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31.
A morphologic histochemical study of phosphorylase was carried out to investigate the relationship between gastric carcinoma and intestinal metaplasia. Intense phosphorylase activity was observed in the carcinoma cells, especially in well-differentiated adenocarcinoma, and in the proliferating cells of some intestinal metaplasias. Metaplastic epithelium other than the proliferating cells occasionally showed a positive reaction. Phosphorylase was negative in normal gastric epithelium, even in its proliferating cells. There was an apparent coincidence between the location of well-differentiated adenocarcinoma and the distribution of intestinal metaplasia, with the proliferating cells showing positive reaction for phosphorylase. These data suggest that the relationship between the proliferating cells of intestinal metaplasia showing phosphorylase activity and well-differentiated adenocarcinoma is apparently closer than the much-debated relationship between the epithelium of intestinal metaplasia and gastric carcinoma. 相似文献
32.
Nishida K Doita M Takada T Shimomura T Maeno K Kakutani K Miyamoto H Kurosaka M 《Clinical calcium》2005,15(3):79-86
Intervertebral disc degeneration and associated spinal disorders including low back pain are a leading source of morbidity and a major cause of work disability as well as increased health care costs. Recent advance of molecular biology enable us to utilize these new techniques for understanding disc cell function and mechanisms of disc degeneration. Furthermore, these new technology may open novel therapeutic strategy such as application of growth factors, stem cell therapy, and gene therapy to regenerate degenerated intervertebral discs. 相似文献
33.
Aoyama T Shimizu T Matsuo T Sakamoto H Kamata K Higashihara M Tsuji H Shigematsu H Kobayashi Y 《Internal medicine (Tokyo, Japan)》2002,41(6):458-462
A 37-year-old woman had been found to have proteinuria in October 1996. About 8 months later, the first renal biopsy was performed, revealing focal segmental necrotizing and crescentic glomerulonephritis. At that time, serum creatinine was 1.0 mg/dl and urinary protein 3+. In October 1999, laboratory tests revealed positivity for MPO-ANCA and a serum creatinine level of 1.42 mg/dl, anemia and proteinuria of 2+. A second renal biopsy showed almost the same histological findings. Accordingly, a diagnosis of MPO-ANCA positive glomerulonephritis was made. This patient was thought to be a rare case of MPO-ANCA-positive slowly progressive glomerulonephritis presenting focal segmental tuft necrosis and crescents. 相似文献
34.
Atsuji Matsuyama Akio Sakamomo Takatoshi Aoki Masanori Hisaoka 《Pathology, research and practice》2013
Herein, we present a rare case of intraosseous leiomyosarcoma arising in the epiphysis of the distal femur and showing unusual radiographic features. A 44-year-old man presented with a pain in the left knee joint. Computed tomography revealed an intraosseous lesion with slightly increased attenuation and a thin marginal sclerotic rim in the femoral medial condyle. The signal of the lesion was hypointense on T1-weighted magnetic resonance (MR) images and hyperintense on fat-suppressed T2-weighted MR images. After gadolinium administration, the signal of the lesion was moderately and diffusely enhanced. The histological diagnosis of leiomyosarcoma was made based on a preoperative core biopsy specimen. Microscopic examination of the resected specimen revealed an ill-defined intraosseous tumor composed of proliferated atypical and mildly pleomorphic smooth muscle cells permeating among the bone trabeculae with only focal destruction of the bone trabeculae and low mitotic activity, indicating low grade leiomyosarcoma. The bone trabeculae at the periphery of the tumor were mildly thickened and anastomosed with a rim of an increased number of osteoblasts. Systemic examination showed no tumorous lesions in other anatomical sites. Leiomyosarcomas rarely present in the bone as a diffuse intertrabecular growth, even in low grade tumors. 相似文献
35.
Hiroo Takahashi Kaichiro Sawada Takatoshi Kakuta Takao Suga Kazuya Hanai Genta Kanai Satoshi Fujimura Noriyuki Sanechika Toshiro Terachi Masafumi Fukagawa Akira Saito 《Journal of artificial organs》2013,16(3):368-375
Bioartificial renal tubule devices (BTD) use cell therapy to improve conditions commonly observed in recipients of artificial kidneys for treatment of kidney diseases. We previously reported significant improvement of the condition of acute kidney injury (AKI) animals after treatment with BTD prepared with lifespan-extended human renal proximal tubular cells (hRPTEC). However, a major obstacle to use of BTD for patients is their biological safety, because hRPTEC are cultured in medium containing fetal calf serum. To establish the biological safety of BTD, we prepared BTD with lifespan-extended hRPTEC cultured in a newly developed serum-free medium and compared these with BTD prepared with hRPTEC cultured in serum-containing conventional medium. Lifespan-extended hRPTEC cultured in serum-free medium (hRPTEC-SFM) can proliferate similar to hRPTEC cultured in serum-containing conventional medium (hRPTEC-CM). Comparison of leakage and of reabsorption of small molecules for BTD prepared with hRPTEC-SFM (BTD-SFM) with those for our previous BTD prepared with hRPTEC-CM (BTD-CM) showed transportation in these two types of BTD was almost identical. When AKI goats were treated with BTD-SFM for 26 h, increase of survival time and reduction of cytokine expression in blood cells were almost same as for AKI goats treated with BTD-CM. Quantification of the expression of some genes of hRPTEC in BTD revealed significant changes during BTD treatment for AKI goats. In conclusion, lifespan-extended hRPTEC-SFM work as well as hRPTEC-CM, and the biological safety of BTD for patients could be elevated without loss of function by preparation from hRPTEC-SFM. 相似文献
36.
