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1.
Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability.  相似文献   
2.
Skin tumors were produced on the back of hairless mice, HOS (HR/De), by exposure to ultraviolet B light (UVB, 290–320 nm) with 4 different protocols. The first tumors appeared earlier (in 10 weeks in group I and 7 weeks in group III) when initial intense exposure was given, followed by repeated lower-level exposures, than when the mice were exposed to the repeated UV only (in 16 weeks both in group II and group IV). All mice developed skin tumors earlier in the groups given the repeated UV exposures three times a week than in the groups given the exposures twice a week. Most of the skin tumors produced by the UVB exposure were histologically malignant, being transplantable to nude mice, and the cultured cells grown from the tumors were capable of producing tumors when injected into nude mice. The accelerated development of skin tumors by initial intense exposure and short intervals of repeated exposure observed in this study may have implications for humans who expose themselves to intense sunbathing and UV tanning (burning) by fluorescent sun lamps.  相似文献   
3.
A 68‐year‐old man, who had no remarkable past medical history, was referred to a hospital because of disorientation and right‐sided hemiparesis. On magnetic resonance imaging, a contrast‐enhanced tumor in the left frontal lobe with perifocal edema was noted. He underwent left frontal lobectomy. Microscopic examination revealed infiltrative atypical astrocytes showing increased cellularity, distinct nuclear atypia, and many mitotic figures, while microvascular proliferation and necrosis were absent. Thus, the tumor was histologically diagnosed as anaplastic astrocytoma. It was of note that cytoplasmic eosinophilic granules were observed in approximately 25% of neoplastic cells. The granules were positively immunostained with anti‐αB‐crystallin antibody, and the other histochemical and immunohistochemical results also corresponded to Rosenthal fibers. The MIB‐1 labeling index of the highest area of the tumor was 22%, while that of granular cells was 2.1%. An ultrastructural study revealed amorphous electron‐dense structures attached to intermediate filament bundles, compatible with Rosenthal fibers. Such structures are relatively common in oligodendroglial tumors; however, they are extremely rare in astrocytic tumors. Fluorescence in situ hybridization targeted against chromosome 1 failed to demonstrate allelic loss of the short arm. The present case should also be discriminated from granular cell astrocytoma. We review related literature and discuss the significance of granules in gliomas.  相似文献   
4.
A case of a cervical cancer in a 40-year-old woman with a plasma carcinoembryonic antigen (CEA) level of 29.4 ng/ml was investigated using light and electron microscopy. In addition, the plasma CEA levels before treatment were determined in 168 patients with cervical cancer and in 33 patients with endometrial cancer. CEA was found to be elevated in the plasma of 19% of those with cervical cancer and in 6% of those with endometrial cancer. Effective serial plasma CEA determinations following therapy, in patients whose plasma or tumors initially contain elevated amounts of antigen, might be useful as an adjunctive method in the earlier detection of a recurrent cancer.  相似文献   
5.
We reviewed retrospectively 126 (5 male, 121 female) patients suffering from Takayasu arteritis who had been treated in our clinics from 1971 to 1990. The patients' ages ranged from 19 to 80yrs old (1990) with a mean age of 48.7 ± 11.8 years. HLA typing analysis in 98 patients revealed that 45 patients (47%) were confirmed as carrying the Bw52 antigen, a high result that is statistically significant as compared with that in healthy Japanese. Arteriograms (performed in 75 patients) revealed that 28 patients (37%) were affected in the aorta and its main branches by this disease (type IV by Nasu's classification) and 23 patients (31%) were affected only in the main branches (type I). The C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) improved significantly from 2.55 ± 0.28(+) and 57.0 ± 5.69 mm/hr to 0.53 ± 0.12(+) and 31.2 ± 3.45 mm/hr, respectively after treatment including steroid and antiplatelet therapy (P < 0.01).=" patients=" with=" bw52=" exhibited=" more=" severe=" inflammatory=" conditions=" than=" those=" without=" bw52.=" lung=" scintillations=" performed=" in=" 81=" patients=" showed=" pulmonary=" arterial=" lesions=" in=" 50=" patients=" (62%).=" echocardiograms=" revealed=" aortic=" regurgitation=" (ar)=" in=" 44=" patients=" (35%),=" with=" a=" significant=" difference=" noted=" between=" the=" bw52=" positive=" group=" and=" the=" bw52=" negative=" group=" [29/40=" (73%)=" versus=" 11/47=" (23%),=">P < 0.001].=" patients=" with=" bw52=" were=" prescribed=" higher=" doses=" of=" steroids=">P < 0.05)=" for=" longer=" periods=">P < 0.01)=" than=" those=" without=" bw52.=" of=" 11=" patients=" who=" died=" during=" our=" study=" period,=" 7=" died=" of=" cardiac=" complications,=" all=" of=" whom=" were=" suffering=" from=" ar.=" hla=" analysis=" performed=" in=" 6=" of=" these=" 7=" patients=" revealed=" that=" all=" carried=" the=" bw52=" antigen.=" in=" conclusion,=" the=" retrospective=" survey=" revealed=" that=" patients=" carrying=" the=" bw52=" antigen=" showed=" more=" severe=" inflammatory=" conditions=" and=" progressed=" more=" rapidly=" to=" complications=" and=" the=" fatal=" morbid=" condition,=" as=" compared=" with=" those=" without=" bw52.=" this=" suggests=" the=" important=" role=" of=" gene=" disequilibrium=" with=" this=" hla=">  相似文献   
6.
