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121.
For the cancer cells which have overcome the second mitotic clock (M2), activated telomerase is essential and used as another marker of immortality. Many trials had been initiated to target telomerase, which is known to be specific to tumors. To determine the best in vitro cell system for testing the efficacy of telomerase inhibitors, we evaluated the telomerase activity of various cancer cell lines and measured their telomere lengths. We also treated some cancer cell lines with adriamycin and measured the changes of telomerase activity. Telomerase activity was evaluated in various cell lines with the TRAP (telomeric repeat amplification protocol) assay. Telomerase activity was calculated and translated into arbitrary units by computer-assisted densitometry with the control of telomerase activity in the 293 control cell line. Also, terminal restriction fragment lengths were measured using Southern blotting. We also measured telomerase activity and telomere lengths in 11 benign breast tumor tissues and 19 paired stomach cancer and normal tissues. Cancer cell lines treated with adriamycin we evaluated for changes of telomerase activity and the cell proliferation by MTT assay and dye exclusion test. Telomerase activity of cell lines was 95.3 24.1 unit with a range of 27.6-129.6 unit, while the telomere lengths of those cell lines were variable from 5.0 to 10.4 kbp with a median of 6 kbp. In 11 cancer cell lines which were not yet firmly established, we could not detect any telomerase activity. Low telomerase activity was detected in only 2 benign tumor tissues of breast with a median telomere length of 8.8 (7-10.5) kbp. Among paired 19 gastric cancer and normal tissues, only 7 cancer tissues showed weak telomerase activity. After adriamycin treatment, telomerase activity in YCC-S-1, YCC-S-3, MCF-7 and MCF-7/ADR was decreased in accordance with the changes of the cell numbers. Telomerase is specific to cancer tissues and is expressed differently from organ to organ. Telomerase activity by TRAP assay could be used as a chemosensitivity assay.  相似文献   
122.
The capabilities of current protein structure prediction methods have been assessed from the outcome of a set of blind tests. In comparative modeling, many of the numerical methods did not perform as well as expected, although the resulting structures are still of great practical use. The new methods of fold identification ('threading') were partially successful, and show considerable promise for the future. Except for secondary structure data, results from traditional ab initio methods were poor. A second blind prediction experiment is underway, and progress in all areas is expected.  相似文献   
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BACKGROUND: Infestation with Ascaris lumbricoides is seen worldwide. Recently, there has been much interest in the pancreatic-biliary complications of Ascaris infection. In this study, we present our experience of 300 patients seen in a tertiary referral center. MATERIALS AND METHODS: Case charts of patients seen in the Department of Gastroenterology, University of Damascus, Syria, were analyzed, retrospectively, over a 5-yr period (September of 1988 to August of 1993). During this period, 1666 endoscopic retrograde cholangiopancreatographic studies were performed and pancreatic-biliary ascariasis was diagnosed in 300 patients (18%). RESULTS: The most common presenting symptom was abdominal pain, seen in 98% of patients (294 patients). Complications observed were ascending cholangitis (48 patients; 16%), acute pancreatitis (13 patients; 4.3%), and obstructive jaundice (4 patients; 1.3%). History of worm emesis was present in 25% of patients (76 patients). Most patients (240 patients; 80%) had previously undergone a cholecystectomy or an endoscopic sphincterotomy (232 patients; 77%). Worms were successfully extracted endoscopically in all except two patients, and there were no procedure-related complications. CONCLUSIONS: In endemic countries, ascariasis should be suspected in patients with pancreatic-biliary disease, especially if a cholecystectomy or sphincterotomy has been performed in the past. Endoscopic management results in rapid resolution of symptoms and prevents development of complications.  相似文献   
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An antibiotic producing Bacillus strain SR2, isolated from pea nut rhizosphere, showed in vitro antibiosis against many known plant pathogens. Seed bacterization with this strain showed an enhancement in seed germination, shoot height, root length, fresh and dry weights in four crop plants. A multiple drug resistant strain, SR2+, used to monitor root colonization confirmed the root colonization by the organism. Seed bacterization, reduced the number of chick pea wilted plants in wilt-sick soil, making the organism a potential bio-control agent against chick pea wilt.  相似文献   
127.
