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91.
White matter lesions on computed tomography of the head were studied in relation to neuropsychological functioning in subjects from a representative sample of non-demented ( n = 134) and demented ( n = 98) 85-year-olds. Non-demented subjects with white matter lesions ( n = 46) scored significantly lower in tests of verbal ability (Synonyms), spatial ability (Block Design, Clock Test), perceptual speed (Identical forms), secondary memory (Thurstone Picture Memory), basic arithmetic (Coin Test) and the global cognitive screening test Mini-Mental State Examination than non-demented subjects without white matter lesions ( n = 88). Demented subjects with white matter lesions ( n = 67) scored significantly lower in tests of spatial ability (Block Design and Clock Test) and secondary memory (free recall in the MIR memory test, Ten-word memory test I and II) and in the Mini-Mental State Examination than demented subjects without white matter lesions ( n = 31). It is concluded that white matter lesions contribute to cognitive decline in both non-demented and demented elderly subjects.  相似文献   
92.
Warfarin is a commonly used oral anticoagulant that is usually initiated after the definitive diagnosis of a certain thromboembolic disorder or disease. Warfarin therapy will usually be prescribed for 6–12 weeks or more, and some patients may continue therapy throughout life, depending on the type of thromboembolic disorder. Major problems associated with warfarin therapy include adverse effects such as bleeding complications and drug-drug or drug-food interactions. In addition, thromboembolic complications may occur due to subtherapeutic dosages of warfarin. The laboratory reference standards for monitoring warfarin therapy are the prothrombin time (PT) and the International Normalized Ratio (INR). While both the PT or INR will reflect the clinical response in the patient, results reported as INR values have been shown to be more accurate than those reported as PT values. Thirty-two patients were enrolled in this study. Our objectives were to compare INR values measured by both the Coumatrak and conventional laboratory method, and to demonstrate the effects of pharmacist intervention on managing patients receiving warfarin therapy. Results from our study reveal that INR monitoring by Coumatrak is similar to the conventional laboratory method. In addition, our study indicates that patients receiving warfarin therapy can be monitored and managed effectively by pharmacists.  相似文献   
93.
The formation of 1.25-dihydroxycholecalciferol (1.25-(OH)2D3after single intravenous injections of 1-hydroxycholecalciferol(1-OHD3) was examined in four patients with chronic renal failureon regular haemodialysis. Following 1–3µg 1-OHD3administered at weekly intervals, 1.25-(OH)2D3 appeared in thecirculation within 1 h, and peak concentrations were reachedbetween 2 h and 5 h. By 8 h serum 1.25-(OH)2D3 concentrationshad started declining and by 44 h they had returned to baselineafter 1µg 1-OHD3 but they were still above basal after2 and 3 µg by an average of 30 pmol/l. One week afterinjections, concentrations were back to basal in all patientsstudied. The serum 1,25-(OH)2D3 dose response to injected la-OHDwas linear, indicating ample capacity of the liver 25-hydroxylaseto further hydroxylate 1-OHD. However, examination of the individualresponses revealed lower increments in serum 1.25-(OH)3 concentrationsin the patients with the highest basal serum 25-hydroxyvitaminD concen trations. Intravenous 1-OHD3 may be useful in the furtherstudy of the interactions between 1.25-(OH)23 calcium and PTHin chronic renal failure, as well as of the hepatic metabolismof vitamin D.  相似文献   
94.
It is generally accepted that the pattern electroretinogram for very large spatial elements is the result of local luminance stimulation. Responses due to the luminance differences between elements may be assumed to be relatively unimportant because in the case of large elements only few retinal units are stimulated by gradients. With decreasing pattern element size one wonders to what extent the electroretinogram continues to be based on the local luminance stimulation. We investigated this question using 8 Hz checkerboard reversal and compared the pattern recordings with the recordings resulting from the same stimulus field modulated homogeneously (focal electroretinogram). A 100% modulated checkerboard at retinal level may be considerably less modulated because of imperfect optics of the eye. So the pattern electroretinogram should be compared with homogeneous field stimulation of correspondingly lower modulation depth. On the basis of the optical transfer properties of the eye we compared by subtracting the proper focal electroretinogram from the pattern electroretinogram. The difference response was virtually zero for check sizes larger than 120. For checks from 60 down the difference response was of the same order of magnitude as the adjusted focal recording. This difference response for eyes with normal optics is largest around 30; its wave form was found to be rather invariant with check size.  相似文献   
95.
In the present study, 192 extremely anxious dental patients were asked for the factors which may have influenced their dental anxiety. The results showed that a traumatic dental experience, personality and professional behaviour of the dentist, persons in the direct environment, and psychological background all played an important role. Almost all extremely anxious dental patients had more than one negative experience with the dental treatment. Most patients acquired their anxiety at an early age.  相似文献   
96.
We have studied the effect of environmental sulfate concentration on the glycosaminoglycan synthesis of anatomically intact patellar cartilage of the mouse in vitro. Incubation of mouse patellae in medium with sulfate concentrations below 0.5 mM resulted in a diminished incorporation of sulfate but in unaltered incorporation of glucosamine. This suggested the synthesis of undersulfated glycosaminoglycans under these conditions. We characterized glycosaminoglycans synthesized at three different sulfate concentrations: a sulfate concentration physiological for the mouse (1.0 mM), a sulfate concentration in the range where sulfate incorporation was strongly diminished (0.1 mM), and an extremely low sulfate concentration (10 nM). Analysis of glycosaminoglycan disaccharides and DEAE anion chromatography of the glycosaminoglycans could not confirm the synthesis of undersulfated glycosaminoglycans at 0.1 mM. The chromatogram of glycosaminoglycans synthesized in medium containing 10 nM showed the presence of a very low sulfated glycosaminoglycan pool not observed at higher medium sulfate concentrations. Intermediately sulfated glycosaminoglycans were also synthesized during incubation with 10 nM sulfate. So, our data indicate that only very low sulfate concentrations in the medium lead to the synthesis of undersulfated glycosaminoglycans and that the sulfation mechanism of murine patellar cartilage chondrocytes does not seem to fit completely in an "all-or-nothing" pattern.  相似文献   
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99.
There is great interest in characterizing the proteins of the gastric pathogen Helicobacter pylori, especially those to which humans respond immunologically, because of the potential importance of such proteins in diagnosis and vaccine development. Two-dimensional gel electrophoresis was used to separate and identify potential antigens of H. pylori ATCC 43504. Over 30 proteins were reactive in Western blots with pooled sera from 14 infected patients. These proteins were analyzed by N-terminal sequence analysis. Fourteen proteins were determined to be distinct from any proteins previously described from H. pylori; the others were previously isolated and characterized proteins. Analysis of eight distinct H. pylori strains showed that most of these antigens were produced by all of the strains. We propose that collection of new antigens such as those recognized here will be useful in serologic tests for detecting and monitoring H. pylori infection and may also serve as potential targets for antimicrobial agent or vaccine development.  相似文献   
100.
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