Objective To design a new X-ray sensor of iono-chamber type to achieve automatic exposure control(AEC) of the X-ray machine. Methods We designed the chamber acording to the ionization theory and the requirements of automatic exposure control. Results (1) The device had double-negative poles, so the distance between positive and negative poles was 1/2 shorter and its test-volume was equal to odd-negative pole. (2)It had good property of electromagnetism-resistance because of the double shielded design by double-negative poles and screen-rings.(3) Iono-chamber was made of low-density material, so it had low absorb-ratio of X-ray and could not form image on film. Conclusion The property of the device was steady and reliable. It had applying and spreading value.

Objective To design an automatic exposure control circuit for X ray equipment to improve the performance of equipment and the quality of film. Methods The device acted in series control. During exposuring process,the X ray reaching the film through patient body was measured by ray sensor. After it was treated with integration, amplification and contrast management,the signal of X ray quantity drived the device to cut off exposure circuit, so that the exposure time was automatic any controlled. Results The effect of the device has been proved by its application in several hospitals. Conclusion The device is simple and effective and has practical value.

BACKGROUND:In the process of cardiac stem cel culture in vitro, the growth microenvironment may have some effects on the cel proliferation.
OBJECTIVE:To investigate the possible mechanism of proliferation and migration of rat cardiac stem cel s cultured in vitro.
METHODS:Cardiac tissues from 10 Sprague-Dawley rats were obtained for primary culture and subculture. Passage 3 cel s were col ected for immunofluorescence staining, and stem cel growth factor receptor (c-kit) and CD45, CD90 were detected. Cultured tissues were col ected and randomly divided into two groups:in group 1, paraformaldehyde fixation, paraffin embedding, hematoxylin-eosin staining, Masson staining, and detecting apoptotic cel s using TUNEL method were conducted;in group 2, EdU labeling of proliferated cel s, immunofluorescent detection of c-kit positive expression, matrix metal oproteinases 2, 9 and transforming growth factorβ1 using immunofluorescent staining were done.
RESULTS AND CONCLUSION:After 7-10 days of myocardial tissue culture, bright and round cel s were visible, and after adhesion, fusiform cel s exhibited strong growth and proliferation ability. Immunofluorescence staining showed a large number of c-kit, CD45 positive cel s but CD90 negative cel s. After culture, a great number of newborn cel s were found, accompanied by apoptosis of myocardial cel s. After EdU staining, the positive cel s were distributed in the myocardial gap, and showed a smal amount of matrix metal oproteinases 2, 9 and transforming growth factorβ1, while in the surrounding myocardium there was a large number of matrix metal oproteinases 2, 9 and transforming growth factorβ1. Taken together, our findings show that cardiac stem cel s could be obtained through myocardial tissue culture in vitro, accompanied by cel proliferation and migration. The mechanism is related to the expression of matrix metal oproteinases 2, 9 and transforming growth factorβ1.

Objective: Describe the depressive symptoms and suicidal characteristics of patients with major depressive episodes treated in non-psychiatric outpatient and inpatient departments of general hospitals. Methods: Trained psychiatric nurses administered our depression screening instrument to 2 877 consecutive outpatients and 2 925 inpatients who were at least 15 years of age, able to complete the survey and had no serious communication difficulties. These subjects were identified from 35 level-1, 8 level-2, and 7 level-3 general hospitals in Beijing that were selected by stratified random sampling. Results:Compared to 5 604 patients without depression, a higher proportion of the 198 patients with major depressive episode were agricultural laborers (14.2% v. 7.9%, ?2=17.48), uninsured (45.2% v. 37.8%, ?2=4.41), inpatients (63.1% v. 50.0%, ?2=13.26), treated in internal medicine departments (the internal medicine, surgical, genecological, traditional Chinese medicine and other medical departments distribution of depressed versus non-depressed patients was 51.5%, 30.8%, 3.0%, 2.5%, and 12.1% v. 40.7%, 30.5%, 9.8%, 4.9%, and 14.0%, ?2=17.28), less educated [9(4) v. 10(5) years of formal education, t=-3.55] and relatively poor (median monthly per capita income in the family was 500 yuan v. 800 yuan, Z=-4.86) (all P

