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51.
Tamaki Sasaki Tetsuya Sato Yoshiyuki Jyo Nobuya Tanda Hitoshi Tamai Gengo Osawa 《Clinical and experimental nephrology》1997,1(1):32-40
Background We previously found that glomerular epithelial cells play an important role in the formation of adhesive lesions. Glomerular
sclerotic lesions develop after the inital adhesive lesions.
Methods Two series of experiments were done with spontaneously diabetic WBN/Kob rats. These rats develop segmental glomerular sclerotic
lesions with aging. The first series of experiments was intended to clarify the kinetics of glomerular cells on progressive
glomerular damage in these rats. The second series of experiments was designed to study the relationship between proliferation
(judged by % bromodeoxyuridine-positive cells) of glomerlar epithelial cells and sclerotic lesions with adhesions.
Results In the first series, rats having increased proteinuria showed segmental glomerular sclerotic lesions with adhesions. At the
same time, increased labeling indices of tuft cells and epithelial cells of Bowman's capsule were observed. In the second
series, no significant increase in the labeling indices of tuft cells with sclerotic lesions was observed, compared to tuft
cells without sclerotic lesions. In sclerotic lesions with adhesion, bromodeoxyurdine-positive cells were observed that were
not distinguishable as podocytes or epithelial cells of Bowman's capsule. The highest labelling index was noted in the epithelial
cells of Bowman's capsules with sclerosis.
Conclusion This study shows that the proliferation of glomerular epithelial cells (mainly epithelial cells of Bowman's capsule) occurs
in glomerular sclerotic lesions with adhesions. 相似文献
52.
Prognostic significance of the expression of ras oncogene product in non-small cell lung cancer. 总被引:5,自引:0,他引:5
The clinical significance of ras oncogene expression in non-small cell lung cancer was evaluated in 116 surgically treated patients. Archival paraffin sections of the tumors were analyzed immunohistochemically using anti-ras p21 monoclonal antibody (MoAb) rp-35, and p21 staining was correlated with clinicopathologic parameters and survival. Positive reactions (+ and ++) were observed in 72.5% of the adenocarcinomas and 55.6% of the squamous cell carcinomas studied. The T1 tumors showed a ++ reaction less frequently than T2 and T3 tumors (P less than 0.05). Stage I tumors also were less reactive with MoAb rp-35 than tumors in more advanced stages (P less than 0.05). Survival analysis showed that patients with p21-negative tumors had significantly longer survival times (a 5-year survival rate of 64.1%) than those with p21 + tumors (38.0%, P less than 0.05) or those with p21 ++ tumors (11.5%, P less than 0.005). The significant correlation between p21 staining and patient survival was independent of histologic type, stage of disease, tumor or node status, and the resectability of tumors. On Cox's multivariate analysis, p21 staining was a major and independent prognostic determinant of survival. These results suggest that enhanced ras p21 expression may be one of the important biologic and clinical markers indicating the malignant potential of non-small cell lung cancer. 相似文献
53.
Yoichi Sato Hitoshi Yokoyama Masaaki Watanabe Osami Hamada 《Annals of thoracic and cardiovascular surgery》2003,9(6):401-405
A 74-year-old man with combined valvular disease with a recent cerebral infarction was admitted. While undergoing thorough examination for valvular disease, absent right superior vena cava (RSVC) and persistent left superior vena cava (PLSVC) were recognized. Chest X-ray film suggested a right arch protrusion, and CT and venogram confirmed the diagnosis. During surgery, replacement of the mitral and aortic valves and annuloplasty of the tricuspid valve were performed. A blood draining cannula was inserted in retrograde fashion from the coronary sinus into the PLSVC, without any difficulties in the tricuspid valve repair. Due to bradycardic atrial fibrillation, we believed that it would be difficult to insert an endocardial electrode postoperatively, hence myocardial electrode was placed in the right ventricular wall. Absent RSVC combined with PLSVC is very rare, and a patient who underwent combined valve surgery with this rare anatomical abnormality is herein presented. 相似文献
54.
55.
56.
T Kumagae T Harada A Furoi R Kamimura H Yoshida A Taira 《Nihon Geka Gakkai zasshi》1986,87(4):418-422
A simplified technique of the liver transplantation under hypothermia has been studied in dog. An immersion hypothermia was used in both the donor and the recipient. The temperature of the graft at excision was lowered to 20 degrees C with supplemental use of topical cooling. The temperature of the recipient was lowered at 27 degrees C when the transplantation was attempted. Chlorpromazine and dopamine were employed beneficially in hypothermia. No perfusion or irrigation of the graft was performed. The use of heparin was avoided. Anastomoses were carried out in turn of the proximal vena cava, portal vein, distal vena cava and the hepatic artery with a stem shaped aorta. Reperfusion was established after the completion of anastomosis between the proximal vena cava and portal vein. The anhepatic phase of the recipient was uneventfully lasted without heparinization. All dogs, 5 out of 11 without early surgical troubles survived more than 5 days. Immunosuppressive therapy was not employed except one which died of pneumonia on the 19th postoperative day. Histologically, these dogs were free from ischemic injury and/or thrombotic lesion throughout transplantation procedure. 相似文献
57.
