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991.
992.
J. Bertram 《Archiv der Pharmazie》1975,308(3):195-202
Reactions of Diphenylcarbinols with Phosphoric Acid In contrast to the reaction of 1,1-diphenyl-2-methyl-2-aminopropanol-(1) (1) with phosphoric acid to 2-amino-2-(9-fluoreno)-propane (2) , no analogous reaction is observed with various 1,1-diphenylcarbinols; rearrangement and elimination reactions are found. The products of these reactions are investigated mainly by NMR- and mass spectrometry. 相似文献
993.
994.
L S Kamaraju P H Levine S K Sundar D V Ablashi A Faggioni G R Armstrong G Bertram G R Krueger 《Journal of the National Cancer Institute》1983,70(4):643-647
It is demonstrated in this study that a serum factor, a lymphocyte stimulation inhibitor (LSI), which inhibits Epstein-Barr virus (EBV)-induced lymphocyte stimulation, is a potentially useful tool in the diagnosis and monitoring of nasopharyngeal carcinoma (NPC). In a study of 25 patients with undifferentiated NPC, 20 healthy controls, and 20 patients with other head and neck tumors, LSI was found only in the NPC patients with active disease. In a more complete study of 8 patients longitudinally followed up for at least 20 months, a comparison of LSI with antibodies to a variety of EBV antigens including viral capsid antigen, early antigen, and nuclear antigen indicated that LSI levels provided a reliable and sensitive indicator of disease activity that should be added to clinical markers currently in use as monitors of disease activity in NPC. 相似文献
995.
996.
D A Bertram D A Opila J L Brown S J Gallagher R W Schifeling I S Snow C O Hershey 《Medical care》1992,30(2):95-104
This study examined the reliability and validity of a brief six-item instrument to measure the mental workload experienced by residents for specific patient visits to an ambulatory care clinic. Participating in the study were twenty-two residents in postgraduate years 1 through 3 who were working in the general outpatient clinic of an inner city, private, nonprofit community hospital. Cronbach's alpha coefficient for the instrument was 0.80. Findings supported several theory-based hypotheses on determinants and performance consequences of mental workload. Mental workload was positively correlated with fatigue (r = 0.42, P = 0.03) and inversely correlated with residents' self-rated experience with patients' problems (r = -0.65, P less than 0.001). Residents' performance was measured through self-ratings and faculty physicians' ratings. Mental workload was inversely correlated with self-rated performance (r = -0.67, P less than 0.001). The correlation of mental workload with faculty physician ratings that reflected the technical dimension of patient care (physician examination, medications, and procedures) was r = -0.38 (P = 0.04). With mental workload squared, the correlation was r = -0.45 (P = 0.02) and the form of the relationship, consistent with the hypothesis, was a slightly downward sloping curve. Limitations of this research are discussed as well as suggestions for further research. 相似文献
997.
The methods presented in this paper grew out of the current need for a more quantitative approach to immunocytochemistry. The problem was approached by exploiting the high affinity of biotin for avidin in the design of radioimmunocytochemical methods using [3H]biotin. [3H]Biotin and avidin D form a radioactive complex which can be linked onto a primary antibody by means of a biotinylated anti-rabbit IgG or biotinylated protein A link. With both approaches it was possible to localize a number of antigens such as somatostatin, substance P, avian pancreatic polypeptide, tyrosine hydroxylase, and enkephalin-like immunoreactivity in various regions of the rat and human brain. By using tritium-sensitive film, large regions of the brain could be studied and analyzed semiquantitatively using computerized microdensitometry. The technique was also taken to the electron microscopic level, and in the case of substance P immunoreactivity within the rat substantia nigra silver grains were found to be highly localized over axons and axon terminals. It was also possible to demonstrate co-existence or lack of co-existence of a number of different antigens within neurones. The first primary antibody was localized with biotinylated protein A followed by avidin-peroxidase, while the second primary antibody was linked to the [3H]biotin again with biotinylated protein A. As an example of the potential of these methods for semiquantification, the distribution of substance P within postmortem human spinal cord was examined 24 months after amputation. A 49% loss of peptide was found in the corresponding dorsal horn. In summary these methods using [3H]biotin have proved successful in quantification, electron microscopy and double labelling studies. 相似文献
998.
Emshoff R Innerhofer K Rudisch A Bertram S 《International journal of oral and maxillofacial surgery》2001,30(2):118-122
In terms of clinical decision-making in instances of temporomandibular disorders (TMD) and orofacial pain, there is controversy in the literature over the diagnostic significance of the temporomandibular joint (TMJ)-related variable disk-condyle relationship (DCR). The purpose of this study was to investigate whether in patients with TMJ-related pain, the variable of TMJ pain may be linked to magnetic resonance (MR) imaging findings of internal derangement (ID). The study comprised 163 consecutive TMJ pain patients. Criteria for including a patient were report of orofacial pain referred to the TMJ, and the presence of uni- or bilateral TMJ pain during palpation, during function, and/or during unassisted or assisted mandibular opening. Bilateral sagittal and coronal MR images were obtained to establish the prevalence of TMJ ID types. Analysis of the data revealed the presence of TMJ pain to be associated with significantly more MR imaging diagnoses of ID than an absence of ID (P<0.001), and disk displacement without reduction than disk displacement with reduction (P<0.001). Using chi-square analysis, the results showed a significant relationship between the presence of TMJ-related pain and the MR imaging diagnosis of TMJ ID (P=0.001), and TMJ ID type (P=0.000). Use of the Kappa statistical test indicated poor diagnostic agreement between the presence of TMJ pain and the MR imaging diagnosis of ID (K=0.16). The results suggest that the clinical variable of TMJ pain may have a significant effect on the prevalences of MR imaging diagnoses of TMJ ID. The data confirm the biological concept of DCR as a diagnostic approach in patients with signs and symptoms of TMJ-related pain. 相似文献
999.
1000.