Objective To evaluate the efficacy and safety of Sun's tip-flexible ureterorenoscopy (tf-URS) combined with holmium laser lithotripsy in treatment of renal and upper ureteral calculi.MethodsClinical data of 48 patients (29 males and 19 females) with renal and upper ureteral calculi treated by tf-URS with holmium laser lithotripsy in our hospital from November 2015 to May 2016 were retrospectively analyzed.Among 48 patients there were 29 males and 19 females with a mean age of (37.8±12.5) years (21-67), including 31 cases of upper ureteral calculi and 17 cases of renal calculi with a mean stone size of (1.4±0.6) cm (0.8-2.1).The tf-URS was advanced through the ureter under visual direction with rigid mode.When the endoscope reached the ueteropelvic junction, the inner flexible part was extended out to explore the pelvicaliceal stones and then the holmium laser lithotripsy was performed.The therapeutic results were evaluated by KUB 2 days after operation and color ultrasonography or CT 4 weeks after operation.Results The success rate of insertion of tf-URS was 94% (45/48).The calculi were detected in 45 cases, and laser lithotripsy succeeded in 43 cases (96%).The rate of total stone clearance was 87% (39/45).The procedure was transformed to laparoscopic or percutaneous nephrolithotomy (PCNL) in 3 patients with ureterostenosis or ureteral distortion.No serious complications occurred.Conclusion The tf-URS with holmium laser in the treatment of renal and upper ureteral calculi is safe,reliable and effective.

Objective To study the influence of CRT brightness on image reading. Methods Both physical testing and compared viewing were used in the study. (1) Setting the CRT brightness at high and low grade (the blank brightness of CRT was 112 cd/m 2 and 82 cd/m 2, respectively). (2) 21 films with the density ranging from 0.27 to 2.71 were digitized by a scanner and displayed on the CRT. The brightness of CRT that varied with film density was measured by a bright meter, then the relation chart between CRT brightness and the film density was drawn. (3) Thirteen films on which there were many small and low contrast signals were viewed on CRT by three doctors. The tested data were calculated by statistics (? 2 test, the difference was significantly marked when P 0.05), but the signals viewed in the lung were 87 and 29, and the difference was significantly marked (? 2=53.73, P

OBJECTIVE To optimize the cleaning method of uterine cavity aspiration tube,compare with traditional method,in order to search the best way to improve the cleaning quality. METHODS Two groups A and B were set up according to the cleaning method and procedure. Group A (scrubbing group) was washed by optimized method,namely multi-enzyme soaking,scrubbing the lumen with special brush,rinsing with high pressure spray gun,and ultrasonic multi-enzyme cleaning. Group B (no scrubbing group) was used by traditional cleaning method;the cleaning procedure of Group B was almost the same with group A but had no lumen scrubbing. Both eyeballing and bacterial detection methods were used to compare cleaning quality of the two groups.RESULTS After cleaning procedure,the cleanliness pass rate of groups A and B was 99.52% and 56.25%,respectively (P

Objective To compare and analyze the performance indexes and the imaging quality of the home and imported X-ray machines through testing their partial imaging performance parameters. Methods By separate sampling from 10 home and 10 imported X-ray machines, the parameters including tube current, time of exposure, machine total exposure, and repeatability were tested, and the imaging performance was evaluated according to the national standard. Results All the performance indexes met the standard of GB4505-84. The first sampling tests showed the maximum changing coefficient of imaging performance repeatability of the home X-ray machines was ?max1=0.025,while that of the imported X-ray machine was ?max1=0.016. In the second sampling tests, the maximum changing coefficients of the two were ?max2=0.048 and ?max2=0.022, respectively. Conclusion The 2 years′ follow-up tests indicate that there is no significant difference between the above-mentioned parameters of the elaborately adjusted home X-ray machines and imported ones, but the home X-ray machines are no better than the imported X-ray machines in stability and consistency.

