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排序方式: 共有1683条查询结果,搜索用时 15 毫秒
1.
Tarik Zafer Nursal Bulent Erdogan Turgut Noyan Melih Cekinmez Betul Atalay Nevzat Bilgin 《Journal of clinical neuroscience》2007,14(4):344-348
OBJECTIVE: Gastric paresis in traumatic brain injury (TBI) hinders the effectiveness of enteral support in this patient group. In this study we have investigated the effect of metoclopramide on gastric emptying in TBI patients. METHOD: In this prospective, randomized, controlled, double-blind study, 19 TBI patients with Glasgow Coma Scale scores of 3-11 were included. In all patients, enteral nutrition was commenced with a nasogastric feeding tube within 48 hours of trauma. Patients were randomized into two groups. In the metoclopramide (M) group, 10 mg metoclopramide was delivered intravenously three times daily for 5 days. In the control (C) group, an equal volume of saline was administered. Besides demographics, gastric emptying according to a paracetamol absorption test at days 0 and 5, time to reach target nutritional requirements, gastric residues, intolerance to feeding, nutritional complications, and clinical outcomes were recorded for each patient. RESULTS: The gastric residue rates were 2.7+/-7.4 mL and 8.1+/-17.7 mL per 100 patient days for groups C and M respectively (p=0.408). Similarly, feeding intolerance and complication rates did not significantly differ between groups C and M, (respectively p=0.543 and 0.930). Gastric emptying parameters also were similar between the study groups. CONCLUSION: We were unable to document any advantage to using metoclopramide in TBI patients. Simple intragastric enteral feeding with close monitoring of the possible complications seems to be sufficient with acceptable morbidity rates. 相似文献
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The use of 3D surface fitting for robust polyp detection and classification in CT colonography 总被引:3,自引:0,他引:3
In this paper we describe the development of a computationally efficient computer-aided detection (CAD) algorithm based on the evaluation of the surface morphology that is employed for the detection of colonic polyps in computed tomography (CT) colonography. Initial polyp candidate voxels were detected using the surface normal intersection values. These candidate voxels were clustered using the normal direction, convexity test, region growing and Gaussian distribution. The local colonic surface was classified as polyp or fold using a feature normalized nearest neighborhood classifier. The main merit of this paper is the methodology applied to select the robust features derived from the colon surface that have a high discriminative power for polyp/fold classification. The devised polyp detection scheme entails a low computational overhead (typically takes 2.20 min per dataset) and shows 100% sensitivity for phantom polyps greater than 5 mm. It also shows 100% sensitivity for real polyps larger than 10 mm and 91.67% sensitivity for polyps between 5 to 10 mm with an average of 4.5 false positives per dataset. The experimental data indicates that the proposed CAD polyp detection scheme outperforms other techniques that identify the polyps using features that sample the colon surface curvature especially when applied to low-dose datasets. 相似文献
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Glenn Perrigo Lee Belvin Paul Quindry Tarik Kadir Julie Becker Christine van Look John Niewoehner Frederick S. vom Saal 《Behavior genetics》1993,23(6):525-531
Infanticide is a reproductive strategy found in many mammals, especially rodents. The proportion of male and female house mice (Mus domesticus) that are either infanticidal or noninfanticidal is strain specific and varies widely from stock to stock. Male house mice also show strain-specific variation in the behavioral mechanisms that inhibit infanticidal individuals from killing their own offspring. The adult offspring generated from reciprocally crossed CF-1 and Wild stock house mice were tested for their behavior toward newborn pups. In male CF-1xWild hybrids, the proportion of infanticidal and noninfanticidal males matched with their maternal phenotype, whereas female CF-1xWild hybrids exhibited a proportion of behaviors typical of the CF-1 phenotype, regardless of their mother's genotype. Our results suggest three conclusions: first, that infanticide is a highly labile and heritable behavior in both sexes; second, that there is a sex difference in the genetic substrate that regulates the inheritance of infanticidal behavior; and third, that selection pressures in male mice may operate independently on the mechanisms that promote spontaneous infanticidal behavior versus the mechanisms that inhibit infanticide. 相似文献
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OBJECTIVE: Autophagy is a form of physiological programmed cell death which is observable after hormonal withdrawal. In this study, the FM3A murine breast tumor cell line was treated with epirubicin alone and with medroxyprogesterone acetate (MPA) or tamoxifen, to determine if structural and kinetic signs of autophagy may also occur in an enhanced manner during epirubicin sensitization via hormonal agents. METHODS: One-week soft agar colony growth, 96-hour values of plating and pulse thymidine labeling and electron microscopical examinations were performed following treatment with MPA and tamoxifen alone or with epirubicin. RESULTS: Tamoxifen induced signs of autophagy, which was enhanced when it was combined with MPA. Epirubicin also induced autophagy of secretory granules, which coalesced to form an intracytoplasmic lumen. Combining MPA with epirubicin enhanced the formation of apoptotic blebs and chromatin fragmentation. When epirubicin was combined with tamoxifen, peculiar nuclear structures were formed. CONCLUSIONS: Hormonal agents may modulate anthracycline activity towards specific patterns in eliciting cell death, via autophagy and/or as yet unknown nucleolus-specific interactions. 相似文献
