Transistor amplifier is the key and difficult points in the teaching of medical electronics,however,most of the teaching materials on this content is insufficient.Meanwhile,medical students have little knowledge of engineering,so it is difficult for them to grasp the related knowledge.We introduced ‘ superposition theorem’ into the relevant teaching.Teaching practice proved that this reform made it easier for medical students to have an in-depth understanding of the content and better teaching effect was achieved.

The similarity and difference between stationary and mobile electronic linear accelerators in intra-operative radiation therapy are introduced. The contents and methods of quality assurance for stationary and mobile electronic linear accelerators and the key points to deliver intra-operative radiation therapy are described.

Animals ; Beverages ; Macrophages ; drug effects ; metabolism ; Mice ; Mice, Inbred Strains ; Receptors, Complement 3b ; metabolism

Objective To investigate the characteristics of post-transplantation diabetes mellitus and analyze its risk factors. Methods Extensive survey was carried out to understand the characteristics of post-transplantation diabetes mellitus in patients who received kidney grafting from February 1984 to December 2006. Results Three hundred forty-four post-transplantatian diabetes mellitus patients from 1872 ones after kidney grafting were found from February 1984 to December 2006. The prevalence of new onset post-transplant diabetes mellitus and impaired fasting glucose in kidney allograft recipients were 18. 4% and 12. 7% respectively, being significantly higher than that in general population and other inpatients. The options of immunosuppressants were significantly associated with the prevalence of post-transplantation diabetes mellitus. By multivariate logistic regression analysis, the baseline characteristics of the post transplantation diabetes mellitus patients were significantly associated with increased age(OR: 1. 309, P = 0. 049), elevated level of the triglyceride (OR: 1. 311, P = 0. 005), treatment with taerolimus (FK506) (OR: 1. 522, P = 0. 008), and large dose of intravenous pulsed prednisolane(OR: 1. 239, P = 0. 011), as compared with patients without post-transplantation diabetes mellitus. Besides, the number of patients with at least one acute rejection episode was significantly greater in the post-transplantation diabetic patients. Mycophenolate mofetil (OR: 0. 716, P = 0. 028) and diltiazem (OR: 0. 737, P =0. 015) were associated with lower risk of post-transplantation diabetes mellitus. Conclusions High prevalence of abnormal glucose metabolism in renal allograft recipients during hospitalization was observed. Many risk factors contributed to the development of post transplantation diabetes mellitus.

A new urine analysis core module based on high performance 32-bit microprocessor and high precision color sensor was presented. A novel optical structure and a specific circuit were applied to improve measurement precision and temperature was used to compensate for results in this core module. The information of urine test peice, such as all original data and color RGB value, reflectivity, semi-quantitative level, etc. can be output. The results showed that the measuring precision was about 95% or above with ideal stability and reliability using this presented core module, which can be conveniently applied in various urine analyzers, and can greatly decrease the cost of urine analyzers in development and production.
Color ; Equipment Design ; Microcomputers ; Reproducibility of Results ; Temperature ; Urinalysis ; instrumentation ; methods

Objective To explore the effect of keratinocyte growth factor(KGF)on the lung tissue and expres-sion of transforming growth factor - β1(TGF - β1 )in newborn rats with hyperoxia. Methods The 108 newborn SD rats were randomly divided into air group,hyperoxia group and KGF intervention group,and each group had 36 rats. The rats in every group were randomly divided into the 3,7,14 days subgroups,and each group had 12 rats. The rats in the hy-peroxia group and KGF intervention group were continually exposed to more than 950 mL/ L of oxygen box until the end of the experiment. KGF intervention group simultaneously undertook oxygen inhalation,hypodermic injection of 1 mg/ d recombinant human KGF(rhKGF)on the back on the first 3 days and 0. 5 mg/ d 3 days later till the end of the experi-ment. Air group and hyperoxia group were offered equivalent 9 g/ L saline. The rats in the air group took air. The sub -groups of the 3,7 and 14 days were cut for lung tissue in the corresponding time,observing lung tissue by light micro-scope for pathological changes and TGF - β1 protein expressed in the lungs was determined by immunohistochemistry. Results Air group sprout pulmonary alveolus on the 7th day,and the alveolaration finished on the 14th day,while hy-peroxia group had alveolar growth retardation and pulmonary fibrosis,but pulmonary fibrosis was not obvious in KGF in-tervention group. There was a significant difference on 7th day and 14th day between hyperoxia group and air group in TGF - β1(9. 43 ± 0. 64 vs 8. 62 ± 0. 52,P ﹤ 0. 05;9. 97 ± 0. 49 vs 8. 66 ± 0. 48,P ﹤ 0. 01). There was no significant difference between KGF intervention group and air group in TGF - β1(8. 67 ± 0. 55 vs 8. 56 ± 0. 43,8. 77 ± 0. 52 vs 8. 62 ± 0. 52,8. 81 ± 0. 47 vs 8. 66 ± 0. 48,all P ﹥ 0. 05). There's a significant difference on 7th day and 14th day be-tween hyperoxia group and KGF intervention group in TGF - β1(all P ﹤ 0. 05). Conclusions KGF can inhibit the pro-tein expression of TGF - β1 ,and this may be one of the possible mechanism underlying the protective effect of KGF a-gainst lung injury.

