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81.
82.
Self-contained artificial lung prototypes were implanted in 8 dogs and a calf for periods up to eight days. Ventilation and perfusion of the artificial organ are provided by pressures available in the pleural cavity and the pulmonary artery through the use of a silicone rubber ventilating envelope and an efficient, low-pressure manifold system. The three units with the largest membrane area (0.208 to 0.832 sq. m. had flow rates of 65 to 240 ml. per minute and oxygen transfer rates of 1.4 to 13.0 cc. per minute with room air ventilation. Design characteristics and the problems with implantation and long-term function are discussed.  相似文献   
83.
BACKGROUND: Gallbladder cancer diagnosis is usually at a later stage. Only 1% of gallbladder cancers are discovered fortuitously at infra-clinic stage when histological exam of cholecystectomy specimen. Laparoscopic cholecystectomy was realised for gallbladder lithiasis or polyps. Port site metastasis after laparoscopy was reported. The aim of our study is to report our series of port site metastasis complicating gallbladder cancer discovered fortuitously after laparoscopic cholecystectomy. METHODS: From 1 January 1994 to 31 December 2004, 2562 laparoscopic cholecystectomy was carried out. Ten gallbladder cancers were diagnosed than the incidence was 0.39%. RESULTS: Gallbladder cancer diagnosis was carried out by histology in 8 cases, and when port site metastasis in two cases whereas histological exam of cholecystectomy specimen was negative. Recurrence of gallbladder cancer was in port site in 4 cases. The mean rate survival of patients with port site metastases was 19 months.  相似文献   
84.
An anomalous coronary artery to pulmonary artery fistula with concomitant aneurysmal dilation is quite rare, especially in the elderly. We present a case report of an 86-year-old female who presented with congestive heart failure from severe mitral regurgitation and was found to have such a coronary anomaly on preoperative angiography. The natural history, diagnosis, and treatment options are discussed.  相似文献   
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86.
Abstract – This experiment assessed the efficacy of the enamel matrix derivative (EMD) to regenerate cementum in vital and endodontically treated teeth with osseous dehiscence defects. Five adult female beagle dogs were used. Thirty maxillary teeth (bilateral maxillary canines and second and fourth premolars) were randomly divided into two experimental groups (groups A and B, containing 12 teeth each) and one control group (group C). Endodontic treatment was only performed on teeth in group A compared with teeth in groups B and C. Buccal osseous dehiscence defects were surgically created in teeth from all groups. Teeth in the experimental group were treated with the EMD, whereas the controls were not. After 5 months, the animals were sacrificed and block sections of the teeth in experimental and control groups were processed for histological analysis. Newly regenerated cementum was observed in all teeth in groups A and B. No cementum regeneration was observed in group C. There was a significant difference in cementum generation between the experimental and control groups (P < 0.001). EMD therapy induces cementogenesis in vital and endodontically treated teeth with osseous dehiscence defects.  相似文献   
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88.
AIM: To investigate eradication rates, patient compliance and tolerability of a 1-wk Azithromycin-based quadruple therapy versus the 2-wk conventional therapy. METHODS: A total of 129 H pylori-positive patients were randomized to either omeprazole 20 mg, bismuth subcitrate 240 mg, azithromycin 250 mg, and metronidazole 500 mg, all twice daily for 1-wk (B-OAzM) or omeprazole 20 mg, bismuth subcitrate 240 mg, amoxicillin 1g, and metronidazole 500 mg all twice daily for 2-wk (B-OAM). H pylori infection was defined at entry by histology and rapid urease test and cure of infection was determined by negative urea breath test. RESULTS: H pylori eradication rates produced by B-OAzM and B-OAM were 74.1% and 70.4% respectively based on an intention to treat analysis, and 78.1% versus 75.7% respectively based on a per-protocol analysis. The incidence of poor compliance was lower, although not significantly so, in patients randomized to B-OAzM than for B-OAM (3.5% versus 4.3%) but intolerability was similar in the two groups ( 35% versus 33.3%). CONCLUSION: 1-wk azithromycin based quadruple regimen achieves an H pylori eradication rate comparable to that of standard 2-wk quadruple therapy, and is associated with comparable patient compliance and complications.  相似文献   
89.
Transforming growth factor (TGF)-beta is critically involved in the activation of hepatic stellate cells (HSCs) that occurs during the process of liver damage, for example, by alcohol, hepatotoxic viruses, or aflatoxins. Overexpression of the TGF-beta antagonist Smad7 inhibits transdifferentiation and arrests HSCs in a quiescent stage. Additionally, bile duct ligation (BDL)-induced fibrosis is ameliorated by introducing adenoviruses expressing Smad7 with down-regulated collagen and alpha-smooth muscle actin (alpha-SMA) expression. The aim of this study was to further characterize the molecular details of TGF-beta pathways that control the transdifferentiation process. In an attempt to elucidate TGF-beta target genes responsible for fibrogenesis, an analysis of Smad7-dependent mRNA expression profiles in HSCs was performed, resulting in the identification of the inhibitor of differentiation 1 (Id1) gene. Ectopic Smad7 expression in HSCs strongly reduced Id1 mRNA and protein expression. Conversely, Id1 overexpression in HSCs enhanced cell activation and circumvented Smad7-dependent inhibition of transdifferentiation. Moreover, knock-down of Id1 in HSCs interfered with alpha-SMA fiber formation, indicating a pivotal role of Id1 for fibrogenesis. Treatment of HSCs with TGF-beta1 led to increased Id1 protein expression, which was not directly mediated by the ALK5/Smad2/3, but the ALK1/Smad1 pathway. In vivo, Id1 expression and Smad1 phosphorylation were co-induced during fibrogenesis. In conclusion, Id1 is identified as TGF-beta/ALK1/Smad1 target gene in HSCs and represents a critical mediator of transdifferentiation that might be involved in hepatic fibrogenesis. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).  相似文献   
90.
The antibacterial effects of gray-colored MTA (GMTA) and white-colored MTA (WMTA) against Enterococcus faecalis and Streptococcus sanguis were assessed in vitro using the tube dilution test. Broth tubes were prepared and divided into experimental and control groups. Aliquots of each of the tested microorganisms were taken from a stock culture and added to each experimental and positive control group. All groups were incubated at 37 degrees C and evaluated for turbidity at 0, 1, 24, 48, and 72-hour time periods. A direct correlation was found between GMTA and WMTA concentrations and their antibacterial effect. Tubes containing GMTA in concentrations of 50, 25, and 12.5 mg/ml did not show E. faecalis growth at any of the time periods tested whereas tubes containing WMTA showed E. faecalis growth at all concentrations and time periods tested. Statistically significant differences were found between tubes containing GMTA in concentrations of 50, 25 and 12.5 mg/ml and tubes containing similar concentrations of WMTA (p < 0.001). Tubes containing GMTA in concentrations of 50, 25, 12.5, 6.25, and 3.12 mg/ml and tubes containing WMTA in concentrations of 50, 25, and 12.5 mg/ml did not show S. sanguis growth at any of the time periods tested. Statistically significant differences were found between tubes containing GMTA in concentrations 6.25 and 3.12 mg/ml and tubes containing similar concentrations of WMTA (p < 0.001). It appears that the susceptibility of E. faecalis and S. sanguis to MTA differed and that GMTA requires lower concentrations than WMTA to exert the same antibacterial effect against each of the microorganisms tested.  相似文献   
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