Objective To establish and evaluate a method for determination of total arsenic in urine by test-tube rapid digestion hydride generation atomic fluorescence spectrometry.Methods After digestion of urine samples using graduated test-tube and graphite digestion apparatus,arsenic content in urine was determined with atomic fluorescence spectrometer.Then the test results were evaluated by using quality control measures,such as precision and accuracy experiments,and the results between different laboratories were reviewed and compared.Results The urinary arsenic was in a linear range of 0-0.300 mg/L,correlation coefficient (r) ＞ 0.999 3,detection limit was 0.000 21 mg/L,relative standard deviation (RSD) ≤4.62％ and the recoveries of standard addition were 93.9％-104.3％.The value of standard reference material measured was within the allowable range.The blind sample of the national urinary arsenic was qualified.Conclusions This method is suitable for large scale determination of urinary arsenic for its micro sample amount needed,less interference and strong practicability.The error results are in a controlled range.

OBJECTIVE: To explore the expression and significance of Eotaxin and RANTES in the rat model of allergic rhinitis (AR). METHOD: 20 female SD rats in 6-7 weeks were randomly divided into control group and AR group (n = 10, respectively). AR rat model was made with ovalbumin stimulation. To detect pathological changes in mucosa and chemokine Eotaxin, RANTES in their nasal and lung tissues after execution. RESULT: Compared with the control group, Lung EOS cell counted higher in AR group and the difference was significant (P < 0.01); the AR rats nasal mucosa and lung tissue of Eotaxin, RANTES expression was significantly increased (P < 0.01). CONCLUSION There exist high expression of Eotaxin, RANTES, infiltration of eosinophils in nasal and lung tissue of model rats with allergic rhinitis, inferring that the upper and lower respiratory tract inflammatory response has obvious consistency.
Animals ; Chemokine CCL11 ; metabolism ; Chemokine CCL5 ; metabolism ; Disease Models, Animal ; Female ; Lung ; metabolism ; Nasal Mucosa ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic ; metabolism

OBJECTIVETo examine the effect of the location and diameter of implants on stress distribution in three-unit implant-supported posterior cantilever fixed partial dentures (FPD) in the mandible.

METHODSA three-dimensional finite element model was developed to represent a rigid implant-supported posterior FPD that restores the second left premolar, first molar, and second molar. The location of the distal implant with a diameter of 4.8 mm remained the same, whereas the mesial implants with diameters of 4.1 and 4.8 mm were successively moved toward the posterior area with distances of 5.5, 8.0, 10.5, and 13.0 mm from the long axis of the mesial implants to the first premolar to form the cantilever FPD. Dynamic loads of 250 N were applied from different directions on the buccal and lingual cusps of the FPD to simulate the masticatory cycle for 0.875 s. The maximum Von Mises stresses were calculated using the finite element analysis software MSC. Marc and Partran.

RESULTSThe maximum Von Mises stresses of the mesial and distal implants increased to some extent as the mesial implants moved toward the posterior area. Significant increases in the maximum Von Mises stresses were obtained when the mesial implants were located more than 8.0 mm posterior to the first premolar, and moderate increases in the stresses were observed when the mesial implants were located less than 8.0 mm posterior to the first premolar. The use of a broader implant reduced the stress on the interface between the bone and the implants. The maximum Von Mises stresses were found in the cervical region of the cortical bone adjacent to the mesial or the distal implants during stages II to IV of the masticatory cycle. Off-axial loading induced more stresses compared with vertical loading.

CONCLUSIONThe location of implants in three-unit implant-supported posterior cantilever FPD is a significant factor that influences the stress generated in the interface between the bone and the implants. An implant-supported cantilever FPD is a feasible option for restoring missing teeth when the length of the cantilever is not greater than the width of a premolar. Two important factors should be considered before choosing the implant diameter, namely, bone volume and cantilever length.

Bicuspid ; Dental Implants ; Dental Prosthesis, Implant-Supported ; Denture, Partial, Fixed ; Finite Element Analysis ; Humans ; Mandible ; Stress, Mechanical

Respiratory diseases are common， frequently-occurring clinical diseases. As the prevalence rate is increasing year by year， they have become a problem that seriously affects public health. The diseases are mainly located in the lung by traditional Chinese medicine （TCM） syndrome differentiation. Lung governs Qi and controls breathing and is also an organ for the storage of phlegm. Clinically， phlegm and Qi are often used for the treatment. Banxia Houputang （BHT）， originated from Synopsis of the Golden Chamber （《金匮要略》）， was used to treat plum-stone Ai （globus hystericus） at first. It is composed of Rhizoma Pinelliae， Cortex Magnoliae Offcinalis， Poria， Rhizoma Zingiberis Recens， and Folium Perillae， and treats diseases with the core pathogensis of mutual obstruction of phlegm and Qi. BHT has the effects of moving Qi， dissipating mass， descending adverse Qi， and resolving phlegm， which basically correspond to the pathological characteristics of the lungs. Clinical studies have confirmed that modified BHT can be used either alone or in combination with western medicine to treat chronic pharyngitis， asthma， chronic obstructive pulmonary disease， pneumonia， obstructive sleep apnea， upper airway cough syndrome and other respiratory diseases， with significant effects. It effectively improves the symptoms and signs of the diseases and reduces the recurrence rate. Basic research has shown that BHT plays anti-inflammatory， anti-oxidative stress， anti-apoptotic， autophagy-regulating， and iron overload-regulating roles by regulating the targets in multiple pathways. This paper， by combing the relevant literature in recent years， conducted a systematic review on BHT from the three aspects of syndrome analysis， clinical treatment research and mechanism research， with a view to providing theoretical basis and reference for the mechanism research of BHT in treating respiratory diseases and for expanding its clinical application.