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61.
BACKGROUND: Recurrent hyperparathyroidism may occur following parathyroid autotransplantation due to autogenous function of the muscle-engrafted tissue. Parathyroid lesions are uncommonly diagnosed on cytology. CASE: A 31-year-old female with chronic renal failure presented with an elevated parathyroid hormone level and a neck mass in the left sternocleidomastoid muscle, the site of a previous parathyroid autograft. Fine needle aspiration of the mass revealed high cellularity, with perivascularly arranged, three-dimensional, branching clusters; individual cells; and naked nuclei exhibiting anisonucleosis. A diagnosis of parathyroid graft hyperplasia was made by fine needle aspiration and subsequently by histopathologic examination. CONCLUSION: Fine needle aspiration is an effective tool for confirming the presence of parathyroid autograft hyperplasia, thus allowing the correct surgical approach.  相似文献   
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A problem of overprescribing of hypnotic medication ('sleeping tablets') was identified and quantified within a department of health care for older people in a district general hospital. Data on the volume of prescribing were obtained from computerized pharmacy records, and this information was supplemented by a retrospective survey of case notes of 100 patients. Sixty per cent of patients were prescribed a hypnotic at some stage during their hospital stay. Twelve per cent were prescribed a sleeping tablet on admission on an 'as required' basis but never took this medication, suggesting that such prescribing was becoming routine. As part of an ongoing pharmacy audit within the department, a policy was implemented to try to improve prescribing habits. Following this, hypnotic prescribing fell, with the average monthly number of sleeping tablets prescribed falling from 2392 to 734. A further survey of 100 case notes showed overall prescribing had fallen to 25%, although 2% were still prescribed a hypnotic on admission but never took it.  相似文献   
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The exocyclic base adduct 3,N4-deoxyethenocytosine (epsilonC) is a common DNA lesion that can arise from carcinogen exposure and/or as a biproduct of cellular processes. We have examined the thermal and thermodynamic impact of this lesion on DNA duplex properties, as well as the structural alterations imparted by the lesion. For these studies, we used calorimetric and spectroscopic techniques to investigate a family of 13-mer DNA duplexes of the form (5'CGCATGNGTACGC3')x(3'GCGTACNCATGCG5'), where the central NxN base pair represents the four standard Watson-Crick base pairs (corresponding to four control duplexes), and where either one of the N bases has been replaced by epsilonC, yielding eight test duplexes. Studies on these 12 duplexes permit us to assess the impact of the epsilonC lesion as a function of sequence context. Our spectroscopic and calorimetric data allow us to reach the following conclusions: (i) The epsilonC lesion imparts a large penalty on duplex stability, with sequence context only modestly modulating the extent of this lesion-induced destabilization. This result contrasts with our recent studies of duplexes with abasic sites, where sequence context was found to be the predominant determinant of thermodynamic damage. (ii) For the epsilonC-containing duplexes, sequence context effects are most often observed in the enthalpic contribution to lesion-induced duplex destabilization. However, due to compensating entropies, the free energy changes associated with this lesion-induced duplex destablization are nearly independent of sequence context. (iii) Despite significant lesion-induced changes in duplex energetics, our spectroscopic probes detect only modest lesion-induced changes in duplex structure. In fact, the overall duplex maintains a global B-form conformation, in agreement with NMR structural data. We discuss possible interpretations of the apparent disparity between the severe thermodynamic and relatively mild structural impacts of the epsilonC lesion on duplex properties. We also note and discuss the implications of empirical correlations between biophysical and biological properties of lesion-containing duplexes.  相似文献   
66.
Copolymers of aniline and toluidine were synthesized by oxidative chemical polymerization using different ratios of the monomers in the feed, and characterized by a number of techniques including UV–visible, IR, Raman, 1H NMR and EPR spectroscopies, as well as by thermogravimetric analysis and conductivity measurements. The properties of the copolymers are influenced by the amount of toluidine in the copolymer. Poly(o‐toluidine) and poly(m‐toluidine) are noticeably different in their solubility and conductivity. The copolymers show better solubilities than polyaniline but have lower conductivities. Differences in the properties of the salt and base forms of the copolymers are pointed out. Copyright © 2003 Society of Chemical Industry  相似文献   
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OBJECTIVE: To provide recommendations for the treatment of acquired immunodeficiency syndrome-related cytomegalovirus (CMV) end-organ diseases, including retinitis, colitis, pneumonitis, and neurologic diseases. PARTICIPANTS: A 17-member panel of physicians with expertise in clinical and virological research and inpatient care in the field of CMV diseases. EVIDENCE: Available clinical and virological study results. Recommendations are rated according to the quality and strength of available evidence. Recommendations were limited to the treatment of CMV diseases; prophylaxis recommendations are not included. PROCESS: The panel was convened in February 1997 and met regularly through November 1997. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although the epidemiological features of CMV diseases are changing in the setting of potent, combination antiretroviral therapy, continued attention must be paid to CMV diseases in patients infected with the human immunodeficiency virus to prevent irreversible endorgan dysfunction. The initial and maintenance treatment of CMV retinitis must be individualized based on the characteristics of the lesions, including location and extent, specific patient factors, and characteristics of available therapies among others. Management of relapse or refractory retinitis must be likewise individualized. Ophthalmologic screening for patients at high risk for retinitis or who have a prior diagnosis of extraretinal disease is recommended. Recommendations for gastrointestinal, pulmonary, and neurologic manifestations are included.  相似文献   
68.
