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The requirement for endoscopic access to a stricture is a major limitation of the endoscopic dilatation for the treatment of strictures in the gastrointestinal tract. We have developed the double‐balloon enteroscopy method that enables visualization of the entire small bowel. In addition, double‐balloon enteroscopy has a potential for the interventional therapy including dilatation of strictures. We present here a case of jejunal strictures in a 47‐year‐old woman with Crohn's disease successfully treated with a balloon catheter in combination with double‐balloon enteroscopy. Balloon dilation with double‐balloon enteroscopy is a promising method for the treatment of small bowel strictures in Crohn's disease.  相似文献   
3.
Febrifugine and isofebrifugine alkaloid mixtures extracted from the leaves and buds of Hydrangea macrophylla var. Otaksa, collected during different months, in Japan, were quantified using high-performance liquid chromatography. Leaves collected during the flowering season, namely from June to August, contained 0.16–0.31 mg/g of the alkaloid mixture, whereas those collected from September to December had less than 0.03 mg/g of the mixture. However, extracts of buds harvested from October to February contained a consistently larger amount (more than 0.49 mg/g) of the alkaloids. Hot-water extracts from the leaves and buds collected during different seasons were evaluated for antimalarial activity against Plasmodium yoelii 17XL in mice. The extract of leaves collected in August demonstrated high antimalarial activity, and all mice that received the extract survived the infection. In contrast, the extract of leaves collected in December showed little activity. The extract of buds collected in December cleared parasites, but with subsequent mortality to mouse. The present results show that the amount of antimalarial agent—febrifugine and isofebrifugine mixture—in H. macrophylla var. Otaksa is both part- and season-dependent, suggesting that the choice of plant parts and their harvesting season are important factors worth considering in the pharmacological use of medicinal plants.  相似文献   
4.
In order to treat fistulated esophageal cancer using a flexible stent, a covered flexible stent was constructed by wrapping a nitinol stent with a thin sheet of Gore-Tex, preserving the stents original advantages of flexibility and a low-profile introducer system. This stent was used to perform standard radiotherapy in a case of fistulated esophageal cancer.  相似文献   
5.
Although the leading causes of fever and pulmonary infiltrates in sickle cell patients are acute bacterial pneumonia and the acute chest syndrome, the former is usually responsive to antibiotics and not protracted, and the clinical course of the latter is short and self-limited. A patient with sickle cell anemia presented with fever and pulmonary infiltrates of several weeks duration that were unresponsive to antibiotics. Gross endobronchial abnormalities were noted on bronchoscopy, and the biopsies were consistent with sarcoidosis. The diagnosis of sarcoidosis can be difficult to establish in a patient with sickle cell anemia and protracted fever since both disorders are associated with chronic interstitial changes on the chest radiograph as well as restrictive physiology.  相似文献   
6.
Coronary artery bypass grafting with combined arterial graft using the left internal mammary artery (IMA), right IMA, and the right gastroepiploic artery (GEA) was performed in 45 patients with saphenous vein graft (SVG) (29 patients) or without SVG (16 patients) from February 1989 to October 1989. The left IMA was used in all patients, the right IMA was used in 9 patients, and the GEA was used in 43 patients. Perioperative myocardial infarction was noted in two patients who had hospital deaths. Reopening the chest for postoperative bleeding was performed in two patients, and the cerebral accident was noted in one patient. Fourteen patients were operated on without the requirement for blood transfusion. Studied within 3 postoperative months, all arterial grafts were patent though the patency was 97.7% (43/44) in SVG. It is concluded that the combined arterial graft utilizing the IMAs and GEA can be used safely and effectively.  相似文献   
7.
Axonal pathology is a major cause of neurological disability in multiple sclerosis. Axonal transection begins at disease onset but remains clinically silent because of compensatory brain mechanisms. Noninvasive surrogate markers for axonal injury are therefore essential to monitor cumulative disease burden in vivo. The neuronal compound N-acetylaspartate, as measured by magnetic resonance spectroscopy, is currently the best and most specific noninvasive marker of axonal pathology in multiple sclerosis. The possibility has been raised, however, that N-acetylaspartate is expressed also by oligodendroglial lineage cells. In order to investigate N-acetylaspartate specificity for white matter axons, transected rat optic nerves were analyzed by high-performance liquid chromatography and immunohistochemistry. In transected adult nerves, N-acetylaspartate and N-acetyl aspartylglutamate decreased in concordance with axonal degeneration and were undetectable 24 days posttransection. Nonproliferating oligodendrocyte progenitor cells, oligodendrocytes, and myelin were abundant in these axon-free nerves. At 24 days posttransection, N-acetylaspartate was increased (42%; p = 0.02) in nontransected contralateral nerves. After transection at postnatal day 4, total N-acetylaspartate decreased by 80% (P14; p = 0.002) and 94% (P20; p = 0.003). In these developing axon-free nerves, 25 to 33% of oligodendrocyte progenitor cells were proliferating. These data validate magnetic resonance spectroscopy measurements of N-acetylaspartate as an axon-specific monitor of central nervous system white matter in vivo. In addition, the results indicate that neuronal adaptation can increase N-acetylaspartate levels, and that 5 to 20% of the N-acetylaspartate in developing white matter is synthesized by proliferating oligodendrocyte progenitor cells.  相似文献   
8.
