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131.
A 52-year-old woman was admitted to the hospital because of polyarthralgia and dry coughing. A chest X-ray film showed bilateral diffuse reticulo-nodular shadows. A specimen obtained by transbronchial lung biopsy revealed alveolar septal thickening and infiltration by mononuclear cells. Interstitial pneumonia associated with rheumatoid arthritis was diagnosed. Interstitial pneumonia relapsed soon after the first pulse of corticosteroid therapy. Cyclophosphamide pulse therapy was given in addition to a second pulse of corticosteroid therapy; 700 mg of cyclophosphamide (500 mg/m2) was administered intravenously every month and the dose of steroids was gradually reduced. Cyclophosphamide pulse therapy was repeated three times and the dose of oral corticosteroids was reduced from 60 mg to 35 mg. There was no bone marrow suppression or hemorrhagic cystitis after the cyclophosphamide pulses. Eventually, corticosteroid therapy was stopped with no clinical deterioration. This case suggests that intermittent cyclophosphamide pulse therapy can be effective for treatment of interstitial pneumonia unresponsive to corticosteroids.  相似文献   
132.
We describe herein the first successful implementation of intraportal stent placement combined with right portal vein embolization as preoperative management against far advanced gallbladder carcinoma. The patient was a 66-year-old woman with obstructive jaundice, in whom computed tomography confirmed that gallbladder carcinoma had invaded the liver and that massive lymph node metastases involved the hepatoduodenal ligament. Portography also revealed severe stenosis of the main portal trunk to less than 2 mm in diameter. To prevent the contribution of intraportal thrombosis and ensure postoperative liver functional reserve, an intraportal metallic stent implantation was conducted simultaneously with right portal vein embolization via a single route using the percutaneous transhepatic approach. There were no complications following this technique, and the patient subsequently underwent hepato-ligament-pancreatoduodenectomy. The resected specimen disclosed a well-expanded stent containing no thrombus. This method could therefore be an amenable strategy for the preoperative treatment of far advanced biliary malignancies in selected patients.  相似文献   
133.
BACKGROUND/AIMS: Resection of the caudate lobe of the liver is difficult to perform because of a deep location and an adjacency to the major vessels. METHODOLOGY: A total of 30 patients with hepatocellular carcinoma (HCC) originating in the caudate lobe underwent hepatic resection. The lobe was classified to Spiegel's portion, the process portion, and the caval portion. The operative procedure undertaken was chosen on the basis of tumor location as well as hepatic function of each patient. RESULTS: In 14 patients who had an HCC located at Spiegel's portion or the process portion, the tumor was removed by local resection of the caudate lobe (n = 10), or by resection combined with lobectomy (n = 2) or subsegmentectomy (n = 2). In 16 patients with an HCC at the caval portion, caudate lobe resections with preparatory lobectomy (n = 6), segmentectomy (n = 1), or subsegmentectomy (n = 4) were performed. In the other 5, isolated total or partial resection of the caudate lobe was carried out because of the presence of severe cirrhosis. All operations were defined as curative, but produced two operative deaths due to liver failure. The cumulative rate of overall survival was 41% at 5 years after surgery. CONCLUSIONS: Caudate lobe resection for HCC can be performed even in cirrhotic patients with a favorable surgical outcome.  相似文献   
134.
A translucent, conductive, porous nanocomposite was designed and prepared by depositing SnO2 on the inner surfaces of the pores of a porous glass plate and on its outer surface using a chemical vapor deposition method. The porous nanocomposite almost maintained its large surface area and pore volume because the pores remained open after they were deposited with SnO2. Conductivity between the two outer surfaces of the nanocomposite plate was confirmed for the first time.  相似文献   
135.
136.
Compact solid-State switched pulsed power and its applications   总被引:4,自引:0,他引:4  
Power semiconductor devices, such as insulated-gate bipolar transistors, metal-oxide-semiconductor field-effect transistors, and static-induction thyristors, are used in different kinds of pulsed power generators developed for different applications. In addition, the semiconductor opening switch is found to have very effective applications in pulsed power generation by inductive energy storage. Semiconductor switches have greatly extended the scales of pulsed power parameters, especially in repetition rate and lifetime. They have also enabled new areas of pulsed power applications, such as accelerators, flue-gas treatment, and gas lasers.  相似文献   
137.
