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51.
A total 37 patients with Crohn's disease who underwent intraoperative endoscopy during resection of the affected intestine were evaluated in this study. The average age of the patients at surgery was 23.2 years. The residual lesions in the remaining intestine identified by intraoperative endoscopy were classified according to their pathologic profiles into three groups: A, B and C. In group A, comprising patients with longitudinal ulcers and/or a cobblestone appearance, 10 of 12 patients had recurrence. In 5 of these 10, the residual lesions were exacerbated and 2 required a further operation. The remaining 5 patients showed recurrence at the site of previous anastomosis and 2 of these 5 required additional surgery.In group B, comprising patients with small ulcers, aphthoid ulcers, or scars, and group C, comprising patients with no residual lesions, recurrence was observed in 13 of 16, and 3 of 9 patients, respectively. The recurrent lesions were all found proximal to, or at the site of previous anastomosis. Additional operations were performed on 3 of the group B patients. The findings of this study revealed that recurrence requiring additional surgery is more frequent at the site of anastomosis, regardless of the endoscopic appearance of the residual lesions.  相似文献   
52.
Objective: To induce adipocyte differentiation in vitro by adipose-derived stromal cells (ASCs) harvested from transgenic mice with green fluorescent protein (GFP) and assess the possibility of constructing adipose tissues via attachment of ASCs to typeⅡcollagen scaffolds. Methods: Inguinal fat pads from GFP transgenic mice were digested by enzymes for isolation of ASCs (primary culture). After expansion to three passages of ASCs, the cells were incubated in an adipogenic medium for two weeks, and the adipocyte differentiation by ASCs in vitro was assessed by morphological observation and Oil Red O staining. Then they were attached to collagen scaffolds and co-cultured for 12 hours, followed by hypodermic implantation to the dorsal skin of nude mice for 2 months. The newly-formed tissues were detected by HE staining. Results: The cultured primary stem cells were fibroblast-like and showed active proliferation. After being incubated in an adipocyte differentiation medium, the lipid droplets in the cytoplasm accumulated gradually and finally developed into mature adipocytes, which showed positive in Oil Red O staining. A 0. 5-cm3 new tissue clot was found under the dorsal skin of the nude mice and it was confirmed as mature adipose tissues by fluorescent observation and HE staining. Conclusions: ASCs can successfully differentiate adipose tissues into mature adipocytes, which exhibit an adipocyte-like morphology and express as intracytoplasmic lipid droplets. It is an efficient model of adipose tissues engineered with ASCs and type I collagen scaffolds.  相似文献   
53.
BACKGROUND: Otsuka Long-Evans Tokushima Fatty (OLETF) rats genetically develop diabetes which is associated with hypertension. In preliminary studies, urinary excretions of L-PGDS (lipocaline-type prostaglandin D synthase) increase before diabetic nephropathy obviously develops, and this may predict progression of renal injury following diabetes. In the present study, we attempted to define whether urinary excretions of L-PGDS behave as the predictor of development of diabetic nephropathy in OLETF rats. METHODS: We investigated alterations of urinary L-PGDS excretions during the establishment of diabetes and assessed the relationship between the L-PGDS excretions and renal function in OLETF rats. Furthermore, we treated OLETF rats with troglitazone and analysed the effects on L-PGDS metabolisms. Urinary L-PGDS was measured by immunoenzyme assay and the occurrence of L-PGDS and its mRNA in the kidney was assessed by immunohistochemistry and a PCR method. RESULTS: Urinary excretions of L-PGDS were significantly higher in OLETF rats than non-diabetic Long-Evans Tokushima Otsuka (LETO) rats. The excretions age-dependently increased in OLETF and this increase appeared to be due to increased glomerular permeability to L-PGDS. Messenger RNA and antigenicity of L-PGDS were demonstrated in renal tissue; however, the de novo synthesis of L-PGDS mRNA seemingly contributed to urinary L-PGDS excretions much less than glomerular filtration. Multiple regression analysis revealed that urinary L-PGDS was determined by urinary protein excretions, and not by high blood pressure per se. Conversely, urinary proteinuria in the established diabetic nephropathy was predicted by urinary L-PGDS excretions in the early stage of diabetes. CONCLUSIONS: Urinary excretions of L-PGDS are likely to reflect the underlying increase in glomerular permeability. This property may be useful to predict forthcoming glomerular damage following diabetes in OLETF rats.  相似文献   
54.
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   
55.
We developed a constant-flow perfusion system to measure vascular responses to vasoactive agents applied intraluminally or extraluminally. The intraluminal and extraluminal sides of a cylindrical section of rabbit basilar artery were isolated completely. By loading with 0.75 g of tension, the resting condition of each preparation was made constant. The intraluminal side was perfused at a constant flow of 8 ml/min and under an intraluminal pressure of 8 mm Hg. When 30 mM KCl was administered intraluminally the preparation showed marked contraction, whereas only slight contraction was observed with extraluminal administration. When 2 x 10(-7) M 5-hydroxytryptamine was administered, no significant differences in contraction could be detected between the intraluminal and extraluminal routes. Application of 10(-6) to 10(-4) M acetylcholine after precontraction with 30 mM KCl resulted in much stronger dilatation upon intraluminal application. Thus, it was demonstrated that under certain conditions significant differences exist in the responses of rabbit basilar arteries to vasoactive agents applied intraluminally or extraluminally. This system can detect the effects of vasoactive agents administered intraluminally and extraluminally at a high level of sensitivity and shows good reproducibility as a means of analyzing vascular functions and characteristics.  相似文献   
56.