Denopamine (DP) is a new, orally active, selectively positive inotropic agent and used for the treatment of chronic cardiac insufficiency. The therapeutic effects of DP is highly related to its serum concentrations. A simple analytical method has been developed to determine the serum concentration of DP by use of high performance liquid chromatography (HPLC) with electrochemical detection (ECD). In order to extract the DP from the serum, a disposable solid extraction column (Sep-Pak cartridge, C-18) was used. The average recovery was 84.6 +/- 2.7%. The working electrode potential was fixed at 400 mV with a T1 cell, 600 mV with a T2 cell and 650 mV with a Guard cell in ECD. The analysis was performed on a Nova-Pak cartridge C-18 reverse-phase column (100 mm X 8 mm i.d., 4 microns). The mobile phase consisted of 0.1 M potassium phosphate buffer (pH 6.0) and acetonitrile (83: 17, v/v), and the flow rate was 1.0 ml/min. DP and internal standard phenolphthalein (PP) were eluted at 16.5 and 36.0 min, respectively. The peak-height ratio of DP to PP was linearly correlated (r = 0.9998) over a concentrations range between 1.25 and 15.0 ng/ml in the serum. The lowest detectable concentration was 1.0 ng/ml in the serum. The coefficient of variation of reproducibility in the assay was 6.0% By using the present method, serum concentration of DP was measured for four healthy volunteers after a single oral administration of 10 mg DP tablet after a overnight fast. From these DP concentration profiles, pharmacokinetic parameters were calculated.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
The current study investigates the effect of megestrol acetate, a synthetic progestin, on the activity of interleukin-1. Murine thymocytes were suspended in vitro and stimulated with varying concentrations of interleukin-1. [3H]Thymidine uptake was observed as an index of thymocyte proliferation. A dose-dependent increase in [3H]thymidine uptake was observed with increasing concentrations of interleukin-1. When megestrol acetate was added to the solution, a marked suppressive effect was observed. Higher doses of megestrol acetate had a greater suppressive effect on thymocyte proliferation. Additional investigation is required to further delineate the potential systemic effects of megestrol acetate.  相似文献   
10.
BACKGROUND: Gitelman's syndrome (GS) is an autosomal recessive disorder resulting from inactivating mutations in the thiazide-sensitive Na-Cl co-transporter (NCCT) gene. To date, almost 90 mutations have been identified. It is possible that there is a population-specific distribution of mutations. In this study, we analysed mutations in the NCCT gene of seven Japanese patients with GS. METHODS: Peripheral blood mononuclear cells were isolated from patients with GS, their family members and healthy control subjects. A mutation analysis of the NCCT gene was performed completely by direct automated sequencing of polymerase chain reaction-amplified DNA products. In patients with a deletion or splice site mutation, we undertook cDNA sequence analysis. RESULTS: We identified nine mutations. Five of them [c.185C>T (Thr60Met), c.1712C>T (Ala569Val), c.1930C>T (Arg642Cys), c.2552T>A (Leu849His) and c.1932delC] have been reported in Japanese patients, but not in GS patients from other ethnic groups. The remaining four mutations [c.7A>T (Met1Leu), c.1181_1186+20del26, c.1811_1812delAT and IVS16+1G>A] were novel. In cDNA derived from a patient with c.1181_1186+20del26, a deletion of exon 9 and a frameshift at the start of exon 10 were observed. In cDNA derived from patients with IVS16+1G>A, an additional 96 bp insertion between exons 16 and 17 was observed. Six out of seven patients were compound heterozygotes, and the remaining one carried a single heterozygous mutation. CONCLUSIONS: We found four novel mutations in the NCCT gene in seven Japanese patients with GS. Moreover, our study suggests that the distribution of mutations in the NCCT gene in Japanese GS patients potentially differs from that in other populations.  相似文献   
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