The corrosion behavior of sialon ceramics was investigated in supercritical water at 450°C under 45 MPa for 2–50 h. α-sialon exhibited better corrosion resistance than β-sialon and α/β-sialon. Pitting corrosion with the formation of corrosion products was observed in the case of β-sialon and α/β-sialon. By contrast, the corrosion behavior of α-sialon was characterized by uniform corrosion with the formation of corrosion products. The degree of strength deterioration was strongly dependent on the corrosion morphology. The bending strength of α-sialon after corrosion for 30 h was about 90% of its initial strength, while the strength of β-sialon decreased to 65% of its original strength.  相似文献   
138.
A method for detecting the dimer of mono- and oligodeoxynucleotides is presented by using fast atom bombardment mass spectrometry (FAB-MS). The mass spectrum of a mononucleotide dpC showed an intense peak of the dimeric ion dpC:::dpC, compared with those of dpA, dpG and dpT. The mass spectrum of an equimolar mixture of dpC and dpG showed the highest peak of the dimeric ion dpC:::dpG, compared with all other combinations. The dimeric ion peaks in the mass spectra of dinucleotides d(ApT) and d(CpG) were relatively high and it may reflect the base-pairing energy due to hydrogen bonding. The degradation patterns of each dimers for d(ApT) and d(CpG) obtained by using the collision-induced dissociation (CID) technique which reflected the strength of each base-pairing.  相似文献   
139.
The preparation of platinum(II) complexes containing L-serine using K(2)[PtCl(4)] and KI as raw materials was undertaken. The cis-trans isomer ratio of the complexes in the reaction mixture differed significantly depending on whether KI was present or absent in the reaction mixture. One of the two [Pt(L-ser-N,O)(2)] complexes (L-ser=L-serinate anion) prepared using KI crystallizes in the monoclinic space group P2(1)2(1)2(1) with unit cell dimensions a=8.710(2) A, b=9.773(3) A, c=11.355(3) A, Z=4. The crystal data revealed that this complex has a cis configuration. The other [Pt(L-ser-N,O)(2)] complex also crystallizes in the monoclinic space group P2(1)2(1)2(1) with unit cell dimensions a=7.0190(9) A, b=7.7445(6) A, c=20.946(2) A, Z=4. The crystal data revealed that this complex has a trans configuration. The 195Pt NMR chemical shifts of trans-[Pt(L-ser-N,O)(2)] and cis-[Pt(L-ser-N,O)(2)] complexes are -1632 and -1832 ppm, respectively. 195Pt NMR and HPLC measurements were conducted to monitor the reactions of the two [Pt(L-ser-N,O)(2)] complexes with HCl. Both 195Pt NMR and HPLC showed that the reactivities of cis- and trans-[Pt(L-ser-N,O)(2)] toward HCl are different: coordinated carboxyl oxygen atoms of trans-[Pt(L-ser-N,O)(2)] were detached faster than those for cis-[Pt(L-ser-N,O)(2)].  相似文献   
140.
Aluminum hydroxide was used as a reactive filler to elastomers prepared from poly(oxypropylene)glycol (PPG), 2,4-tolylene diisocyanate (TDI), and 1,4-butane diol (BD). Mechanical properties, dynamic mechanical properties, and thermal properties were measured. Morphologies were observed by use of X-ray diffraction and scanning electron micrographs. The model reaction of isocyanate and aluminum was also studied. It was found that aluminum hydroxide fillers can be used for cost reduction without any detrimental effects on mechanical properties. Scanning electron micrograph studies of freshly cut surfaces of the aluminum filled elastomers showed that aluminum hydroxide is highly compatible with the elastomer. © 1994 John Wiley & Sons, Inc.  相似文献   
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