OBJECTIVETo evaluate the effect of IL-1beta on the expression of CDX2 in human gastric epithelial cell line GES-1 and its role in the intestinal metaplasia.

METHODSGES-1 cells were treated with IL-1beta in different concentrations and the expressions of CDX2 mRNA and protein were detected by real-time PCR, immunocytochemistry and Western blot at different time points. GES-1 cells were then pre-treated with NF-KappaB pathway inhibitor PDTC, and the expression of CDX2 mRNA and protein induced by IL-1beta were detected. The cell ultra-structure of GES-1 cells was observed by electronic microscope after GES-1 being treated with IL-1beta for 25 days.

RESULTSLevels of CDX2 mRNA and protein were 0.0749 + or - 0.0021 and 0.56 + or - 0.04 in the cells treated with 1 microg/L IL-1beta(P<0.05). After pre-treatment with PDTC, levels of CDX2 mRNA and protein were 0.0006 + or - 0.0002 and 0.40 + or - 0.06(P<0.05). Some changes in the cell ultra-structure of GES-1 were found by electronic microscope when GES-1 was treated with IL-1beta for 25 days.

CONCLUSIONIL-1beta can stimulate CDX2 mRNA and protein expression in GES-1 cells through the NF-KappaB signal pathway, indicating that IL-1beta plays an important role in the intestinal metaplasia.

CDX2 Transcription Factor ; Cell Line ; Epithelium ; metabolism ; pathology ; Gastric Mucosa ; cytology ; metabolism ; pathology ; Homeodomain Proteins ; metabolism ; Humans ; Interleukin-1beta ; pharmacology ; Metaplasia ; RNA, Messenger ; genetics

Animals ; Female ; Genes, MHC Class I ; Genes, MHC Class II ; Lung ; immunology ; pathology ; Mice ; Mice, Inbred C57BL ; Ovalbumin ; immunology ; Polymerase Chain Reaction ; RNA, Messenger ; analysis

OBJECTIVETo detect the expression of stem cell transcription factor Oct-4 in squamous cell carcinoma (SCC) and seborrheic keratosis (SK) and its association with cancer stem cells.

METHODSImmunohistochemistry was used to detect Oct-4 expression in 35 SCC cases, 21 SK cases and 15 normal control skin tissues.

RESULTSOct-4 expression was negative in normal skin and showed a significant difference between SCC and SK tissues (P<0.05).

CONCLUSIONThe Oct-4-positive cells in SCC and SK are probably tumor stem cells. Oct-4 expression may provide an important evidence for isolation and identification of human SCC and SK stem cells.

Adult ; Aged ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Case-Control Studies ; Female ; Humans ; Keratosis, Seborrheic ; metabolism ; pathology ; Male ; Middle Aged ; Octamer Transcription Factor-3 ; metabolism ; Skin Neoplasms ; metabolism ; pathology ; Young Adult

Objective To investigate the diagnosis and differential diagnosis of dermatofibrosarcoma protuberans (DFSP). Methods Totally, 50 patients with DFSP visiting the Institute of Dermatology, Chinese Academy of Medical Sciences from 1998 to 2014 were enrolled. The clinical manifestations, histopathological and immunohistochemical features, treatment and prognosis of DFSP were retrospectively reviewed. Results The average age at onset of DFSP was (29.5 ± 15.9)years in the 50 patients, with a mean disease duration of 9.57 years. Skin lesions most frequently occurred on the trunk(n = 33, 66.0%), followed by the extremities, head and neck. DFSP was characterized by atrophic patches or plaques in 13 cases (26.0%), multiple nodules varying in size and arising on atrophic plaques or patches in 30 cases (60.0%), single or multiple nodules arising on normal skin in 7 cases (14.0%). Histologically, the tumor consisted of uniform infiltrative spindle cells arranged in a storiform or cartwheel pattern. In addition, the tumor cells expressed CD34 and vimentin. Twenty patients experienced recurrence at the primary site after resection of skin lesions with a recurrence rate of 43.5%. No distant metastasis or death occurred in these patients. Conclusions DFSP usually has various skin manifestations, is easily misdiagnosed, and can be confirmed based on histopathological and immunohistochemical findings. Local recurrence of DFSP is common, and may occur for many times after surgical excision, but lymphatic and distant metastases are rare.