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991.
A decided attitude of expectation among many patients has given a new perspective to regenerative and plastic periodonta surgery. With authors emphasizing on the importance of gingival thickness, attempts are being made to obtain necessary information atraumatically and rapidly. Hence in the present study an attempt has been made to compare the two methods of assessing gingival thickness i.e transgingival probing and ultrasonographic method and also assess the gingival thickness in relation to central incisor lateral incisor and canine in Indian population. The gingival thickness was assessed in patients with healthy gingiva by both the methods. It was observed that transgingival probing method significantly over estimated the thickness of gingiva than the ultrasonographic method and the thickness of gingiva varies with morphology of the crown. It was concluded that compared to transgingival probing ultrasonographic method assesses gingiva thickness more accurately, rapidly and atraumatically.  相似文献   
992.
993.
The appearance of an acute effusion in a well-pneumatized temporal bone directs attention to the nasopharynx and skull base. Two patients are described in whom dehiscence of the temporomandibular joint allowed herniation of the contents of the joint posteromedically, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors' knowledge, a previously unreported cause of an acute middle ear and mastoid effusion.  相似文献   
994.
D K Ziegler 《Neurology》1991,41(6):953-954
  相似文献   
995.
Kawasaki disease is now the most common cause of acquired heart disease in America's children. It is an acute febrile illness that may cause coronary artery aneurysm formation in infected children. The results of a multicenter, randomized trial on the effect of intravenous administration of gamma globulin (IVGG) plus aspirin versus aspirin alone upon coronary aneurysm formation show a decrease in coronary aneurysm formation from the usual 20%-30% to 3%. Administration of IVGG presents some unique challenges for nurses. Also, the pediatric nurse must educate parents and children about this disease to prepare them for discharge and long-term follow-up care.  相似文献   
996.
997.
We evaluated the efficacies of five treatment procedures for eliminating ascorbate interference in the enzymatic determination of urinary oxalate. Aliquots of urine samples, containing different amounts of added ascorbate and oxalate, were individually subjected to ferric chloride, sodium nitrite, sodium periodate, charcoal, or ascorbate oxidase treatment to eliminate ascorbate interference. Oxalate contents of the urine samples were then determined by a banana oxalate oxidase-horseradish peroxidase-linked assay with 3-methyl-2-benzothiazolinone hydrazone and 3-(dimethylamino)benzoic acid as chromogens. Only those urine samples treated with ascorbate oxidase or charcoal consistently gave recovery of oxalate close to 100%. Treatment with other reagents, though improving the recovery of oxalate, gave inconsistent results. On the basis of these data, we describe procedures for simply and reliably assaying oxalate by using banana oxalate oxidase.  相似文献   
998.
In many ways, MRI of the pediatric abdomen is in its infancy. Motion will be a problem with most of the current pulse sequences, but the problem appears manageable given many of the newer software options for motion suppression. Faster pulse sequences (approaching CT scan times) will serve to improve image quality and reduce the need for sedation. Identification of a reliable enteric contrast agent probably will expand the current utility of MRI beyond evaluation of solid abdominal viscera. Although preliminary results appear promising, controlled comparative studies are necessary to determine the exact role of MRI in diagnosis and staging of common pediatric abdominal malignancies. The addition of MRI intravenous contrast agents and MR spectroscopy are anticipated to add depth and specificity to the diagnostic potential of this exciting modality.  相似文献   
999.
1000.
Multiphase radon generation and transport in porous materials   总被引:5,自引:0,他引:5  
Radon generation and transport in porous materials involve solid, liquid, and gas phases in the processes of emanation, diffusion, advection, absorption, and adsorption. Oversimplifications, such as representing moist soil systems by air-phase emanation and transport models, cause theoretical inconsistencies and biases in resulting calculations. Detailed Rn rate balance equations for solid, liquid, and gas phases were analyzed and combined using phase equilibrium constants to derive a single diffusive-advective rate balance equation in the traditional form. The emanation, diffusion, and permeability coefficients in the new equation have expanded definitions and interpretations to include Rn phase transfer. Radon adsorption was characterized by an exponential moisture dependence, and diffusion and permeability constants utilized previous moisture relationships. Correct boundary and interface conditions were defined, and the unified theoretical approach was applied to field data from a diffusion-dominated system and to laboratory data from an advection-dominated system. Measured 222Rn fluxes and concentrations validated the modeled values within the measurement variability in both applications.  相似文献   
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