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81.
Calcification is the most common cause of damage and subsequent failure of heart valves. Although it is a common phenomenon, little is known about it, and less about the inorganic phase obtained from this type of calcification. This article describes the scanning electron microscopy (SEM)/energy dispersive X‐ray spectroscopy and Ca K‐edge X‐ray absorption near edge structure (XANES) characterization performed in natural and bioprosthetic heart valves calcified in vivo (in comparison to in vitro‐calcified valves). SEM micrographs indicated the presence of deposits of similar morphology, and XANES results indicate, at a molecular level, that the calcification mechanism of both types of valves are probably similar, resulting in formation of poorly crystalline hydroxyapatite deposits, with Ca/P ratios that increase with time, depending on the maturation state. These findings may contribute to the search for long‐term efficient anticalcification treatments.  相似文献   
82.

Purpose

The confusion of MRI sequence names could be solved if MR images were automatically identified after image data acquisition. We revealed the ability of deep learning to classify head MRI sequences.

Materials and methods

Seventy-eight patients with mild cognitive impairment (MCI) having apparently normal head MR images and 78 intracranial hemorrhage (ICH) patients with morphologically deformed head MR images were enrolled. Six imaging protocols were selected to be performed: T2-weighted imaging, fluid attenuated inversion recovery imaging, T2-star-weighted imaging, diffusion-weighted imaging, apparent diffusion coefficient mapping, and source images of time-of-flight magnetic resonance angiography. The proximal first image slices and middle image slices having ambiguous and distinctive contrast patterns, respectively, were classified by two deep learning imaging classifiers, AlexNet and GoogLeNet.

Results

AlexNet had accuracies of 73.3%, 73.6%, 73.1%, and 60.7% in the middle slices of MCI group, middle slices of ICH group, first slices of MCI group, and first slices of ICH group, while GoogLeNet had accuracies of 100%, 98.1%, 93.1%, and 94.8%, respectively. AlexNet significantly had lower classification ability than GoogLeNet for all datasets.

