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71.
BACKGROUND: The da Vinci Surgical Robotic System is being increasingly used to perform complex urological operations by minimally invasive techniques. Prior abdominal surgery associated with intra-abdominal adhesions may complicate robotic surgery. METHODS: We used a cohort of consecutive 49 patients undergoing a variety of robotic urological procedures at our institution to study the impact of prior abdominal operations on early perioperative complications. RESULTS: A total of 21/49 (43%) patients (Group A) had no history of prior abdominal surgery and the rest 28/49 (57%; Group B) had undergone prior abdominal surgery. The incidence of peritoneal adhesions was significantly higher in patients with prior abdominal surgery compared to the rest of the cohort, 54% versus 10% (P=0.002). The median operative time, estimated blood loss, postoperative drop in hemoglobin, time to hospital discharge, postoperative narcotic analgesic use and postoperative complication rate between group A and group B were not statistically different. The overall perioperative complication rate for the entire cohort was 14.3%, with 6-8% of complications occurring in each of the two groups (P=1.0). Comparative subset analysis of 28 patients in Group B, 15 (54%) and 13 (46%) with or without intra-abdominal adhesions did not reveal a significant difference in perioperative complication rates either. However, operative time was longer in patients with intra-abdominal adhesions compared to patients without, median of 590 (281-922) and 434 (153-723) min respectively, although not statistically significant (P=0.059). CONCLUSION: Our study demonstrates that robotic urological surgery can be performed in patients with prior abdominal surgery without increased perioperative complications.  相似文献   
72.
Presence of microcalcifications within the specimens frequently signifies a successful attempt of stereotactic vacuum-assisted breast biopsy (VABB) in obtaining a pathologic diagnosis of the breast microcalcifications. In this study, the authors aimed to assess and compare the accuracy and consistency of calcified or noncalcified specimens obtained from same sites of sampling on isolated microcalcifications without mass in diagnosing high-risk and malignant lesions. To the best of our knowledge, an individual case-based prospective comparison has not been reported.With the approval from institutional review board of our hospital (Chang Gung Memorial Hospital), the authors retrospectively reviewed all clinical cases of stereotactic VABBs on isolated breast microcalcifications without mass from our database. The authors included those having either surgery performed or had clinical follow-up of at least 3 years for analysis. All the obtained specimens with or without calcification were identified using specimen radiographs and separately submitted for pathologic evaluation. The concordance of diagnosis was assessed for both atypia and malignant lesions.A total of 390 stereotactic VABB procedures (1206 calcified and 1456 noncalcified specimens) were collected and reviewed. The consistent rates between calcified and noncalcified specimens were low for atypia and malignant microcalcifications (44.44% in flat epithelial atypia, 46.51% in atypical ductal hyperplasia, 55.73% in ductal carcinoma in situ, and 71.42% in invasive ductal carcinoma). The discordance in VABB diagnoses indicated that 41.33% of malignant lesions would be misdiagnosed by noncalcified specimens. Furthermore, calcified specimens showed higher diagnostic accuracy of breast cancer as compared with the noncalcified specimens (91.54 % versus 69.49%, respectively). The evaluation of both noncalcified specimens and calcified specimens did not show improvement of diagnostic accuracy as compared with evaluating calcified specimens alone (91.54% versus 91.54%, respectively).The high prevalence of diagnostic discordance between the calcified and noncalcified specimens indicated the higher value of calcified specimens in diagnosing atypia and malignant microcalcifications. Noncalcified specimens did not provide additional diagnostic benefit from this study. The separation of calcified and noncalcified specimens may facilitate more focused interpretation from pathologists among the large number of specimens.  相似文献   
73.
BACKGROUND: Double atrial potentials recorded in the coronary sinus are not an unusual phenomenon in patients with supraventricular tachyarrhythmias. They have been demonstrated to potentiate the occurrence of atrial tachyarrhythmias. METHODS: Two hundred and forty-eight patients were included for investigating the presence of double atrial potentials on the coronary sinus recordings during electrophysiologic study. Group 1 consisted of 136 patients with WPW syndrome and group 2 consisted of 112 patients with atrioventricular nodal reentrant tachycardia (AVNRT). Group 1 patients had a higher incidence of induced atrial fibrillation (AF) (27% vs. 15%, P = 0.045) than group 2 patients. In addition, the incidence of double atrial potentials was significantly higher in group 1 than in group 2 patients (14% vs. 2%, P = 0.001). In group 1, 19 patients with double atrial potentials had a significantly higher incidence of left lateral bypass tracts (79% vs. 39%, P = 0.001) and induced AF (47% vs. 22%, P = 0.01) than 117 patients without double atrial potentials. CONCLUSIONS: WPW syndrome, especially with a left lateral bypass tract, had a higher incidence of double atrial potentials and induced AF than AVNRT. WPW patients with double atrial potentials had a higher incidence of induced AF than those without double atrial potentials. These findings may contribute to understanding the mechanism of induced AF in WPW syndrome.  相似文献   
74.
