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161.
162.
One hundred twelve peripheral blood specimens were tested for the presence of cytomegalovirus (CMV) by the tube culture indirect immunoperoxidase (TC-IPA) procedure, the shell vial assay [shell vials were pre- and postinoculation treated with medium containing 2 of 10% fetal bovine serum (FBS) or 100 micrograms% cortisol] (SV-IFA), and conventional (MRC-5) tube cultures (TC-CPE). CMV was detected in 25 (22%) of the 112 specimens tested by at least one of these methods. The detection/isolation of CMV among the 25 positive specimens in shell vials maintained with 2% FBS, 100 micrograms% cortisol + 2% FBS, and 10% FBS was 36, 44, and 52%, respectively. Detection/isolation of the virus from blood by TC-IPA and TC-CPE was 52% and 76%, respectively. A significantly greater CMV detection rate occurred using TC-CPE compared to SV-IFA treated with medium supplemented with an FBS concentration of 2% (P = .0132), but not medium containing the higher serum supplement or the glucocorticoid (P greater than .05). Differences in the identification of a CMV viremia were observed by IPA, SV-IFA, and TC-CPE methodologies on a patient-to-patient basis, denoting the necessity of incorporating each methodology into the CMV screening panel. Demographic analysis of 82 AIDS patients showed a CMV viremia prevalence of 9% (2/28) in intravenous drug users, 57% (27/47) in homosexual patients, and 22% (2/9) in heterosexual and transfusion patients. Overnight (24 hr) storage of whole blood at 4 or 24 degrees C, respectively, reduced CMV recovery by 40% and 65%, when tested by TC-CPE.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
163.
The purpose of this article is to document clinical and pathologic observations concerning liver disease associated with the PI ElembergM phenotype of alpha 1-antitrypsin. Deposits of alpha 1-antitrypsin that were periodic acid-Schiff positive and stained with an antiserum to alpha 1-antitrypsin were found in the liver of a markedly jaundiced, terminally ill patient with Stage IV primary biliary cirrhosis. A biopsy performed three years earlier failed to reveal alpha 1-antitrypsin deposits. The phenotype PI ElembergM was verified by both acid starch gel electrophoresis and isoelectric focusing in agarose. The deposits of alpha 1-antitrypsin in the liver appear to be a consequence of the patient's disease and age and not due to an association with the PI*Elemberg allele. Accumulation of alpha 1-antitrypsin in the liver of this patient may be due to an accelerated synthesis of this protease inhibitor exceeding the liver's capacity for glycosylation or other steps in its secretion. 相似文献
164.
D L Weinbaum S S Kaplan U Zdziarski C R Rinaldo Jr K K Schroeder 《Infection and immunity》1984,43(3):791-794
The effects of cyclosporin A (cyA) on human polymorphonuclear leukocyte function, including phagocytosis, its associated metabolic burst, bacterial killing, and chemotaxis, were evaluated. Both Pseudomonas aeruginosa and Staphylococcus aureus were used as test particles. Polymorphonuclear leukocytes incubated in 10 and 50 micrograms of cyA per ml behaved normally with respect to phagocytosis and hexose monophosphate shunt activity at both high (10:1) and low (2:1) S. aureus/leukocyte ratios. With a small bacterial inoculum, killing of S. aureus was slightly impaired at early times only in the presence of 50 micrograms of cyA per ml. Phagocytosis and killing of P. aeruginosa with both large and small bacterial inocula were unaffected by cyA. Chemotaxis was within normal limits under all conditions. In addition, polymorphonuclear leukocytes from four renal transplant recipients receiving both cyA and prednisone demonstrated normal metabolic bursts and bacterial killing with both small and large inocula of S. aureus. 相似文献
165.
Comparison of two rapid culture methods for detection of cytomegalovirus in clinical specimens. 总被引:1,自引:7,他引:1 下载免费PDF全文
The conventional virus isolation technique was compared with a 24-h shell vial centrifugation culture technique and with a 48-h tube culture method for the detection of cytomegalovirus (CMV) in MRC-5 cells. Of 200 clinical specimens tested, 41 were positive for CMV by at least one procedure. Indirect immunoperoxidase staining was positive for 32 (78.0%) of 41 specimens in the tube culture method and for 30 (73.2%) of 41 specimens in the shell vial centrifugation method. CMV was detected in 23 (56.1%) of 41 specimens by the development of cytopathic effect within 14 days. 相似文献
166.