Conclusions

GoogLeNet could judge the types of head MRI sequences with a small amount of training data, irrespective of morphological or contrast conditions.
  相似文献   
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背景:有研究表明日间医院的康复服务与综合医院康复门诊比较,患者的功能和生活质量方面差异无显著性意义,但两者间有关脑卒中患者慢性期肢体功能的差异及其影响因素却少有报道。 目的:比较日本老年脑卒中患者慢性期分别在综合医院康复门诊和日间医院康复期间的肢体功能差异,分析影响功能差异的相关因素,以便改进老年脑卒中患者康复方案。 方法:分别对医院门诊和日间医院进行康复训练的老年脑卒中患者119例(年龄60~75岁)实施为期1年的调查分析,比较两组入选时和1年后的肢体功能指标的差异,包括健侧和偏瘫侧的股四头肌肌力、患侧膝关节伸展和踝关节背屈的关节活动度和10 m步行时间。采用逐步回归分析确定影响肢体功能指标变化的显著因素。 结果与结论:医院门诊组患者肢体健侧和偏瘫侧股四头肌肌力在入选时和1年后均大于日间医院组(P < 0.05),而两组的10 m步行时间差异均无显著性意义。医院门诊组在入选时患者患侧膝关节伸展和踝关节背屈关节活动度均小于日间医院组(P < 0.05),而1年后两组以上指标比较差异无显著性意义。逐步回归分析结果显示入选时健侧和偏瘫侧股四头肌肌力、患侧膝关节伸展和踝关节背屈关节活动度是其各自功能指标变化的显著影响因素,而偏瘫侧膝关节伸展、踝关节背屈的关节活动度越受限的患者,训练的效果越好。因此,日间医院组需要采取针对性的肌力增强或维持训练和膝关节活动度训练。  相似文献   
86.
We have investigated the inhibitory effect of oral administration of Juzen-taiho-to , a Kampo (Chinese herbal) medicine, on progressive growth of a mouse fibrosarcoma. Spontaneously regressive QR-32 tumor cells were able to grow progressively in vivo when coimplanted s.c. with a foreign body, gelatin sponge, whereas QR-32 cells alone gradually grew for over 15 days after inoculation and thereafter regressed for up to 25 days. Oral administration of Juzen-taiho-to (40 mg/day/mouse) for 7 days after inoculation of QR-32 cells with gelatin sponge resulted in significant inhibition of tumor growth and prolongation of the survival of the tumor-bearing mice. This growth-inhibitory effect of Juzen-taiho-to observed on day 25 was dose-dependent over the dose range from 4 to 40 mg/day. Treatment with Juzen-taiho-to for 7 days before tumor inoculation with gelatin sponge also significantly suppressed tumor growth examined on day 25, as did the administration of bismuth subnitrate, which is well known to induce metallothionein, an antioxidant. On the other hand, inoculation of progressed tumor cells (QRsP) resulted in growth without gelatin sponge, leading to death in syngeneic mice. Administration of Juzen-taiho-to for 7 days after inoculation of QRsP cells resulted in a decrease of the tumor growth and prolongation of the survival of mice, but the effect was less than that on the growth of QR-32 regressor tumor after coimplantation with gelatin sponge. These results suggest that the inhibitory effect of Juzen-taiho-to is partly associated with prevention of gelatin sponge-elicited progressive growth, probably mediated by endogenous factors including antioxidant substances, in addition to the augmentation of host-mediated antitumor activity.  相似文献   
87.
Abstact A solitary recurrence of gastric carcinoma in the peritoneal cavity is extremely rare. We herein present a case of solitary intraperitoneal recurrence in a patient with α-fetoprotein (AFP)-producing gastric carcinoma. As far as we can determine, this is the first report of such a form of recurrence in a patient with gastric carcinoma who underwent a successful resection. A review of our eight patients who had AFP-producing gastric carcinoma showed a frequent association with hepatic metastasis and a poor prognosis as has been reported previously. Our patient received intra-arterial chemotherapy with low-dose cisplatin and 5-fluorouracil to prevent hepatic recurrence, but eventually developed multiple hepatic metastases after ceasing this therapy. Therefore, adjuvant intra-arterial chemotherapy may have altered the site of first recurrence in this patient. Received: June 6, 2001 / Accepted: November 20, 2001  相似文献   
88.
PURPOSE: To investigate the ocular effect of intravenous administration of a phosphodiesterase type 3 inhibitor (NSP-805) and to compare the effect of NSP-805 with that of a calcium antagonist (nicardipine hydrochloride) on chorio-retinal blood flow in anesthetized albino rabbits. METHODS: Twenty-four female albino rabbits (weighting 2.0-4.0 kg) were anesthetized with intravenous injection. NSP-805(40 micrograms/kg and 100 micrograms/kg) and nicardipine of 40 micrograms/kg were intravenously administrated to the anesthetized rabbits. Intravenously administration of 20% dimethyl sulfoxide (DMSO) was used as a vehicle. Chorio-retinal blood flow was measured with a laser Doppler flowmeter at baseline and every 20 minutes after intravenous administration for 120 minutes. Heart rates and systemic blood pressure were monitored. Baseline measurements were compared with every 10 minutes after intravenous administration. Differences between the drug groups and vehicle group were analyzed. RESULTS: After administration of a low dose of NSP--805 (40 micrograms/kg) and nicardipine (40 micrograms/kg), the chorio-retinal blood flow was significantly increased (p < 0.05). A high dose NSP-805(100 micrograms/kg) reduced systemic blood pressure significantly, but the increase of chorio-retinal blood flow was less than that at the low dose of NSP-805(40 micrograms/kg) and nicardipine (40 micrograms/kg). Chorio-retinal blood flow in the NSP 805(40 micrograms/kg) and nicardipine (40 micrograms/kg) groups was significantly increased over that in the control group (20% DMSO) (p < 0.05). CONCLUSION: The results suggest that the NSP-805 has the potential of increasing chorio-retinal blood flow in rabbit eyes.  相似文献   
89.
Rat cytokine-induced neutrophil chemoattractants (CINCs) are the members of the CXC chemokine family. Four neutrophil chemokines, CINC-1, CINC-2 alpha, CINC-2 beta and CINC-3, were purified from the conditioned medium of granulation-tissue culture. CINC-2 alpha and CINC-2 beta differ only in the sequence of three carboxy-terminal residues and are produced by alternative splicing. CINC-3 had neutrophil chemotactic activity similar to that of CINC-1 and CINC-2, but induced greater calcium mobilization than CINC-1 and CINC-2. CINC-1, -2 and -3 induced calcium flux in CXCR2-transfected HEK293 cells. In addition, anti-CXCR2 serum inhibited neutrophil chemotactic activities of the three types of CINCs almost completely. These results indicate that rat CXCR2 is a unique receptor for CINC-1, -2 and -3. CINCs induced calcium mobilization through pertussis toxin-insensitive G-protein but induced chemotaxis through pertussis toxin-sensitive G-protein. CINC-1/-2 and CINC-3 may stimulate both G-proteins with distinct efficiency. The concentration of CINC-1 increased transiently in rat air pouch/lipopolysaccharide inflammation, whereas the CINC-2 level increased linearly. The number of infiltrated cells increased up to 8 h. The increase in cell number was correlated with the total concentration of CINC-1 and CINC-2. Northern blot analyses and enzyme-linked immunosorbent assay showed that CINC expression was very low in rat macrophages without stimulation and increased after lipopolysaccharide stimulation. These data suggest that CINCs are expressed by inflammatory cells such as macrophages at a site of inflammation and play important roles in neutrophil infiltration.  相似文献   
90.
Tryptase is a protease released from mast cells and is believed to contribute to the inflammatory process in allergic diseases including asthma. In the course of screening to find tryptase inhibitors, we isolated two new tryptase inhibitors, cyclotheonamide E4 (3) and E5 (4), from a marine sponge of the genus Ircinia. The structures of these molecules were determined by interpretation of 1H and 13C NMR spectra, and they were shown to be closely related to the previously reported cyclotheonamides E (1), E2, and E3 (2). These molecules contain two unusual amino acids, vinylogous tyrosine and alpha-ketohomoarginine, which are involved in strong activities against serine proteases. Cyclotheonamide E4 showed potent inhibitory activity against human tryptase (IC50 5.1 nM). Therefore, cyclotheonamide E4 may be useful as a therapeutic agent in the treatment of allergic diseases including asthma.  相似文献   
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