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PURPOSE: The initiation and progression of noncarious cervical notch lesions (NCCL) continues to perplex clinicians worldwide and poses a considerable restorative challenge. The purpose of this brief communication is to report what is believed to be the first in vitro production of notch-shaped lesions in the cervical third of premolar teeth. MATERIALS AND METHODS: The lesions, were produced by axial loading of selected permanent premolar teeth in a 10% aqueous solution of sulfuric acid over a period of 5 days, followed by immersion in water for 7 days. RESULTS: Results revealed macroscopic and microscopic features similar to those observed in noncarious cervical lesions in vivo. The lesions were incidental findings while the authors were studying stress corrosion of enamel at low pH. Although much remains to be investigated regarding the etiology and pathogenesis of NCCL, axial loading and a corrosive environment may be implicated in these processes. The artificial lesions arose in clinically sound teeth, suggesting that there is no simple clinical examination to identify teeth at risk from NCCL. CLINICAL SIGNIFICANCE: The relationship between the development of NCCL and applied stress indicates that occlusal factors may play the most significant role in the initiation and progression of NCCL. 相似文献
44.
Czechowicz RT Reid CM Warren LJ Weightman W Whitehead FJ 《The Australasian journal of dermatology》2001,42(2):132-135
Two young men developed severe bullous eruptions with a distinctive clinical picture of severe flexural involvement and extensive mucosal ulceration. Biopsies showed subepidermal bullae and associated inflammation consisted of predominantly neutrophils. Both had IgG and C3 staining of the dermal-epidermal junction on direct immunofluorescence. Bullous pemphigoid was diagnosed on the basis of clinical, histopathological and immunofluorescence findings. Both cases occurred after recent ingestion of cephalexin. We believe they represent the first reported cases of bullous pemphigoid induced by cephalexin. 相似文献
45.
Perrine SA Whitehead TL Hicks RP Szarek JL Krause JE Simmons MA 《Journal of medicinal chemistry》2000,43(9):1741-1753
A set of novel tachykinin-like peptides has been isolated from bullfrog brain and gut. These compounds, ranatachykinin A (RTKA), ranatachykinin B (RTKB), and ranatachykinin C (RTKC), were named for their source, Rana catesbeiana, and their homology to the tachykinin peptide family. We present the first report of the micelle-bound structures and pharmacological actions of the RTKs. Generation of three-dimensional structures of the RTKs in a membrane-model environment using (1)H NMR chemical shift assignments, two-dimensional NMR techniques, and molecular dynamics and simulated annealing procedures allowed for the determination of possible prebinding ligand conformations. RTKA, RTKB, and RTKC were determined to be helical from the midregion to the C-terminus (residues 4-10), with a large degree of flexibility in the N-terminus and minor dynamic fraying at the end of the C-terminus. The pharmacological effects of the RTKs were studied by measuring the elevation of intracellular Ca(2+) in Chinese hamster ovarian cells stably transfected with the bullfrog substance P receptor (bfSPR). All of the RTKs tested elicited Ca(2+) elevations with a rank order of maximal effect of RTKA >/= SP > RTKC >/= RTKB. A high concentration (1 microM) of the neuropeptides produced varying degrees of desensitization to a subsequent challenge with the same or different peptide, while a low concentration (1 pM) produced sensitization at the bfSPR. Our data suggest differences in amino acid side chains and their charged states at the C-terminal sequence or differences in secondary structure at the N-terminus, which do not overlap according to the findings in this paper, may explain the differing degree and type of receptor activation seen at the bfSPR. 相似文献
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T Carlile K J Kopecky D J Thompson J R Whitehead F I Gilbert A J Present B A Threatt P Krook E Hadaway 《JAMA》1985,254(8):1050-1053
Mammographic parenchymal patterns have been proposed as a method of determining women at high risk of developing breast cancer. Wolfe's original report of relative risks as high as 37:1 for "dysplastic" breasts (DY) as compared with adipose breasts (N1), with intermediate values of P1 and P2, were not uniformly confirmed by others. (Relative risks are used here as the equivalent of odds ratios.) A case-control study of 706 breast cancers, each with two matching controls, drawn from 40,000 participants in four Breast Cancer Detection Demonstration Project clinics, was conducted to assess the role of the Wolfe classification of breast parenchymal patterns as a breast-cancer risk factor together with a set of well-established risk factors for breast cancer. Relative risks of 3.1 for DY to N1, 3.5 for P2 to N1, and 2.0 for P1 to N1 were determined. These are comparable to or greater than other known risk factors found in the same population. The Wolfe classification of parenchymal patterns strengthens the basis for clinical judgment, but should not be used exclusively to determine intervention in an individual patient's care. 相似文献
48.
This hospital phlebotomy team tackled their age-old turn around time (TAT) problem by implementing a technology that is becoming commonplace in a variety of businesses. Through the use of two-way communication headsets, this hospital laboratory significantly reduced TAT, improved service perceptions by the medical and nursing staffs, and diminished stress levels of the venipuncture team. 相似文献
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OBJECTIVES: To ascertain the reasons for not taking up a fall or injury prevention strategy among older people who have sustained a fall and attended an emergency department. SUBJECTS: As part of another trial, we identified 60 people who attended the emergency department of a public hospital with a fall. MAIN MEASURES: Participants were interviewed to ascertain the reasons for not taking up a falls prevention strategy, their falls-related health state, and the likelihood of them undertaking a falls and injury prevention strategy. RESULTS: A total of 31 (52%) of the participants had considered falls prevention after their fall. There were high levels of reluctance to undertake a strategy with 43 (72%) reluctant to take exercise classes, 10 (59%) reluctant to cease psychotropic medications, 26 (43%) reluctant to have a home safety assessment and 17 (28%) reluctant to take osteoporotic medication. When asked specifically about taking up a strategy to prevent a worsening health state, 19 (63%) of participants would take up exercise, 17 (57%) a home safety assessment, 4 of the 17 (59%) already taking implicated medications would stop and 56 (93%) would begin osteoporotic medication. These decisions did not alter when the goal for treatment was to improve a much worse health state. In participants with a lower starting health state, home safety assessments were viewed more favourably. CONCLUSIONS: There were significant obstacles to the implementation of most falls prevention guidelines examined. Treatment for osteoporosis was more acceptable to participants than exercise classes, cessation of psychotropic medication, and having a home safety assessment. Osteoporosis treatment, which had the least resistance, also had the least impact on the participants' lifestyle. 相似文献