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21.
22.
Carcinoma of the hepaticopancreatic ampullar region: role of US 总被引:3,自引:0,他引:3
Hepaticopancreatic ampullar tumors are so called because they are located at the confluence of the bile duct, pancreatic duct, and duodenum. Jaundice is an early sign of the disease and often leads to early diagnosis and favorable prognosis compared with other tumors that occur in this area. Of eight patients who underwent ultrasound (US) in the past 5 years, six (75%) were found to have tumor. The sizes of the tumors ranged from 1.6 to 2 cm. An intraluminal, polypoid mass in the distal part of the common bile duct was seen in four patients. In the other two patients, a sharply delineated mass gave rise to abrupt termination of the distal duct. Improved US resolution, more experience with this modality, and accurate diagnosis of these tumors with US will contribute to improved detection and prompt treatment. 相似文献
23.
V C Herson C Block L I Eisenfeld E Maderazo P J Krause 《American journal of perinatology》1992,9(4):285-288
The ability of the neonate to mount an adequate polymorphonuclear leukocyte (PMN) response, either quantitatively or functionally, is impaired. To assess whether neonatal PMN number and function are altered by labor and delivery, three groups of infants were studied: cesarean section without labor (10), cesarean section after labor (10), and vaginal delivery (11). PMN counts were higher in the groups undergoing labor (p less than 0.01) compared with the cesarean section without labor group. Similarly, the labor groups had evidence of complement activation (increased C3a desarg) compared with the cesarean section without labor group. No differences were noted between the groups in measures of PMN motility (chemokinesis or chemotaxis) or PMN degranulation (plasma lysozyme), suggesting that normal labor and delivery does not contribute to the general PMN dysfunction of the neonate. 相似文献
24.
Secretion of human hepatitis B virus is inhibited by the imino sugar N-butyldeoxynojirimycin. 总被引:8,自引:1,他引:7 下载免费PDF全文
T M Block X Lu F M Platt G R Foster W H Gerlich B S Blumberg R A Dwek 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(6):2235-2239
The imino sugar N-butyldeoxynojirimycin (NBDNJ) is a potent inhibitor of the oligosaccharide-trimming enzyme alpha-glucosidase I. Hepatitis B virus (HBV) contains three surface proteins (HBs proteins) of different sizes that are singly or doubly N-glycosylated and are essential for the formation of infectious virus. Therefore, the replication and secretion of HBV in the human hepatoma cell line HepG2 were studied in the presence of NBDNJ. In the stably HBV-transfected HepG 2.2.15 cells and in HBV-infected HepG2 cells, NBDNJ suppressed secretion of HBV particles and caused intracellular retention of HBV DNA. The secretion of subviral particles was less affected. These data suggest that inhibitors of oligosaccharide trimming may be useful for antiviral therapy of hepatitis B and for the study of the intracellular transport of the viral glycoproteins. 相似文献
25.
Identifying potential indicators of the quality of end-of-life cancer care from administrative data.
Craig C Earle Elyse R Park Bonnie Lai Jane C Weeks John Z Ayanian Susan Block 《Journal of clinical oncology》2003,21(6):1133-1138
PURPOSE: To explore potential indicators of the quality of end-of-life services for cancer patients that could be monitored using existing administrative data. METHODS: Quality indicators were identified and assessed by literature review for proposed indicators, focus groups with cancer patients and family members to assess candidate indicators and generate new ideas, and an expert panel ranking the meaningfulness and importance of each potential indicator using a modified Delphi approach. RESULTS: There were three major concepts of poor quality of end-of-life cancer care that could be examined using currently-available administrative data (such as Medicare claims): institution of new anticancer therapies or continuation of ongoing treatments very near death; a high number of emergency room visits, inpatient hospital admissions, or intensive care unit days near the end of life; and a high proportion of patients never enrolled in hospice, only admitted in the last few days of life, or dying in an acute-care setting. Concepts such as access to psychosocial and other multidisciplinary services and pain and symptom control are important and may eventually be feasible, but they cannot currently be applied in most data systems. Indicators based on limiting the use of treatments with low probability of benefit or indicators based on economic efficiency were not acceptable to patients, family members, or physicians. CONCLUSION: Several promising claims-based quality indicators were identified that, if found to be valid and reliable within data systems, could be useful in identifying health-care systems in need of improving end-of-life services. 相似文献
26.
