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991.
Implantation of a foreign material almost certainly results in the formation of a fibrous capsule around the implant however, mechanistic events leading to its formation are largely unexplored. Mast cells are an inflammatory cell type known to play a role in the response to material implants, through the release of pro-inflammatory proteases and cytokines from their α-granules following activation. This study examined the in vivo and in vitro response of mast cells to chitosan, through detection of markers known to be produced by mast cells or involved with the inflammatory response. Mast cells, identified as Leder stained positive cells, were shown to be present in response to material implants. Additionally, the mast cell receptor, c-kit, along with collagen, serglycin, perlecan and chondroitin sulphate were detected within the fibrous capsules, where distribution varied between material implants. In conjunction, rat mast cells (RBL-2H3) were shown to be activated following exposure to chitosan as indicated by the release of β-hexosaminidase. Proteoglycan and glycosaminoglycans produced by the cells showed similar expression and localisation when in contact with chitosan to when chemically activated. These data support the role that mast cells play in the inflammatory host response to chitosan implants, where mediators released from their α-granules impact on the formation of a fibrous capsule by supporting the production and organisation of collagen fibres.  相似文献   
992.
Background:  In diagnosis and treatment of obesity, body composition analysis including percent body fat (%BF) is useful in the clinical setting. Because bioelectrical impedance analysis (BIA) could be used quickly, easily and was non-invasive in clinical setting, the purpose of the present study was to evaluate the usefulness of multi-frequency BIA with eight-point tactile electrodes (MF-BIA8; InBody 720, Biospace) compared with dual-energy X-ray absorptiometry (DXA) in healthy children and adolescents.
Methods:  A total of 166 children and adolescents under 18 (male, n  = 86; female, n  = 80) were recruited. Height, weight, body mass index (BMI) and Tanner stage were measured for each subject. The body composition such as fat-free mass (FFM), fat mass (FM), and %BF was measured on BIA and DXA and compared.
Results:  On linear regression analysis, DXA FFM = 1.006(BIA FFM) + 0.554, R 2 = 0.99 and the standard error of the estimate (SEE) was 1.16 kg; DXA FM = 0.971(BIA FM) – 0.596, R 2 = 0.93; SEE, 1.34 kg; and DXA %BF = 0.940(BIA %BF) – 1.026, R 2 = 0.858; SEE, 3.03%. Limit of agreement in FFM, FM, and %BF was 0.7 ± 2.3 kg, −0.9 ± 2.9 kg and –2.2 ± 6.1%, respectively.
Conclusions:  Although the %BF was not interchangeable with DXA, MF-BIA8 (InBody 720; Biospace) could be used to measure body composition of children and adolescents in the clinical field because of its high precision.  相似文献   
993.
Buerger''s disease, or thromboangiitis obliterans, is a nonatherosclerotic inflammatory disease affecting the small- and medium-sized arteries and veins of the extremities (arms, hands, legs, and feet). It is most common in the Orient, Southeast Asia, India, and the Middle East, and usually affects men aged between 20 and 40 years, although it is becoming more common in women. It is well established that most such patients smoke heavily and experience an improvement in symptoms following smoking cessation. Mesenteric involvement in Buerger''s disease is extremely rare; however, we describe herein two cases of colon ischemia in patients who were previously diagnosed with lower-extremity Buerger''s disease. In one case, the patient developed colonic obstruction, and surgical resection was performed. Histopathologic findings were compatible with the chronic stage of Buerger''s disease. In the other case, angiography revealed abrupt occlusion of the inferior mesenteric artery with numerous collateral vessels, just like the corkscrew appearance found in the extremities. If patients with established Buerger''s disease of the extremities complain of gastrointestinal symptoms, early interventional diagnosis should be performed to prevent intestinal obstruction and gangrene.  相似文献   
994.
An undifferentiated (embryonal) liver sarcoma (ULS) originates from a primitive mesenchymal cell, with a predilection for childhood and very rare occurrence in adults. We report a case of a ULS that was incidentally found in a 53-year-old female. Our case was initially interpreted as a large hydatid cyst, which was later suspected to be a neoplastic lesion because its size was increasing and a solid portion was newly detected after shrinkage of the cyst following drainage. The patient underwent successful right hepatic lobectomy with complete resection, and is currently disease-free without adjuvant therapy. Although it is difficult to diagnose a hepatic cyst as a ULS due to its rare occurrence in adulthood and lack of specific findings, its possibility should be considered, especially when its size is increasing, because early diagnosis and curative resection are necessary for a favorable outcome.  相似文献   
995.
