex and the longest on the associative cortex. Cognitive development of the child seems to be related to changes in blood flow of the corresponding brain regions.  相似文献   
102.
The effect of 5-HT1A agonists was studied in the isolation-induced social behavioural deficit test. The drugs 8-OH-DPAT (0.125 mg/kg), buspirone (16 mg/kg) and ipsapirone (8 mg/kg) further increased the deficit. Unlike 8-OH-DPAT, the other two drugs may act non-specifically since they reduced spontaneous motor activity at 16 mg/kg, as measured in an activity meter. In addition, 8-OH-DPAT (0.25 mg/kg), buspirone (8 mg/kg) and ipsapirone (8 mg/kg) decreased exploratory activity in the open-field test. Since the smallest active doses were very close in the behavioural deficit and in the open-field tests, it is suggested that a common phenomenon, increased emotionality or reactivity, sustained both these reductions in activity. The increase in the behavioural deficit induced by 8-OH-DPAT, was likely to have resulted from stimulation of 5-HT1A receptors, since it was impaired by pretreatment with penbutolol, a beta-adrenergic-blocking drug, also known to bind to 5-HT1 receptors. Since it was previously shown that the behavioural deficit was reduced by agonists at 5-HT1B receptors, it is proposed that the behavioural inhibition, resulting from an isolation-induced increase in reactivity is bi-directionally modulated by serotonergic drugs, where 5-HT1A agonists increase and 5-HT1B agonists decrease this inhibition.  相似文献   
103.
In our institution, total body irradiation (TBI) is performed by means of a sweeping beam technique. Toxicity of the procedure was evaluated according to the only grading system designed for high dose chemoradiotherapy. One hundred patients undergoing TBI and conditioned with a standard cyclophosphamide regimen before BMT were evaluated. Regimen-related toxicity was graded according to the Seattle transplantation toxicity system, from 0 to IV (fatal toxicity), in eight organs on days 0, 7, 14, 28 and 100 for lungs. Eighteen patients did not develop any toxicity. Grades III, IV toxicities were uncommon (9%) and were not influenced by dose of TBI, GVHD prophylaxis, disease status and allogenicity although no grade IV toxicity was observed among autologous marrow recipients. However, grade II toxicity was more common in patients receiving allogeneic vs autologous grafts (p < 0.01) because of increased mucosal (p = 0.002) and liver (p = 0.12) toxicities. Renal toxicity was unevaluable. When cumulative toxicity was equal or higher than 4, day 100 survival was worse (p = 0.05). These data confirm the safety of our TBI procedure and the validity of the grading system except for renal toxicity. We suggest that a more aggressive conditioning regimen may be tolerated by patients receiving autologous grafts.  相似文献   
104.
Brain macrophages synthesize interleukin-1 and interleukin-1 mRNAs in vitro   总被引:10,自引:0,他引:10  
Amoeboid microglial cells (brain macrophages) were purified from early post-natal mouse brain cultures. The percentage of cells stained with an anti-Mac-1 antibody was greater than 95%. Stimulation of these brain macrophages by lipopolysaccharides induced the synthesis of interleukin-1 (IL-1), which, in part, remained associated with the cell surface and, in part, was released into the culture medium. In contrast, pure primary astrocyte cultures and cell lines of transformed or immortalised astrocytes did not synthesise significant amounts of IL-1, demonstrating that amoeboid microglia and not astrocytes synthesise IL-1 in vitro. These physiological data were confirmed by RNA hybridisation studies showing that, on LPS treatment, brain macrophages synthesise significant amounts of IL-1 alpha and IL-1 beta mRNAs.  相似文献   
105.
In this prospective study, we have investigated incidence of injuries of different severity, types of injury, and mechanisms of injury during ice hockey practice and games. One Swedish elite hockey team was closely observed during three seasons (1982 to 1985). There was a total number of 95 injuries and 29 facial lacerations. The majority of injuries were minor (73%) and only 8% were classified as major. Seventy-six percent of the injuries occurred during games and 24% during practice. The incidence of injury during practice was 1.4 per 1,000 player-practice hours and 78.4 per 1,000 player-game hours. In comparison with other sports, the incidence of injury during hockey practice is very low, while that during games is high. Eighty percent of the injuries were caused by trauma and 20% by overuse. The most common types of injury were contusions, strains, and sprains. Complete tear of the medial collateral ligament of the knee was the most common severe injury. Most injuries resulted from body contact, predominantly tackling (checking), and from puck or stick contact. A reduction of the number of minor and moderate injuries should be possible by stricter enforcement of the hockey rules, especially against stick violations, and more widespread use of visors.  相似文献   
106.
