It is inevitably that any medical laboratory instrument may have trouble during its operation no matter how advanced it is.The only difference is the failure rate of each medical laboratory instrument.So in order to ensure these instruments work normally,it is very important to maintain them correctly.This paper gives an introduction of characteristics and maintenance requirements about medical laboratory instruments.

Objective To identify the spatial distribution of stray radiation from mobile CT head scanning for the purpose of radiation protection.Methods The head series of CareTom mobile CT were scanned and the radiation dose was measured using TLD (LiF:Mg,Cu,P).The isodose maps of radiation dose field were plotted using Matlab software.Results Radiation dose in the front of the mobile CT was slightly higher than that in the back.The maximum value of 0.255 mGy was found to be at 0.5 m from the scanning hole center.Conclusions The stray radiation dose from mobile CT head scanning was relatively low.However in order to avoid the damage to the operators and other medical workers from long-term low dose exposure,it should keep 2 m away from mobile CT,beside or behind,when in operation.

Objective To investigate the feasibility and clinical value of anteroposterior and lateral scout scan combined with Care Dose 4D and Care kV in chest CT scan.Methods A total of 60 patients of clinical diagnosis with lung tumor were enrolled.Those patients were randomly divided into test group and control group.Control group underwent a scan protocol with lateral scout scan combined with Care Dose 4D and Care kV,while anteroposterior and lateral scout scan combined with Care Dose 4D and Care kV were performed in test group.The signal-to-noise ration (SNR),contrast-to-noise ratio (CNR),and overall image quality of two groups of images and diseased tissues were analyzed and evaluated by two high-grade radiologists using double-blind method.Effective doses (E) were also calculated.Results All the 60 patients had successfully completed the chest CT scans.Test group overall image quality (4.57 ± 0.45) and control group overall image quality (4.73 ± 0.45) had no statistically significant difference (P ＞ 0.05).The control group image SNR,CNR and diseased tissue SNR,CNR compared with test group had no statistical significance difference (P ＞ 0.05).The difference of the volume CT dose index (CTDIvol),dose-length product (DLP) and effective dose (E) of test group and control group was statistically significant (t =8.514,8.464,8.464,P ＜ 0.001).Compared with control group,the effective dose of test group decreased by 33.3％.Conclusions Compared with lateral scout scan,the technology of anteroposterior and lateral scout scan combined with Care Dose 4D and Care kV can decrease radiation dose without reducing the image quality.This technology can therefore be considered as a regular imaging modality for chest CT scan.

Objective: To understand the cardiopulmonary endurance status of Tibetan middle school students in different high altitude areas and the relationship with body mass index (BMI), and to provide reference for cardiopulmonary endurance improvement among students in different high altitude areas. Methods: From October to November 2019, 3 819 Tibetan middle school students in Linzhi, Lhasa, and Nagqu Regions of Tibet were tested with the 1 000meter run for boys and 800 meter run for girls, and BMI was calculated. The cardiorespiratory endurance of middle school students in different high altitude areas was compared, the detection rate of wasting, normal, overweight and obesity was compared with the χ 2 test, and the relationship between body mass index and cardiorespiratory endurance was analyzed by multiple linear stepwise regression. Results: The differences in VO 2max between Tibetan middle school students aged 13-15 and 17-18 years in Nyingchi, Lhasa and Nagqu were statistically significant( F=26.72, 13.75, 23.86, 8.68, 9.35, P <0.01), and 13-14, 16-18 years old girls in three regions with VO 2max ( F=5.29, 4.36, 11.38 , 7.79, 16.30，P <0.01). The proportion of boys wasting in Linzhi area was 10.2%, that of Lhasa area was 8.7%, and that of Nagqu area was 17.5%, the difference was statistically significant( χ 2=25.91, P <0.01); the proportion of girls wasting, Linzhi, Lhasa, and Nagqu were 2.6%, 2.5%, 5.1%, the difference was also statistically significant( χ 2= 8.35 , P <0.05). Multiple linear stepwise regression analysis showed that after body mass index and altitude included, the model △ R 2=0.075, and Tibetan middle school students were overweight and obese ( B=0.44, 95%CI =0.39-0.49) and positively correlated with VO 2max ( P <0.01); weight loss ( B=-0.36, 95%CI =-0.42--0.29) was negatively correlated with VO 2max ( P <0.01); altitude [Lhasa Area： B(95% CI )= -0.44(-0.49--0.39)，Nagqu Region： B(95%CI )=-0.51(-0.56--0.45)] was negatively correlated with VO 2max ( P <0.01). Conclusion Overweight and obesity are positively correlated with VO 2max , and weight loss and altitude are negatively correlated with VO 2max . The proportion of wasting among Tibetan middle school students in high altitude areas needs to be focused for cardiorespiratory endurance improvement.

