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101.
102.
介绍了一种新型的防腐杀菌剂--二羟甲基二甲海因的合成方法,采用5,-5二甲海因与甲醛在常压、碱性、冰浴下,反应2小时,产率88.6%。 相似文献
103.
Summary Using acetylcholinesterase histochemical and choline acetyltransferase immunocytochemical localization methods, this study has provided conclusive evidence for the existence of cholinergic neurons in the external cuneate nucleus of gerbils. By light microscopy, both acetylcholinesterase and choline acetyltransferase labelling was confined to the rostral portion of the external cuneate nucleus. Ultrastructurally, acetylcholinesterase reaction products were found in the nuclear envelope, cisternae of rough endoplasmic reticulum and Golgi saccules of some somata and large dendrites as well as in the membranes of small dendrites, myelinated axons and axon terminals. These neuronal elements were also stained for choline acetyltransferase; immunoreactivity was associated with nuclear pores, nuclear envelope, perikaryal membrane and all the membranous structures within the cytoplasm. Of the total choline acetyltransferase-labelled neuronal profiles analysed, 79% were myelinated axons, 15% dendrites, 4% somata and 2% axon terminals. The immunostained axon terminals consisted of two types containing either round (Rd type; 62.5%) or pleomorphic (Pd type; 37.5%) vesicles. Both were associated directly with choline acetyltransferase-positive dendrites. In contrast to the paucity of choline acetyltransferase-labelled axon terminals, numerous choline acetyltransferase-positive myelinated axons were present. It may thus be hypothesized that most, if not all, of the external cuneate nucleus cholinergic neurons are projection cells; such cells may give rise to axonal collaterals which synapse onto their own dendrites for possible feedback control. Choline acetyltransferase-positive dendrites were contacted by numerous unlabelled presynaptic boutons, 60% of which contained round or spherical synaptic vesicles (Rd boutons) and 40% flattened vesicles (Fd boutons), suggesting that these neurons are under strong inhibitory control. The preferential concentration of cholinergic components in the rostral external cuneate nucleus may be significant in the light of the highly organized somatotopy in the external cuneate nucleus and its extensive efferent projections to medullary autonomic-related nuclei. Our results suggest that the cholinergic neurons may be involved in somatoautonomic integration. 相似文献
104.
G. Pilkington S. Juneja L. Tan J. Matthews J. Quirk G. Lee P. Ironside I. Cooper D. Jose 《Hematological oncology》1993,11(4):195-205
The prognostic value of immunophenotyping lymphomas with a panel of monoclonal antibodies (Mab) to various lymphoid antigens was assessed by studying 47 cases of diffuse large cell lymphoma. Cell suspensions were analysed by flow cytometry after labelling by indirect immunofluorescence. Thirty-eight cases were demonstrated to be of B cell and nine of T cell phenotype. Univariate analysis demonstrated that survival was significantly longer in patients expressing higher levels of HLA-DR (p=0·01) and normal levels of CD8 (p=0·04) but was not significantly associated with any of the other antigens. Our results support the possible value of HLA-DR in determining the prognosis of patients with diffuse large cell lymphoma. 相似文献
105.
Michael Groeneweg Suzan Tan Annemieke M. Boot Johan C. de Jongste Jan Bouquet Maarten Sinaasappel 《Journal of cystic fibrosis》2002,1(4):583-280
BACKGROUND: Assessment of nutritional status in children with cystic fibrosis (CF) is clinically relevant. Methods to measure nutritional status should be reliable and non-invasive, and reference values should be available. AIM: To compare weight and height measurements and measurements of specific body compartments in children with CF. METHODS: In a cross-sectional survey of 58 children with CF (28 females), we compared height and weight (expressed as: weight-for-height, body mass index (BMI), height-for-age and weight-for-age) with fat mass (skinfold sum (SFS)), muscle mass (upper arm circumference (UAC)) and bioelectrical impedance analysis (BIA). Results were expressed as Z-scores, using Dutch reference values. RESULTS: BMI and weight-for-height were within the normal range (mean Z-score (range): -0.13 (-1.5, 2.7) and -0.02 (-1.7, 2.8)). Weight and height corrected for age were below normal (mean Z-score (range): -0.79 (-2.4, -0.05) and -1.2 (-2.8, 1.4) (P<0.01)). Lean body mass by skinfold sum (LBM(sfs)), UAC and BIA were also significantly below reference values (mean Z-score (range): -0.9 (-2.2, 1.8), -0.95 (-2.4, 1.8) and -1.1 (-3.6, 1.0) (P<0.01)). Lean body mass (LBM) by BIA correlated with LBM(sfs). BIA systematically underestimated LBM in both CF patients and in control subjects. CONCLUSION: Nutritional status of children with CF must be evaluated, using age-corrected weight and height expressed in Z-score. LBM estimated by SFS, UAC and by BIA appear to be useful, although longitudinal studies in CF children should be performed to evaluate their clinical significance in detecting changes in nutritional status. 相似文献
106.