Hideyuki Iwai Ryuji Koike Jun Ogawa Takahiko Sugihara Hiroyuki Hagiyama Kenji Nagasaka Yoshinori Nonomura Junko Nishio Toshihiro Nanki Rieko Tsubata Hitoshi Kohsaka Tetsuo Kubota Nobuyuki Miyasaka 《Nihon Rinshō Men'eki Gakkai kaishi》2002,25(3):270-276
A 36-year-old man was admitted to a hospital with complaints of fever, polyarthralgia and dyspnea. Erythema was observed on his face, extensor surface of the fingers and extremities, and a chest X-ray revealed massive bilateral pleural effusion. He had no sign of myopathy at this point. Pleural fluid was proved to be exudative and contained extremely high levels of hyaluronic acid. He was also complicated with interstitial pneumonitis and was given a pulse therapy with methyl prednisolone followed by daily administration of 55 mg prednisolone (PSL). Twenty days after the commencement of the therapy, pleural effusion decreased but muscle weakness gradually appeared, accompanied by elevation of myogenic enzymes. Myogenic changes on electromyogram, and irregularity of the muscle fibers with slight inflammatory cell infiltrates in a biopsy specimen were demonstrated. He was transferred to our hospital, and a diagnosis of dermatomyositis was made. Later, pleural effusion waxed and waned depending on the dosage of PSL, but no other causative disorder was demonstrated by extensive examinations. This case indicates that the pleuritis could be one of the vasculitic manifestations of dermatomyositis. 相似文献
58.
59.
In Vitro Evaluation of Platelet/Biomaterial Interactions in an Epifluorescent Video Microscopy Combined with a Parallel Plate Flow Cell 总被引:1,自引:0,他引:1
Nobuchika Kawagoishi Chisato Nojiri Kazuhisa Senshu Takayuki Kido Hirofumi Nagai Toshiyuki Kanamori Kiyotaka Sakai Hitoshi Koyanagi† Tetsuzo Akutsu 《Artificial organs》1994,18(8):588-595
Abstract: Suitable evaluation systems are critical for ranking various biomaterials in order to develop a method to design and synthesize nonthrombogenic biomaterials. We have recently developed an in vitro test system to evaluate platelet/biomaterial interactions in whole blood. The system consists of a parallel plate flow cell and epifluorescent video microscopy (EVM). A glass coverslip coated with a polymer was incorporated into the flow cell, and blood was perfused using a syringe pump via a polymer–coated PVC tubing connected to the flow cell. Whole human blood was anticoagulated with heparin (2 U/ml), and the platelets were labeled with the fluorescent dye mepacrine (5 μM). This system permitted real–time and dynamic observations of platelet/biomaterial interactions in whole blood under a defined flow condition. In order to evaluate the feasibility of this system, two different segmented polyether–polyurethanes (SPEUs), PU–PTMG(650) and PU–PTMG(2000), were chosen as test polymers. Surface characteristics verified with electron spectroscopy for chemical analysis (ESCA) and contact angle measurements showed similar results in both SPEUs. Blood was perfused at a wall shear rate of 200 s–1 for 20 min. Excitation light was applied for 2 s at 1 min intervals. The real–time image was then analyzed at each time point for the percentage of surface area of platelet coverage. Plasma β–thromboglobulin (β–TG) levels were also measured before and after each run. PU–PTMG(650) showed a significantly higher number of adhered platelets than PU–PTMG(2000) at each time point. β–TG levels of PU–PTMG(650) were also higher than those of PU–PTMG(2000), which is comparable to the results of EVM. Thus, this EVM system has been proven to be an excellent and highly sensitive in vitro analytical method for evaluating platelet/biomaterial interactions. 相似文献
60.
Detection limit in low-amplitude EEG measurement. 总被引:1,自引:0,他引:1
Electrocerebral inactivity for the determination of cerebral death is defined as no findings of EEG greater than the amplifier's inherent internal noise level when recording at increased sensitivity. A surface biopotential electrode contains two interfaces composed of skin gel (electrolyte) and gel electrode (metal), each forming a noise source. The power spectral density, S(f), of extremely low noise signals was obtained by means of autocorrelation and fast Fourier transformation. Interelectrode resistance, R(f), was measured with synchronous rectification. The formula of equivalent noise resistance R(n) = S(f)/4kT, where k is the Boltzmann constant and T is room temperature in Kelvin, gives a resistance that generates the thermal noise corresponding to the measured S(f). Rn/R is a parameter derived from normalization by R. When Rn/R = 1, measured noise contains thermal noise only. Meanwhile, Rn/R > 1 indicates presence of excess noise, such as 1/f, and tissue noise in addition to the thermal noise. Mean square root (Rn/R) of the scalp noise was 10.8 at 10 Hz, showing existence of excess noise. The study results suggest that it is necessary to take excess noise into consideration in the measurement of low-amplitude EEG for the determination of cerebral death. 相似文献