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51.
Background: The functional role of the cavotricuspid isthmus (CTI) for common atrial flutter (cAFL) remains to be elucidated. In the present study, we examined whether the EnSite system (St. Jude Medical, St. Paul, MN, USA), a noncontact mapping system, is useful to evaluate the conduction properties of CTI to minimize radiofrequency (RF) ablation applications for cAFL. Methods: We enrolled 22 consecutive patients with cAFL (64.1 ± 9.5 years old, M/F 21/1) treated with the EnSite system and examined the conduction properties during cAFL and during atrial pacing. In addition, the effectiveness of the system was evaluated in comparison with the conventional ablation group (67 ± 8.9 years old, n = 15, M/F 13/2). Result: In 11 out of the 22 patients, CTI block line was achieved by fewer RF applications on a presumed single activation pathway which the EnSite system showed (point ablation [PA] group), and the remaining 11 patients needed additional linear ablation (additional ablation [AA] group). The number of RF applications in the PA group was significantly smaller than that in the conventional group. During the lower lateral right atrial pacing at a cycle length of 600 ms, the CV of the CTI in the PA group was smaller compared to that in the AA group (1.36 ± 0.61 vs 2.17 ± 0.66 m/s, P < 0.05), although the CV during cAFL (averaged cycle length 245 ± 34 ms) was not different in both groups. Conclusions: These results indicate that targeting the presumed single line identified by EnSite could be an optional therapy for cAFL RF ablation, and diverse conduction properties in CTI are related to the success rate of this procedure. (PACE 2012;35:1464–1471)  相似文献   
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Delayed cerebral vasospasms after subarachnoid hemorrhage (SAH) are a risk factor for poor prognosis after successful treatment of ruptured intracranial aneurysms. Different strategies to remove clots from the subarachnoid space and prevent vasospasms have different outcomes. Intrathecal urokinase infusion therapy combined with endovascular treatment (EVT) can reduce the incidence of symptomatic vasospasms. To analyze the relationship between symptomatic vasospasms and residual SAHs after urokinase infusion therapy, we retrospectively reviewed the records of 348 consecutive patients managed with EVT and intrathecal urokinase infusion therapy for aneurysmal SAH at our institution between 2010 and 2021. Among them, 163 patients met the study criteria and were classified into two groups according to the presence of residual SAH in the cisterns, Sylvian fissures, and frontal interhemispheric fissure. The incidence of symptomatic vasospasms and the clinical outcomes were assessed. In total, eight (5.0%) patients developed symptomatic vasospasms. Patients with symptomatic vasospasms had a significantly higher incidence of residual SAH in the Sylvian or frontal interhemispheric fissures than those without (P <.0001). No patient with SAHs resolved by urokinase infusion therapy developed symptomatic vasospasms. However, the two groups did not differ significantly in terms of modified Rankin scale scores at discharge. Treatment with intrathecal urokinase infusion after EVT for aneurysmal SAH can substantially reduce the risk of clinically evident vasospasms.  相似文献   
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Abstract— Pharmacokinetic parameters and bioavailability of a new cardiotonic agent, loprinone hydrochloride, in beagle dogs were determined by measuring plasma levels of loprinone after intravenous bolus and oral administration. The plasma half-life after intravenous administration of loprinone varied among individuals over the range 2·65–15·40 h. The bioavailability after oral administration of loprinone as a solution was 37·1%. Effects of enterohepatic circulation on the time-course of plasma levels after intravenous administration of the drug were also studied in bile-duct-cannulated beagle dogs. The amounts of loprinone and its glucuronide excreted in bile during 8 h after administration were 25·4 and 8·6% of the dose, respectively, indicating the possibility of enterohepatic circulation. The plasma half-life in bile-ductcannulated beagle dogs was 1·98 h. These results indicate that the variation in the half-life in beagle dogs resulted from enterohepatic circulation and that the true half-life is about 2 h. The relative bioavailability after oral administration of the drug as a powder in a capsule compared with a solution was 95·7%. In addition, the amounts of loprinone and its glucuronide excreted in bile, and the AUC of plasma level after infusion for 30 min into the portal vein in bile-duct-cannulated beagle dogs were similar to those after bolus intravenous administration. These results show that the low bioavailability reflects incomplete absorption.  相似文献   