As a design for a biodegradable functional polymer, compositionally homogeneous poly[(sodium acrylate)-co-(vinyl alcohol)] [P(SA-co-VA)], containing varying amounts of vinyl alcohol groups as biodegradable segments were prepared and their biodegradability and builder performance in detergent formulations were analyzed with respect to the successive vinyl alcohol length. It was found that the acrylate copolymers having more than 80 mol-% vinyl alcohol content showed biodegradability. That is, P(SA-co-VA) having a vinyl alcohol chain length of more than about 5–6 is cleaved by PVA-degrading microbes. This indicates that the vinyl alcohol blocks, which act as biodegradable segments, should be incorporated into the polymer chain in such a manner that they are accepted as substrates by the PVA-degrading enzymes.  相似文献   
7.
Kallikrein was located in the apical portion of the striated duct cells of the cat's submandibular gland by an immunohistochemical technique. This portion only of these cells showed an intense band of specific fluorescence. There was no evidence of specific fluorescence in the acinar and demilune cells nor in the interstitial tissue or blood besells. In some sections the collecting ducts showed a very fine fluorescent luminal rim.  相似文献   
8.
A cement powder consisting of sodium calcium phosphate, Na3Ca6(PO4)5, in addition to tetracalcium phosphate and beta-tricalcium phosphate was prepared by pulverizing blocks of 4 wt% sodium-, 11 wt% carbonate-containing apatite samples that were heated at 1700 degrees C for 5 h. When mixed with 30 wt% malic acid or citric acid at a powder liquid ratio of 3:1, the cement set in 3 or 7 min at room temperature with compressive strength being around 52 or 27 MPa. In HeLa-cell cultures, the cement mixed with malic acid was less cytotoxic than the cement mixed with citric acid, which was far less cytotoxic than a commercial carboxylate cement used as a negative control, suggesting malic acid to be superior to citric acid as a liquid in this regard. Similar findings were also obtained with osteoclasts, of which culture experiments clearly suggested that the number of osteoclasts on the cement mixed with malic acid was significantly greater than that on the cement mixed with citric acid. Since osteoclastic response to substrates could be used as a maker in evaluating their bioresorbability associated with osteoclasts, the above finding may suggest that the cement that is to be mixed with malic acid would be more useful as bone substitutes.  相似文献   
9.
A molar ratio of free branched-chain amino acids to tyrosine (BTR) was determined in the plasma of patients with liver diseases using a new enzymatic method. In addition, clinical significance of BTR was studied by comparing particularly with that of Fischer's ratio (a molar ratio of branched-chain amino acids to aromatic amino acids (tyrosine+phenylalanine], which was obtained by conventional HPLC (Amino acid autoanalyzer, Hitachi 835). Following results were obtained: 1) Enzymatically determined branched-chain amino acids and tyrosine showed significant correlations with respective results obtained by HPLC (r = 0.937, 0.972). 2) Significant correlation was also found between enzymatically determined BTR and Fischer's ratio obtained by HPLC. Changes of BTR in clinical courses were found to be in parallel with those of Fischer's ratio. 3) BTR as well as Fischer's ratio correlated significantly with ICG R15, KICG, prothrombin time (%) and serum albumin level. 4) BTRs in patients with decompensated liver cirrhosis or with fulminant hepatitis were significantly lower than those in patients with acute or chronic hepatitis. In conclusion, new enzymatic assay of branched-chain amino acids and tyrosine as described here is quite simple method, and is also considered to be very useful parameter of the clinical conditions of patients with liver diseases, particularly representing the severity of liver diseases and the protein nutritional status.  相似文献   
10.
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