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991.
992.
Seong Whi Cho Soon Gu Cho Jung Hee Lee Hyung-Jin Kim Myung Kwan Lim Jong Hwa Kim Chang Hae Suh 《Korean journal of radiology》2002,3(2):105-112
Objective
To explore the in-vivo 1H- MR spectral features of adnexal lesions and to characterize the spectral patterns of various pathologic entities.Materials and Methods
Thirty-one patients with surgically and histopathologically confirmed adnexal lesions underwent short echo-time STEAM (stimulated echo acquisition method) 1H- MR spectroscopy, and the results obtained were analysed.Results
The methylene present in fatty acid chains gave rise to a lipid peak of 1.3 ppm in the 1H- MR spectra of most malignant tumors and benign teratomas. This same peak was not observed, however, in the spectra of benign ovarian epithelial tumors: in a number of these, a peak of 5.2 ppm, due to the presence of the olefine group (-CH=CH-) was noted. The ratios of lipid peak at 1.3 ppm to water peak (lipid/water ratios) varied between disease groups, and in some benign teratomas was characteristically high.Conclusion
An intense lipid peak at 1.3 ppm is observed in malignant ovarian tumors but not in benign epithelial tumors. 1H- MRS may therefore be helpful in the differential diagnosis of adnexal lesions. 相似文献993.
Low-pressure laparoscopy may ameliorate intracranial hypertension and renal hypoperfusion 总被引:2,自引:0,他引:2
Rosin D Brasesco O Varela J Saber AA You S Rosenthal RJ Cohn SM 《Journal of laparoendoscopic & advanced surgical techniques. Part A》2002,12(1):15-19
BACKGROUND: Increased abdominal pressure is associated with elevations in the intracranial pressure (ICP) and impaired renal function. These adverse effects are potentially important in clinical situations such as severe abdominal trauma and laparoscopic donor nephrectomy. It was hypothesized that the secondary elevation of ICP leads to release of vasoconstrictors, which may affect renal function by decreasing the renal blood flow (RBF). We investigated the effect of laparoscopy on ICP and renal blood flow in a porcine model. MATERIALS AND METHODS: The abdominal pressure of swine (N = 5; 20-25 kg) was gradually increased from baseline to 5, 15, and 25 mm Hg by insufflation of nitrogen into the abdominal cavity. The ICP was measured using a Camino monitor, and RBF was simultaneously measured using a Transonic Doppler probe placed on the renal artery. Results were analyzed using repeated measures ANOVA and the paired t-test. RESULTS: No significant change from baseline was observed in ICP and RBF when the abdominal pressure was 5 mm Hg. However, both ICP and RBF were affected by increasing the abdominal pressure to 15 and 25 mm Hg (P = 0.035 and 0.04 for ICP and P = 0.074 and 0.034 for RBF, respectively). CONCLUSIONS: Low-pressure laparoscopy may reduce the adverse effects of pneumoperitoneum on ICP and RBF. It may be advisable to use low pressures in laparoscopic surgery, especially when changes in ICP or renal perfusion may have significant clinical implications. 相似文献
994.
995.
This study presents an application of linear programming discriminant analysis (LPDA) to classify and to predict the symptomatic status of HIV/AIDS patients. We applied LPDA as well as several traditional discriminant analysis methods to the AIDS Cost and Services Utilization Survey data set in order to demonstrate the use of LPDA to classify the symptomatic status of HIV/AIDS patients. The potential benefit of LPDA in terms of the classification accuracy was also analyzed. 相似文献
996.
Eun Seong Lee Min Jung Kwon Hyeok Lee Kun Na Jung Ju Kim 《European journal of pharmaceutical sciences》2006,29(5):435-441
This study investigated the suitability of microsphere formulations for extended protein delivery and complete protein release. These microspheres were prepared by a multi-emulsion method and prepared using a mixture of poly(lactide-co-glycolide) (PLGA), RG 502H (lactide:glycolide=50:50, M(W) 9300) and sucrose acetate isobutyrate (SAIB). SAIB embedded into the microspheres and mixed with PLGA, improved the efficiency of enzyme encapsulation. The in vitro release rate of lysozyme (Lys) from the microspheres was reduced due to the high viscosity of the added SAIB and less degradation of PLGA by SAIB. These properties enabled prolonged release of Lys for up to 2 months, characterized by a minimal initial burst of Lys and nearly zero-order protein release kinetics result from co-administration of sorbitan monooleate 80. When it is considered that degradation products of SAIB are inactive for labile proteins, SAIB may be regarded as a promising candidate for long-acting protein delivery. 相似文献
997.
We present a simple guidewire insertion technique and a new way of prepping for the procedure for readvancement of partially
retracted Hickman catheters with the aid of a stiff hydrophilic guidewire. 相似文献
998.
Acetic acid as a sclerosing agent for renal cysts: Comparison with ethanol in follow-up results 总被引:1,自引:0,他引:1
Seo TS Oh JH Yoon Y Lim JW Park SJ Chang SG Jeon YH 《Cardiovascular and interventional radiology》2000,23(3):177-181
Purpose: To compare follow-up results of sclerotherapy for renal cyst using 50% acetic acid with those using 99% ethanol as sclerosing
agents.
