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排序方式: 共有846条查询结果,搜索用时 15 毫秒
831.
Dilek TU Gurbuz A Yazici G Arslan M Gulhan S Pata O Dilek S 《American journal of perinatology》2006,23(3):167-172
The objective of this study was to evaluate predictive value of cervical volume and length measurement for preterm delivery in low-risk pregnancies by transvaginal ultrasound. Two hundred fifty pregnant women were underwent ultrasound examination at 22 weeks of gestation by transvaginal route. Cervical length, width, and anteroposterior diameters were measured and cervical volume was calculated. All subjects were observed until term. Predictive values of cervical length and cervical volume were calculated and compared with predict preterm delivery. Preterm delivery occurred in 18 patients (7.2%). Mean cervical length and volume were statistically different between term and preterm delivered patients ( P = 0.001). Areas under curves were 0.913 for cervical volume and 0.923 for cervical length; this difference was not statistically significant ( P = 0.289). Sensitivity of cervical volume was 73.3% for 32-mL cut-off value with 12.85% false-positive rate and cervical length had 80% sensitivity at the 33.15-mm cut-off value with 12.7% false-positive rate. Cervical volume measurement by two-dimensional ultrasound did not add any benefit compared with the cervical length measurement for prediction of preterm delivery. 相似文献
832.
Retroperitoneal fibrosis (RF) is a clinical entity characterized by the progressive proliferation of connective tissue that rarely forms a mass involving the periaortic area of the abdomen, which may be idiopathic as well as a result of an inflammatory process after aneurysmal dilatation of the aorta. This fibrotic tissue may cover both aorta and iliac arteries, reach the retroperitoneum and surrounding ureters, and cause serious obstructions and renal insufficiency in three-quarters of patients. Most of the patients are known to have atherosclerosis and local inflammation against the antigens of the plaques. A systemic autoimmune disease presenting with retroperitoneal fibrosis seems to be pronounced more frequently nowadays because of the elevated acute-phase reactant levels, positive autoantibodies, and concurrent autoimmune diseases affecting other organs in majority of the diagnosed patients. Ultrasonography, computed tomography, magnetic resonance imaging, positron emission tomography, and retroperitoneal biopsy are useful in diagnosing and assessing the full extent of the disease. Surgical interventions such as ureterolysis and aneurysm repair are frequently performed, but medical therapy including steroids and immunosuppressants is often needed because of the inflammatory and chronic-relapsing nature of the disease. In this paper, we described two cases diagnosed with RF secondary to hemilaminectomy and hypothyroidism, and we summarized the literature related to RF. 相似文献
833.
Erbil Y Salmaslioğlu A Barbaros U Bozbora A Mete O Aral F Ozarmağan S 《Urologia internationalis》2008,80(1):31-36
Adrenal cysts are very rare lesions, usually asymptomatic or without characteristic symptoms. They are classified as pseudocysts, endothelial cysts, epithelial cysts or parasitic cysts. Although pseudocysts are reported to be the most common clinically recognized adrenal cysts in surgical series, endothelial cysts are more common in autopsy series. We studied 15 consecutive patients with adrenal cysts who underwent surgical resection at our institution from 1990 to 2005. Of 15 patients with adrenal cysts, 10 had pseudocysts, 3 epithelial cysts, 1 an endothelial cyst and 1 a parasitic cyst. In conclusion, a better understanding of cystic adrenal masses is necessary to recognize true adrenal cysts and differentiating them from adrenal carcinoma or adenoma by demonstrating the foci of cystic or degenerative changes. 相似文献
834.
835.
Osseous defects of the jaws following trauma, cysts, infection or congenital deformity may show poor osteogenesis and the affected area may never be completely filled with bone. It is widely accepted in guided tissue regeneration that physically halting soft connective tissue proliferation into bone allows bone regeneration. This concept is called the "osteopromotion principle." The purpose of the present study was to evaluate the effect of solvent-dehydrated cortical bone plates as a barrier to allow bone regeneration by assessing the osteopromotion principle. 30 patients (18 male, 12 female) with cystic lesions of the jaws were assigned to two different groups. The patients in Group A were treated by enucleation. In Group B, were treated by removal of the lesion and placing a solvent-dehydrated cortical bone plate on top of the cyst cavity to avoid ingrowth of connective tissue. Both groups were evaluated radiographically using spiral-computed tomography (CT) before surgery and 12 months postoperatively. In group B, all cystic cavities showed complete bone healing in 12 months. At the same period, invasion of the soft connective tissue were observed in the patients treated only by enuclation. This study demonstrates that solvent-dehydrated cortical bone plates can be used as a barrier in treatment of cyst cavities and they hinder ingrowth of connective tissues and promote successful bone healing. 相似文献
836.
