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1.
OBJECTIVE: The aim of the current study was to test the impact of dentin powder on the antimicrobial efficacy of bioactive glass S53P4 (BAG). STUDY DESIGN: BAG was suspended (preincubated) in saline at 37 degrees C for different time periods with or without human dentin powder, hydroxylapatite, or decalcified dentin. Subsequently, Enterococcus faecalis ATCC 29212 cells were added to these suspensions and bacterial recovery measured with and without the use of gentle sonication. Furthermore, survival of bacteria in test and control suspensions was assessed over time. Supernatants of suspensions were analyzed for their element contents using atomic absorption spectrophotometry. The effects of pH, silica, and osmolarity on E faecalis viability were assessed using specifically prepared solutions. RESULTS: BAG preincubated with dentin powder caused a significant (P < .05) decrease in viability compared to pure BAG suspensions. This was not based on adherence of bacteria to solid particles or agglutination of the cells, because sonication did not increase bacterial yields. Hydroxylapatite and decalcified dentin did not increase BAG killing efficacy. The additive effect of BAG + dentin powder was dose dependent, occurred only with solids in suspension, and increased with suspension time. An augmented dissolution of glass components, especially silicon, was measured in BAG + dentin powder compared to pure BAG suspensions or counterparts containing hydroxylapatite or decalcified dentin. High osmolarity per se did not affect E faecalis viability, whereas high pH and silica levels did. CONCLUSION: The observed phenomenon was related to an increased BAG dissolution triggered by dentin powder, causing elevated local pH and silica levels.  相似文献   
2.
A study of the angiographic findings in consecutive civilian patients with cranial gunshot wounds examined in the acute stage has not been done. Most prior clinical studies have evaluated the findings in survivors in the subacute or chronic stages and have often been of war-time casualties. We determined the clinicoradiologic features of six cases of posttraumatic intracranial aneurysm, vascular occlusion, or arteriovenous fistula caused by penetrating missiles among 12 civilian patients who were examined in the acute posttraumatic stage (within 48 hr of injury) during a 1-year period. Three internal carotid/vertebral artery aneurysms, one external carotid artery aneurysm, one combined aneurysm/arteriovenous fistula of the vertebrobasilar circulation, and one cerebral venous occlusion were identified. The 50% overall prevalence of major vascular lesions in this series of civilian patients with penetrating missile injuries examined in the acute stage suggests these injuries are more common than previously suspected. It may indicate that selective cerebral angiography should be considered in the evaluation of the cranial vascular system of such persons.  相似文献   
3.
We report an unusual case of an enterovesical fistula secondary to adenocarcinoma of the appendix.  相似文献   
4.
Renal pelvic carcinoma is a rare tumor. There are several staging systems currently in use based on a bladder cancer staging model. An analysis of the American Cancer Society, Illinois Division, experience with 611 cases of renal pelvic transitional cell carcinoma suggested that the kidney parenchyma may be a determinant in the anatomic spread of disease. A tumor-node-metastasis system for renal pelvic (separate from ureteral) cancer is recommended.  相似文献   
5.
Whistling face syndrome or cranio-carpotarsal dysplasia is a very rare disorder that consists of a characteristics facies and digital abnormalities. Magnetic resonance imaging investigation of the brain in this syndrome has not been reported previously. This communication describes the brain malformations in an infant with the syndrome, which covered delayed myelination, thickened and infolded cortices (cortical dysplasia), dysplastic corpus callosum, and agenesis of the inferior vermis.  相似文献   
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7.
A new triterpenoidal saponin having hederagenin as the aglycone was isolated from the roots of SYMPHYTUM OFFICINALE L. The structure of this saponin was elucidated by FAB-MS, (1)H-, (13)C-NMR, 2D-NMR analyses and chemical studies as 3- O-[beta- D-glucopyranosyl-(1-->4)-alpha- L-arabinopyranosyl]-hederagenin 28- O-[beta- D-glucopyranosyl-(1-->6)-beta- D-glucopyranosyl] ester.  相似文献   
8.
Three adult patients are reported with asymptomatic localized widening of the central canal of the spinal cord. These patients were followed for a period of 24 years by imaging and/or clinical history and physical examination without evidence of signs or symptoms related to the spinal cord. This condition probably represents persistence into adult life of a fetal configuration of the central canal of the spinal cord. This process may be termed "idiopathic localized hydromyelia" to distinguish it from syringomyelia secondary to such causes as Chiari malformation, trauma, infection, or neoplasm.  相似文献   
9.
Purpose: To evaluate the effects of topical timolol and apraclonidine on retrobulbar blood flow velocity waveforms in a group of healthy volunteers.Methods: Apraclonidine 1% and timolol maleate 0.5% single dose administrations were crossed over double masked in 12 healthy volunteers. The intraocular pressure measurements were followed by Doppler examination of the ophthalmic artery and the central retinal artery.Results: Intraocular pressure was reduced significantly on both treated and fellow eyes after timolol (p = 0.003, p = 0.04 respectively) and after apraclonidine (p = 0.002, p = 0.01 respectively). After apraclonidine administration end diastolic velocity, mean velocity decreased and pulsatility index increased in the ophthalmic artery of both treated and fellow eyes. Resistivity index increased and peak systolic velocity decreased only in the ophthalmic artery of treated eyes. All Doppler indices remained nonsignificant for central retinal artery of both eyes.After timolol administration there were no significant changes of the Doppler indices in the ophthalmic artery and central retinal artery of the treated and fellow eyes.Conclusion: Topical timolol and apraclonidine significantly reduced the intraocular pressure. Single dose administration of apraclonidine 1% increased the vascular impedance distal to the ophthalmic artery. On the other hand, timolol 0.5% had no effect on vascular impedance.  相似文献   
10.
We investigated the severity and the quality of pain in the end-plate and the electrically silent site during electromyography by self-assessment. In 42 muscles of 30 patients, the mean pain score was 52.0 +/- 5.3 of 100 for the end-plate region, and it was 27.7 +/- 4.8 for the silent site. The commonest type of pain was pricking both in the end-plate region and the silent site (19 and 31%, respectively). We suggest two hypotheses for the difference. The pain fibers may be more densely situated in the end-plate, or muscle fiber contraction precipitated by needle irritation may also cause irritation of pain fibers.  相似文献   
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