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931.
932.
Chest pain, a frequent complaint during childhood, rarely originates from a cardiac pathology. Although it usually is idiopathic, it also could be associated with psychogenic, musculoskeletal, respiratory, and digestive disorders. This study aimed to investigate a possible relation between bone mineral density and chest pain in children. Bone mineral density and bone metabolism parameters were measured for 50 children with chest pain, and the findings were compared with those for 40 age- and sex-matched healthy children. Most of the cases (64%) were in the idiopathic group, and musculoskeletal chest pain was the second most frequent complaint (12%). Although bone mineral densities and osteocalcin levels did not differ significantly between the whole chest pain group and the control group, both were found to be lower in the musculoskeletal chest pain group than in other groups and the control group (p < 0.05). Musculoskeletal chest pain may be related to reduced bone mineral metabolism, and monitoring of risk factors is of particular importance.  相似文献   
933.
The Edwards MIRA bileaflet mechanical prosthesis, a heart valve not yet available in the United States, is designed with a unique hinge mechanism, curved leaflets, and thin titanium housing. We performed this study to investigate its clinical performance and postoperative hemodynamic results. We implanted 58 Edwards MIRA prostheses in 51 patients in the aortic (n = 18), mitral (n = 26), and aortic and mitral (n = 7) positions. Patients' ages ranged from 25 to 84 years (mean age, 53.7 +/- 13.6). Operative mortality was 2% (n = 1), and late mortality was 4% (n = 2). Thromboembolic events were observed in 2 patients (valve thrombosis in 1 and a cerebrovascular event in 1). There were no complications related to anticoagulation. No signs of valvular dysfunction or paravalvular leakage were observed. Peak transvalvular gradients of the aortic prostheses ranged from 24.25 +/- 5.32 mmHg for the 21-mm valve to 11 +/- 1.41 mmHg for the 25-mm valve. The effective orifice area ranged from 1.99 +/- 0.12 cm2 for the 21-mm valve to 2.44 +/- 0.17 cm2 for the 25-mm valve. The mean transvalvular gradients of the mitral prostheses ranged from 5.85 +/- 2.91 mmHg for the 27-mm valve to 4.5 +/- 0 mmHg for the 31-mm valve. The effective orifice area ranged from 2.31 +/- 0.03 cm2 for the 27-mm valve to 2.64 +/- 0.05 cm2 for the 33-mm valve. These preliminary data suggest good hemodynamic function and a low rate of valve-related complications in the use of the Edwards MIRA mechanical prosthesis.  相似文献   
934.
Post-translational protein modification,including phosphorylation,is generally quick and reversible,facilitating rapid biologic adjustments to altered cellular physiologic demands.In addition to protein phosphorylation,other post-translational modifications have been identified.Intracellular protein O-glycosylation,the addition of the simple sugar O-linked N-acetylglucosamine (O-GlcNAc) to serine/threonine residues,is a relatively recently identified post-translational modification that has added to the com...  相似文献   
935.
ObjectiveWe conducted this study with the aim of predicting the biological behavior of meningiomas, and determining the benefits of associating histological subtype and grade with the expression of proliferative markers and tumor suppressor proteins. MethodsThe study included 29 patients with primary intracranial and intraspinal meningioma diagnosed in the pathology laboratory of Konya City Hospital between January 2014 and December 2020. Clinicopathological characteristics of the patients including parameters such as age and gender were obtained from the hospital records. Histopathological findings were obtained by re-evaluating the preparations stained with Hematoxylin-Eosin, which were extracted from the archive, and by evaluating new sections obtained from paraffin blocks of patients stained with Ki67, p53, and p57 immunohistochemical stains. ResultsA moderate correlation was found between tumor size and Ki67 proliferation index (PI) (p=0.003, r=0.530). There was no significant difference between grade I and grade II tumors in terms of p53 (p=0.184) and p57 (p=0.487) expressions. There were higher levels of Ki67 PI in grade II tumors. The histological subtypes of the tumor had no significant difference with Ki67 PI (p=0.018), p53 (p=0.662), and p57 (p=0.368) expressions. ConclusionIn order to obtain more definitive results, there is a need for studies, which are conducted with a greater number of patients and in multiple centers, and in which a long prospective follow-up is planned. The combination of histological, surgical, and imaging markers could make a more sensitive tool for predicting recurrence, and this could also be tested in future studies.  相似文献   
936.
Oocyte matched follicular fluid oxidant, antioxidant status, and pro- and anti-inflammatory cytokine levels were assessed to reveal a possible effect of local-intrafollicular levels of these markers on the individual oocyte with its quality, ability to achieve fertilization, further embryo development, and pregnancy. A cross-sectional study of infertile women with diminished ovarian reserve undergoing antagonist protocol in vitro fertilization (IVF); in the form of ICSI, and fresh single embryo transfer were included. When follicular fluid was collected, each ovarian follicle was aspirated independently, and each follicular fluid was collected into a separate test tube to match it with a single cumulus-oocyte complex obtained from the same follicle. Oocyte matched follicular fluid samples and blood specimens were taken from the participants. Relationships of total antioxidant status, total oxidant status, oxidative stress index, total thiol, interleukin (IL)-6, IL-8, and IL-10 levels of each follicle with oocyte grade, grade of transferred embryos, and pregnancy rate of a given follicle were assessed. A total of 23 infertile women with diminished ovarian reserve and 79 individual follicles of these women were assessed. Serum total oxidant status level of metaphase II (MII) group was significantly lower than non-MII group (P < .001). Follicular fluid IL-6 level of MII group was significantly lower than non-MII group (P = .005). Follicular fluid IL-8 value was significantly low with positive pregnancy results (P < .001). Serum oxidative stress status and follicular fluid pro-inflammatory cytokines were associated with IVF outcomes. This unique study might guide IVF practice with the aim of developing and establishing more effective therapeutic strategies and choosing embryos with more potential for success.  相似文献   
937.
Pelvic or pelviperineal cellulitis is a rare but serious complication of bartholinitis and can be life-threatening. It is described of polymicrobial nature. The diagnosis of pelvic cellulitis remains essentially clinical with signs of local inflammation.The interest of imaging, CT in particular, is to assess the extent of the infection and abcess.In this report, we describe 2 cases of pelvic cellulitis complicating a bartholin''s abscess caused by negative gram bacilli in 2 diabetic women in their sixties.  相似文献   
938.
939.
940.
Over the years, nitrogen-rich functional groups like tetrazole and its derivatives have received increasing interest in the chemistry of small molecules. There is a continuously growing interest in polymers decorated with nitrogen for potential biomedical applications because of their broad range of biological properties, such as being antibacterial, anticarcinogenic, and anti-inflammatory. On this premise, a new synthesis route is reported for nitrogen-decorated polymers via the combination of Ugi-azide four-multicomponent reaction (UA-4MCR) and thiol-ene polymerization. Accordingly, α,ω-diene monomers decorated with (bis-)1,5-disubstituted-1H-tetrazoles ( bis-1,5-DS-Ts ) are synthesized by using the UA-4MCR. Subsequently, the light-induced thiol-ene polymerization facilitates the efficient synthesis of novel tetrazole-decorated polymers with apparent number average molecular mass (Mn) up to 62 000 g mol−1, which are characterized for their chemical, thermal, and optical properties. The comprehensive characterization of the synthesized polymers is paving the way toward a wealth of opportunities, ranging from biomaterials to energy storage−relevant materials.  相似文献   
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