996.
997.
Since the occlusive‐type pulsatile extracorporeal blood pump (Twin‐Pulse Life Support System; Seoul National University, Seoul, Korea) received the CE mark of the European Directives and Korea Food and Drug Administration approval (2004) for short‐term applications as an extracorporeal life support system, the pump system has been tested for hemolysis. This pump system was recently upgraded with an ameliorated pusher plate to reduce hemolysis. In this study, numerical analysis and in vitro tests were performed to determine the optimal conditions for increasing the durability of the blood sac and pump output. During the simulation, the minimum sliding interface force (SIF) for the angle of the pusher plate movement (PPM) was calculated (40–70°). In the in vitro durability test, the angle of the PPM was increased gradually from 40 to 70° in 10° increments, and the mean time to failure (MTTF) of the blood sac was calculated. Fifteen tests were conducted for each case: 40, 50, 60, and 70° (n = 15 each). The MTTF of the blood sac was defined as the time when a crack of the blood sac occurred. The longer lifetime of the blood sac at 60° of the PPM (297.0 h) than that at 50° (197.6 h) was attributed to the lower SIF value (?0.13, normalized value) at 60° of the PPM.  相似文献   
998.
999.
OBJECTIVE: To assess the fetal outcome of three hypertensive women exposed to amlodipine. 5 mg/day, in the first trimester of pregnancy. CASE 1: The patient was treated with amlodipine until 7 weeks of gestation. She was also exposed to levosulpiride, aluminum hydroxide gel, magnesium carbonate, and Ginkgo biloba. At 38(+3) weeks of pregnancy, she delivered a 3750 g healthy female baby, and restarted taking amlodipine, 5 mg/day, while exclusively breastfeeding her daughter. At three months of age, the infant was healthy. CASE 2: The patient was treated with amlodipine from 2(+2) to 3(+4) weeks of pregnancy. Her treatment was modified to atenolol until the week 6(+4 weeks), when she declined any antihypertensive treatment. At 39(+4) weeks of pregnancy, the patient delivered a 2600 g baby. At 20 months old, the baby presented with intellectual delay and weakness in the left arm and hand grasp. These neurological alterations were not attributed to her exposure to amlodipine early in utero. CASE 3: The patient was treated with amlodipine from 7(+6) to 12 weeks of pregnancy. She was also taking sucralfate and lorazepam. At 12 weeks of amenorrhea, ultrasound revealed a 15.3 mm, single fetal pole in the gestational sac without cardiac activity. She underwent dilatation and evacuation of a dead embryo. CONCLUSION: As reported with other calcium-channel blockers, amlodipine does not appear to be teratogenic and it appears to be compatible with breastfeeding.  相似文献   
1000.
OBJECTIVE: To test the efficacy of a new scoring system to differentiate high-risk hydatidiform mole (H-mole) and initiate early selective postmolar chemotherapy. STUDY DESIGN: According to Kim's scoring system, 262 patients were identified as high-risk H-mole patients. Fifty (19.1%) received early chemotherapy, and the rest constituted the control group. Salvage therapy with etoposide, methotrexate, actinomycin D/etoposide, cisplatin (EMA/EP) and taxol, cisplatin/taxol, etoposide (TP/TE) was applied in 21 cases of ultra-high-risk GTT. RESULTS: None of the 50 cases in the early chemotherapy group progressed to persistent GTT. However, 58.9% in the control group developed GTT with 8.0% drug resistance. Of those receiving salvage therapy in the 21 ultra-high-risk GTT cases resistant to EMA/CO, 10 of 14 (71%) receiving EMA/EP and 4 of 7 (57.1%) receiving TP/TE achieved remission. CONCLUSION: Early postmolar chemotherapy for high-risk H-mole is effective in preventing progression to persistent GTT and treatment failure. Ultra-high-risk GTT should be approached with multimodal treatment, including EMA/EP and TP/TE regimens.  相似文献   
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