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1.
Computed tomography (CT) analysis of the effects of chemonucleolysis   总被引:1,自引:0,他引:1  
Computed tomography (CT) was performed on 30 patients with herniated lumbar discs before chemonucleolysis and at three and 12 months postinjection. At three months the compression produced by the herniated disc was reduced in 20 of the 30 patients; at 12 months there was complete relief of compression in all but four patients. Twenty-four patients developed diffuse bulging of the annulus. There was good correlation between the clinical results at three months and the reduction in compression as shown by the CT scan. At 12 months, no correlation was found between the remaining focal abnormalities and the clinical result. None of the patients developed epidural fibrosis. Chemonucleolysis has thus been shown to be an effective treatment of herniated lumbar discs, but it is definitely not indicated in cases where compression of the nerve root or dural sac is due to a bulging annulus.  相似文献   
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To determine if chronic haloperidol (3.0 mg/kg per day) or chlorpromazine (4.2 mg/kg per day) treatment alters central beta-endorphin metabolism, haloperidol and chlorpromazine were perfused via Alzet minipumps into male Sprague-Dawley rats for 8 days. Crude twice-washed membranes, purified synaptic plasma membranes and Golgi-enriched membranes, respectively, were isolated from rat brains and time course incubated with beta-endorphin. All samples were analyzed by high resolution, reversed-phase high performance liquid chromatography. The half-lives of beta-endorphin for animals treated with haloperidol or chlorpromazine were not statistically different from control animals at the crude washed membranes. At the purified synaptic plasma membranes, however, the half-lives of beta-endorphin from haloperidol (t 1/2 = 45.1 min)- and chlorpromazine (t1/2 = 47.0 min)-treated animals were significantly decreased as compared to the control animals (t1/2 = 78.0 min). The half-life of beta-endorphin at the Golgi-enriched membranes was increased for haloperidol (t1/2 = 112.3 min) and chlorpromazine (t1/2 = 103.0 min)-treated animals when compared to control animals (t1/2 = 80.2 min). The findings indicate a differential effect of the dopamine receptor antagonists haloperidol and chlorpromazine on the extracellular fate at the synaptic plasma membranes of beta-endorphin and the intracellular processing at the Golgi-enriched membranes in vitro.  相似文献   
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A method for estimation of arginine in 50 microliters serum was developed using commercially available arginine kinase (EC 2.7.3.3). The assay is based on the transformation of arginine and ATP into phospho-arginine and ADP by the enzyme. ADP is measured by two coupling reactions involving pyruvate kinase (EC 2.7.1.40) and lactate dehydrogenase (EC 1.1.1.27) with measurement of NADH consumption at 340 nm. The method involves preincubation of serum in the reaction medium without arginine kinase to eliminate side reactions and a kinetic rate protocol with measurements of absorbance at 60 s and 180 s. Reaction temperature is 30 degrees C. The reaction is linear up to at least 3 mmol/l of arginine. Within-batch CV is less than 3% for arginine levels above 0.75 mmol/l and the between-batch CV is 6.5% or less. The method correlates well with an automatic amino acid analyzer procedure (r = 0.983). The reference range derived from sera of 40 blood donors has been determined to be 0.06-0.20 mmol/l.  相似文献   
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To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice.  相似文献   
7.
OBJECTIVE: To document infection with HIV type 1 (HIV-1) group M non-B subtypes in individuals living in New York City. DESIGN: From October 1999 through April 2003, HIV-1-seropositive individuals were selected from 3 clinics in New York City based on having risk factors for infection with HIV-1 non-B subtypes. METHODS: HIV-1 RNA was extracted from plasma samples, and partial gag, pol, or env genes were amplified by PCR analysis. The infecting HIV-1 group M subtype was determined based on results of either heteroduplex mobility assay or sequencing and phylogenetic analysis. RESULTS: Ninety-seven subjects were enrolled in the study. Of the 97 subjects, 91 (94%) were selected based on having emigrated from a non-European country, while 6 (6%) were native United States citizens. Subtypes were successfully determined in 53 (55%) of the 97 plasma samples tested. The subtypes in 2 plasma samples were unclassifiable. HIV-1 infections were classified as those due to the following group M subtypes: A (n = 4; 7%), B (n = 12; 22%), C (n = 8; 15%), F (n = 2; 4%), CRF01_AE-like (n = 7; 13%), CRF02_AG-like (n = 19; 34%), an intersubtype recombinant form G/A (n = 1; 2%), and unclassifiable viruses (n = 2; 4%). CONCLUSION: This study reveals infection with a broad variety of HIV-1 group M subtypes mostly in the immigrant population of New York City as well as how several non-B subtypes are being introduced into the United States.  相似文献   
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The expression of the pfemp3 gene and the corresponding PfEMP3 knob-associated protein in the pre-erythrocytic stages of Plasmodium falciparum was demonstrated by RT-PCR, Western blots, IFAT and IEM. The antigen was found on the surface of the sporozoite and in the cytoplasm of mature hepatic stage parasites. Immunological cross-reactivity was observed with sporozoites from the rodent malaria parasites Plasmodium yoelii yoelii and Plasmodium berghei and was exploited to assess a potential role of this protein at the pre-erythrocytic stages. Specific antibodies from immune individuals were found to inhibit P. yoelii yoelii and P. berghei sporozoite invasion of primary hepatocyte cultures. PfEMP3 should now be added to the small list of proteins expressed at the pre-erythrocytic stages of P. falciparum, and its vaccine potential now deserves to be investigated.  相似文献   
10.
Conclusie De verscheidenheid aan conserveermiddelen die in cosmetica worden toegepast, is zeer groot. Het is wenselijk het gebruik van deze verbindingen zo beperkt mogelijk te houden in verband met ongewenste bijwerkingen voor de gebruikers. Een effectieve conservering van produkten, waarin micro-organismen goed kunnen groeien, is echter noodzakelijk. Deskundige microbiologische begeleiding bij de ontwikkeling en fabricage van cosmetische produkten is dan ook essentieel.

Voordracht gehouden tijdens het symposium Conserveermiddelen op 13 november 1980 te Rotterdam.

Dit artikel wordt gelijktijdig geplaatst in De Waren Chemicus.  相似文献   
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