OBJECTIVETo investigate the chemical constituents of the extract of Galium verum.

METHODThe compounds were isolated by chromatography and identified by spectral data.

RESULTThe eleven compounds obtained were identified as (+)-pinoresinol 4,4'-O-bis-beta-D-glucopyranoside (1), epipinoresinol (2), (+) -medioresinol (3), isorhamnetin (4), isorhamnetin 3-O-alpha-L-rhamnopyranosyl-(1-6)-beta-D-glucopyranoside (5), diosmetin (6), diosmetin 7-O-beta-D-glucopyranoside (7), quercetin-3-O-beta-D-glucopyranoside (8), ursolic acid (9), ursolic aldehyde (10) and rubifolic acid (11).

CONCLUSIONCompounds 1-5 and 9-11 were isolated from this genus for the first time.

Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Galium ; chemistry

OBJECTIVETo investigate the effects of the solid-state fermentation technology in extracting the ingredients of traditional Chinese medicine (TCM).

METHODUsing Danggui Kushen pills as an example, four index ingredients of ferulic acid, matrine, matrine alkaloids and dry extract were compared comprehensively, and the difference between the two water extractions of fermented pills and unfermented pills was evalued.

RESULTThe comprehensive evaluated result was that extraction of fermented pills was better than that unfermented.

CONCLUSIONThe solid-state fermentation is conducive to the extraction of prescription of Danggui Kushen pills.

Chemical Fractionation ; methods ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; metabolism ; Fermentation ; Reproducibility of Results ; Water ; chemistry

Objective To evaluate the therapeutic effect with peter-williams intramedullary nail on children with humerus deformity due to osteogenesis imperfecta.Methods Data of 9 patients with humerus deformity due to osteogenesis imperfecta were retrospectively analyzed from Jun.2009 to Dec.2012.There were 7 males and 2 females,aged from 6 years to 10 years and 7 months(average 8 years and 3 months).There were 7 unilateral humerus deformity and 2 bilateral humerus deformity with severe radius and ulna deformity.The humerus fracture frequency was from 4 to 13 times (average,7.9 times)There were 2-3 deformity points in 9 patients (average 2.09 deformity points).The deformity angle ranged from 20°-100° (average 57.3°).The Constant-Murley scores were 16-24 scores (average 20.44).According to revised Sillence classifications,there were 6 cases of Type Ⅲ and 3 cases of Type Ⅳ.Eleven humerus of 9 patients were osteotomied and fixed with peter-williams intramedullary nail.Results All of 9 children were followed up for 12-66 months(average 22 months).The bone healing time were 8-12 weeks (average 9.5 weeks).Parents of 9 children were satisfied with surgical operation effect and deformity correction.The Constant-Murley scores ranged from preoperative average of (20.44 ± 2.79) points (16-24 points) to postoperative average of (35.56 ± 2.60) points(30-38 points) at the latest follow-up of patients,there was a statistically significant in score before and after treatment(t =0.20,P ＜0.05).Number 4 patient,one patient was found suffering from dorsal thumb numbness postoperatively after 3 days back stretching limitation.Considering the radial nerve stretching injury,treatment with neurotrophic drug for 3 months,symptoms disappeared.There was no infection,or osteomyelitis,no vascular damages.Epiphyseal plate injury or premature closure and affecting growth were not found in all of the patients at the latest follow-up examination.Conclusions Treatment with osteotomy and peter-williams intramedullary nail fixation on children with humerus deformity due to osteogenesis imperfecta is advantaged.It gets less damages,no intruding shoulder joint,less bleeding.The greatest degree of correction of the deformity can be achieved,and the shoulder joint function and the quality of life can be improved.