Michael Schwarz Frank Block Rudolf Tpper Karl-Heinz Sontag Johannes Noth 《Annals of neurology》1992,32(3):358-364
Intrastriatal injection of quinolinic acid (QA) in rats provides an animal model that mimics some of the neuropathological and neurochemical alterations observed in the striatum of patients with Huntington's disease (HD). One of the very early neurophysiological signs in HD is a diminution of amplitude of early somatosensory evoked potentials (SEPs) recorded over the parietal cortex. The present study investigated whether the QA model exhibits similar neurophysiological abnormalities. Two weeks after unilateral intrastriatal injection of QA (240 nmol) or of the solvent, early SEPs were recorded with chronically implanted electrodes from the somatosensory cortex or from the ventrobasal nucleus of the thalamus of lightly pentobarbital-anesthetized rats, in response to single-shock electrical stimulation of the contralateral forepaw. Whereas intrastriatal injection of solvent did not influence SEPs, the striatal QA lesion significantly reduced the amplitude of early cortical SEPs by about 40% without affecting the latency. SEPs recorded from the ventrobasal nucleus were unchanged after QA lesion. Histological examination and glial fibrillary acid protein staining after intrastriatal injection of QA revealed no evidence for damage in the somatosensory system. It is concluded that (1) the QA animal model of HD mimics some of the SEP abnormalities of patients, and (2) a striatal lesion modulates somatosensory transmission to the cortex in rats. 相似文献
27.
28.
The deuterium nuclear spin relaxation times have been measured in tissues taken from rats given 20% deuterium oxide in their drinking water. The spin-lattice and spin-spin relaxation times were measured at 13.7 MHz by the inversion-recovery and Carr-Purcell-Meiboom-Gill FT methods, respectively. The reciprocals of the spin-lattice (T1) relaxation times were found to correlate well with those of protons in similar nondeuteriated tissues at a similar frequency (13.6 MHz) measured in a separate study. A least-squares analysis of the data yields (1/T1)H = (0.991)(1/T1)D - 3.48 for five tissues (standard deviations of 0.097 for the slope and 0.383 for the intercept with a correlation coefficient of 0.986). Implications with respect to relaxation mechanisms are discussed. 相似文献
29.
G. Todd Schulte MD Dr Franke E. Block Jr MD 《Journal of clinical monitoring and computing》1992,8(3):198-200
The introduction of the variable-pitch feature on pulse oximeters in 1983 by the Nellcor Corporation (Hayward, CA) allowed
users to rapidly detect changes in oxygen saturation by listening for changes in the pitch of the tones emitted by the pulse
oximeter. A few individuals have reported that they have been unable to detect a change in pitch when oxygen saturation changes.
To these individuals, the variable-pitch feature of these pulse oximeters has not been beneficial. Using the pitches from
one manufacturer of oximeters, we created a computer program to simulate the pitches that accompanied various oxygen saturations.
The pitches were recorded onto a tape player and played for 75 volunteer subjects unfamiliar with the pitches of a variable-pitch
pulse oximeter. Of our sample, 67% were able to detect a single change in pitch corresponding to a 1% fall in oxygen saturation,
and 11% of the population could not detect a change in pitch until there was a change in pitch with every beat. We suggested
four alternative designs that may prove beneficial to this group of individuals. 相似文献
30.
S H Block 《The Journal of allergy and clinical immunology》1974,53(4):243-244
Cromolyn sodium, a recently introduced antiasthmatic medication, is known occasionally to produce maculopapular and urticarial rashes, and increased bronchospasm. A patient is reported with a previously unpublished side effect of this medication, i.e., severe nasal congestion. 相似文献