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991.
Ramified microglial cells were investigated in primary cultures of dissociated cerebral cortical tissue from rats. The identification of these cells was confirmed through immunohistochemical staining with 7 monoclonal antibodies selective for microglia. While there was significant variation in staining intensity with different antibodies, all stained the identified ramified cells; the antibodies OX-42 and ED1 yielded the most intense immunoreactivity. Based on distinctive morphological features, the microglia could be identified in living cultures where they were monitored using time-lapse video recording. This technique revealed extremely dynamic features of cellular plasticity and motility. Ramified microglia exhibited constant and rapid alterations in the size and shape of their cell body with an associated extension and retraction of processes; concomitantly, the cells moved about in a circumscribed area. These features of plasticity and motility were unique to this cell type, and correlated with OX-42 immunostaining. The microglia also possessed a differentially high level of pinocytotic activity; this too was correlated with OX-42 staining. From the nature of their morphological plasticity and motility, high pinocytosis, and cellular distribution, it is hypothesized that the ramified microglia specifically function as a system of fluid cleansing in normal brain tissue. 相似文献
992.
993.
Interethnic variation of drug metabolism 总被引:4,自引:0,他引:4
W Kalow 《Trends in pharmacological sciences》1991,12(3):102-107
There are many examples of differences between ethnically defined populations with regard to drug-metabolizing enzymes i.e. enzymes that serve as defences against exogenous chemicals. The prevalence of variants of enzymes such as monooxygenases, dehydrogenases, esterases and some transferases is not uniform, and this leads to differences in metabolism of drugs such as aspirin and diazepam, among others. Werner Kalow explains why the mere counting of a genetic variant may not be sufficient to uncover more major problems such as may be posed by multiple allelism or heterozygosity, and why it may be predicted that a large number of drugs will display interethnic differences in function. 相似文献
994.
Y Yoshimura M Oka T Sugihara K Mishima 《International journal of oral and maxillofacial surgery》1986,15(2):196-200
A case of a branchial cyst with a high amylase activity of the cyst fluid was found in a 58-year-old female. The literature on branchial cysts with high amylase activity is reviewed. Amylase that showed high activity in the cystic fluid was revealed to be due to the salivary isoenzymes (S3 and S4) which migrated more to the anodic side on electrophoresis. 相似文献
995.
We developed a homogeneous fluoroimmunoassay for detecting amphetamines in urine. Only fluorescence intensity need be measured because the emission of non-protein-bound fluorescein-labeled amphetamine is preferentially quenched by detergent micelles. In a previous reported prototype assay system for measuring gentamicin in serum we used fluorescein and dodecyl sulfate (Anal Chem 1985; 57:1928-30). We have found that favorable hydrophobic and (or) ionic character of the analyte and unfavorable polar and (or) ionic character of the fluor are important determinants of the desired interactions. An anionic detergent and fluorescein, therefore, should be appropriate for apolar of cationic analytes, such as gentamicin and amphetamines. A greater [H+] at the anionic micelle surface is important for quenching emission from the fluor moiety. Millimolar concentrations of dodecyl sulfate rapidly denature immunoglobulin unless hapten is bound with sufficiently high affinity. Affinity was sufficiently high for the antibody used in the prototype gentamicin assay but not for the amphetamine antibody. Thus for the amphetamine assay, we used a non-denaturing detergent, dodecyl(oxyethylene)12 sulfate. The assay requires 30 microL of specimen in 2 mL of total assay volume. Amphetamine(d-,dl-, and meth-), at a concentration of 1 mg per liter of urine, is readily detected. 相似文献
996.
W W Eaton A Romanoski J C Anthony G Nestadt 《The Journal of nervous and mental disease》1991,179(11):689-693
This analysis applies methods of screening to the problem of psychosis. A probability sample of 810 individuals from the Eastern Baltimore Mental Health Survey was interviewed in the self-report modality with the Diagnostic Interview Schedule and shortly thereafter by a psychiatrist. It is shown that a configuration of responses in the self-report modality can screen moderately well for psychosis, as measured by psychiatrists in the clinical modality. 相似文献
997.
C C Johnson T A Nicklas M L Arbeit D W Harsha D S Mott S M Hunter W Wattigney G S Berenson 《Southern medical journal》1991,84(11):1305-1312
The Heart Smart Family Health Promotion Program is a multidisciplinary, school-based program for cardiovascular risk reduction among high-risk children and their families. As a program that includes young adults at high risk, it is adaptable to a clinical practice. Nineteen fourth and fifth graders were selected as probands for elevated risk factors after a general screening to identify families for an intervention program. Twenty-three parents participated in a 12-week program focused on eating, exercise, and smoking behavior changes enhanced by behavicral support strategies. Weekly sessions were held in the auditorium/cafeteria of the elementary school and consisted of orientation and presentations, cardiovascular (CV) screening with medical feedback, activities, self-monitoring, counseling, and contingency contracting. Information gathered before and after the program included medical history, CV health knowledge and relevant behavior, blood pressure, serum lipid and lipoprotein values, anthropometric measurements, and urine electrolyte excretion. Both children and parents showed positive changes in eating habits and physical activity and significant changes in knowledge and blood pressure levels, while the children halted their weight gain. We believe this multidisciplinary, behavior-oriented, school-based program can be an effective cardiovascular risk intervention adaptable for a clinical office practice. 相似文献
998.
Complications following ureteroscopy 总被引:1,自引:0,他引:1
We report 4 cases of ureteral injury and stricture formation following ureteroscopic stone manipulation. Possible etiologies of stricture formation and our methods of managing them are discussed. The complications of ureteroscopy have been reported only rarely and the ureteroscopist should be aware that the procedure is not always benign. 相似文献
999.
Computed tomography (CT) was performed in 14 cases of tuberculous meningitis (TBM), 12 of which were examined during the acute phase of the disease. CT findings in these cases included internal hydrocephalus (6/12), internal combined with external hydrocephalus (2/12), focal lesions consistent with localized encephalitis (3/12), diffuse brain edema (1/12), and middle cerebral artery infarction (1/12). In comparison to 32 cases of nonspecific bacterial meningitis, internal hydrocephalus was found significantly more often in TBM than in nonspecific meningitis (p less than 0.01) making CT an additional tool for the differentiation of these conditions in doubtful cases. In addition, CT features of 2 cases of cerebral tuberculoma are presented. 相似文献
1000.