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11.
Katsumi Kimura Naotaka Fujita Yutaka Noda Go Kobayashi Kei Ito Jun Horaguchi Toshiki Sugawara Osamu Takasawa 《Digestive endoscopy》2004,16(1):54-57
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer. 相似文献
12.
Shuichi Umeoka Koichi Baba Kiyohito Terada Kazumi Matsuda Takayasu Tottori Naotaka Usui Keiko Usui Fumihiro Nakamura Yushi Inoue Tateki Fujiwara Tadahiro Mihara 《Epileptic Disord》2007,9(4):443-448
We report a patient manifesting seizures with bilateral symmetric tonic posturing, which were markedly reduced after resection of the left precuneus. A 16-year-old man had sudden onset, complex partial seizures with bilateral symmetric tonic posturing since the age of eight years. Magnetic resonance fluid-attenuated inversion-recovery imaging revealed a hyperintense lesion in left precuneus. In almost all focal seizures recorded during an invasive EEG evaluation, ictal onset was detected from the inferomesial aspect of the lesion, but fast paroxysmal discharges from the ipsilateral supplementary motor area (SMA) were observed just before the clinical onset. After surgical excision of the EEG onset zone, including the lesion, seizure frequency was markedly (> 95%) reduced. By the 20th month after surgery, there were only brief nocturnal seizures involving slight elevation of both shoulders and slight abduction of both arms, with preservation of consciousness occurring once every few days. Invasive EEG findings and surgical outcome suggested that the epileptic activity originating from the epileptogenic zone may have propagated to the symptomatogenic zone including mainly the ipsilateral SMA. In summary, we report an interesting case of bilateral symmetric tonic posturing suggesting propagation to the SMA. MRI and invasive EEG confirmed the epileptogenic focus as a precuneate cortical dysplasia lesion.[Published with video sequences]. 相似文献
13.
Naotaka FUJITA Yutaka NODA Go KOBAYASHI Katsumi KIMURA Fukuji MOCHIZUKI 《Digestive endoscopy》1995,7(1):77-81
Pancreatic pseudocyst after pancreatic surgery is a relatively rare condition and conservative therapy is the common treatment of choice. When symptoms persist or complications follow, however, surgical treatment is considered. There have been reports on endoscopic cystoenterostomy since the early 1980s. We herein describe a case of postsurgical pancreatic pseudocyst treated successfully by endoscopic cystogastrostomy. A nineteen-year-old female showing left hypochondralgia and back pain with elevation of her serum amylase level, who had undergone enucleation of a solid cystic tumor in the body of the pancreas, was referred to our department. She was diagnosed as having a pseudocyst of the pancreas 5.8×4.5 cm in size at the site of enucleation by US and CT. Endoscopic retrograde pancreatography and endoscopic ultrasonography performed simultaneously revealed obstruction of the main pancreatic duct and a cystic change in the body-tail of the pancreas just behind the gastric wall of the upper body. An extrinsic compression was seen in the posterior wall of the upper body of the stomach endoscopically. An incision was made using a sphincterotome. A pigtail stent, 7.2 Fr in size, was placed to keep the patency of the fistula, which was removed one and a half months later. Her symptoms showed great improvement immediately after the procedure. Follow-up CT demonstrated no recurrence of the pseudocyst. 相似文献
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16.
Glomerular expression of cell-cycle-regulatory proteins in human crescentic glomerulonephritis 总被引:4,自引:0,他引:4
Kosaku Nitta Shigeru Horita Kazuho Honda Keiko Uchida Teruo Watanabe Hiroshi Nihei M. Nagata 《Virchows Archiv : an international journal of pathology》1999,435(4):422-427
To elucidate the mechanism underlying crescentic formation, we assessed the phenotypic characterization and cell-cycle protein expression in human crescentic glomerulonephritis (CRGN). Kidney tissue specimens taken from CRGN patients (10 patients with pauci-immune type rapidly progressive glomerulonephritis (RPGN), 2 patients with Henoch-Schönlein purpura nephritis, and 1 patient with IgA nephropathy) were examined immunohistochemically. Most of the cellular components of the crescents expressed cytokeratin, whereas few cells expressed PHM-5. CD68-positive cells were minor components of cellular crescents, indicating that the major principal cellular component of the crescents is made up of cells with the parietal glomerular epithelial cell (PEC) phenotype. Additionally, serial section analysis revealed that Ki-67-positive cells in the crescents were frequently cyclin-A positive and Bcl-2 positive, but seldom cyclin-B1 positive. Moreover, the expression of cyclin-dependent kinase inhibitor p27Kip1 was low in the cellular crescents, despite being exclusively positive in podocytes within the same section. We concluded that the major component of the cellular crescents is made up of PECs and that apparent expression of cyclins and Bcl-2 and restrained expression of p27Kip1 may be synergistically associated with the development of cellular crescents in human CRGN. 相似文献
17.