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Mert Kilic Bilgen Coskun Metin Vural Ahmet Musaoglu Tarik Esen Mevlana Derya Balbay 《Andrologia》2021,53(5):e14041
In this study, we evaluated the role of the Prostate Imaging–Reporting and Data System (PI-RADS) classification of multiparametric magnetic resonance imaging (mpMRI) to determine the likelihood of prostate cancer (PCa) in patients with haemospermia. Fifty-one patients presenting with haemospermia between 2018 and 2020 were included in this retrospective study. Forty-two of the patients (82.4%) were over 40 years, and the median prostate-specific antigen (PSA) level was 1.4 ng/ml. Fourteen of the patients (27.5%) had recurrent haemospermia. All patients underwent mpMRI, and assessments were classified according to PI-RADS v2. The mpMRI revealed PI-RADS one to four lesions in 10 (19.6%), 30 (58.8%), 6 (11.8%) and 5 (9.8%) patients respectively. One patient with PI-RADS 3 and five with PI-RADS 4 lesions underwent cognitive fusion prostate biopsy depending on MRI findings, and two patients with PI-RADS 4 lesions were diagnosed with PCa. Patients with haemospermia and risk factors, that is aged over 40 years, a high PSA level or familial history of PCa, need a more thorough evaluation with mpMRI. 相似文献
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Cary Jo R. Schlick Tarik K. Yuce Anthony D. Yang Michael F. McGee David J. Bentrem Karl Y. Bilimoria Ryan P. Merkow 《Surgery》2021,169(2):240-247
BackgroundGuidelines recommend extended chemoprophylaxis for venous thromboembolism in high-risk patients having operations for inflammatory bowel disease. Quantifying patients' risk of venous thromboembolism, however, remains challenging. We sought (1) to identify factors associated with postdischarge venous thromboembolism in patients undergoing colorectal resection for inflammatory bowel disease and (2) to develop a postdischarge venous thromboembolism risk calculator to guide prescribing of extended chemoprophylaxis.MethodsPatients who underwent an operation for inflammatory bowel disease from 2012 to 2018 were identified from the American College of Surgeons National Surgical Quality Improvement Program for colectomy and proctectomy procedure targeted modules. Postdischarge venous thromboembolism included pulmonary embolism or deep vein thrombosis diagnosed after discharge from the index hospitalization. Multivariable logistic regression estimated the association of patient/operative factors with postdischarge venous thromboembolism. A postdischarge venous thromboembolism risk calculator was subsequently constructed.ResultsOf 18,990 patients, 199 (1.1%) developed a postdischarge venous thromboembolism within the first 30 postoperative days. Preoperative factors associated with postdischarge venous thromboembolism included body mass index (1.9% with body mass index ≥35 vs 0.8% with body mass index 18.5–24.9; odds ratio 2.34 [95% confidence interval 1.49–3.67]), steroid use (1.3% vs 0.7%; odds ratio 1.91 [95% confidence interval 1.37–2.66]), and ulcerative colitis (1.5% vs 0.8% with Crohn’s disease; odds ratio 1.76 [95% confidence interval 1.32–2.34]). Minimally invasive surgery was associated with postdischarge venous thromboembolism (1.2% vs 0.9% with open; odds ratio 1.42 [95% confidence interval 1.05–1.92]), as was anastomotic leak (2.8% vs 1.0%; odds ratio 2.24 [95% confidence interval 1.31–3.83]) and ileus (2.1% vs 0.9%; odds ratio 2.60 [95% confidence interval 1.91–3.54]). The predicted probability of postdischarge venous thromboembolism ranged from 0.2% to 14.3% based on individual risk factors.ConclusionPreoperative, intraoperative, and postoperative factors are associated with postdischarge venous thromboembolism after an operation for inflammatory bowel disease. A postdischarge venous thromboembolism risk calculator was developed which can be used to tailor extended venous thromboembolism chemoprophylaxis by individual risk. 相似文献
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Polilactofate microspheres for Paclitaxel delivery to central nervous system malignancies. 总被引:1,自引:0,他引:1
Khan W Li Wenbin Dang Betty M Tyler Greg Troiano Tarik Tihan Henry Brem Kevin A Walter 《Clinical cancer research》2003,9(9):3441-3447
PURPOSE: The purpose of this study was to demonstrate that surgically implanted, controlled-release, biodegradable polilactofate microspheres (Paclimer) can be used safely to bypass the blood-brain barrier and deliver paclitaxel to malignant brain tumors. EXPERIMENTAL DESIGN: The rate of paclitaxel release from Paclimer microspheres submerged in PBS was measured in vitro by high-performance liquid chromatography. In vivo studies of Paclimer were performed as intracranial implants in Fischer 344 rats in the presence or absence of 9L gliosarcoma. Mantel-Cox statistics were used to assess the efficacy of Paclimer at extending survival of tumor-bearing animals compared with control implants. Paclimer implants tagged with [(3)H]paclitaxel were used to measure biodistribution of paclitaxel from the Paclimer implant. RESULTS: Paclimer released paclitaxel at a constant rate for up to 3 months in vitro. In vivo, Paclimer implants placed intracranially in rats released active drug for up to 30 days after implantation and doubled the median survival of rats bearing established 9L gliosarcomas (median survival of paclitaxel-treated animals = 35 days; median survival of control-treated animal = 16 days; P < 0.0001). Active drug was distributed throughout the rat brain based on liquid scintillation counting and TLC. Rats implanted with Paclimer demonstrated no overt signs of neurotoxicity and exhibited local cytopathological changes consistent with exposure to an antimicrotubule agent. CONCLUSIONS: Paclimer extends survival in a rodent model of glioma with minimal morbidity and optimal pharmacokinetics. 相似文献