AIM:To prospectively assess the sensitivity,specificity and time to positivity of theUltra-rapid urease test (URUT) for Helicobacter pylori(H pylori),and compare the results of one with those of two biopsies. METHODS:...AIM:To prospectively assess the sensitivity,specificity and time to positivity of theUltra-rapid urease test (URUT) for Helicobacter pylori(H pylori),and compare the results of one with those of two biopsies. METHODS:Five antral biopsies were taken in consecutive patients undergoing upper endoscopy:one and two biopsies for URUT,and one each for H pylori culture and histology. URUT was read at 1,5,10,20 and 30 min,1,2,3 and 24 h after biopsy insertion into the reagent.A positive histology and/or culture was used as positive reference“gold standards”. RESULTS:URUT was more sensitive for detecting Hpylori with two biopsies rather than one,at all time points up to 120 min.The sensitivity improved from 3.6% to 82.1% for one biopsy and 10.7% to 85.7% for two biopsies from 1 to 120 min.The sensitivity reached 96.4% at 24 h for both, but the specificity reduced from 100% to 96% and 92% for one and two biopsies,respectively. CONCLUSION:Development of a positive URUT result is hastened by doubling the number of gastric biopsies.We recommend taking two instead of one biopsy to achieve an earlier positive URUT result so that H pylori eradication therapy can be initiated before patient is discharged from the endoscopy suite.展开更多
An intrinsic sensor （diameter 16 ram, thickness 300 μm ） based on chemical vapor deposition derived polycrystailine diamond was developed. Ultra low dark current under 100 pA and high n/γ discrimination of 15.8 we...An intrinsic sensor （diameter 16 ram, thickness 300 μm ） based on chemical vapor deposition derived polycrystailine diamond was developed. Ultra low dark current under 100 pA and high n/γ discrimination of 15.8 were obtained on this device, which enable it to be used for neutron detection in multi-radiation field. Moreover, the neutron sensitivity of this detector was characterized theoretically and experimentally. And for fast and ultra-fast neutron, the detection sensitivity is in the magnitude of 10^-17 to 10^-16 C cm^2/n with good stability and negligible pump effect. All these results indicate that the as-prepared sensor to be ideal for fast and ultra-fast neutron monitoring, and it may pave the way to build neutron detector with low cost and large sensitive area with diamond.展开更多
文摘AIM:To prospectively assess the sensitivity,specificity and time to positivity of theUltra-rapid urease test (URUT) for Helicobacter pylori(H pylori),and compare the results of one with those of two biopsies. METHODS:Five antral biopsies were taken in consecutive patients undergoing upper endoscopy:one and two biopsies for URUT,and one each for H pylori culture and histology. URUT was read at 1,5,10,20 and 30 min,1,2,3 and 24 h after biopsy insertion into the reagent.A positive histology and/or culture was used as positive reference“gold standards”. RESULTS:URUT was more sensitive for detecting Hpylori with two biopsies rather than one,at all time points up to 120 min.The sensitivity improved from 3.6% to 82.1% for one biopsy and 10.7% to 85.7% for two biopsies from 1 to 120 min.The sensitivity reached 96.4% at 24 h for both, but the specificity reduced from 100% to 96% and 92% for one and two biopsies,respectively. CONCLUSION:Development of a positive URUT result is hastened by doubling the number of gastric biopsies.We recommend taking two instead of one biopsy to achieve an earlier positive URUT result so that H pylori eradication therapy can be initiated before patient is discharged from the endoscopy suite.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11175142,11175141 and 11105106)the National Hi-Tech Project of China (Grant No. 2009AA050705)the State Key Laboratory of Multiphase Flow (Xi’an Jiaotong University)
文摘An intrinsic sensor （diameter 16 ram, thickness 300 μm ） based on chemical vapor deposition derived polycrystailine diamond was developed. Ultra low dark current under 100 pA and high n/γ discrimination of 15.8 were obtained on this device, which enable it to be used for neutron detection in multi-radiation field. Moreover, the neutron sensitivity of this detector was characterized theoretically and experimentally. And for fast and ultra-fast neutron, the detection sensitivity is in the magnitude of 10^-17 to 10^-16 C cm^2/n with good stability and negligible pump effect. All these results indicate that the as-prepared sensor to be ideal for fast and ultra-fast neutron monitoring, and it may pave the way to build neutron detector with low cost and large sensitive area with diamond.
