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21.
J R Shepherd 《Journal of cataract and refractive surgery》1989,15(3):335-339
Opacification of the posterior capsule and lack of intraocular lens fixation have been recurring problems and have resulted in a gradual shift from sulcus-fixated silicone lenses to bag-fixated silicone lenses. Postoperative capsular contraction, however, can cause capsular tearing in the periphery and intraocular lens decentration. A new method of combining a small circular capsulotomy, cataract removal without anterior capsular rim tearing, and meticulous bag placement of the silicone lens seems to allow centering and secure fixation of the silicone lens. 相似文献
22.
Tamoxifen and the gynaecologist 总被引:1,自引:1,他引:0
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24.
Rapid differentiation of the major causative agents of bacterial meningitis by use of frequency-pulsed electron capture gas-liquid chromatograph: analysis of acids. 下载免费PDF全文
The major causative agents of bacterial meningitis, Haemophilus influenzae serogroup B, Neisseria meningitidis serogroups B and C, Klebsiella pneumoniae, Streptococcus pneumoniae, and two types of Escherichia coli, were cultured in a modified chemically defined Catlin medium and in a commercial version of the unmodified Catlin medium. The spent media were extracted under acidic conditions, and electron-capturing derivatives were prepared by derivatization with trichloroethanol or haptafluorobutyric anhydride. The derivatives were analyzed on a gas chromatograph equipped with a frequency-pulsed electron capture detector and a PEP-2 computer. The data obtained from the study show that these organisms can be easily distinguished from each other on the basis of metabolic products detected in either type of medium. Three different metabolic groups were detected within two serogroups of N. meningitidis. The methods are practical, and the new technique should offer clinical laboratories and hospitals a better method for rapid identification of this important group of pathogens. 相似文献
25.
R Abdolrasulnia V L Shepherd 《American journal of respiratory cell and molecular biology》1992,7(1):42-48
Two receptors for tumor necrosis factor-alpha (TNF) were purified from detergent-solubilized human lung tissues by adsorption to TNF-Sepharose, followed by elution with low pH. By SDS-PAGE analysis, the two proteins had molecular weights of 75 and 55 kD. Using a soluble receptor assay, a binding affinity of approximately 1.2 nM was calculated for the isolated lung receptors. Each protein, isolated by electroelution from polyacrylamide gels, specifically bound TNF. Antibodies raised against the mixture of type I and II receptors bound specifically to both purified receptors by immunoblot analysis. Both the 75- and 55-kD receptors could be precipitated from 125I-surface-labeled or 35S-methionine-labeled U937 cells using TNF-Sepharose or anti-receptor antibodies. In addition, the anti-TNF receptor antibodies partially blocked binding of TNF to U937 cells and specifically immunoprecipitated 125I-TNF cross-linked to its receptors on U937 cells. These results demonstrate that both type I and II TNF receptors can be isolated from human lung tissue by ligand affinity chromatography, and that U937 cells express both TNF receptor types. 相似文献
26.
Detection of human papillomavirus type 16 DNA in carcinomas of the palatine tonsil. 总被引:1,自引:1,他引:1 下载免费PDF全文
G Niedobitek S Pitteroff H Herbst P Shepherd T Finn I Anagnostopoulos H Stein 《Journal of clinical pathology》1990,43(11):918-921
Twenty eight tonsillar carcinomas of various histological types were investigated for the presence of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human papillomavirus (HPV) types 6, 11, and 16 by in situ hybridisation using highly stringent procedures. In six cases an autoradiographic signal was obtained in the tumour cell nuclei with the HPV type 16 specific probe. No signal was obtained with any of the other probes. Immunohistochemical investigations with mouse monoclonal antibodies directed against the L1 protein of HPV type and a rabbit antiserum that detects common protein determinants of HPV gave negative results, thus indicating latent infection. Furthermore, a series of tonsils from controls with comparable age distribution was negative by both in situ hybridisation and immunohistology. These results indicate a possible role for HPV 16 in the aetiology of a proportion of tonsillar carcinomas. 相似文献
27.
Rapid differentiation of the major causative agents of bacterial meningitis by use of frequency-pulsed electron capture gas-liquid chromatography: analysis of amines. 总被引:1,自引:8,他引:1 下载免费PDF全文
The major causative agents of bacterial meningitis (Haemophilus influenzae serogroup B, Neisseria meningitidis serogroups B and C, Klebsiella pneumoniae, Steptococcus pneumoniae, and two types of Escherichia coli) were cultured in a chemically defined medium, and selected strains were further studied in Todd-Hewitt medium. After acidic extraction of the spent media with chloroform, a basic extraction was made with chloroform to obtain amines. A third extraction was performed on re-acidified Todd-Hewitt medium with ethyl ether to obtain hydroxyacids. The extracts were derivatized with heptafluorobutyric anhydride-ethanol to form electron-capturing derivatives, and the derivatives were analyzed on a frequency-pulsed electron capture gas-liquid chromatograph (FPEC-GLC) equipped with a PEP-2 computer. The data obtained from the study showed that amines were produced by these organisms that formed characteristic patterns. Different serotypes of K. pneumoniae and the two serogroups of N. meningitidis produced different types of FPEC-GLC profiles within serotypes. E. coli produced several hydroxy acids on Todd-Hewitt medium that made it unique among the organisms studied. The methods used are practical and the techniques have potential for use in clinical laboratories and hospitals as a valuable aid for the rapid identification of the major causative agents of bacterial meningitis. 相似文献
28.
A whole body plethysmograph (body box) equipped with a flow meter (see Figure 1) was used for objective quantification of the effects of single doses of clemastine fumarate 2.68 mg, chlorpheniramine 4 mg and placebo in a double-blind study of 48 patients with seasonal allergic rhinitis. This technique offers an objective means of assessing drug effects on nasal congestion and obstruction. Before the development of whole body plethysmography, only subjective assessments of antihistamines' effects on nasal blockage or congestion were available. These subjective reports usually noted that nasal blockage or congestion was refractory to antihistamines or minimally relieved by them. However, in this study, nasal and oral airway resistances, each measured by whole body plethysmography, were lowered by clemastine fumarate and chlorpheniramine. These results were corroborated by the patients' and physician's assessments of changes in symptom severity and the physician's evaluation of intranasal photographs taken for each patient. Oral airway resistance of patients treated with clemastine fumarate was improved to a significantly greater extent than in patients receiving placebo. At two hours post-drug, patients receiving clemastine fumarate usually showed a greater response in most assessments than those receiving chlorpheniramine, and the trend of most comparisons was clearly in favor of clemastine fumarate. Patients in all three treatment groups experienced drowsiness but both incidence and severity were lower with clemastine fumarate. 相似文献
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30.
Evidence from a controlled, comparative trial indicates that oral pimozide is clinically at least as effective as depot injections of fluphenazine decanoate in the continuation therapy of a group of schizophrenic patients discharged from hospital. The administration of pimozide was associated with fewer unwanted effects. The implications of the findings are discussed. 相似文献