Lovinger R Holland J Kaplan S Grumbach M Boryczka AT Shackelford R Salmon J Reid IA Ganong WF 《Neuroscience》1976,1(6):443-450
The role of brain catecholamines in the regulation of growth hormone secretion was investigated in pentobarbital-anesthetized dogs by using drugs which modify the function of adrenergic neurons and receptors. Intravenous administration of L-dopa produced a prompt, statistically significant increase in plasma growth hormone concentration. This response was not significantly reduced by blockade of peripheral dopa decarboxylase activity with carbidopa. Clonidine, an alpha-agonist which penetrates the brain, increased plasma growth hormone secretion. Norepinephrine, epinephrine, dopamine and isoproterenol, catecholamines which do not penetrate the blood-brain barrier, failed to affect plasma growth hormone concentration when administered intravenously. Apomorphine did not produce a statistically significant increase in plasma growth hormone concentration when administered directly into the the third ventricle, and pimozide failed to abolish the increase in plasma growth hormone produced by L-dopa. The increase in plasma growth hormone concentration produced by intravenous L-dopa and clonidine was prevented by administration of phentolamine or phenoxybenzamine directly into the third ventricle. The response to L-dopa was also abolished by intraventricular procaine. In dogs in which central beta-adrenergic blockade was produced by intraventricular L-propranolol, the growth hormone response to L-dopa was greater than it was in control dogs treated with intraventricular D-propranolol. The data indicate that in pentobarbital anesthetized dogs, the increase in growth hormone secretion produced by L-dopa is mediated by norepinephrine, rather than dopamine, that the site of action of the norepinephrine is central, above the median eminence and inside the 'blood-brain barrier', and that the norepinephrine acts via alpha-adrenergic receptors. 相似文献
167.
Periodic limb movements in sleep in community-dwelling elderly. 总被引:6,自引:0,他引:6
The prevalence of periodic limb movements in sleep (PLMS) in a randomly selected elderly sample is reported. In San Diego, 427 elderly volunteers aged 65 yr and over were recorded in their homes. Forty-five percent had a myoclonus index, MI greater than or equal to 5. Correlates of PLMS included dissatisfaction with sleep, sleeping alone and reported kicking at night. Although statistically significant, the strengths of the associations between interview variables and myoclonus indices were all small. No combination of demographic variables and symptoms allowed highly reliable prediction of PLMS. 相似文献
168.
Overproduction and purification of the luxR gene product: Transcriptional activator of the Vibrio fischeri luminescence system 下载免费PDF全文
Kaplan HB Greenberg EP 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(19):6639-6643
Expression of Vibrio fischeri luminescence genes requires an inducer, termed autoinducer, and a positive regulatory element, the luxR gene product. A plasmid containing luxR under control of a tac promoter was engineered to overproduce this gene product. The overproduced luxR gene product was active in vivo, and its apparent monomeric molecular weight was indistinguishable from that of the protein encoded by luxR under control of its own promoter (M(r) 27,000). The new tac-luxR construct directed the synthesis of large quantities of the luxR gene product in induced Escherichia coli cells lacking other lux genes. In the presence of the other lux genes, overexpression of the tac-luxR construct was not detected. The overproduced luxR gene product, which formed cytoplasmic inclusion bodies, was purified and used in subsequent studies. Nonequilibrium pH gradient electrophoresis indicated that the protein was basic, and the amino-terminal 15 amino acids were sequenced. DNA-binding activity was detected by membrane filter binding assays; under the conditions used, the binding was not lux DNA-specific. Binding of tritium-labeled autoinducer to the luxR gene product was not detected, and autoinducer enhancement of the binding of the luxR gene product to DNA could not be detected reproducibly. 相似文献
169.
170.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献