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AIM: To evaluate the feasibility and usefulness of extraperitoneal laparoscopic retroperitoneal lymph node dissection (RPLND) in the supine position after chemotherapy for advanced testicular carcinoma. METHODS: Three patients with advanced testicular cancer underwent chemotherapy. Although serum markers were decreased compared with the normal range, residual masses requiring surgical resection were recognized by computed tomography scanning. We applied extraperitoneal laparoscopic RPLND. The patients were placed in the supine position and the first trocar was inserted two finger widths medial to the anterior iliac spine. The retroperitoneal space was dilated using a preperitoneal distention balloon. Two more ports were inserted into the retroperitoneal space and surgery proceeded thereafter. RESULTS: The residual tumors were completely resected by laparoscopy. The procedure required 250-310 min and the bleeding volume was below 50 mL. Although the histopathological findings consisted only of necrosis in all of the patients, one patient recurred at the same place. CONCLUSIONS: Extraperitoneal laparoscopic RPLND in the supine position for residual tumors after chemotherapy is technically feasible and useful in terms of postoperative recovery. With regard to cancer control, further evaluation should be necessary.  相似文献   
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Three-dimensional structure of a human calcitonin analog (abbreviated as hCTa) in which the amino acids of the wild type are replaced at positions 12, 16 and 19 by leucine residues and further at position 22 by a tyrosine residue was studied in TFE solution by 1H-NMR and distance geometry calculations. This analog has a 15-20 times activity as compared with the wild type. The amino acid replacements resulted in formation of an amphiphilic α-helix in the region between the residues 4-20. The overall three-dimensional structure is similar to that of the wild type. The conformational feature of hCTa with a hydrophobic face composed with a Met and four Leu residues may be related to its higher hypocalcemic potency.  相似文献   
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Ureteral obstruction secondary to endometriosis is relatively uncommon. We present a 43-year-old multiparous woman who suffered from periodic left loin pain in the terminal period of her menstruation. Excretory urogram demonstrated left hydronephrosis and hydroureter and obstruction of the lower left ureter just inferior to the left sacroiliac joint without urolithiasis. An enhanced computed tomography scan showed soft tissue density mass around the left ureter at the level of the stenosis. She underwent transperitoneal laparoscopic ureterolysis and adhesiotomy of the left ureter under the diagnosis of ureteral endometriosis. Because blueberry spots were clearly observed on the pelvic brim, the fibrous tissue surrounded the ureter was removed with peritoneal bleeding spots. Histological examination of the surrounding tissue confirmed the ectopic endometriosis. Even though retroperitoneoscopy is frequently used for ureteral lesion, transperitoneal laparoscopy has an advantage for resection of ectopic endometriosis surrounding the ureter.  相似文献   
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The testicular toxicities of two compound semiconductor materials,gallium arsenide (GaAs) and indium arsenide (InAs), and arsenicoxide (As2O3) were examined in rats by repetitive intratrachealinstillation of these substances in suspension twice a week,a total of 16 times. A single instillation dose was 7.7 mg/kgin the GaAs and the InAs groups and 1.3 mg/kg in the As2O3 group.A significant decrease in sperm count and significant increasein the proportion of morphologically abnormal sperm were foundin the epididymis in the GaAs group. Especially, abnormal spermwith a straight head increased markedly in this group. In theGaAs–treated rats, there was 40-fold increase in the degeneratinglate elongated spermatids at the postspermiation stages, stagesIX, XI, and XI. From these results, it is indicated that GaAsdisturbed the spermatid head transformation at the late spermiogenicphases and caused spermiation failure. InAs caused a sperm countdecrease in the epididymis, though its testicular toxicity wasrelatively weak compared with that of GaAs. As2O3, a probabledissolution arsenic product of GaAs and InAs in vivo, did notshow any testicular toxicities in this study. It seems likelythat, along with arsenics, gallium and indium play a role inthe testicular toxicities of GaAs and InAs.  相似文献   
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