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21.
Implants of defatted, freeze-dried Saos-2 human osteosarcoma cells grown to confluency induce de novo bone formation in athymic mice. These cells are also richly endowed with bone morphogenetic proteins and express mRNA for bone morphogenetic proteins 1, 2, 3, 4, and 6, as well as for transforming growth factor-β1. Our aim was to study whether the ability to induce bone formation is related to the level of expression of bone morphogenetic protein. We studied the osteoinductive abilities and levels of expression of bone morphogenetic protein of Saos-2 cells both during the growth phase and after confluency was reached. Subconfluent cells were at least 70% less effective in their osteoinductive ability than confluent cells. Comparison of bone morphogenetic protein mRNA expression in confluent and subconfluent cells revealed that the latter had lower expression of all the mRNAs studied. The expression of bone morphogenetic protein-1, bone morphogenetic protein-2, and bone morphogenetic protein-6 mRNAs was 2, 3, and 6 to 10-fold lower, respectively, in subconfluent cells. These results suggest that the ability of Saos-2 cells to induce de novo bone formation may be correlated with the relative expression of these proteins; the expression of bone morpho-genetic proteins in Saos-2 cells also may be dependent on the cell cycle.  相似文献   
22.
The visit of Dr. Trendley Dean to Dublin in the mid-1950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities—the mean dmft is lower in children and the number of natural teeth present in adults is higher.  相似文献   
23.
Antidrug IgG antibodies have been detected in some patients receiving amodiaquine (AQ). Antidrug antibodies were detected in 6/7 patients who experienced serious well-defined adverse drug reactions during malaria prophylaxis and in 7/22 patients who received comparable doses of the drug (at least 400 mg weekly x 6) but did not present with clinical adverse drug reactions. In contrast antidrug antibodies were not detected in 7 patients who received the drug for treatment (1.0-1.2 g total over 3 days). The specificity of the IgG response was defined by hapten inhibition experiments (IC50 value for AQ ranged between 0.050 and 0.282 microM) which suggest that the antibody recognised the drug linked to cysteine residues in protein via the 4-hydroxyanilino side chain. The data show that AQ is immunogenic in man and are consistent with the hypothesis that idiosyncratic adverse reactions to the drug have an immunological aetiology.  相似文献   
24.
G Clarke 《The Practitioner》1992,236(1513):365-370
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Objective: To determine the effects of a total laryngectomy on the swallow and subsequent quality of life in head and neck cancer patients. Design: Cross‐sectional single centre cohort study. Setting: Head and Neck Oncology Unit, Tertiary Referral Unit. Patients: Sixty‐two patients who underwent total laryngectomy at our centre participated in the study. Methods: Subjects were stratified by age, sex, tumour stage, other procedures such as myotomy and nerve re‐implantation. Pharyngectomy, glossectomy, flap reconstruction, neck dissection and previous radio‐ and chemotherapy were also assessed to see if they affected swallow and subsequent quality of life. Main outcome was measured using the MD Anderson Dysphagia Inventory questionnaire. Results: Responses were received from 46 males and 16 females (response rate of 80.5%) with a mean age of 64.7 years (SD 9.4). Median follow‐up in patients was 90 months (range 1–276). The mean MD Anderson Dysphagia Inventory total score in our series of patients was 77.7 (SD 16.6). MD Anderson Dysphagia Inventory global score was 79.4 (SD 22.6), Emotional score was 77.7 (SD 17.8), Functional score 81.3 (SD 15.9) and Physical score was 74.1(SD 18). Statistically significant differences were seen between the emotional scores of glossectomised and non‐glossectomised patients (Mann Whitney, P = 0.04). No significant correlation was seen between the subscale scores and the remaining treatment variables such as age, gender, site, tumour stage, myotomy, nerve implantation, radiotherapy, reconstruction and major complications. Conclusion: This questionnaire study is the largest of its type to assess the swallow of patients who have undergone laryngectomy at a single centre. The overall result confirmed that most patients had a subjectively good swallow. Only glossectomy and the method of PE segment closure were shown to significantly affect swallowing outcomes following surgery. We recommend further work especially prospective studies pre and post surgery using this or similarly validated instruments to fully assess swallow in the laryngectomy population.  相似文献   
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We describe a case of cholangiocarcinoma in a young woman, who presented with cholestatic jaundice following oral contraceptive ingestion. Following diagnostic laparotomy she received intra-arterial 'lipiodolized' chemotherapy. Intravenous mitozantrone was given for 2 years and she is asymptomatic, with computed tomographic evidence of tumour response, 27 months after diagnosis. We suggest that this form of treatment is of value for cholangiocarcinoma.  相似文献   
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Background. Extreme hemodilution caused by relatively large prime volumes required for cardiopulmonary bypass in infants causes a dilutional coagulopathy, characterized by low concentrations of fibrinogen and other circulating coagulation factors. Modified ultrafiltration results in hemoconcentration and is associated with decreases in postoperative bleeding and transfusion requirements in children. This study was undertaken to quantify the effect of modified ultrafiltration on concentrations of fibrinogen, plasma proteins, and platelets in infants and small children.

Methods. Twenty patients less than 15 kg were studied. Cardiopulmonary bypass circuits were primed with crystalloid solutions. Red blood cells were added during cardiopulmonary bypass for hematocrits less than 15%. Colloid solutions were not administered. Concentrations of fibrinogen, plasma proteins, and platelets, and hematocrit were measured before cardiopulmonary bypass, before modified ultrafiltration, and after modified ultrafiltration.

Results. Modified ultrafiltration was associated with significant (p < 0.001) increases in hematocrit (19% ± 6% to 31% ± 9%), fibrinogen (65 ± 29 to 101 ± 45 mg/dL), and total plasma proteins (2.7 ± 0.3 to 4.9 ± 0.7 g/dL), but no change (p = 0.129) in platelet count.

Conclusions. We conclude that modified ultrafiltration significantly attenuates the dilutional coagulopathy associated with cardiopulmonary bypass in infants.  相似文献   

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