Described in Switzerland in the early '60, the major features of hereditary non-polyposis colon cancer syndrome (HNPCCS) were established 20 years ago by H. T. Lynch. HNPCCS accounts for at least 60% of the colon cancer etiology. Cancer family syndrome is defined by the presence of extracolonic primary tumors in addition to colon cancer. Both syndromes are transmitted by an autosomic dominant pattern. None of the known biomarkers are specific and/or sensitive enough to rely on their predictive values of patient's risks. A typical Swiss family was investigated on the basis of the cancer-prone family history. 21% of the family members observed over 5 generations presented one or more (30% of the cases) colo-rectal neoplasms at the age of 50. 55% of the tumors were right sided. Histologically, half of the tumors were mucinous. 30% of metachronous cancer appeared within 10 years. Polyps (1-3) and flat adenomas were associated to the lesion in 57%. Extra-colonic tumors appeared in 18% of family members and in half of the colon cancer patients. The sites of these tumors were the urinary tract, ovary, small bowel, breast and stomach. Two fibroblast strains of affected individuals were established. No increased tetraploidy was noted. Preliminary results suggest that this two strains are rather sensitive to ionising radiation. Often neglected, family history of colon cancer remains the major diagnostic and decision-making tool of a such syndrome. It will necessitate special treatment of affected subjects and early screening of the relatives.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
107.
Cystic meningiomas. Report of seven cases   总被引:1,自引:0,他引:1  
Seven patients with cystic meningioma are reported. The computerized tomography appearance of these meningiomas may mimic that of a glial or metastatic tumor with cystic or necrotic changes, and lead to an incorrect presumptive diagnosis. Radiological evaluation and recognition are important for the surgical removal of these potentially curable neoplasms.  相似文献   
108.
The course of respiratory exchange through arterial blood gas analysis after coronary bypass-grafting and valvular replacement has been investigated in a cohort of 62 patients. Arterial blood gases were measured at baseline (the day before surgery), and then 1, 2, 3 and 9 days after surgery; in a subset of 18 patients, randomly selected from the same population, pulmonary function tests were also performed at baseline and repeated on day 9. Arterial blood gases showed a remarkable prevalence of hypoxaemia (as defined as arterial PaO2 less than 60 mmHg): 31% on the first, 50% on the second, and 40% on the third post-operative day; anemia and desaturated mixed venous blood were also prominent findings during the first two days. Arterial PO2 resulted higher afterward, although its mean value then was significantly lower than baseline (81.5 +/- 8.8 vs 93.1 +/- 9 mmHg, p less than 0.005). Pulmonary function tests evidenced widespread restrictive changes, with alterated thoraco-pulmonary mechanics (loss of more than 40% of vital capacity and one second forced expiratory flow) and parenchimal lung damage (residual volume and CO diffusion capacity decrease). Some differences in PaO2 course between coronary patients and valvular patients have been releaved; the mean basal PaO2 value of valvular was significantly lower then the other one (86.7 +/- 10.8 vs 94.7 +/- 10.9, p less than 0.05).  相似文献   
109.
Hypercalcaemia and pancreatic ultrastructure in cats.   总被引:3,自引:0,他引:3  
OBJECTIVE--To study the effects of local and systemic infusions of calcium on the ultrastructure of the pancreas in cats. DESIGN--Controlled study. INTERVENTIONS--Three groups of four cats each had local infusions (into the splenic artery) of calcium gluconate 0.6 mmol/kg.hour or potassium chloride 1.1 mmol/kg.hour, or sodium chloride 0.9%, for three hours. Two groups of eight cats each had systemic infusions (into the jugular vein) of either calcium gluconate 0.6 mmol/kg.hour or sodium chloride 0.9%, for twelve hours. In the group that was given calcium, the infusion rate was reduced after three hours to 0.3 mmol/kg.hour to maintain the hypercalcaemic state for a further nine hours. RESULTS--Local infusion of calcium caused destruction of acinar cells with hydropic degeneration of nuclei, discharge of cell organelles into the interstitial spaces, and extravasation of red blood cells but no apparent damage to the capillaries. There were no ultrastructural changes of any importance in the groups that received potassium or sodium chloride. Systemic infusion of calcium resulted in a 1.8 fold increase in the ionised calcium concentration in the serum, progressive signs of overstimulation of the Golgi apparatus with hypertrophy, fusion of condensing vacuoles, and disruption of the acinar cell polarization. This was followed by clumping of nuclear chromatin and destruction of acinar cells. CONCLUSION--Acute pancreatitis in cats can result from stimulation and destruction of acinar cells by hypercalcaemia.  相似文献   
110.
Pleural mesotheliomas are rare, and their diagnosis and treatment not clear. The case observed in our Department leads us to an analysis of the literature. This showed that differential diagnosis with pulmonary carcinoma is very difficult, even in cases of parietal mesothelioma; however local treatment may be performed even in malignant mesothelioma.  相似文献   
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