Herbal interactions with nifedipine/felodipine through cytochrome P450 (CYP) 3A inhibition is significant in humans. Shengmai-San (SMS), a three-herbal formula of Chinese medicine, is commonly prescribed in Asia populations for cardiovascular disorders. This study aimed to elucidate the impact of SMS on nifedipine/felodipine treatment by the findings from rat pharmacokinetic study of nifedipine to the retrospective cohort study of patients with hypertension. The 3-week SMS treatment increased the systemic exposure to nifedipine by nearly two-fold and decreased nifedipine clearance by 39% in rats. Among the ingredients of SMS component herbs, schisandrin B, schisantherin A, and methylophiopogonanone A, inhibited the nifedipine oxidation (NFO) activities of rat hepatic and intestinal microsomes, as well as human CYP3A4. Methylophiopogonanone A was identified as a time-dependent inhibitor of CYP3A4. After 1:5 propensity score matching, 4,894 patients with nifedipine/felodipine use were analyzed. In patients receiving nifedipine/felodipine, the subgroup with concurrent SMS treatment had a higher incidence of headache (92.70 per 1,000 personyears) than the subgroup without SMS treatment (51.10 per 1,000 person-years). There was a positive association between headache incidence and cumulative doses of SMS (1–60 g SMS: hazard ratio (HR): 1.39; 95% confidence interval (CI): 1.11–1.74; >60 g SMS: HR: 1.97; 95% CI: 1.62–2.39; p < 0.0001). However, patients who had higher cumulative SMS doses had a lower risk of all-cause mortality (1–60 g SMS: HR: 0.67; 95% CI: 0.47–0.94; >60 g SMS: HR: 0.54; 95% CI: 0.37–0.79; p = 0.001). Results demonstrated increased rat plasma nifedipine levels after 3-week SMS treatment and increased headache incidence should be noted in nifedipine/felodipine-treated patients with prolonged SMS administration.  相似文献   
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76.
OBJECTIVE: To evaluate the accuracy of a rapid assay that wasdeveloped to detect Helicobacter pylori antigen in the stool,using the principle of immunochromatography, in the Chinese population. METHODS: Eligible patients without prior treatment of H.pylori were recruited. An in‐house rapid urease test (RUT) andhistology were used as the gold standard. The results of the rapidstool antigen test were compared with the gold standard. RESULTS: Valid rapid stool antigen test results for interpretationwere obtained from 94 consecutive patients (mean age: 52.5, range:22?82 years). Sensitivity, specificity, positive predictivevalue, negative predictive value and accuracy were, respectively, 77.5%,87.0%, 81.6%, 83.9% and 83.0%.The test was easy to perform and results were available within 15 min. CONCLUSION: The rapid stool antigen test using immunochromatography accuratelydiagnoses H. pylori infection in Chinese patients.  相似文献   
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80.
Background:One-lung anesthesia provides a better surgical field for thoracic procedures but also impairs the arterial oxygenation and venous admixture. During one-lung ventilation, pulmonary vasoconstriction is assumed to be present within both ventilated and collapsed lungs. We propose that arterial oxygenation could be optimized by offsetting the vasoconstriction within the microcirculation of ventilated lung. Method:In an anesthetized dog model, incremental doses of prostaglandin E1 (PGE1) were selectively infused into the main trunk of the pulmonary artery of the ventilated lung after one-lung ventilation for 60 min (PGE1 group, n=9). Arterial oxygenation and calculated venous admixture (Qs/Qt) was also assessed in a time-course control group (Control group, n =5). During two-lung ventilation (FIO2: 0.66), arterial PO2 and venous admixture was 44.22 ± 3.5 kPa and 10.7±2.3%, respectively. One-lung ventilation (FIO2: 0.66) with left lung collapsed reduced arterial PO2 to 11.6±1.7 kPa and increased venous admixture to 40.7±5.8% (P<0.001). Venous O2 tension also decreased from 6.3±0.7 kPa to 5.0±0.6 kPa with a slight increase in mean pulmonary artery pressure and pulmonary vascular resistance (P <0.05). Results: During selective infusion of PGE1 at a dose of 0.04 to 0.2 μg kg-1 min-1, there was a dose-dependent improvement in arterial PO2 with a parallel reduction of venous admixture during one-lung ventilation. Arterial PO2 increased to a maximum of 23.0±4.3 kPa, and the venous admixture decreased significantly to a minimum of 27.4±4.2% by PGE1 at a dose of 0.04-0.4 μg kg-1 min-1 (P<0.01). PGE1 resulted in a small increase in cardiac output and decreases of pulmonary pressure and pulmonary vascular resistance at a relatively high dose of 0.4 μg kg-1 min-1 during selective infusion (P<0.05). Conclusion: These results suggest that a selective pulmonary artery infusion of PGE1 to the ventilated lung within the dose range of 0.04-0.4 μg kg-1 min-1 is practical and effective to improve arterial oxygenation and reduce venous admixture during one-lung ventilation.  相似文献   
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