The diagnosis and choice of treatment for dermatophytoses are usually based on the result of microscopic observation of hyphal elements and culture. However, false negative cultures have sometimes been encountered and appropriate timing of discontinuation of treatment has not been formulated. In this study, we attempted the identification and viability assessment of dermatophytes based on the quantitative measurement of dermatophyte actin (ACT) mRNA. An internal fragment of the ACT, 725 to 762 bp, was isolated by PCR from the genomic DNA of dermatophytes and sequenced. ACT intron-based primers were dermatophyte species-specific and primer pairs crossing the intron were dermatophyte genus-specific. The LightCycler (LC) instrument, employing the two-step RT-PCR/fluorescent hybridization system, was used to quantify the actin mRNA (ACT) of dermatophytes. A 669 bp ACT cDNA fragment was used as a quantification standard. Several mg of samples were collected from skin scales or nail plates before and after the treatment using oral terbinafine. The results indicated that quantification of ACT mRNA correlated with the results of culture and KOH examination and that copy numbers of dermatophyte ACT mRNA per mg sample decreased with progression of the therapy. This method comprises a sensitive (1 fg), specific, rapid (< 4 h) and quantitative assessment of the viability and identification of dermatophytes in skin tissue.  相似文献   
57.
To reevaluate the current features of spontaneous internal biliary fistulas, we reviewed 1,929 consecutive patients who had been treated for biliary tract diseases during the recent 12-year period. Thirty-three patients had internal biliary fistulas and the incidence was 1.9%. Of 33 patients, 20 were women and 13 were men with the average age 63 years, and their mean duration of illness was 4 years. A total of 37 fistulas were found and the most common type was choledochoduodenal (62%), followed by cholecystoduodenal (19%), cholecystocholedochal (11%) and cholecystocolonic (8%) fistulas. Internal biliary fistulas of thirty-one patients were caused by biliary stones and those of two patients by malignant tumors. All of the 17 bile samples examined were bacteria positive and the majority of calculi were brown pigment stones. All of the choledochoduodenal fistulas were correctly diagnosed by endoscopic retrograde cholangiography. In 14 patients with cholecystoenteric or cholecystocholedochal fistulas, direct evidence of the internal fistula was obtained only in 7 patients (50%) preoperatively. Pneumobilia, a small atrophic gallbladder adherent to the neighboring organs and a history of spontaneous disappearance of jaundice in elderly patients may indicate the presence of a cholecystoentric fistula. Since the preoperative diagnostic rate for internal biliary fistula involving the gallbladder is still low, care is necessary before and at the time of surgery especially during laparoscopic cholecystectomy for elderly patients with cholelithiasis.  相似文献   
58.
Prognostic significance of histologic parameters of soft tissue sarcomas.   总被引:3,自引:0,他引:3  
BACKGROUND AND METHODS. A univariate and multivariate analysis for the correlation between histomorphologic factors and prognosis was made using data from 1116 patients with soft tissue sarcoma, including 1005 cases available with complete histologic and follow-up data. RESULTS. The overall 5-year survival rate was 43.6%. The univariate analysis using Kaplan-Meier survival curves showed that tumor differentiation, cellularity, nuclear atypia, cellular pleomorphism, mitotic activity, amount of fibrous stroma, extent of myxoid areas, extent of tumor necrosis, and histologic grading (determined by the estimated range of malignancy for each type of sarcoma using a reported guideline) were all significant prognostic factors in the overall soft tissue sarcoma group. By a multivariate analysis using a procedure based on the Weibull model to failure data, the histologic grading and extent of tumor necrosis were proved to be prognostically significant in the overall sarcoma group. However, after additional analysis on each histologic type of sarcoma, it was determined that both tumor necrosis and histologic grading were applicable in only two types: malignant fibrous histiocytoma and leiomyosarcoma. Liposarcoma, synovial sarcoma, and malignant schwannoma each also showed some determinable factor of prognostic significance. CONCLUSIONS. It was concluded that there seemed to be no single universal prognostic parameter that could be applied to each soft tissue sarcoma type. These results suggest that the predictive significance of the various histologic parameters should be based on each specific type of sarcoma.  相似文献   
59.
Diastemstomyelia is an extremely rare disorder that is seldom found among the Japanese. This paper presents two Japanese patients, a newborn male and a newborn female, with diastematomyelia. CT demonstrated bony spurs more clearly than plain film, and magnetic resonance images indicated split cords and associated anomalies. Although the embryogenesis of diastematomyelia has not been clearly elucidated, the coincidence of levels of associated anomalies and diastematomyelia in our cases and in the literature supports Bremer's embryogenetic explanation of persistent accessory neurenteric canal.  相似文献   
60.
A phase I study of a recombinant gamma interferon (S-6810) was conducted in a cooperative study involving 11 institutions. S-6810 was administered at doses of 2, 4, 8, 12, 32 and 64 X 10(6) U/m2 by one-hour infusion for 5 consecutive days. A total of 40 courses were administered to 31 patients. High fever exceeding 38 degrees C with chills occurred in about 80% of patients. The incidences of other toxicities were fatigue in 50%, gastrointestinal toxicities in 30-40%, and changes in hepatic enzymes and hematologic toxicities in 20-30%. Dose-limiting factors were judged to be hypotension, leukopenia and central nervous toxicity. Maximum tolerated dose was 64 X 10(6) U/m2 and an optimal dose for phase II study was considered to be 6 X 10(6) U/m2 by daily chronic schedule. Blood concentration was highest at the end of infusion, and then decreased rapidly with a biphasic curve. The peak concentrations were elevated by escalation of doses. A partial response was observed in a patient with mycosis fungoides.  相似文献   
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