The motor neuron disease (MND) refers to a group of progressive diseases with unknown reasons, which attacks the cells of the anterior horn of the spinal cord, the motor nuclei of the brain stem cranial nerves and the pyramidal cells of the cerebral motor cortex. It is characterized in clinic by atrophy of the muscles, myasthenia and even death due to paralysis of the respiratory muscle. Currently, there is still no any effective cure for this illness. 50-70% of the victims will die in 3 to 5 years, and the survival time for those with brain stem injuries is no more than two years.1 Since 1996, the authors have treated 31 cases of motor neuron disease with large dosage of qi-invigorating drugs in accordance with Prof. Liu Mocai's experience, and obtained certain therapeutic effects. A report follows. 相似文献
107.
Nonablative dermal remodeling with a 585-nm, 350-microsec, flashlamp pulsed dye laser: clinical and ultrastructural analysis. 总被引:1,自引:0,他引:1
David Goldberg M Tan M Dale Sarradet Marsha Gordon 《Dermatologic surgery》2003,29(2):161-3; discussion 163-4
BACKGROUND: A nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser is currently being used for the treatment of rhytides. OBJECTIVE: To analyze both clinical rhytid improvement and electron microscopic evidence of ultrastructural changes after treatment with a nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser. RESULTS: At 6 months after two treatments, 40% of the treated subjects noted mild improvement in rhytid appearance. Nontreating physician evaluation revealed some degree of improvement in 50% of the treated subjects. Mild improvement in quality and texture of the skin was also reported by 50% of the subjects. Electron microscopic evaluation showed ultrastructural changes that are consistent with new collagen formation. CONCLUSION: Treatment with a nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser can lead to both clinical and electron microscopic evidence of improvement in photo-damaged skin. 相似文献
108.
A double-blinded study was conducted to compare the effects of mupirocin and tetracycline ointments in the treatment of skin infections. 111 patients were available for clinical assessment, of which 53 were treated with mupirocin and 58 treated with tetracycline. Clinically, both groups were improved, and there was no significant difference. Bacteriological assessment however revealed a better response to mupirocin. Staphylococcus aureus and Streptococcus pyogenes were the most common organisms isolated. 99% of Staphylococci were sensitive to mupirocin compared with 61% to tetracycline and 29% to penicillin G. 57% of Group A beta haemolytic Streptococci were resistant to tetracycline compared to 14% to mupirocin. Gram-negative organisms were mostly resistant to both preparations. No side effects were observed in both treatment groups. This study suggests that mupirocin is a safe and effective topical preparation for treating most of our common skin infections. 相似文献
109.
采用动脉血氧饱和度仪对52例新生儿肺炎患儿,在雾化吸入治疗过程中的动脉血氧饱和度(SaO2)进行了监测,对比了吸氧与否对SaO2改变的影响。结查表明:与基础值比较,雾化吸入时患儿的SaO2显著下降(P<0.01),而雾化吸入同时吸氧者SaO2无明显变化(P>0.05),但两者比较具有显著性差异(P<0.01)。结果提示雾化吸入可使新生儿肺炎患儿SaO2下降;同时吸氧,对防止SaO2的下降有一定作用。 相似文献
110.
Respiratory symptoms and lung function effects of domestic exposure to tobacco smoke and cooking by gas in non-smoking women in Singapore. 总被引:6,自引:0,他引:6 下载免费PDF全文
STUDY OBJECTIVES--To investigate the effects of passive exposure to tobacco smoke and gas cooking at home on respiratory symptoms and lung function of non-smoking women. SETTING--Evidence on the effects of passive smoking and exposure to nitrogen dioxide from gas cooking on the respiratory health of adults is limited and variable. Over 97% of women in Singapore do not smoke, and a principal source of indoor air pollution for housewives is passive smoking and gas cooking. DESIGN--This was a cross sectional (prevalence) study of a population based sample of 2868 adults aged 20 to 74 years in Singapore. A structured questionnaire administered by trained interviewers was used to collect data on passive smoking, gas cooking, respiratory symptoms, and other relevant variables. Passive smoking was defined as exposure to cigarette smoke from one or more members of the household who had ever smoked. Gas cooking was defined in terms of the weekly frequency of gas cooking, as well as the frequency with which the respondent's kitchen was filled with heavy cooking fumes (rarely, occasionally, often). Forced expiratory volume in one second (FEV1) was measured by using a portable Micro-spirometer. Multivariate analyses were used to estimate relative odds of association for respiratory symptoms and FEV1 effect, with adjustment for potential confounding variables. PARTICIPANTS--Of a total of 1438 women in the sample, 1282 women who had never smoked provided questionnaire data and 1008 women provided acceptable readings of FEV1 for analysis. MAIN RESULTS--Passive smoking was significantly associated with greater relative odds of usual or chronic cough and phlegm, wheezing, and breathlessness on exertion, as well as lower FEV1. Greater relative odds of respiratory symptoms were also associated with the weekly frequency of gas cooking, although these results were statistically insignificant. Chronic cough and phlegm and breathlessness on exertion, however, were significantly associated with the frequency with which the kitchen was filled with heavy cooking fumes. A lower FEV1 was found in women who cooked frequently (more than thrice a week). CONCLUSION--Domestic exposure to cigarette smoke and gas cooking is associated with increased risks of respiratory symptoms and impairment of lung function in non-smoking women in Singapore. 相似文献