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101.
102.
Many questions about analgesic nephropathy (AN) lack clear-cut answers. We present available evidence for and against proposed answers to many of these questions. These include: (1) Is acetaminophen (AC) nephrotoxic when taken as the sole analgesic? (2) Is the combination of acetylsalicylic acid (ASA) and AC more nephrotoxic than AC taken alone, and if so, why? (3) What are the minimum doses and durations of ingestion required to produce analgesic nephrotoxicity? (4) Is the combination of ASA and AC (a major metabolite of phenacetin) less nephrotoxic than that of phenacetin and ASA combined? (5) Does caffeine in combination with analgesics contribute to nephrotoxicity? (6) What is the incidence of end-stage renal disease (ESRD) due to AN? (7) What uniform diagnostic criteria should be established for AN? (8) What are the earliest anatomic and biochemical abnormalities? (9) What are the mechanisms of renal injury? (10) Does AC cause uroepithelial neoplasia? (11) What research might be most beneficial? Based mainly on associations, some strong, we suggest that AN still exists as a cause of ESRD in the United States, where AC/ASA combinations are available over the counter, and in Canada, where they are not. We also suggest that the evidence needed to recommend that the AC/ASA combination be excluded from over-the-counter analgesic preparations still has limitations. A prospective multicenter study comparing incidence related to AC/ASA in the United States and to AC in Canada and the United States may be needed to answer this question. For such a study to be worthwhile, an adequate incidence in both countries is required. 相似文献
103.
F. van Eylen MH Antoine P. Lebrun and A. Herchuelz 《Fundamental & clinical pharmacology》1994,8(5):425-429
Summary— Na/Ca exchange was recently shown to regulate cytosolic free Ca2+ concentration ([Ca2+ ]i ) in the pancreatic B-cell. The aim of the present study was to provide direct evidence that inhibition of the activity of the exchange may also increase insulin release. In the presence of extracellular Na+, caffeine stimulated 45 Ca outflow but did not increase insulin release from islets perifused in the presence of 2.8 mM glucose. By contrast, in the absence of extracellular Na+, caffeine almost failed to increase 45 Ca outflow and reversibly stimulated insulin release despite the fact that the absence of extracellular Na+ per se reduced basal insulin release. Similar findings were observed in islets perifused at a higher glucose concentration (8.3 mM) except that, in the presence of extracellular Na+, caffeine more markedly increased 45 Ca outflow and stimulated insulin release. Our data provide direct evidence that inhibition of Na/Ca exchange with resulting blockade of Ca2+ outflow may increase insulin release from the pancreatic B-cell under suitable experimental conditions. 相似文献
104.
A prospective study of symptomatic bacteremia following platelet transfusion and of its management 总被引:6,自引:0,他引:6
EK Chiu ; KY Yuen ; AK Lie ; R Liang ; YL Lau ; AC Lee ; YL Kwong ; S Wong ; MH Ng ; TK Chan 《Transfusion》1994,34(11):950-954
BACKGROUND: The danger of bacteremia due to contaminated platelets is not well known. There are also no established guidelines for the management of febrile reactions after platelet transfusion. STUDY DESIGN AND METHODS: To determine the risk of symptomatic bacteremia after platelet transfusion, 3584 platelet transfusions given to 161 patients after bone marrow transplantation were prospectively studied. Platelet bags were routinely refrigerated for 24 hours after transfusion. Septic work-up was initiated for a temperature rise of more than 2 degrees C above the pretransfusion value within 24 hours of platelet transfusion or a temperature rise of more than 1 degree C that was associated with chills and rigor. Diagnosis of bacteremia after platelet transfusion was made only when the pairs of isolates from the blood and the platelet bags were identical with respect to their biochemical profile, antibiotic sensitivity, serotyping, or ribotyping. RESULTS: Thirty-seven febrile reactions, as defined above, occurred. Bacteremia subsequent to platelet transfusion was diagnosed in 10 cases. There was a 27-percent chance (95% CI, 15–43%) that these febrile reactions represented bacteremia that resulted from platelet transfusion. For a subgroup of 19 patients with a temperature rise of more than 2 degrees C, the risk of bacteremia was 42 percent (95% CI, 23–64%). Septic shock occurred in 4 of the 10 bacteremic patients. A rapid diagnosis was possible because the involved bacteria were demonstrated by direct Gram stain of the samples taken from the platelet bags of all 10 patients. CONCLUSION: Significant febrile reactions after platelet transfusion are highly likely to be indicative of bacteremia. Routine retention of platelet bags for subsequent microbiologic study was useful in the investigation of these febrile reactions. Empiric antibiotic therapy is indicated. 相似文献
105.
106.
Seventy-one clinics in the UK offering in-vitro fertilization (IVF)
treatment were surveyed for their protocols on the assessment of the
welfare of the children produced. A total of 44 (62%) responded. Of these,
five (12%) did not have operational protocols, seven (16%) declined to
provide their protocols, and 32 (73%) provided information used in the
survey. The information was in the form of a protocol for only 16 (50%) of
these clinics. The remaining clinics submitted as their 'protocols' letters
to general practitioners, patient information, patient questionnaires
and/or a copy of their policy on the assessment of child welfare. From the
submitted material, it was possible to determine that 94% of clinics seek
information on aspects of child welfare assessment, 78% have a procedure
for making further enquiries where there is any cause for concern, 44 %
include counselling opportunities explicitly in protocols, 30-38% of
clinics see a full medical and social history from each prospective parent
as part of the child welfare assessment, 16% include explicit consideration
of the impact of multiple births on the welfare of the child, and 3%
include consideration of the issue of disclosure of the mode of conception
of the child on its welfare. Most clinics did not have clearly defined
procedures on how to reach a decision on whether or not to treat. Eight
clinics (25%) made explicit in their protocols any exclusion criteria. It
is concluded that clinics are not currently producing completely effective
protocols. Two possible reasons for this are considered: lack of technical
knowledge about what constitutes an effective protocol, and lack of clear
policy development and propagation underlying protocols within clinics.
Possible approaches to improving the situation are considered.
相似文献
107.
108.
Comparison of iohexol with metrizamide in myelography 总被引:2,自引:0,他引:2
109.
Pancreas divisum: thin-section CT 总被引:1,自引:0,他引:1
Zeman RK; McVay LV; Silverman PM; Cattau EL; Benjamin SB; Fleischer DF; Garra BS; Jaffe MH 《Radiology》1988,169(2):395-398
Twelve patients with known pancreas divisum underwent thin-section computed tomography (CT) to determine the capability of CT to depict this pancreatic anomaly. Focal pancreatic enlargement was present in five patients. Two distinct pancreatic moieties separated by a fat cleft were noted in three patients; a fourth patient had focal atrophy in the distribution of the dorsal pancreas. The two pancreatic moieties were identified at the same craniocaudal level in all four of these patients. The dorsal duct was depicted in all 12 patients, while the short ventral duct was seen in only five of the 12 patients. Failure of the ventral and dorsal pancreatic ducts to fuse was identified in all five patients in whom both ducts were seen. CT may not enable specific diagnosis of pancreas divisum in the majority of patients. If, however, distinct pancreatic moieties or unfused ductal systems are evident, the diagnosis may be confidently suggested. 相似文献
110.