You-Sheng Li Naoki Kikugawa Dmitry A. Sokolov Fabian Jerzembeck Alexandra S. Gibbs Yoshiteru Maeno Clifford W. Hicks Jrg Schmalian Michael Nicklas Andrew P. Mackenzie 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
A key question regarding the unconventional superconductivity of remains whether the order parameter is single- or two-component. Under a hypothesis of two-component superconductivity, uniaxial pressure is expected to lift their degeneracy, resulting in a split transition. The most direct and fundamental probe of a split transition is heat capacity. Here, we report measurement of heat capacity of samples subject to large and highly homogeneous uniaxial pressure. We place an upper limit on the heat-capacity signature of any second transition of a few percent of that of the primary superconducting transition. The normalized jump in heat capacity, , grows smoothly as a function of uniaxial pressure, favoring order parameters which are allowed to maximize in the same part of the Brillouin zone as the well-studied van Hove singularity. Thanks to the high precision of our measurements, these findings place stringent constraints on theories of the superconductivity of .Obtaining a full understanding of the superconductivity of is a core challenge for condensed-matter physics. Since soon after its discovery over a quarter of a century ago (1), the superconducting order parameter of has been known to be unconventional (2, 3) and to condense from a well-understood and fairly simple quasi-two-dimensional Fermi liquid metallic state (4–7). Given the profound advances in theoretical techniques in recent decades a full understanding of its superconductivity is an important, and attainable, challenge for the field. The form of the wave-vector-dependent susceptibility of leads to the prediction of a rich superconducting phase diagram in weak-coupling calculations which aim to perform a bias-free estimate of the condensation energies of different order parameters. A notable feature of the results is how close a number of different odd- and even-parity solutions are seen to be in energy (8–10). On the one hand, this emphasizes the potential of as a test-bed material on which to refine the predictive capabilities of modern theories of unconventional superconductivity (11). On the other hand, realizing this potential will likely first require a conclusive experimental determination of which of the many possible order parameters wins out in the real material. This is a particularly exciting stage of the quest to complete this empirical determination, for reasons that we will now outline.For over 20 y the large majority of attention was paid to odd-parity order parameter candidates for (12), because of NMR measurements of spin susceptibility in the superconducting state that seemed to be inconsistent with any even-parity order parameter (13). However, thanks to the discovery of a systematic error in the original NMR measurements (14, 15), that situation has now been more or less completely reversed. Taking into account the most recent measurements of the magnetic field dependence of the spin susceptibility (16), it seems clear that the order parameter must be even-parity or at least dominated by an even-parity component. The spin susceptibility results would be most easily describable in terms of a single-component, likely -wave, order parameter, but recent thermodynamic evidence from ultrasound experiments is most straightforwardly interpreted in terms of an order parameter with two degenerate components (17, 18). Such order parameters do not of necessity break time-reversal symmetry, but they can, if the two degenerates have the appropriate phase relationship. In the context it is significant that long-standing muon-spin relaxation (SR) (19, 20) and magneto-optic Kerr rotation measurements (21) have indicated time-reversal symmetry breaking in the superconducting state.To investigate any order parameter with two degenerate components, whether or not it breaks time-reversal symmetry, uniaxial pressure is a powerful probe because it can split the degeneracy, creating a split superconducting phase transition (22). In a significant experimental advance, the muon-spin relaxation experiments have recently been extended to high uniaxial pressures (23). In line with naive expectation, the temperature at which time-reversal symmetry is broken () splits from the main superconducting transition (), with remaining nearly pressure-independent while increases under the application of the pressure. However, there has been a long-standing question about whether the Kerr and muon signals correspond to bulk thermodynamic transitions, so it is highly desirable to compare the new muon-spin relaxation data with those from a bulk thermodynamic probe. In this context, it is natural to look at heat capacity, because it has an intrinsic sensitivity to transitions within the superconducting state, as is well known from work on (24, 25). 相似文献
37.
Wakeyama T Ogawa H Takaki A Iwami T Kimura M Tanaka T Uchinoumi H 《Journal of cardiology》2004,44(2):73-79
A 61-year-old man was treated medically under a diagnosis of hypertrophic obstructive cardiomyopathy 7 years previously. He was transferred to our hospital because of sudden onset of dyspnea. Chest radiography showed marked pulmonary congestion. Echocardiography revealed hypertrophic obstructive cardiomyopathy, with a left ventricular pressure gradient of 120 mmHg, accompanied by severe mitral regurgitation due to ruptured chordae tendineae. Mitral valve replacement and the Morrow operation were performed. After the operation, no left ventricular outflow pressure gradient was detected by echocardiography and cardiac catheterization. The patient did well and no further cardiac symptoms were detected for 3 years. 相似文献
38.
Fumio Eto Naoki Wada Takashi Maeno Naoyuki Miyake Ikuko Saotome 《Geriatrics & Gerontology International》2004,4(S1):S202-S204
The effect of heel elevation of shoes in Parkinson's disease was analyzed by using two gait measurement systems. The heel elevation brought about some improvement of walking in the patients with Parkinson's disease with shortening of a stride period, a step period and the transition time of the plantar pressure peak from heel contact to toe off. After measurement study of the gait, all the patients answered the best heel height of shoes was higher than that of their casual footwear or the same. This simple treatment method may be also effective for fall prevention in patients with Parkinson's disease, and further investigation with follow-up observations should be necessary to verify the effect. 相似文献
39.
Hayashida K Kume N Murase T Minami M Nakagawa D Inada T Tanaka M Ueda A Kominami G Kambara H Kimura T Kita T 《Circulation》2005,112(6):812-818