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1.
Mucin histochemistry was performed on the squamocolumnar junction (Z-line) of the gastroesophageal region of 49 autopsied previable fetuses, stillbirths, infants, and young children, using alcian blue pH 2.5/periodic acid-Schiff (PAS) and alcian blue pH 1.0/PAS stains. Sialylated and neutral mucins were present in most and sulfated mucin in many cases. In only one fetus was a heterotopic focus of goblet cells found in the distal esophagus. This study confirms that the presence of acidic mucins in columnar epithelium, without goblet cells, at the Z-line and adjacent cardia is common in this age group. Undue reliance on mucin stains to identify metaplastic columnar epithelium, in the absence of goblet cells, may result in overdiagnosis of Barrett's esophagus in children.  相似文献   

2.
The experimental work discussed here supports the hypothesis that in the pathogenesis of MG the initial and essential steps take place within the thymus. Most if not all thymuses of MG patients contain B cells capable of producing AChR specific autoantibody along with appropriate stroma elements. Hyperplastic thymuses characteristically contain germinal centers with cellular complexes of AChR-producing MC and surrounding interdigitating dendritic cells. In thymomas, the source of the myasthenogenic autoantigen is less obvious. There are data suggesting that thymoma epithelium expresses a protein sharing certain peptide epitopes with the AChR alpha chain, although there is no further molecular similarity. A unique type of 'molecular self-mimicry' cold be involved in the initiation of thymoma-associated MG.  相似文献   

3.
OBJECTIVE: The utility of endoscopy in the management of patients with symptoms of gastroesophageal reflux disease (GERD) is unclear. The purpose of this prospective study was to assess the impact of endoscopy on the subsequent management of patients with uncomplicated reflux symptoms. METHODS: A total of 742 patients underwent endoscopy for symptoms of GERD. Endoscopists recorded the therapy before endoscopy, the findings of endoscopy, and the treatment recommendations after endoscopy. RESULTS: There was no difference in pre-endoscopy therapy or grade of esophagitis in subjects undergoing endoscopy for failed therapy versus GERD symptoms alone. After endoscopy, the most common strategy for patients taking omeprazole was to maintain or increase the dose. For those taking an H2 blocker before endoscopy, the most common outcome was to switch the patient to omeprazole, independent of the grade of esophagitis. CONCLUSIONS: Most patients undergoing endoscopy for symptoms of GERD were switched to omeprazole regardless of the endoscopic findings. No esophageal cancer was identified and the incidence of Barrett's esophagus was low. It appears that endoscopy itself did not change the management of patients receiving H2-blocker therapy. A trial of a proton pump inhibitor before endoscopy should be considered.  相似文献   

4.
5.
A prospective randomized study was conducted at the Family Planning Association of Hong Kong to compare the efficacy of the Yuzpe regimen and levonorgestrel (0.75 mg for two doses 12 h apart) in post-coital contraception. A total of 424 subjects were recruited into the Yuzpe group and 410 subjects into the levonorgestrel group; 77 subjects in the Yuzpe group and 79 subjects in the levonorgestrel group had further acts of intercourse during the treatment cycle. Fifteen pregnancies (3.5%) occurred in the Yuzpe group and 12 pregnancies (2.9%) in the levonorgestrel group. After excluding the patients who had further acts of intercourse, the failure rates in the Yuzpe group and the levonorgestrel group were 2.6 and 2.4% respectively. The incidence of nausea, vomiting and fatigue in the Yuzpe group was significantly higher than those in the levonorgestrel group. We conclude that levonorgestrel is an effective drug for post-coital contraception with a lower incidence of side-effects than the Yuzpe regimen.  相似文献   

