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31.
BACKGROUND: Proton pump inhibitors are known to decrease the activity of Helicobacter pylori organisms within the stomach and to shift their distribution proximally. This effect may reduce the sensitivity of histological examination and rapid urease testing for H. pylori on biopsies taken from recommended sites. It is of particular relevance if a proton pump inhibitor has been prescribed before the patient has undergone diagnostic endoscopy. METHODS: We studied patients referred to our open-access upper gastrointestinal endoscopy service who had either been on no medication (controls) or were already taking proton pump inhibitors. Biopsies taken from the gastric antrum and corpus were used for rapid urease testing and for histological examination. Sera, taken from patients who had no evidence of H. pylori in biopsies, were tested for IgG H. pylori antibodies as an alternative indicator of infection. RESULTS: H. pylori organisms were detected by histological examination in 27 of 40 controls (68%) and in 13 of 25 patients taking proton pump inhibitors (52%). Among patients with positive histology (organisms detected in either antral or corpus biopsies, or both), only the sensitivity of the antral urease test read at 1 h was significantly lower in patients taking proton pump inhibitors than in controls, with no significant difference in sensitivities of the antral urease test at 24 h, of the corpus urease test at 1 or 24 h, or of histology from the antrum or corpus. Of patients with negative histology, none of 13 controls compared with six of 12 patients taking proton pump inhibitors (50%) had positive serology (P = 0.005). Five (83%) of the six histology-negative, seropositive patients taking proton pump inhibitors had histological changes consistent with H. pylori gastritis even though no organisms were detected. CONCLUSIONS: Treatment with a proton pump inhibitor before endoscopy reduces the sensitivity of antral and corpus biopsies for H. pylori detection, both by urease testing and histological examination. If proton pump inhibitors already prescribed cannot be discontinued for an adequate period before endoscopy, patients should have biopsies taken from the corpus as well as from the antrum, and serum should be tested for H. pylori.  相似文献   
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Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying.  相似文献   
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PURPOSE: Parkinson's disease (PD) is a chronic progressive neurological disorder that frequently results in nearly total disability. This study examined changes over 3 years in patients' experiences living with PD, and explored how participants' health perceptions and predicted mortality at baseline related to their actual death by Year 3. DESIGN AND METHODS: Data were obtained from a local sample of 109 participants by in-home interviews. RESULTS: The collected results (1) suggested a disconnection between the participants' responses to open-ended questions about the disorder, compared with their responses to questions structured by the investigators; (2) demonstrated changes in responses to structured and open-ended questions; and (3) demonstrated that respondents who declined to predict whether they would be living in 10 years were three times more likely to die by Year 3 than those who answered the question. IMPLICATIONS: Results demonstrate the importance of identifying the most important issues for the individual with PD and suggest that these issues may change over time. Results also raise issues surrounding how patients' perceptions influence the course of their disease.  相似文献   
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Several observations noted by early investigators supported the supposition that in most cases, congenital glaucoma is determined by genetic factors. The genetic heterogeneity of PCG was confirmed by genetic linkage studies conducted in the 1990s when the authors determined that CYP1B1 is the congenital glaucoma gene at the GLC3A locus. The coding sequence of CYP1B1 has been subjected to extensive screening in familial and sporadic cases of glaucoma from numerous countries and from a large number of ethnic groups. These studies have provided evidence for extensive allelic heterogeneity at the GLC3A locus. This article also discusses the molecular evidence for reduced penetrance in congenital glaucoma and the phenotypic heterogeneity of CYP1B1 mutations, mouse models of CYP1B1, and the biochemistry of CYP1B1.  相似文献   
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Telemedicine is becoming a subset of information science and should benefit tremendously from the geometric growth of information architecture in hospitals. The use of telemedicine to break the isolation of the operating room is a highly achievable goal. An open operating room has information on demand for the personnel, fluid communication among operating room personnel, and broad interaction with the learner community and consultants. In an operating room with significant data capture, the patient is brought into the process not only as a real person, but also as a huge data set that acquires all the events of the surgery. The data include the visual, electrical, and mechanical events that define the surgical procedure. As part of a dynamic electronic medical record, they are available to those who are present and those who are asked to help from even a great distance away with real-time advice. The data are also available to those who seek to understand what happened to the patient afterwards for the purpose of root cause analysis, near miss analysis, instruction, or more accurate medical records.  相似文献   
40.
Minor hematochezia after transrectal ultrasound and prostate needle biopsy is well reported. We present a case report of a 64-yr-old man on aspirin and with poorly controlled hypertension who developed severe hematochezia requiring blood transfusion. The bleeding was stopped with digital compression. The literature on hemorrhagic complications after prostate needle biopsy is reviewed.  相似文献   
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