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991.
992.
PURPOSE: The goal of the present study was to characterize the responses of the isolated normal canine prostate to various contracting and relaxing stimuli to determine which pharmacological agents may have utility against the dynamic component of benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Isometric force development was measured in isolated strips of prostate tissue. RESULTS: The alpha-adrenergic agonists were the most efficacious stimulants tested (phenylephrine EC50=2.1 microM.). Endothelin-1, acting primarily via ETA receptors, was more potent (EC50=27nM.) but less efficacious. Histamine (EC50=14.7 microM.), serotonin (EC50=0.12 microM.), carbachol (EC50=5.9 microM.) and KC1 (EC50=48.8 mM.) were also less efficacious than phenylephrine. Nifedipine was a potent (IC50=28 nM.) and efficacious (74% inhibition) inhibitor of phenylephrine-induced force. Potassium channel activator drugs were also efficacious relaxants, producing approximately 80% inhibition of force; rank order of potency was P1075 > cromakalim > diazoxide. Sodium nitroprusside was a weak relaxant, producing only approximately 40% relaxation at a concentration of 100 micronM. Both isoproterenol and forskolin were effective relaxants (75 to 90% relaxation). CONCLUSIONS: We conclude that potassium channel activators, adenylate cyclase stimulators, or endothelin antagonists may have utility against the dynamic component of outflow obstruction secondary to BPH.  相似文献   
993.
The XPF and ERCC1 proteins form a tight complex and function as an endonuclease to incise on the 5'-side of pyrimidine dimers in DNA. Levels of both proteins are extremely low in group F xeroderma pigmentosum (XP-F) cells. We transfected XP-F cells with the plasmids expressing XPF or ERCC1 and examined levels of both proteins in the cells. Although XP-F cells are sensitive to UV and mitomycin C (MMC), cells overexpressing XPF expressed ERCC1 as well and resistance to UV and MMC was restored to the normal level. In contrast, cells overexpressing ERCC1 did not express XPF and were still sensitive to UV and MMC. These results indicate that both the XPF and ERCC1 proteins are required to repair UV- and MMC-induced DNA damage. Even though a high level of ERCC1, which has been presumed to be a catalytic subunit of the endonuclease, is stably present in XP-F cells, ERCC1 protein alone cannot carry out excision repair completely.  相似文献   
994.
We herein report a case of pyelitis cystica in 65-year-old woman. She was referred to our hospital in order to have a treatment for a stone in the ureter on left side. Excretory urogram showed hydronephrosis on left, and multiple, small, smooth and round filling defects in the renal pelvis on right side. ESWL was performed to the ureteral stone, and the stone was discharged completely in 4 days. Then further examinations were made for the filling defects of right renal pelvis. Nonopaque calculi were ruled out on retrograde pyelogram and CT scan. Urinary cytology from the renal pelvis was class I. Our impression was pyelitis cystica of right kidney. Under spinal anesthesia, ureterofiberscopy was performed. Multiple small cysts were observed in the pelvis and calyx, as well as cystitis cystica. Cold cup biopsy was also done and histopathological finding ws pyelitis cystica, without malignancy. We compared endoscopic findings with radiographic findings in 18 cases of pyloureteritis cystica from the Japanese literature. The radiographic findings were multiple small, in a uniform size, and round filling defects with regular contour, and the endoscopic findings were multiple white or ocher colored, half sphere or sphere shaped, and small cyst with smooth surface in 15 of 18 cases. We thought these findings were characteristic ones in pyloureteritis cystica. Endoscopy and biopsy are mandatory for diagnosis of pyeloureteritis cystica.  相似文献   
995.
A patient with marked corneal astigmatism and inferior contact edge lift after penetrating keratoplasty for keratoconus had corneal relaxing incisions (CRIs) on the donor button and radial incisions on the host cornea. Results were evaluated by computerized videokeratography and by refitting the contact lens. Two pairs of CRIs decreased astigmatism from 11.00 to 4.25 diopters but did not alleviate the contact lens edge lift, which was caused by excessive steepness in the keratoconic host cornea. After 6 radial incisions were made to flatten the inferior host cornea, the peripheral cornea flattened and the patient was successfully refitted with a contact lens.  相似文献   
996.
To study how the T cell receptor interacts with its cognate ligand, the MHC/peptide complex, we used site directed mutagenesis to generate single point mutants that alter amino acids in the CDR3beta loop of a H-2Kb restricted TCR (N30.7) specific for an immunodominant peptide N52-N59 (VSV8) derived from the vesicular stomatitis virus nucleocapsid. The effect of each mutation on antigen recognition was analyzed using wild type H-2Kb and VSV8 peptide, as well as H-2Kb and VSV8 variants carrying single replacements at residues known to be exposed to the TCR. These analyses revealed that point mutations at some positions in the CDR3beta loop abrogated recognition entirely, while mutations at other CDR3beta positions caused an altered pattern of antigen recognition over a broad area on the MHC/peptide surface. This area included the N-terminus of the peptide, as well as residues of the MHC alpha1 and alpha2 helices flanking this region. Assuming that the N30 TCR docks on the MHC/peptide with an orientation similar to that recently observed in two different TCR-MHC/peptide crystal structures, our findings would suggest that single amino acid alterations within CDR3beta can affect the interaction of the TCR with an MHC surface region distal from the predicted CDR3beta-Kb/VSV8 interface. Such unique recognition capabilities are generated with minimal alterations in the CDR3 loops of the TCR. These observations suggest the hypothesis that extensive changes in the recognition pattern due to small perturbations in the CDR3 structure appears to be a structural strategy for generating a highly diversified TCR repertoire with specificity for a wide variety of antigens.  相似文献   
997.
