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31.
Background: Gastrointestinal strictures are the most often and serious complication in Crohn's disease. Because of the frequent postoperative recurrence in Crohn's disease, endoscopic therapy of gastrointestinal stricture is one of the best therapeutic options. Method: The present study sets out the results from a prospective study of endoscopic dilation therapy on 48 Crohn's disease patients with severe gastrointestinal stenoses. All patients who could not undergo endoscopic balloon dilation therapy (EBD) were operated on. Results: Long‐term success was attained in 32 of the 48 patients; cumulative avoidance of surgery after EBD was 86% at one year and 71% at three. Second, the most hazardous factor was recurrent inflammation causing restenosis. Patients who had strictures with oral luminal dilatation and patients with frequent recurrence had a tendency to be operated on. As a complication, perforation occurred in two cases (3.3%). Conclusions: EBD therapy for Crohn's stricture in the gastrointestinal tract is recommended before surgical intervention.  相似文献   
32.
33.
Gallium scintigraphy was evaluated in 25 patients with adult T-cell leukemia lymphoma (ATLL). Anterior and posterior images were obtained at 72 h after administration of 3 mCi 67Ga-citrate using a gamma camera (Maxi-Camera 400T, General Electric Co.) with a medium energy standard parallel hole collimator. Abnormally high accumulations were observed in 17 out of 25 cases (superficial lymph node, 8; hilar and mediastinal lymph node, 7; paraaortic lymph node, 2; lung, 9; liver, 1; bone, 1). There were 10 malignant lesions detected by 67Ga scintigraphy in 9 out of 17 cases (superficial lymph node, 1; hilar and mediastinal lymph node, 6; paraaortic lymph node, 1; liver, 1; bone, 1). White blood cell count and serum LDH levels were raised in patients with abnormally high accumulations of 67Ga. In conclusion, 67Ga scintigraphy seemed to be a useful examination to detect malignant lesions in patients with ATLL.  相似文献   
34.
1. Intrarenal arterial infusion of hypertonic saline (HS) transiently increased and then gradually reduced renal blood flow (RBF) in anaesthetized dogs. Glomerular filtration rate (GFR) but not filtration fraction decreased at the end of the infusion. 2. In the presence of a potassium channel opener cromakalim (0.3 μg/kg per min), HS infusion failed to reduce RBF; the initial increase in RBF was maintained throughout the infusion. Since cromakalim also prevented the decrease in GFR, HS infusion lowered filtration fraction. 3. The results suggest that cromakalim inhibits both pre-and postglomerular vasoconstriction induced by HS infusion.  相似文献   
35.
An automated measurement of total and free hydroxyproline in serum or urine is presented that uses flow injection analysis. After exclusion of nonspecific substances, hydroxyproline was oxidized by chloramine- T and L-cysteine with Ehrlich's reagent. The linearity obtained was from 3.8μmole/ L to 1.22 mmole/L with good precision (CV <3%). Comparison of the proposed method with HPLC yielded r = 0.939 as the correlation coefficient. Reference intervals of free and total hydroxyproline are 1.4–9.7 μmole/L, 3.8–27.2 μmole/L for serum, and 10.0–72.5 μmole/L, 25.2–303.6 μmole/L for urine, respectively. Serum free and total hydroxyproline levels in renal osteodystrophy patients on maintenance hemodialysis (N = 71) were significantly higher than in controls (P<0.0001). This method is superior to the use of HPLC with regard to stability of the color reaction. The measurement of serum free and total hydroxyproline is a useful marker for therapeutic observation of renal osteodystrophy patients. © 1994 Wiley-Liss, Inc.  相似文献   
36.
We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells.  相似文献   
37.
Objectives: The pulmonary surfactant system of the human lung consists of unique lipids and proteins that contribute to the biophysical and innate immune properties of the organ. Surfactant protein A (SP‐A) is an oligomeric protein consisting of 18 protomers with collagen and lectin–like domains that recognizes glycoconjugates, lipids and protein determinants on both host cells and invading microorganisms. The authors examined the interaction of SP‐A with Mycoplasma pneumoniae and the influence of the protein upon the innate immune response to the bacteria. Methodology: The authors quantified SP‐A interaction with bacteria using ELISA, and identified the major surface ligand by thin layer chromatography, HPLC and mass spectrometry. The inflammatory response of human and rat macrophages was measured by quantifying tumour necrosis factor‐α secretion using ELISA, and nitric oxide production. Results: SP‐A bound the bacteria with high affinity and enhanced the inflammatory response of human and rat macrophages to the organism and its membranes. Analysis of the interaction of SP‐A with the bacteria revealed that the major ligand was a phospholipid. The lipid ligand was purified by a combination of thin layer and HPLC, and identified by mass spectrometry. The mass spectrometry demonstrated that the SP‐A reactive lipid consisted of several disaturated molecular species of phosphatidylglycerol (PtdGro). Additional experiments were performed to determine if disaturated PtdGro was capable of interfering with the action of SP‐A as an inhibitor of bacterial lipopolysaccharide‐induced inflammatory mediator production by macrophages. The disaturated PtdGro failed to alter the anti‐inflammatory action of SP‐A but unexpectedly these same studies revealed that unsaturated PtdGro can modify the host response to lipopolysaccharide. Conclusions: These findings reveal that both the lipids and proteins of pulmonary surfactant play a role in regulating the host response to invading microorganisms.  相似文献   
38.
A 58-year-old woman was admitted due to an abnormal shadow on chest X-ray, without any symptoms. Chest computed tomography showed a round mass in the anterior segment of the right upper lobe. Segmentectomy was performed and histopathological examination revealed a primary neurogenic tumor of Schwann cell origin. Immunohistochemical staining demonstrated the presence of S-100 protein in the tumor cells. We present a case of intrapulmonary schwannoma and review 62 cases of primary schwannoma of the lung.  相似文献   
39.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  相似文献   
40.
Malignant pulmonary artery tumors represented by sarcomas are rare, but fatal. Early diagnosis and radical surgical resection offer the only chance for survival. However, surgical intervention has some challenging aspects, and prognosis is poor even after tumor resection. We report a case of a pulmonary artery sarcoma between the right ventricular outflow tract and the pulmonary artery branches. The tumor was aggressively extracted with reconstruction using a cryopreserved pulmonary valved allograft, followed by adjuvant chemoradiotherapy. At 56 months after surgery, the patient is well without any evidence of recurrence, demonstrating that aggressive surgical resection with adjuvant chemoradiotherapy can prolong survival.  相似文献   
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