Burkholderia pseudomallei causes melioidosis and is believed to be an intracellular pathogen in human and animal disease. The uptake of B. pseudomallei by mouse peritoneal macrophages and cells in tissue culture was examined by electron microscopy. In all the systems studied B. pseudomallei were phagocytosed and apparently inhibited the normal processes of intracellular killing. Destruction of the phagosome membrane occurred and the bacteria escaped into the cytoplasm.  相似文献   
128.
Detection of thyroid nodules by physical examination and high-resolution ultrasonography was compared using small groups of blinded, experienced physician examiners working with a sample of 2441 persons from Estonia, most of whom were Chernobyl nuclear reactor clean-up workers. A random subsample of 113 (5%) persons was subjected to triple control examinations with both physical examination and high-resolution ultrasonography. Positive high-resolution ultrasonographic findings were considerably more reproducible among different observers than were positive physical examination findings. Agreement between methods was poor. Nodules were found in 169 (6.9%) subjects by physical examination and in 249 (10.2%) subjects by high-resolution ultrasonography. Physical examination found only 53 (21%) of the 249 nodules found by high-resolution ultrasonography. High-resolution ultrasonography did not confirm the existence of 115 (68%) of the 169 nodules found by physical examination. Only 6.4% of nodules less than 0.5 cm in diameter, as based on high-resolution ultrasonographic results, were detected by physical examination. Physical examination detection improved with increasing nodule size but was still only 48.2% for nodules larger than 2 cm. Physical examination was relatively effective in detecting nodules in the isthmus of the thyroid gland but much less so for nodules in the upper pole of the gland. Clinical evaluation and epidemiologic studies of nodular thyroid disease stand to benefit from the greater sensitivity and specificity of ultrasonographic examinations.  相似文献   
129.
Managing IBD in children and adolescents requires attention to issues unique to these age groups. The spectrum of presenting signs and symptoms is broad and often, subtle. Physician awareness of intestinal and extra-intestinal features prompts earlier diagnosis and intervention. The focus of treatment is not limited to intestinal symptoms, but also involves assessing weight and height gains, sexual maturation, extra-intestinal manifestations and psychosocial well-being. Differences in selecting drugs for pediatric versus adult patients are based on: 1. lack of prospective trials establishing effective doses for different ages; 2. inability to swallow capsules; 3. importance of nutrition in promoting growth; 4. paucity of data regarding the long-term safety of medications; 5. untoward cosmetic effects of corticosteroids, and 6. the need to develop coping mechanisms for a chronic illness. While sulfasalazine and mesalamine are useful in mild disease, corticosteroids are necessary for moderate and severe disease. Metronidazole and ciprofloxacin are effective in perianal CD. Elemental and polymeric formulas induce and maintain remission in active CD and reverse growth failure. Immunomodulatory agents (azathioprine and 6-mercaptopurine) enable physicians to reduce steroids and hospitalization. In practice, combination therapy is recommended to control symptoms and limit drug-induced side effects.  相似文献   
130.
Sporolactobacillus cellulosolvens (NCIMB 12173) isolated from an anaerobic digester and characterised biochemically is being reported for homofermentative lactic acid production from molasses in a batch culture. The effect of various process parameters on lactic acid production were optimized. A maximum lactic acid (24.2 g/l) and yield coefficient (0.79) was achieved using 3% (v/v) inoculum of 36 h old culture in molasses medium containing sugars (5%; w/v) supplemented with peptone (2.5 g/l) and (NH4)2SO4 (7.5 g/l), pH 6.5 at 40 degrees C after 72 h of fermentation.  相似文献   
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