PURPOSE: Velocity gradient data from phase-contrast magnetic resonance (MR) imaging were tested for the ability to calculate tensile strain and shear strain (deformation) during cyclical motion of skeletal muscle. MATERIALS AND METHODS: Strain data were derived from in vitro and in vivo phase-contrast MR velocity maps. A motion phantom designed to cyclically compress and expand a specimen of skeletal muscle provided a standard of reference to validate deformation, translation, and rotation measurements. The authors studied anterior and posterior muscle compartments of the lower extremity in three healthy volunteers during ankle dorsiflexion and plantar flexion against various resistances and the forearms of five healthy volunteers during flexion and extension of the fingers. RESULTS: The mean in vitro tracking error was 0.5 mm. The gastrocnemius muscle area in vivo changed 20% for both the minimum and maximum force conditions and therefore did not appear to be a good predictor of force. CONCLUSION: Phase-contrast MR imaging provides quantitative data on muscle contraction and demonstrates that shear and tensile strain can be measured and separated from translation and rotation of muscle.  相似文献   
998.
Twelve clinical isolates of Acinetobacter baumannii highly resistant to pefloxacin (MIC > or = 32 mg/L) and to ciprofloxacin (MIC > or = 16 mg/L), were studied. A susceptible isolate used as a reference (MIC of 0.032 and 0.25 mg/L for ciprofloxacin and pefloxacin, respectively) accumulated 85 mg of pefloxacin per litre of cell volume within 10 min, from a solution containing 10 mg/L of antibiotic. One resistant isolate accumulated the same amount of pefloxacin, while the 11 others accumulated between 40 and 70 mg/L of cell volume. The differences between reference and resistant isolates with respect to ciprofloxacin and sparfloxacin accumulation were less pronounced. There were no apparent differences in the outer membrane protein profiles of susceptible and resistant isolates. DNA gyrase was isolated from four A. baumannii and the minimum concentration of fluoroquinolones, required to inhibit gyrase-catalysed supercoiling of plasmid DNA was 5- to 80-fold higher for the resistant isolates than for the reference strain. Although most isolates showed some degree of reduced fluoroquinolone accumulation, a DNA gyrase mutation was more likely to be the main mechanism of the high level resistance encountered.  相似文献   
999.
BACKGROUND: Intrahepatic and extrahepatic factors are utilized by the surgeon in the decision-making process for the performance of hepatic resection for patients with colorectal metastases. Accurate preoperative and intraoperative staging are mandatory to avoid unnecessary surgery. In this report the intraoperative determinants of hepatic unresectability were evaluated. METHODS: This was a retrospective review of medical records from January 1985 to March 1996 of 62 patients with colorectal hepatic metastases who at the time of exploratory laparotomy were deemed to have unresectable disease based on intrahepatic or extrahepatic factors. The stage of the primary tumor, disease free interval, preoperative carcinoembryonic antigen, computed tomography portography, intraoperative ultrasound, and assessment of intrahepatic and extrahepatic tumor extension were evaluated. RESULTS: Intraoperative determination of the extent of required hepatic resection, including trisegmentectomy (9 patients; 15%) and total hepatectomy (10 patients; 16%), accounted for the majority of unresectable patients. Patients with > 4 metastases (8 patients; 13%) and satellitosis (6 patients; 10%) accounted for 23% of unresectable patients. Four patients had extensive nonmalignant hepatic parenchymal disease precluding resection. Thorough abdominal exploration revealed extrahepatic disease in 13 of 62 patients (21%). Routine periportal/celiac lymph node biopsies revealed metastases in an additional 12 patients (19%), 7 of whom (11%) had only periportal/celiac lymph node metastases. CONCLUSIONS: A meticulous abdominal exploration prior to hepatic resection for patients with colorectal metastases is essential to identify those patients with extrahepatic disease. Periportal and celiac lymph nodes commonly are involved by tumor. Therefore, routine periportal/celiac lymph node biopsies should be performed in the absence of other extrahepatic disease.  相似文献   
1000.
Infection of BALB/c mice with Trypanosoma cruzi resulted in up-regulated expression of Fas and Fas ligand (FasL) mRNA by splenic CD4+ T cells, activation-induced CD4+ T cell death (AICD), and in Fas: FasL-mediated cytotoxicity. When CD4+ T cells from infected mice were co-cultured with T. cruzi-infected macrophages, onset of AICD exacerbated parasite replication. CD4+ T cells from T. cruzi-infected FasL-deficient BALB gld/gld mice had no detectable AICD in vitro and their activation with anti-TCR did not exacerbate T. cruzi replication in macrophages. However, infection of BALB gld/gld mice with T. cruzi resulted in higher and more prolonged parasitemia, compared to wild-type mice. Secretion of Th2 cytokines IL-10 and IL-4 by CD4+ T cells from infected gld mice was markedly increased, compared to controls. In addition, in vivo injection of anti-IL-4 mAb, but not of an isotype control mAb, reduced parasitemia in both gld and wild-type mice. These results indicate that, besides controlling CD4+ T cell AICD and parasite replication in vitro, an intact Fas: FasL pathway also controls the host cytokine response to T. cruzi infection in vivo, being required to prevent an exacerbated Th2-type immune response to the parasite.  相似文献   
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