Yesim Erbil Nese Ozbey Umut Barbaros Haluk Recai Unalp Artur Salmasl?oglu Sel?uk ?zarmagan 《World journal of surgery》2009,33(10):2099-2105
Background
It is not clear whether nonfunctional adrenal incidentaloma (NFA) increases the risk of atherosclerosis and metabolic syndrome or whether this type of adrenal tumor has been found more frequently in patients with cardiometabolic risk factors. We aimed to determine the effects of NFA on cardiometabolic risk factors and endothelial function and to compare the patients with a 1:1 cardiometabolic risk factor matched control group. 相似文献837.
The purpose of the present paper is to predict the grain size of steel during the hot-rolling process. The basis represents a macroscopic simulation system that can cope with temperatures, stresses and strains of steel in a complete continuous rolling mill, including reversible pre-rolling and finishing rolling with several tenths of rolling passes. The grain size models, newly introduced in the present paper, are one-way coupled to the macro-scale calculations performed with the slice model assumption. Macroscale solution is based on a novel radial basis function collocation method. This numerical method is truly meshless by involving the space discretization in arbitrarily distributed nodes without meshing. A new efficient node generation algorithm is implemented in the present paper and demonstrated for irregular domains of the slice as they appear in different rolling passes. Multiple grain size prediction models are considered. Grain size prediction models are based on empirical relations. Austenite grain size at each rolling pass as well as the ferrite grain size at the end of rolling are predicted in this simulation. It is also shown that based on the rolling schedule, it is highly likely that recrystallization takes place at each pass throughout a continuous rolling mill. The simulation system is coded as a user-friendly computer application for industrial use based on programming language C# and an open source developer platform NET and runs on regular personal computers the computational time for a typical rolling simulation is usually less than one hour and can thus be straightforwardly used to optimize the rolling mill design in a reasonable time. 相似文献
838.
Xu F Finley TD Turkaydin M Sung Y Gurkan UA Yavuz AS Guldiken RO Demirci U 《Biomaterials》2011,32(31):7847-7855
Microscale hydrogels find widespread applications in medicine and biology, e.g., as building blocks for tissue engineering and regenerative medicine. In these applications, these microgels are assembled to fabricate large complex 3D constructs. The success of this approach requires non-destructive and high throughput assembly of the microgels. Although various assembly methods have been developed based on modifying interfaces, and using microfluidics, so far, none of the available assembly technologies have shown the ability to assemble microgels using non-invasive fields rapidly within seconds in an efficient way. Acoustics has been widely used in biomedical arena to manipulate droplets, cells and biomolecules. In this study, we developed a simple, non-invasive acoustic assembler for cell-encapsulating microgels with maintained cell viability (>93%). We assessed the assembler for both microbeads (with diameter of 50?μm and 100?μm) and microgels of different sizes and shapes (e.g., cubes, lock-and-key shapes, tetris, saw) in microdroplets (with volume of 10?μL, 20?μL, 40?μL, 80?μL). The microgels were assembled in seconds in a non-invasive manner. These results indicate that the developed acoustic approach could become an enabling biotechnology tool for tissue engineering, regenerative medicine, pharmacology studies and high throughput screening applications. 相似文献
839.
840.
Sanal FA Güler AU Inan U Ozdemır OS 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2011,23(2):89-95
In this case report, an alternative approach was presented for treatment of coronal fracture including pulp of maxillary central incisor, one of the abutments of an adhesive bridge, by using fiber post and tooth's own fractured component. The patient was referred to our clinic with the complaint of pain from the upper right central incisor and mobility of the adhesive bridge in maxillary anterior segment. It was realized that, the upper right central incisor, one of the abutments of the adhesive bridge, had been fractured at middle thirds of the crown including the pulp chamber. After dismounting the adhesive bridge and completion of the root canal treatment, a fiber post was placed into the fractured tooth. The fractured component, adherent to adhesive bridge retainer, was concorded to the fiber post. The whole structure was cemented with adhesive resin. A 1-mm-wide groove was made along the fracture line and restored with composite resin. The patient was evaluated clinically and radiographically at 12 and 30 months after the treatment. CLINICAL SIGNIFICANCE: Adhesive cementation of fractured component by supporting the remaining tooth structure with a fiber post is an inexpensive and conservative treatment alternative when the fractured component is compatible with the remaining tooth structure in cases of tooth fractures including the pulp chamber at anterior segment. 相似文献