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41.
Summary In an effort to achieve a simple and less invasive method for the treatment of chronic subdural haematoma, replacement of the haematoma with oxygen by percutaneous subdural tapping was employed in 36 patients. This study was conducted on 23 haematomas in 20 patients, whose computed tomography (CT) scans immediately following the treatment were available for evaluation, with particular regard to distinguishing between their findings and those seen with tension pneumocephalus. The CT features werde divided into two patterns according to the location of oxygen; a convexity type (19 haematomas) and an interhemispheric type (4 haematomas). Analysis of the CT appearances revealed the oxygen was exclusively confined to the haematoma cavity, distinguishing it from the findings in tension pneumocephalus. This observation indicates the safety of replacement of the haematoma with oxygen when combined with our percutaneuous subdural tapping technique which prevents lesions of the inner haematoma membrane.  相似文献   
42.
Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors ( P <0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer.  相似文献   
43.
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy (JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery, and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion; the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor. This study was carried out as a group project. The authors' institutions are as follows  相似文献   
44.
Effects of TPE on prevention of hepatic failure after massive hepatectomy were studied experimentally using dogs. A 70% or 85% hepatectomy (Hx) was performed two weeks after TPE. All of the 70%Hx groups with(+)/without(-) TPE were alive for over two weeks after hepatectomy. While all of the 85%Hx group without TPE died, eight of ten in the 85%Hx group with TPE survived. Without TPE, total bilirubin levels in sera were elevated markedly in the 85%Hx group and moderately in the 70%Hx group after hepatectomy. The levels of escaped enzymes in sera, such as GOT or GPT, were also elevated remarkably in the TPE(-) groups. Although the levels of these enzymes were also high in the 85%Hx.TPE(+) group, these values were as same as those of 70%Hx.TPE(-) group. In the 85%Hx.TPE(-) group, critical diminution of functional hepatic cell mass and severe portal hypertension occurred after hepatectomy and coagulopathy and death followed to these phenomena. TPE might prevent the onset of these critical phenomena, and diminish the damage caused by massive hepatectomy. These results suggest that TPE is useful for prevention of postoperative hepatic failure so that we could perform massive hepatectomy safely, and extend the operative indication.  相似文献   
45.
The effects of platelet-derived growth factor (PDGF) on phospholipase D (PLD) activity and deoxyribonucleic acid (DNA) synthesis in rat C6 glioma cells have been investigated. Pretreatment of serum-starved C6 cells with PDGF results in enhanced choline production and the phosphatidylethanol (PEt) formation in the presence of ethanol, indicating the activation of PLD acting on phosphatidylcholine (PC). The dose-response curve for choline generation and DNA synthesis were comparable. In addition, the effects of PDGF on both PEt formation and [3H]thymidine incorporation into acid-precipitable material was blocked by the potent protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) but not by N-(2-guanidinoethyl)-5-isoquinolinesulphonamide (HA1004), a relatively weak inhibitor of PKC, suggesting that PDGF plays an important role as a positive regulator of glioma cell growth via a PLD-mediated mitogenic signal transduction cascades, which depends largely on the activation of PKC.  相似文献   
46.
N Ogura  Y Baba  I Sakai  K Taneichi  H Shibaki 《Ryūmachi》1992,32(5):508-14; discussion 512-3
We report a 28-year-old woman with systemic lupus erythematosus (SLE) who showed tubulo-interstitial nephritis (TIN) without any glomerular changes. In 1990, she was admitted to our hospital, complaining of anorexia, vomiting and persistent high fever. Laboratory findings showed proteinuria, pancytopenia, hypocomplementemia and positive for antinuclear antibody, anti-DNA antibody, anti-Sm antibody, anti-SSA antibody and anti-SSB antibody. We made a diagnosis of SLE. Furthermore, distal renal tubular acidosis and asteatosis cutis were revealed. The diagnosis of Sj?gren's syndrome was not made. We treated with high-dose prednisolone (60mg/day) and achieved improvement of symptoms and laboratory data. Open renal biopsy showed TIN without any glomerular changes. Predominant TIN is very rare in SLE. We discussed its pathogenesis and relation to the renal lesions of Sj?gren's syndrome.  相似文献   
47.
The complete nucleotide sequences of the variable region genes of the heavy and light polypeptide chains of a human monoclonal rheumatoid factor (RF) produced from a human-mouse heterohybridoma were determined. The antibody, designated YES8c, contained V kappa III, J kappa 2, VH1, JH4, and a D gene segment of 9 amino acids. The nucleotide sequences and the deduced amino acid sequences of the light chain variable region were remarkably homologous (97-98%) to previously described RF of the Wa idiotypic family (PAY, GLO, CUR, FLO, and GAR) and to that of a V kappa III germline gene (Humkv325). The YES8c heavy chain variable region gene was most closely related to the VH1 gene of the restricted human fetal repertoire, designated 51p1, and also to 3 rearranged VH1 genes that were recently isolated from patients with chronic lymphocytic leukemia. These results suggest that variable region genes of RFs are highly conserved and that YES8c VH, as well as V kappa, may be identical to heavy and light chains expressed during early B cell development.  相似文献   
48.
A 6-year-old boy was successfully operated on for double outlet ventricle, common atrioventricular canal with severe valvular regurgitation, right atrial Isomerism, L-loop ventricles, total anomalous pulmonary venous connection, and pulmonary stenosis with hypoplastic left pulmonary artery. The Interventricular rerouting from the left ventricle to the ascending aorta was performed with a spiral patch, the lnteratrlal switching was performed by a Mustard patch, the common atrioventricular orifice was partitioned and valve repair was performed, and an 18-mm valved conduit was inserted between the right ventricle and the pulmonary artery. Although the patient had a small residual ventricular septal defect and pulmonary stenosls, the patient Is alive and well.  相似文献   
49.
The purpose of this histological study was to determine the effects of photodynamic treatment, using a hematoporphyrin derivative and argon laser, on normal retinas of monkeys. Ten cynomolgus monkeys were treated with a hematoporphyrin derivative, given intravenously at a dose of 2.5 mg/kg. Forty minutes or 1 or 3 days after the injection, argon laser photoradiation was given over a 2.0-mm-diameter with a 10-min exposure and at an intensity of 40, 100, or 200 mW. The eyes were enucleated 1, 3, 4, 15, 18, 21, 35, or 38 days after the photoradiation and tissue samples were observed under a transmission electron microscope. The most fragile regions in the retina were the retinal nerve fibers, the outer segments of the visual cells, and the retinal pigment epithelium. Vascular endothelial cells were also fragile. The retinal capillary was easily obstructed, and the choriocapillaris was also occluded in an animal with severe retinal damage. The Mueller cells had the highest tolerance to the photodynamic treatment. Thus, exposing the normal part of the retina to light during photodynamic therapy should be avoided.  相似文献   
50.
TRK-100 (0.03, 0.1 and 0.3 mg/kg, p.o.), a chemically stable analogue of prostacyclin, dose-dependently prevented blood coagulation and glomerular fibrin deposition which were enhanced by 4 hr infusion of endotoxin (100 mg/kg) in rats. In addition, TRK-100 suppressed the generation of endotoxin-induced tissue thromboplastin like activity in cultured human endothelial cells.  相似文献   
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