Methods: Eighty-one patients underwent sclerotherapy and 58 patients, 23 males, 35 females, aged 6–76 years, having a total of 60
cysts, were included in this study; the others were lost to follow-up. The renal cysts were diagnosed by sonography, computed
tomography (CT), or magnetic resonance imaging (MRI). Sclerotherapy was performed using 50% acetic acid for 32 cysts in 31
patients and 99% ethanol for 28 cysts in 27 patients. Under fluoroscopic guidance, cystic fluid was aspirated as completely
as possible. After instillation of a sclerosing agent corresponding to 11.7%–25% (4–100 ml) of the aspirated volume, the patient
changed position for 20 min and then the agent was removed. Patients were followed up by sonography for a period of 1–49 months.
The volume of the renal cyst after sclerotherapy was compared with that of the renal cyst calculated before sclerotherapy.
Medical records were reviewed to analyze complications.
Results: The mean volume after sclerotherapy of the 17 cysts followed for 3–4 months in the acetic acid group was 5.1% of the initial
volume, and for the 14 cysts in the ethanol group it was 10.2%. Complete regression during follow-up was shown in 21 cysts
(66%) in the acetic acid group; the mean volume of these cysts before the procedure was 245 ml. The mean volume of the nine
(32%) completely regressed cysts in the ethanol group was 184 ml. Mild flank pain, which occurred in three patients in each
group, was the only complication and resolved the next day.
Conclusion: Acetic acid was an effective and safe sclerosing agent for renal cysts, tending to induce faster and more complete regression
than ethanol. 相似文献
999.
So Y Chung JK Seong SC Sohn YJ Kang HS Lee DS Lee MC 《Nuclear medicine communications》2000,21(1):103-109
The aim of this study was to ascertain whether knee SPET can localize lesion sites in patients with internal derangements of the knee. We performed knee SPET as a pre-arthroscopic examination in 63 consecutive patients. SPET imaging was performed with a triple-headed SPET camera 4 h after the injection of 99Tcm-methylene diphosphonate. Arthroscopic diagnoses were as follows: 28 medial meniscus injuries, 24 lateral meniscus injuries, 31 anterior cruciate ligament (ACL) injuries, three posterior cruciate ligament injuries and one medial collateral ligament injury. Of 30 patients with crescent-shaped increased activity at the medial tibial plateau, 22 had medial meniscus injuries (positive predictive value: PPV 73%); of 17 patients with crescent-shaped activity at the lateral tibial plateau, 13 had lateral meniscus injuries (PPV 76%). Of 18 patients with increased activity at ACL attachment sites (primary sign), 17 had ACL injuries (PPV 94%). Of 27 patients with increased activity at bone impaction sites of ACL injury (secondary sign), 22 had ACL injuries (PPV 81%). Of 32 patients who had either a primary or secondary sign, 26 had ACL injuries (PPV 81%). We conclude that knee SPET is very useful in the management of internal derangements of the knee, particularly in determining the need for arthroscopy by localizing lesion sites. 相似文献
1000.
Somatic mutations of ERBB2 kinase domain in gastric, colorectal, and breast carcinomas. 总被引:4,自引:0,他引:4
Jong Woo Lee Young Hwa Soung Si Hyung Seo Su Young Kim Cho Hyun Park Young Pil Wang Kyeongmee Park Suk Woo Nam Won Sang Park Sang Ho Kim Jung Young Lee Nam Jin Yoo Sug Hyung Lee 《Clinical cancer research》2006,12(1):57-61
PURPOSE: Recent reports revealed that the kinase domain of the ERBB2 gene is somatically mutated in lung adenocarcinoma, suggesting the mutated ERBB2 gene as an oncogene in human cancers. However, because previous reports focused the mutational search of ERBB2 primarily on lung cancers, the data on ERBB2 mutations in other types of human cancers have been largely unknown. EXPERIMENTAL DESIGN: Here, we did a mutational analysis of the ERBB2 kinase domain by PCR single-strand conformational polymorphism assay in gastric, colorectal, and breast carcinoma tissues. RESULTS: We detected the ERBB2 kinase domain mutations in 9 of 180 gastric carcinomas (5.0%), in 3 of 104 colorectal carcinomas (2.9%), and in 4 of 94 breast carcinomas (4.3%). All of the detected ERBB2 mutations except for one in-frame deletion mutation were missense mutations. Of the 16 ERBB2 mutations detected, 4 affected Val777 in the exon 20 site, and 3 affected Leu755 in the exon 19 site. We simultaneously analyzed the somatic mutations of EGFR, K-RAS, PIK3CA, and BRAF genes in the 16 samples with ERBB2 mutations, and found that all of the 3 colorectal carcinoma samples with ERBB2 mutations harbored K-RAS mutations. CONCLUSION: This study showed that in addition to lung adenocarcinomas, ERBB2 kinase domain mutation occurs in other common human cancers such as gastric, breast, and colorectal cancers, and suggested that alterations of ERBB2-mediated signaling pathway by ERBB2 mutations alone or together with K-RAS mutations may contribute to the development of human cancers. 相似文献