Objective:To understand the characteristics of the callers with the diagnosis of mental disorders called Beijing Psychological Crisis Hotline for help,in order to provide specific psychological intervention services for them in future.Methods:From December 2002 to December 2008,24217 different callers'data collected from a computer-based operating system of the Beijing Psychological Crisis Hotline were analyzed.According to their self-reported of having the diagnoses of mental disorder or not,the callers were divided into the ones with diagnosis (n=6516)and the ones without diagnosis (n =17701).The callers'demographic characteristics,their main counseling problems and the suicide-related factors in the two groups were compared.Results:The top five main counseling problems in the group with diagnosis were mental problems,the mental illness related knowledge,the problems of family relationships,working problems and interpersonal problems.Mental problem ranked first in both groups.Compared to the group without diagnosis,the diagnosed ones were more likely to be found in such group of people as women,aged between 20 -29 and 30 -44,having 10 or more years of education and the unem-ployed.The results of the assessments of 11 suicide-related risk factors showed that callers with diagnoses had higher prevalence of most suicide-related factors than those in the other group(P <0.001 or 0.05),which included suicidal intention and behavior while calling,history of attempted suicide,severe depressive symptoms,severe physi-cal illness,history of being abused,afraid of being attacked,suicidal history of relatives or associates,severe of hopeless.Conclusion:The hotline counselors should be aware of the necessity of assessing the severity of depres-sion and other suicide-related factors for the callers with mental disorder diagnoses before providing any psychologi-cal intervention.Moreover,except for providing interventions on the callers'psychiatric problems,the hotline coun-selors should also identify and help to deal with the stress events in their lives.

Objective:To develop the Counseling Skills Rating Scale for Psychological Aids Hotline (CSRSPAH),an instrument to objectively assess the quality of process of counseling or intervention provided by hotline operators,and to test its validities and reliabilities.Methods:A draft of the scale,which consisted of 50 items under 5 dimensions,was designed in line with previous researches and the practice.In pilot study,supervisors at Beijing psychological aids hotline,assessed tape recorded sessions and gave feedbacks on the draft of the scale.The scale had been revised based on the pilot study.Twenty-eight items were deleted,and several items were rephrased.Finally,a scale which consisted of 22 items within 3 dimensions,i.e.counseling process,attitude,and communication skill,was developed.The scoring standards of the scale were also developed.To evaluate the IntraClass Coefficients (ICC) of the CSRSPAH,each of the tape records of 37 callings from 2005 to 2007 were assessed by 7 supervisors independently,using the scale.And the tape records of other 318 callings from 2013 to 2014 were also assessed by supervisors,using the CSRSPAH.The results of the 318 assessed callings were used to test the construct validities with the Confirmative Factor Analysis.The Cronbach a coefficients of the total score and three dimensions,the discriminant indices of every items,and correlations of each items and each dimensions were calculated,based on the 318 assessed callings.Results:One of the items (referral) was deleted due to excessive amount of missing data.Results of cortfirmative factor analysis of the remained 21-item scale revealed that the 3-factor construct structure of the scale was robust.The fitting indices of the confirm factor analysis were,x2/df=675.21/186,CFI =0.92,NNFI =0.91,RMSEA =0.10,SRMR =0.08.The Cronbach α coefficients of the total score,scores of counseling process,attitude,and communication skill,were 0.89,0.68,0.81 and 0.77,respectively.The ICCs of the inter-rater reliabilities of the total score and 3 dimensions of the scale were 0.67,0.59,0.59,and 0.67,respectively.The discriminant indices of all the 21 items ranged from 0.09 to 0.32.The correlation coefficients of scores of each items and scores of 3 dimensions and total scores were greater than 0.30,and reached statistical significance.Conclusion:The validities and reliabilities of the Counseling Skills Rating Scale for Psychological Aids Hotline are acceptable.The scale could be used in assessing the quality of hotline counseling or intervention,and related studies in the future.