6.
Blind deep venous puncture is an invasive procedure with risks of serious complications compromising the availability of veins for future punctures or endangering the patient's life. We designed a new hand-held pulsed Doppler probe for coaxial guidance of the puncture needle and a dedicated pulsed Doppler device displaying the depth of the measurement volume. We used this technique prospectively in two independent centers (the nephrology department and the intensive care unit) involving senior as well as junior staff members. Either the non-Doppler or the Doppler method were randomly selected for subclavian vein catheterization in 100 patients and for internal jugular vein catheterization in 30 patients. The success rate on the first attempt was 86.2% for the non-Doppler method versus 96.8% for the Doppler method (p = 0.03). The failure rate of the non-Doppler method used by junior staff members was 9.2%, reduced to 1.5% (p = 0.05) by secondary use of the Doppler method and/or help from a senior staff member (rescue procedure). Pulsed Doppler guidance reduced significantly the failure rate of venous punctures especially when used by seniors or by juniors after a training period.  相似文献   

7.
One hundred symptomatic patients were evaluated independently with upper gastrointestinal radiography and fiberoptic endoscopy, and the results were compared. Of the two endoscopists sequentially examining the same patient, one was informed of available clinical and radiographic details and the other was not. Knowledge of the x-ray examination by the informed endoscopist did not improve his accuracy. Each endoscopist made four errors of interpretation. The endoscopic and x-ray findings agreed in 46 of the 100 patients, most often (68%) in esophagus, least often (29%) in the stomach and half the time (45%) in the duodenum. Ulcer craters seen endoscopically were detected radiographically in 36% of patients. We conclude that: 1) knowledge of results of prior upper gastrointestinal radiography did not alter endoscopic results; 2) experienced endoscopists are accurate but make mistakes; and 3) endoscopic findings would have been unaltered had radiography not been performed.  相似文献   

8.
E.coli bacteria, grown in anaerobic conditions, in the medium with glucose, lactose or maltose, upon transferring into a fresh medium with the same sugar acidify it and accumulate potassium ions with a fixed stoichiometry for the N,N'-dicyclohexylcarbodiimide-inhibited cation fluxes, which is equal to 2H+ of the cytoplasm per one K+ of the medium. Such an H(+)-K(+)-exchange is sensitive to osmotic shock. In the medium with lactose or maltose cation fluxes are less and the intracellular K+ activity at the moment of maximal accumulation is lower. The H(+)-K(+)-exchange with a variable stoichiometry of cation fluxes is lost in bacteria, grown in a medium with lactose or maltose.  相似文献   

9.
10.
PURPOSE: To compare prospectively the accuracy of spiral computed tomography (CT) with that of ventilation-perfusion scintigraphy for diagnosing pulmonary embolism. MATERIALS AND METHODS: Within 48 hours of presentation, 142 patients suspected of having pulmonary embolism underwent spiral CT, scintigraphy, and (when indicated) pulmonary angiography. Pulmonary angiography was attempted if interpretations of spiral CT scans and of scintigrams were discordant or indeterminate and intermediate-probability, respectively. RESULTS: In the 139 patients who completed the study, interpretations of spiral CT scans and of scintigrams were concordant in 103 patients (29 with embolism, 74 without). In 20 patients, intermediate-probability scintigrams were interpreted (six with embolism at angiography, 14 without); diagnosis with spiral CT was correct in 16. Interpretations of spiral CT scans and those of scintigrams were discordant in 12 cases; diagnosis with spiral CT was correct in 11 cases and that with scintigraphy was correct in one. Spiral CT and scintigraphic scans of four patients with embolism did not show embolism. Sensitivities, specificities, and kappa values with spiral CT and scintigraphy were 87%, 95%, and 0.85 and 65%, 94%, and 0.61, respectively. CONCLUSION: In cases of pulmonary embolism, sensitivity of spiral CT is greater than that of scintigraphy. Interobserver agreement is better with spiral CT.  相似文献   