The virion host shutoff (vhs) function of herpes simplex virus induces degradation of host mRNAs at early times and rapid turnover of viral mRNAs throughout infection. Previous studies have shown that disruption of the UL41 gene abrogates vhs activity, but have not determined whether the UL41 polypeptide is the direct inducer of mRNA degradation or whether it is the only virion component required for this activity. In this paper we report that transfection of cells with UL41 inhibits expression of a cotransfected CAT reporter gene and that the inhibition is not dependent upon other viral genes. Inhibition of CAT expression was due to UL41-dependent reduction of CAT mRNA levels. UL41 alleles encoding polypeptides that lacked vhs activity during virus infections exhibited a similar lack of activity in transfected cells. The results indicate that the UL41 polypeptide is the direct inducer of host mRNA degradation following virus infection and that it is the only virion component directly required for this activity. A 382-amino-acid nonsense polypeptide missing the last 107 residues of UL41 lacked inhibitory activity, but was packaged into virions, while a 343-amino-acid nonsense polypeptide lacked both inhibitory activity and the ability to be packaged.  相似文献   
69.
The aim of this study was to determine the effect of the lipid modifying agent gemfibrozil on lipid and coagulation risk factors in patients with Type 2 diabetes mellitus (Type 2 DM). Twenty-six subjects with Type 2 DM and dyslipidaemia were treated for 24 weeks with either gemfibrozil 600 mg orally twice daily or placebo in a double-blind randomized trial. Lipid profiles, fibrinogen, Factor VII, and plasminogen activator inhibitor-1 (PAI-1) were measured by routine laboratory methods. Low density lipoprotein (LDL) size was determined by gradient gel electrophoresis and the resistance of LDL to copper-induced oxidation was assessed by measuring absorbance at 234 nm. Gemfibrozil significantly reduced total cholesterol (-0.9 (-0.48, -1.32) mmol l(-1); p < 0.05) and triglycerides (-2.7 (-1.55, -1.35) mmol l(-1); p < 0.001) vs placebo. The fall in triglyceride was reflected by a fall in VLDL cholesterol levels in the gemfibrozil treated group vs placebo (-1.31 mmol l(-1); p < 0.001). LDL-cholesterol level did not change but LDL particle size increased by 0.5 nm (0.01, 0.93); P < 0.02. The increase in particle size was inversely correlated with the change of triglyceride level (r = -0.79, p < 0.0001) but did not result in any reduction of susceptibility to copper-induced oxidation. There were no significant changes in the coagulation parameters studied. Because of its ability to correct the lipid abnormalities associated with Type 2 DM particularly hypertriglyceridaemia, gemfibrozil provides a useful therapeutic option in the management of diabetic dyslipidaemia but it does not alter in vitro oxidizability of LDL.  相似文献   
70.
1-, 3-, and 6-nitrobenzo[a]pyrene (nitro-BaP) are environmental contaminants that can be metabolized to genotoxic derivatives by either nitroreduction or ring-oxidation. In this study, we examined the types of mutations produced by the primary nitroreduced metabolites, 1-, 3-, and 6-nitroso-BaP (NO-BaP) in the hprt gene of Chinese hamster ovary cells. RNA from 6-thioguanine-resistant mutants was reverse-transcribed to cDNA and the hprt coding sequence was amplified and sequenced. The mutational patterns produced by the three compounds exhibited extensive similarities: 1) base pair substitutions accounted for 67% (28/42) of 1-NO-BaP, 51% (26/51) of 3-NO-BaP, and 50% (11/22) of 6-NO-BaP mutations; 19-36% of the mutations were exon deletions and 14-18% were frameshifts; 2) most (64-84%) of the simple base pair substitutions occurred at G:C, mainly G:C-->T:A and G:C-->C:G transversions; 3) 98% (46/47) of the simple base pair substitutions at G:C had the mutated dG on the non-transcribed strand and 81% (38/47) were located with the mutated dG flanked 3' by at least one purine; and 4) most simple base pair substitutions (48/62, 77%) occurred in exons 2, 3, and 8 of the hprt gene. Although there were no significant differences among the mutation profiles of the NO-BaPs, a significant difference did exist between the mutation pattern produced by 3-NO-BaP and the mutation pattern previously determined for the ring-oxidized product of 3-nitro-BaP metabolism, trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9, 10-tetrahydro-3-nitrobenzo[a]pyrene. This observation indicates that differences in the structures of closely related adducts can be important enough to have an effect on mutation profiles.  相似文献   
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