T. Yambe S. Nanka S. Naganuma S. Kobayashi S. Nitta T. Fukuju N. Uchida K. Tabayashi A. Tanaka K. Abe H. Takayasu M. Yoshizawa H. Takeda 《Journal of artificial organs》2002,5(1):1-5
Artificial circulation has been analyzed by decomposing it into parts. However, the sum of the decomposed parts is not equal
to the whole system, especially in nonlinear dynamic systems such as biological systems. To evaluate prosthetic circulation
as an entity, not as decomposed parts, nonlinear mathematical analytic techniques, including fractal dimension analyzing theory,
were used. Two pneumatically actuated ventricular assist devices were implanted as biventricular bypasses (BVB) in chronic
animal experiments using four healthy adult goats. For comparison between natural and prosthetic circulation in the same experimental
animals, the BVB-type complete prosthetic circulation model with ventricular fibrillation was adopted. All hemodynamic parameters
with natural and prosthetic circulation were recorded under awake conditions and calculated by a personal computer system.
By the use of nonlinear mathematical techniques, time-series data of the hemodynamics were embedded into the phase space,
and correlation dimension analysis was performed to evaluate the reconstructed attractor. Our results suggest that the correlation
dimension of the arterial blood pressure does not linearly increase according to the increase of the embedding dimension,
even during artificial circulation, suggesting those are the fractal time series data. Dimensional analysis of the hemodynamics
revealed that lower dimensional fractal dynamics were observed during prosthetic circulation. Fractal time series data are
suggested to have robustness and error resistance. Thus, our results suggest that the circulatory regulatory system with the
artificial heart may have these desirable characteristics.
Accepted: July 14, 1995 相似文献
18.
Urata M Nakamura N Kinoshita S Kayamori Y Hamasaki N 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(8):745-750
The examination of rheumatoid factor (RF), one of the diagnostic marker of rheumatoid arthritis (RA), showed negative about 25% of patients with RA. We analyzed a matrix metalloproteinase-3 (MMP-3) and a carbohydrate in rheumatoid factor (CA.RF) for diagnosis of RA: the former is used the kit "Panaclear MMP-3[Plate]" and the latter is used the kit "Picolumi CA.RF". The basic study of these reagents showed satisfactory results. In 73.3% of seronegative RA showed positive on both MMP-3 and CA.RF levels in serum, respectively. We found that these examinations might be useful for diagnosis of RA, especially during seronegative RA. 相似文献
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20.
Yoshizawa M Sato T Tanaka A Abe K Takeda H Yambe T Nitta S Nosé Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(4):443-448
The present study has proposed a new method for estimating the pressure head (P(t)[mm Hg]) and flow (Q(t)[L/min]) of a centrifugal pump on the basis of voltage (V(t)[V]), current (I(t)[A]), and rotational speed (N(t)[k(rpm)]) of the DC motor for a pump without any additional sensors. In the proposed estimation method, two auto-regressive exogenous (ARX) models are employed. One ARX model has an output, P(t) or Q(t), and three inputs, VI(t) = V(t)I(t) and N(t) and the steady state gain (K) of the system from VI(t) to N(t). It can be assumed that K may include the information on viscosity of blood. The coefficient parameters of this ARX model are identified in an off-line fashion before implantation of the pump. After implantation, P(t) or Q(t) is estimated by the same ARX model with the already identified parameters. The other ARX model is used to identify Kon the basis of VI(t) and N(t) in an on-line fashion every time the viscosity of blood may change. In the experiment, a mock circulatory system consisting of a centrifugal pump and a reservoir with 37% glycerin or water was employed. The root mean square error between measured Q(t) and its estimate obtained from the proposed method was 1.66L/min. On the other hand, a different method based on a single ARX model with inputs of VI(t) and N(t), but without the additional input of K, yielded the corresponding estimation error of 2.22L/min. This means that the proposed method can reduce its estimation error by about 25% in comparison with a method that cannot cope with the change in blood viscosity. 相似文献