11.
BACKGROUND: Multiprogrammable antiarrhythmia devices can treat monomorphic ventricular tachycardia (VT) with autodecremental overdrive pacing and/or with low-energy cardioversion. These two methods provide the opportunity to decrease patient discomfort typically experienced with high-energy pulses. Although both therapies are known to be effective, controversy persists over their relative safety and efficacy. METHODS AND RESULTS: The purpose of this study was to examine the safety and efficacy of autodecremental overdrive pacing and low-energy cardioversion in reproducibly terminating monomorphic VT in 24 patients with multiprogrammable antiarrhythmia devices. The protocol required that identical ECG morphology VT be reproducibly induced four times to assess the outcome of antitachycardia pacing and cardioversion twice for each patient in a randomized fashion. Each episode of VT was induced via the implanted device. Autodecremental overdrive pacing initially began with seven stimuli at 97% of the VT cycle length, decrementing by 10 msec per stimulus to a minimum coupling interval of 200 msec. If ineffective, autodecremental overdrive pacing was allowed to iterate three more times for a total of four pacing interventions. With each iteration, one stimulus was added to the pacing train. Similarly, with low-energy cardioversion, up to four therapeutic attempts were made, beginning with a 0.2-J pulse. If ineffective, pulse energy was increased to 0.4, 1.0, and finally 2.0 J. All interventions were automatic without human interference. VT (cycle length, 306 +/- 42 msec) was repeatedly terminated in 15 of 24 patients (63%) by autodecremental overdrive pacing and in 18 of 24 patients (75%) by low-energy cardioversion (p = 0.53). Eight of the 24 patients (33%) had their VT terminated repeatedly by both therapies. VT accelerated to faster VT or ventricular fibrillation by autodecremental overdrive pacing in four of 24 patients (17%) and by low-energy cardioversion in five of 24 (21%) (p = 0.88). Only one of the 24 patients (4%) accelerated with both therapies. No patient was unaffected by either therapy. CONCLUSIONS: In the manner programmed, autodecremental overdrive pacing and low-energy cardioversion have similar efficacy and acceleration rates. Response to one therapy does not predict response to the other.  相似文献   

12.
OBJECTIVE: The purpose of this study was to compare dual-phase helical CT and endosonography for the diagnosis and staging of pancreatic tumors. SUBJECTS AND METHODS: Thirty patients with suspected pancreatic tumors underwent endosonography and dual-phase helical CT. A pathologic diagnosis was obtained in all cases with surgery (n = 23) or biopsy (n = 7), resulting in 27 neoplasms. Dual-phase helical CT and endosonographic findings were correlated with surgical and pathologic findings to determine diagnosis and resectability of pancreatic tumors. RESULTS: Overall diagnostic sensitivity was 92% for dual-phase helical CT and 100% for endosonography (p = .45). Overall accuracy for staging of pancreatic tumors was 93% for both dual-phase helical CT and endosonography. Overall accuracy for predicting resectability was 90% for both dual-phase helical CT and endosonography. Accuracy of predicting unresectability was 100% for dual-phase helical CT and 86% for endosonography (p > .80). Differences were not considered statistically significant. CONCLUSION: Dual-phase helical CT and endoscopic sonography do not differ significantly for diagnosis and assessment of resectability of pancreatic tumors.  相似文献   

13.
This retrospective study reports our experience managing 78 patients with adenocarcinoma of the esophagus and gastroesophageal junction operated between January 1982 and December 1996. Altogether 18 patients presented with stage I and II disease, and 60 patients had stage III and IV disease at presentation; 56 patients (71.8%) were found to have resectable disease. Of these, transhiatal esophagectomy was possible in 51 patients. Transthoracic esophagectomy was done in 3 patients, and a left thoracoabdominal approach was used in 2 patients. The stomach was used as conduit in 50 patients and the colon in 6 patients. Twenty-two patients were found to have unresectable lesions at laparotomy and underwent various palliative procedures. Overall operative mortality was 6.3%. Mortality in the resectable group was only 3.6%. Follow-up ranges from 3 to 128 months, with four patients lost to follow-up at 1, 6, 8, and 10 months. The 5-year survival of the whole group according to Kaplan and Meier survival analysis was 21.27% with a median survival of 13.48 months. Univariate analysis using the log-rank test revealed stage of the disease and resectability to be significant predictors of survival. On multivariate analysis, curative resection appeared to be the most significant predictor of survival in patients undergoing resection.  相似文献   