Objective To assess the value of cardiac magnetic resonance (CMR) imaging in left ventricular structure and function in patients with end stage renal disease (ESRD).Methods Twenty-five patients with ESRD and 10 healthy subjects underwent CMR.Left ventricular end diastolic volume(EDV),end-diastolic diameter(EDD),end-systolic volume(ESV),end-systolic diameter(ESD),stroke volume(SV),ejection fraction(EF),LVM and interventricular septum (IVS) thickness were measured and compared.The parameters from CMR and 2DTTE were compared.Results The EF in patients with ESRD was significantly lower than that in controls (P＜0.001),while ESV,ESD,IVS and LVM were respectively higher than these in controls (P＜0.05).There was no significant difference (P＞0.05) in ESV between CMR and 2DTTE,but EF of CMR was significantly higher than this of 2DTTE (P＜0.05).There was no significant difference (P =0.296) in left ventricular systolic functional category.Bland-Altman plots showed a good agreement between the two methods.Conclusion CMR is a helpful tool to assess left ventricular structure and function in patients with ESRD.

Objective To investigate the feasibility of chemical exchange saturation transfer (CEST) imaging in the measurement of myocardial creatine (Cr) metabolites in phantom model using 3.0 T MR. Methods Five phantoms were made according to the volume percentage of Cr ranging from 10 to 50 mmol/L with an interval of 10 mmol/L. 3.0 T MR examinations with base protocol sequence,sequence with and without ECG were performed. Signal to noise,CrEST effect and Z spectra were analyzed. Comparison of signal noise ratio (SNR) among the three methods was performed using an analysis of variance. Bivariate correlations were obtained through Pearson analysis. Results Phantom studies demonstrated that different concentrations of Cr exhibited significant CEST effect with the three sequences. The SNR obtained by sequences with and without ECG were both higher than that of base sequence (both P<0.05). Moreover,no significance of SNR was found between sequences with and without ECG (P>0.05). There were positive correlation of MTR between sequences with ECG,sequences without ECG and base protocol sequence (r2= 0.974 and 0.997, both P<0.05). Conclusion Compared with base protocol sequence, the optimized sequence with ECG can acquire higher SNR CrEST images,indicating that myocardial CrEST imaging could be performed in clinical practice.

Different endophytes isolated from the seeds of Sophora flavescens were tested for their ability to produce matrine production. Response surface methodology (RSM) was applied to optimize the medium components for the endophytic fungus. Results indicated that endophyte Aspergillus terreus had the ability to produce matrine. The single factor tests demonstrated that potato starch was the best carbon source and the combination of peptone and NH₄NO₃ was the optimal nitrogen source for A. terreus. The model of RSM predicted to gain the maximal matrine production at 20.67 µg/L, when the potato starch was 160.68 g/L, peptone was 24.96 g/L and NH₄NO₃ was 2.11 g/L. When cultured in the optimal medium, the matrine yield was an average of 20.63 ± 0.11 µg/L, which was consistent with the model prediction. This study offered an alternative source for the matrine production by endophytic fungus fermentation and may have far-reaching prospect and value.
Aspergillus* ; Carbon ; Endophytes ; Fermentation* ; Fungi* ; Nitrogen ; Peptones ; Solanum tuberosum ; Sophora* ; Starch