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1.
Abstract The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN® in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN® in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®.  相似文献   
2.
The effects of repeated doses of benzodiazepines, diazepam and midazolam in combination with meperidine on arterial blood gases and transcutaneous PO2 were studied in eight healthy volunteers. The study was designed to mimic a clinical situation. Initially two doses of either midazolam 0.05 mg/kg or diazepam in fat emulsion 0.15 mg/kg were given in a randomized crossover fashion with a 20-min interval, followed by meperidine 0.5 mg/kg another 20 min later. The opioid effects were then antagonized by naloxone 0.4 mg. The initial doses of benzodiazepines caused an increase in PaCO2 and a decrease in PaO2. The changes in PaO2 were of short duration and recovered to baseline levels between injections. However, they came sooner and were more pronounced after midazolam. The changes in PtcO2 paralleled those in PaO2. The PtcO2 index as a measure of cardiac output and peripheral blood flow adequacy was increased immediately after the first injection of midazolam but was otherwise not different from control. There were no differences between the drugs concerning PtcO2 index. PaCO2 increased after the first benzodiazepine injection and remained so throughout the study. Addition of meperidine caused only small changes in PaO2 and PaCO2. These changes were reversed by naloxone. In spite of different elimination kinetics there was no difference in the duration of respiratory depression between the two benzodiazepines.  相似文献   
3.
Experimental composites using either bisGMA/TEGDMA or UEDMA/ TEGDMA matrices, quartz or barium glass fillers, and 2 different filler silanization methods were evaluated regarding monomer leachability in distilled water. The leached amount was detected and quantified using gas chromatography. The results showed that twice as much TEGDMA is leached from a bisGMA/TEGDMA based composite than from an UEDMA/ TEGDMA based composite, when both contain 50 wt% TEGDMA. The hypothesis suggested that the higher degree of cure of UEDMA/TEGDMA based composites would be reflected in a lower monomer leaching value, and this hypothesis was supported by the findings. Whether such a correlation exists within groups of UEDMA/TEGDMA based matrices having different degrees of cure was not determined and needs to be investigated in future studies. Variables such as filler composition and silane treatment did not affect the leaching values of TEGDMA in water. That finding suggests that future studies should target differences in matrices, and that the need for considering effects of filler composition and silane treatment methods should not receive the same priority.  相似文献   
4.
The examination of monthly (or quarterly) increments in weight or length is important for assessing the nutritional and health status of children. Growth velocities are widely thought to be more important than actual weight or length measurements per se. However, there are no standards by which clinicians, researchers, or parents can gauge a child's growth. This paper describes a method for computing growth velocities (monthly increments) for physical growth measurements with substantial measurement error and irregular spacing over time. These features are characteristic of data collected in the field where conditions are less than ideal. The technique of smoothing by splines provides a powerful tool to deal with the variability and irregularity of the measurements. The technique consists of approximating the observed data by a smooth curve as a clinician might have drawn on the child's growth chart. Spline functions are particularly appropriate to describe bio-physical processes such as growth, for which no model can be postulated a priori. This paper describes how the technique was used for the analysis of a large data base collected on pre-school aged children in rural Haiti. The sex-specific length and weight velocities derived from the spline-smoothed data are presented as reference data for researchers and others interested in longitudinal growth of children in the Third World.  相似文献   
5.
The long term effects of the Unilink mechanical microvascular anastomosis in terms of anastomotic patency and histological changes in the vessel wall were evaluated in 10 rabbits. Both carotid arteries and facial veins were divided and reanastomosed with the Unilink device. At death two years later all 40 anastomoses were fully patent, with histological changes similar to those described previously after 16 weeks, that is, normal endothelial lining, but almost total atrophy of the media at the anastomotic site. The thinning of the vessel wall at the anastomosis caused neither occlusions nor aneurysms during the observation period.  相似文献   
6.
Postsynaptic dopamine (DA) receptor sensitivity was assessed during abstinence in 15 male patients with alcohol dependence. The DA receptor sensitivity was evaluated using growth hormone (GH) responses to the DA receptor agonist apomorphine (0.18-0.24 mg intravenously). The patients were cared for in an alcoholism treatment unit for the 2 months prior to the investigation. They were carefully controlled for sobriety during this period. Thirteen healthy men were used as controls. The maximum GH responses to apomorphine were significantly reduced in patients compared with those in the control group. The patients had a significantly higher proportion of blunted GH responses. The findings suggest reduced postsynaptic DA, possibly D2, receptor sensitivity in abstinent alcoholics. The question whether this abnormal DA receptor status is genetically determined or acquired after long-term alcohol consumption remains to be addressed.  相似文献   
7.