14.
OBJECTIVE: Our objective was to compare intravascular sonography with digital subtraction angiography (DSA) in the assessment of luminal dimension and morphologic features of endovascular stents and stent grafts. MATERIALS AND METHODS: Thirty-seven pelvic and 24 femoral stents (12 Wall-stents; 27 covered and 22 uncovered nitinol stents) in 50 patients were evaluated 15 +/- 10 months after implantation by DSA and intravascular sonography. The degree of maximum instent restenosis as revealed by DSA and intravascular sonography was compared for each location. Morphologic features of the stents and stenoses were also assessed. RESULTS: Intravascular sonography and DSA correlated well (R2 = .96) in determining in-stent restenosis. In-stent restenosis was underestimated by 13% +/- 6% by DSA compared with intravascular sonography. Differences in determining in-stent restenosis with intravascular sonography and DSA were not associated with severity of stenosis or type of stent. Intravascular sonography revealed incomplete expansion of stents in 21 cases, whereas DSA revealed incomplete expansion of stents in seven cases. The intra- and interobserver variabilities in our study were 4% and 5%, respectively. CONCLUSION: In-stent restenoses are underestimated with DSA. Intravascular sonography is superior to DSA for detection of incomplete stent expansion.  相似文献   

15.
The combined effects of pressure and temperature on the activity of butyrylcholinesterase (BuChE) were investigated in the pressure range from 10(-3) to 5 kbar and temperature range from -10 degrees C to 70 degrees C. Inactivation of the enzyme showed a complex dependence on pressure and temperature. Under moderate pressures (1-3 kbar) at temperatures 40-65 degrees C BuChE was resistant to heat inactivation; under other conditions of pressure and temperature, the action of both parameters was synergistic and caused inactivation. Results allowed to construct a pressure-temperature kinetic phase diagram for the enzyme inactivation. The elliptic diagram for the irreversible transition active-->inactive BuChE as a function of both pressure and temperature has a positive angular coefficient. This indicates that pressure acts as a stabilizer of BuChE against heat denaturation.  相似文献   

16.
Spinal muscular atrophy (SMA) is a frequent autosomal recessive neurodegenerative disorder leading to weakness and atrophy of voluntary muscles. The survival motor neuron gene (SMN) is a strong candidate for SMA and present in two highly homologous copies (telSMN and cenSMN) within the SMA region (5q11.2-q13.3). More than 90% of SMA patients show homozygous deletions of at least exon 7 of telSMN, whereas absence of cenSMN seems to have no clinical consequences. In 23 non-deleted SMA patients, we searched for intragenic mutations of the SMN genes in exons 1-7 and the promotor region by single strand conformation analysis. We identified two different missense mutations, S2621 and T2741, in exon 6 of telSMN in three independent SMA families, providing further evidence for the telSMN gene as a SMA determining gene. Both mutations, as well as two previously described mutations (Y272C and G279V) are located within a highly conserved interval from codon 258 to codon 279 which seems to be an important functional domain of the telSMN protein. Recently, this region has been shown to contain a tyrosine/glycine-rich motif, which is also present in various RNA binding proteins, suggesting a potential role of SMN in RNA metabolism. Missense mutations might be useful for in vivo and transgenic experiments and further investigations on understanding the function of the telSMN protein.  相似文献   

17.
OBJECTIVES: Evaluate cartilaginous healing in rabbits in response to surgically created thyroid cartilage fractures. Compare healing between laryngeal fracture repair techniques. STUDY DESIGN: Animal model. MATERIALS AND METHODS: Laryngectomy specimens were analyzed at 10 weeks, following paired wire fixation (n = 7) and miniplate fixation (n = 7) of thyroid cartilage fractures. RESULTS: Cartilaginous unions were present in all seven of the miniplated repairs, while fibrous unions were present in six of the wired repairs. The measure of distraction at the fracture site was significantly greater in the wired repairs compared with the plated repairs (P = .005). Furthermore, in five of seven miniplated repairs no distraction at the healed fracture site was present. CONCLUSIONS: The results demonstrate the ease, tolerability, and superiority of the miniplate fixation technique for the thyroid cartilage fractures, based on a rabbit model.  相似文献   

