Objective To optimize the exposure parameters and reduce the irradiation dose level in infants and young children during digital radiography (DR) chest radiography under the premise of satisfied image quality.Methods The thoracic thickness of 100 patients were measured.Determined the aluminum equivalent of the thoraxes of the infants and young children by comparing the grayscale value and the aluminum step wedge.Another 100 infants and young children of experimental exposure were performed with the aluminum step wedge as a phantom,under AEC control,kV was the only variant to explore the optimal exposure parameters with dose monitor simultaneously.At last,clinical validation was performed.Images quality was compared with x2 test.The radiation dose of two groups was compared with t test.Results The maximum,minimum,average thoracic thickness and their correspondent aluminum equivalent were 13.5 and 2.3 cm,8.0 and 1.4 cm,(10.6 ± 1.3) and 2.0 cm,respectively.The average thoracic thickness of experimental group was (10.1 ± 2.2) cm.The range of entrance surface dose was 0.068-0.056 mGy while the tube voltage range was 55-65 kV.The exposure index range was 0.60-0.74.The visual inspection of aluminum step wedge was from grades 8 to 11 with satisfying image quality at lower radiation.The infant chest X-ray photography exposure parameters formula have been optimized,that was kV =thoracic thickness (cm) × 2 + 38 (constant),mAs (0.8-1.0) with SID =100 cm,without filter grid.Compare to the conventional parameters,the image quality of new method had no significant differences (P ＞ 0.05).The actual average entrance surface dose was (0.048 ± 0.007) mGy,lower than AEC group (0.066 ± 0.008) mGy.The difference was statistically significant (t =16.781,P ＜ 0.001).Conclusions The optimized formula kV =thoracic thickness (cm) ×2 + 38(constant),mAs (0.8-1.0) with SID =100 cm was credible for lowering the radiation exposure with good image quality for clinical diagnosis.

Objective:To Investigate a simple, economical and efficient method of primary osteoblast culture and compare their characteristics. Methods:Primary osteoblasts of 1 st -4 th series explant culture from calvarial bones of neonatal Sprague Dawley rats,were collected and osteoblasts shape, mitosis, proliferation, ALP activity and immunohistological expression of osteocalcin and BMP 2 observed. Results:No difference was found in cell shape, spread, conflunce, ALP activity as well as immunohistological stain of osteocalcin and BMP 2 of the osteoblasts, which had been harvested from the 1 st -4 th series explant cultures of Sprague Dawley rats. Conclusion:Series explant culture can harvest the same kind of osteoblasts as the explant culture, and more osteoblasts can be obtained at a single time. It saves money and time and is easy to manipulate.

ObjectiveTo explore the possible mechanisms of electroacupuncture at Fengchi （GB 20）， Waiguan （TE 5）， and Yanglingquan （GB 34） in treating chronic migraine from the perspective of nociceptive sensitization. MethodsForty SPF-grade SD rats were randomly divided into blank group， model group， electroacupuncture group， electroacupuncture + agonist group， and inhibitor group， with 8 rats in each group. Except for the blank group， rats were injected intraperitoneally with nitroglycerin to establish a chronic migraine rat model. After successful modeling， the electroacupuncture group received electroacupuncture at bilateral "Fengchi" （GB 20）， "Waiguan" （TE 5）， and "Yanglingquan" （GB 34） for 30 minutes each session. The electroacupuncture + agonist group received the same electroacupuncture treatment and additional injection of protein kinase C （PKC） agonist Phorbol 12-myristate 13-acetate （1.0 ng/μl， 25 μl） via the infraorbital foramen. The inhibitor group received PKC inhibitor Chelerythrine Chloride （1.0 ng/μl， 10 μl） via the infraorbital foramen. The blank group， model group， and inhibitor group underwent restraint for 30 minutes without other interventions. All groups were continuously intervened for 5 days. After the intervention， the nociceptive thresholds （mechanical and thermal pain） of the periorbital area and hind paw were measured. The expression levels of transient receptor potential vanillic acid subtype 1 （TRPV1）， phosphorylated TRPV1 （p-TRPV1）， PKC proteins， Trpv1， Pkc mRNA， and the average fluorescence intensity of transient receptor potential vanillic acid subtype 1 （TRPV1） and PKC in the trigeminal ganglion were detected using Western Blot， real-time fluorescence quantitative PCR， and immunofluorescence methods. ResultsCompared with the blank group， the mechanical and thermal pain thresholds of the periorbital area and hind paw were reduced in the model group， and the protein levels of TRPV1， PKC， p-TRPV1， as well as the mRNA expression of Trpv1 and Pkc， and the average fluorescence intensity of TRPV1 and PKC in the trigeminal ganglion significantly increased （P＜0.05 or P＜0.01）. Compared with the model group， the electroacupuncture group exhibited increased mechanical and thermal pain thresholds in the periorbital and hind paw areas， and decreased protein levels of TRPV1， PKC， p-TRPV1， mRNA expression of Trpv1 and Pkc， and average fluorescence intensity of TRPV1. In the electroacupuncture + agonist group， the average fluorescence intensity of TRPV1 in the trigeminal ganglion decreased. The inhibitor group exhibited increased mechanical pain thresholds in the periorbital area and thermal pain thresholds in the hind paw， along with decreased protein levels of TRPV1， PKC， p-TRPV1， and the average fluorescence intensity of TRPV1 and PKC （P＜0.05 or P＜0.01）. Compared with the electroacupuncture group， the electroacupuncture + agonist group showed an increase in the protein levels of TRPV1， PKC， p-TRPV1， and the mRNA expression of Trpv1 （P＜0.05 or P＜0.01）. ConclusionElectroacupuncture at the "Fengchi" （GB 20）， "Waiguan" （TE 5）， and "Yanglingquan" （GB 34） acupoints can increase the mechanical and thermal pain thresholds in chronic migraine rats and alleviate nociceptive sensitization. The mechanism may be related to the inhibition of PKC/TRPV1 pathway.

Antibodies, Antinuclear ; Autoantibodies ; China ; Cohort Studies ; Humans ; Scleroderma, Systemic