A human tumor xenograft (L56Br-X1) was established from a breast cancer axillary lymph node metastasis of a 53-year-old woman with a BRCA1 germ-line nonsense mutation (1806C>T; Q563X), and a cell line (L56Br-C1) was subsequently derived from the xenograft. The xenograft carries only the mutant BRCA1 allele and expresses mutant BRCA1 mRNA but no BRCA1 protein as determined by immunoprecipitation or Western blotting. The primary tumor, lymph node metastasis, and xenograft were hypodiploid by DNA flow cytometry, whereas the cell line displayed an aneuploidy apparently developed via polyploidization. Cytogenetic analysis, spectral karyotyping, and comparative genomic hybridization of the cell line revealed a highly complex karyotype with numerous unbalanced translocations. The xenograft and cell line had retained a somatic TP53 missense mutation (S215I) originating from the primary tumors, as well as a lack of immunohistochemically detectable expression of steroid hormone receptors, epidermal growth factor receptor, human epidermal growth factor receptor 2 (HER-2), and keratin 8. Global gene expression analysis by cDNA microarrays supported a correlation between the expression profiles of the primary tumor, lymph node metastasis, xenograft, and cell line. We conclude that L56Br-X1 and L56Br-C1 are useful model systems for studies of the pathogenesis and new therapeutic modalities of BRCA1-induced human breast cancer.  相似文献   
8.
Bladder motility recordings were performed in anaesthetized rats and the effect of the peripherally active opiate agonist loperamide on urinary bladder function was studied. Regional intra-arterial administration of loperamide (0.01-2 mg kg-1) induced weak bladder contraction per se. Loperamide caused an effective dose-dependent inhibition of bladder motility induced by regional injection of the receptor agonists acetylcholine (ACh) and substance P (SP), as well as by peripheral motor nerve stimulation (PNS). Pretreatment with naloxone (0.5 mg kg-1) partially antagonized the inhibitory action of loperamide on the nerve-mediated detrusor contraction. However, the depression of the motor responses induced by the receptor agonists ACh and SP was not influenced. It is suggested that the demonstrated inhibitory effect of loperamide on bladder motility is partially mediated by peripheral opioid receptors. The main non-opioid part of the inhibition might be a direct smooth muscle action.  相似文献   
9.
beta-Cell-rich pancreatic islets were incubated for 60-120 min in the presence of 1 mM or 20 mM glucose and analysed with regard to their contents of magnesium and calcium and how these elements were distributed among subcellular fractions. The islets contained 42 mmol magnesium per kg protein with as much as 70 mmol per kg protein in the microsomal fraction. Both the total amount and intracellular distribution of magnesium remained unaffected after raising the glucose concentration of the incubation medium. The islet content of calcium was twice as high as that of magnesium, the mitochondria and secretory granules accounting for most of the calcium in the sedimentable fractions. In both organelles a substantial fraction of calcium was exchangeable as indicated from the incorporation of 45Ca during 90 min of incubation of the islets. When raising the glucose concentration to 20 mM the percentage exchange of calcium increased from 10 to 27 in the mitochondria and from 13 to 28 in the secretory granules. The glucose stimulation of 45Ca uptake was not associated with a statistically significant increase in the total amounts of calcium. However, in addition to stimulating calcium/calcium exchange, it cannot be excluded that glucose also induces a net accumulation of intracellular calcium in the beta-cells.  相似文献   
10.
BACKGROUND: The natural history of genital human papillomavirus infection is well known, but nearly nothing is known about the outcome of oral HPV-infection. OBJECTIVES AND STUDY DESIGN: To study natural history of oral HPV in spouses during the follow-up 331 women (mean 25.5+/-3.4 years) and 131 men (mean 28.8+/-5.0 years) were recruited from maternity unit. Scrapings from healthy oral mucosa of spouses at baseline, 2, 6, 12 and 24 months and genital samples were taken for HPV testing. HPV DNA was detected by nested PCR and confirmed by hybridization using a cocktail of 12 high-risk (HR) oligoprobes. RESULTS: The detection rate of HR HPVs varied from 15% to 27%. Baseline oral HPV status between the spouses was closely related (odds ratio 4.3; 95% confidence interval 1.6-12.0; P=0.006). Persistent oral infection in one spouse was a significant risk factor (odds ratio 10.0; 95% confidence interval 1.5-68.7; P=0.005) for oral HR HPV persistence in the other partner. Cumulative incidence of new HR HPV infections was identical in both spouses, while men seemed to clear their infection more rapidly. In univariate survival analysis, the partner's oral or genital HPV status, oral sex habits or age did not predict clearance or acquisition of oral HR HPV. CONCLUSION: Natural history of HPV infection in oral mucosa mimics that of genital HPV infection. Oral sex had no association to oral HPV infection, but a persistent oral HPV infection of the spouse increased the risk of persistent oral HPV infection 10-fold in the other spouse.  相似文献   
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