18.
BACKGROUND: The high proportion of gastric carcinomas present in an unresectable stage, together with the emergence of multimodal treatments, increases the usefulness of objective staging methods that avoid unnecessary laparotomies. METHODS: A prospective evaluation of the accuracy of laparoscopy in the staging of 71 patients with gastric adenocarcinoma is presented. Serosal infiltration, retroperitoneal fixation, metastasis to lymph nodes, peritoneal and liver metastasis, and ascites were determined in the staging workup. Sensitivity, specificity, and predictive values were calculated and compared with those obtained with ultrasonography (US) and computed tomography (CT). RESULTS: The diagnostic accuracy of laparoscopy in the determination of resectability was 98.6%. Consequently, over 40% of patients were spared unnecessary laparotomies. Laparoscopy yielded diagnostic indices superior to US and CT for all the tumoral attributes studied. Our technique permits accurate assessment and pathologic verification of liver and the peritoneal and retroperitoneal extent of tumor invasion in the majority of patients. CONCLUSIONS: Laparoscopy in gastric adenocarcinoma is a reliable technique that provides accurate assessment of resectability and stage, thus avoiding unnecessary laparotomies in patients in whom surgical palliation is not indicated. A stepwise diagnostic workup combining imaging and minimally invasive techniques is proposed.  相似文献   

19.
A prospective study of the pharmacokinetics of itraconazole solution was performed in 11 patients who underwent allogeneic BMT (day of BMT = day 0) after a conditioning regimen including total body irradiation (TBI). Itraconazole solution (400 mg once a day) was given 7 days before BMT and continued up to the end of neutropenia unless another antifungal treatment was necessary. Blood samples were collected before itraconazole intake (Cmin) and 4 h later (Cmax) every other day for assays of itraconazole (ITRA) and its active metabolite hydroxy-itraconazole (OH-ITRA). The mean values of Cmin ITRA and OH-ITRA, respectively, were 287 +/- 109 ng/ml and 629 +/- 227 ng/ml at day -1 and 378 +/- 147 ng/ml and 725 +/- 242 ng/ml at day +1. The maximum Cmin values were observed at day +3. Six patients at day -1 (54%) and 8 at day +1 (72%) had satisfactory residual plasma concentrations of at least 250 ng/ml of unchanged ITRA. From day +1 to day +9, eight patients discontinued the itraconazole treatment, five of them had satisfactory plasma residual concentrations at this time. This work shows a good bioavailability of itraconazole oral solution during the early phase after allogeneic BMT, but more data are needed for the late phases.  相似文献   

20.
PURPOSE: We evaluated whether the grade assigned to the Achilles tendon's appearance on sonograms can be used to predict the outcome of achillodynia. METHODS: A retrospective evaluation was done of a case series of patients with Achilles tendon pain seen at a sports medicine clinic. The study consisted of chart reviews, telephone follow-up interviews, and grading of ultrasound images of the tendon obtained during the initial visit. The grading scheme was as follows: grade 1, normal tendon; grade 2, enlarged tendon; and grade 3, tendon containing a hypoechoic area, regardless of size. The time needed to recover from symptoms was compared between grades using survival analysis. RESULTS: The group consisted of 33 patients, with a mean age of 35.8 years and a mean follow-up time of 24.3 months. There was a statistically significant difference in the time to full recovery between grades (p = 0.02). Patients with grade 1 tendons had a prompter resolution of symptoms than did patients with grade 2 or 3 tendons. CONCLUSIONS: This retrospective study of the outcome of achillodynia demonstrates the possible use of tendon sonography as a prognostic tool to supplement physical examination.  相似文献   

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