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1.
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
2.
Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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The bioavailability of enteric coated and plain aspirin tablets was studied in four beagle dogs. Blood sampling for enteric coated tablets was planned with the aid of a radiotelemetric system. The release of aspirin from its dosage form was detected by monitoring the change in intestinal pH. Aspirin and salicylic acid levels in plasma obtained from the enteric coated dosage form exhibited familiar concentration versus time absorption profiles. Variation in the plasma concentrations of these two compounds within each dog studied (four runs each) was relatively small when time zero was adjusted to the commencement of tablet dissolution. The plasma levels obtained from plain aspirin (three runs each), however, show atypical absorption. The estimated absolute bioavailability was 0.432 +/- 0.0213 and 0.527 +/- 0.0260 for enteric coated and plain aspirin, respectively. Other pharmacokinetic parameters for these two dosage forms such as the highest observed plasma concentration (Cmax) (10.9 +/- 0.535 microgram/mL versus 13.6 +/- 1.88 micrograms/mL) and the time to reach Cmax (tmax) (26.6 +/- 1.94 min versus 31.0 +/- 7.04 min) agree well. The mean values for gastric emptying time, in vivo coating dissolution time, and in vivo disintegration/dissolution time of the tablet core for enteric coated aspirin are 48.7 +/- 7.23 min, 44.3 +/- 3.80 min, and 34.7 +/- 2.04 min, respectively.  相似文献   
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Younger women smoke at disproportionately higher rates than other women and their smoking has a major impact on the health of their young children. To address this problem, a smoking cessation intervention combining minimal advice and assistance from a community health nurse and a tailored self-help guide was developed for low-income women with young children. The program evaluation results reported here were gathered from women using publicly funded pediatric services in four agencies with 32 clinic sites in central and eastern Pennsylvania. Unlike volunteers in formal cessation programs, the women varied widely in their readiness to quit smoking. Follow-up data were obtained from 1,230 female smokers, aged 18 to 39, after receiving brief, individualized smoking cessation advice and encouragement to read the self-help guide. One year later, 12.5 percent reported quitting smoking, and 20.2 percent reported having made a serious quit attempt that lasted at least 7 days. These results suggest that, even among smokers with low socioeconomic status and wide variation in their readiness to quit, minimal intervention programs requiring modest resources can promote cessation.This work was funded under contracts from the Cancer Control Program, Pennsylvania Department of Health (SPC-883141 and SPC-979425). The Quitting Times STOP IT quit smoking protocol was adapted from the Smoking Cessation Project, Maternal and Child Health, Massachusetts Department of Public Health. The authors also wish to express appreciation to the staff of the Division of Population Science, Fox Chase Cancer Center for their contributions to this project and especially those of Chris Jepson, Eunice King, C. Tracy Orleans, and Marjorie Utt.  相似文献   
7.
A serious shortage of psychiatrists trained to care for mentally retarded patients exists. Based on a successful program that has been in place for more than a decade, the authors offer guidelines for training psychiatric residents in the diagnosis and treatment of mental illness in mentally retarded persons. They describe a model curriculum and suggest ways to modify existing four-year curricula. Special diagnostic skills for working with this population, such as posing questions in concrete terms and ruling out the effects of disabilities like seizure disorders, are reviewed. Important treatment issues include knowing the side effects of neuroleptics and understanding the stages through which families and other caregivers pass in accepting a person's mental retardation.  相似文献   
8.
The preoperative assessment of the high risk patient undergoing noncardiac surgery has traditionally been based on history, physical examination, and preoperative testing. We propose a method of assessing preoperative risk based on the presentation of coronary artery disease, exercise tolerance, and extent of the surgical procedure. Since this is an evolving field, as new information and perioperative management techniques become available, the preoperative evaluation of the high risk patient will change. We have presented one approach based on our interpretation of data from the current anesthesiology and cardiology literature. In the patient with a recent MI, the predischarge symptom-limited stress test and the electrocardiographic classification can be used to better stratify risk. In the patient with angina, testing should be reserved for those patients who are candidates for coronary revascularization or alternative surgical procedures. In the patient at risk of but without overt symptoms of coronary artery disease, the number of clinical risk factors can determine the probability of coronary artery disease in the individual patient. The decision to perform preoperative revascularization should be based on its anticipated improvement of both the short- and long-term prognosis of the patient considering the risk of such procedures. The objective assessment of LVEF should be performed in patients with a poor exercise tolerance with either a high risk of perioperative ischemia or a suspicion of cardiomyopathy.  相似文献   
9.
BACKGROUND--A circadian pattern has been convincingly demonstrated for the onset of many outpatient ischemic vascular events. A morning peak exists for the onset of acute myocardial infarction, sudden cardiac death, reversible myocardial ischemia, and ischemic stroke. Data regarding circadian patterns of disease in hospitalized patients, however, are lacking. We examined in-hospital cardiopulmonary arrest (CPA) occurring on the general medical ward to determine if a circadian distribution existed in time of onset. METHODS--All CPAs that occurred during a 9-month period and met entry criteria were included for study. The day was divided into 4-hour intervals and analyses were performed for evidence of periodicity in time of onset. The CPAs were then divided into those that were "expected" and those that were "unexpected," and further analyses of periodicity were performed. RESULTS--For the total study population (137 patients), a primary peak frequency of CPA occurred during the interval from 4 to 7:59 AM, and a secondary peak frequency occurred during the 8 to 11:59 PM interval. A minimum frequency occurred during the midnight to 3:59 AM interval. The onset of unexpected CPA peaked during the 4 to 7:59 AM interval, and expected CPA followed no circadian pattern. CONCLUSIONS--Our analysis of CPA occurring in patients hospitalized on the general medical ward demonstrated a circadian pattern of onset that favored the early-morning hours. This pattern is predominantly due to unexpected CPA. If further study confirms our observations, changes in the prophylaxis of in-hospital CPA and adjustments in staff responses to its occurrence may be indicated.  相似文献   
10.
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence.  相似文献   
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