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11.
Ulug U Jozwiak EA Mesut A Berksoy MM Bahceci M 《Human reproduction (Oxford, England)》2004,19(2):360-364
BACKGROUND: The purpose of this study was to determine the rate of spontaneous gestational sac loss during the first trimester in women achieving multiple pregnancies by ICSI. METHODS: A retrospective analysis was performed of 1448 consecutive multiple pregnancies conceived by ICSI. RESULTS: Of the cohort of 1448 pregnancies, twin gestations constituted 59.6% (864), triplets 30.2% (438) and quadruplets 10.0% (146). During the first trimester, 69 (4.7%) patients miscarried, while 179 (12.3%) continued their pregnancies and had fewer gestational sacs at the end of the first trimester than at the beginning. The overall loss rate of any gestational sac during the first trimester in these multiple pregnancies was 10.1%. There was a significant difference in the frequency of spontaneous reduction to twin or singleton pregnancies in the first trimester between women carrying triplets (11.7%) and those carrying quadruplets (3.5%) [P = 0.004; odds ratio (OR) 3.5; 95% confidence interval (CI) 1.3-9.1]. The frequency of gestational sac loss was significantly greater among women >35 years old (20.9%) than in women less than 35 years old (15.9%) (P = 0.03; OR 1.4; 95% CI 1.0-1.9). CONCLUSION: In multiple pregnancies there is a significant risk of spontaneous loss of any embryo during the first trimester. These findings should be considered prior to any decision about selective embryo reduction. 相似文献
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Sahin M 《Annals of biomedical engineering》2004,32(6):823-830
Recording the motor output of the central nervous system from the cervical spinal cord was investigated as a method of generating voluntary command signals, potentially to be used in quadriplegic individuals. Corticospinal volleys evoked by motor cortex stimulation were recorded from the spinal cord surface with multicontact electrodes in anesthetized cats. The multicontact recordings were analyzed for their information-carrying capacity as a neural interface. Neural signals resulting from the stimulation of various points in the motor cortex were considered as symbols of an alphabet that were sent through a discrete information channel. The information capacity of this channel at the thermal noise level of the electrode contacts was calculated. The maximum information rate was 1.57 bits in a trial for a 4-symbol alphabet. The background noise that reduces the information rate to 50% of its maximum theoretical value was defined as the half-bitrate-noise-tolerance (HBR-NoiseTol) and used as a measure of symbol distinguishability. The HBR-NoiseTol for all trials on average was 24 +/- 12%, 18 +/- 10%, and 15 +/- 9% for interfaces with 2-, 3-, and 4-symbol alphabets (n = 11 trials). The average peak-to-peak amplitude of the neural volleys was 13.5 +/- 6.7 microV (n = 11). These results suggest that the corticospinal signals can be recorded with spatial selectivity from the spinal cord surface and thus warrant further investigation of their potential use for a spinal cord-computer interface. 相似文献
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Orkun Koban Ahmet Öğrenci Ezgi Ayçiçek Akar Ahmet Sadık Uyanık Mesut Yılmaz Sedat Dalbayrak 《Journal of orthopaedic science》2021,26(3):369-374
BackgroundIt is extremely difficult to treat spine disorders with stabilization in patients with rheumatoid arthritis. Because revision rates are significantly higher in rigid stabilization. To date, there is no data about patients with rheumatoid arthritis treated with dynamic stabilization. Our aim was to compare the radiological and clinical results of patients with rheumatoid arthritis who underwent lumbar rigid stabilization or dynamic stabilization with Polyetheretherketone rod (PEEK).MethodsPatients with degenerative lumbar spine disease with rheumatoid arthritis who underwent dynamic stabilization between 2013 and 2015 and rigid stabilization between 2010 and 2012 were evaluated radiologically for adjacent segment disease, proximal junctional kyphosis, system problem (nonunion, screw loosening, instrumentation failure, pull out). It was also compared according to both the revision rates and the Visual Analog Scale and Oswestry Disability Index scores at the 12th month and 24th month.ResultsThe difference of decrease in Visual Analog Scale and Oswestry Disability Index scores from preoperative to 12th month between patients who underwent dynamic stabilization and rigid stabilization was statistically insignificant. However, there was a significant difference of increase in Visual Analog Scale and Oswestry Disability Index scores between the 12th month and 24th month of patients who underwent rigid stabilization, compared with patients with dynamic stabilization. In patients with dynamic stabilization, the problems of instrumentation were seen less frequently. Revision rates were high in patients with rigid stabilization when compared the patients with dynamic stabilization.ConclusionRadiological and clinical outcomes in patients with rheumatoid arthritis operated with dynamic stabilization are more significant when compared to rigid stabilization. These patients have lower pain and disability scores in their follow up periods. Revision rates are lower in patients with dynamic stabilization. 相似文献
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Güven Lüleci Meral Sakizli Altan Günalp Ilhan Erkan Dogan Remzi 《Journal of surgical oncology》1981,16(4):327-331
In the blood samples obtained from a total of 68 patients with cancers of the urinary bladder, prostate, and cervix, who applied to the Departments of Urology, Obstetrics, and Gynecology of Hacettepe Medical Faculty, neutralizing antibodies were sought for against herpes simplex type 2 by neutralization test. The same test was applied to 35 control patients with no known malignancies. In contrast to the presence of the antibody in 62.86% of the control subjects, this ratio was 90.70% in patients with cancer of the urinary bladder, 87.50% in those with prostatic carcinoma, and 88.89% in those with cancer of the cervix. 相似文献
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The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report 总被引:1,自引:1,他引:0
Arslan N Ozturk E Ilgan S Narin Y Dundar S Tufan T Pekcan M Bayhan H 《Annals of nuclear medicine》2000,14(1):39-46
The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI. 相似文献
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?zgür Akgül Erdin? ?etinkaya ?iyar Ers?z Mesut Tez 《World journal of gastroenterology : WJG》2014,20(20):6113-6122
Colorectal carcinoma (CRC) is the third most common cancer, and approximately 35%-55% of patients with CRC will develop hepatic metastases during the course of their disease. Surgical resection represents the only chance of long-term survival. The goal of surgery should be to resect all metastases with negative histological margins while preserving sufficient functional hepatic parenchyma. Although resection remains the only chance of long-term survival, management strategies should be tailored for each case. For patients with extensive metastatic disease who would otherwise be unresectable, the combination of advances in medical therapy, such as systemic chemotherapy (CTX), and the improvement in surgical techniques for metastatic disease, have enhanced prognosis with prolongation of the median survival rate and cure. The use of portal vein embolization and preoperative CTX may also increase the number of patients suitable for surgical treatment. Despite current treatment options, many patients still experience a recurrence after hepatic resection. More active systemic CTX agents are being used increasingly as adjuvant therapy either before or after surgery. Local tumor ablative therapies, such as microwave coagulation therapy and radiofrequency ablation therapy, should be considered as an adjunct to hepatic resection, in which resection cannot deal with all of the tumor lesions. Formulation of an individualized plan, which combines surgery with systemic CTX, is a necessary task of the multidisciplinary team. The aim of this paper is to discuss different approaches for patients that are treated due to CRC liver metastasis. 相似文献