There is no corresponding product standard and industry standard for the search and development of magnetocardiograph at home and abroad. In this paper, based on the working principle and clinical application function of magnetocardiograph, and on the basis of relevant regulations and normative documents of medical device registration, some thoughts and concerns about the technical review of this kind of product are put forward.
Industry ; trends ; Magnetocardiography ; standards

Percutaneous renal puncture device has very important clinical value. Qualified percutaneous renal puncture device is one of the important ways to evaluate its safety and efficacy, and it is also an important prerequisite for the device to be marketed in China. When manufactuers test the product, the selection of representative products is suggested from the aspects of performance parameter, structure, material and production process.
China ; Humans ; Kidney ; Nephrostomy, Percutaneous ; instrumentation ; Punctures

ObjectiveTo investigate the etiology and management of male urethral stricture at 8 medical centers in China during the period from 2004 to 2009 years,and to investigate whether there were any changes in etiology and management of urethral stricture with time change.MethodsThe database on 3455 male patients with urethral stricture who underwent treatment at 8 medical centers in China between January 2004 and December 2009 were prospectively collected.The databases were analyzed for possible cause of stricture and treatment techniques for urethral stricture,and for the changes in etiology and management with time change.ResultsThere were 3455 operations for urethral stricture during the study period.The main causes of urethral strictures were traumas in 1833 patients (53.05％),among which pelvic fractures were in 1327 (38.41％) and perineal trauma in 506 (14.65％).The second cause was iatrogenic causes in 1181 patients (34.18％ ),among which transurethral operations or examinations were in 602 (17.42％),hypospadias surgery in 291 (8.42％) and urethral catheterization in 164 (4.75％ ).Less common causes were urethritis in 201 patients (5.82％),lichen sclerosus in 149 (4.31％),undefined in 91 (2.63％).The treatments of urethral strictures were endourological surgery including internal urethrotomy and dilation and open urethroplasty including end-to-end urethroplasty and the substitude urethroplasty etc.The ratios of using various techniques in total number of patients were obviously different by time.The most application technique for treatment of urethral stricture was endourological surgery ( 709 ) during 2004 -2006 and occupied 52.67％ in total number of patients.It was gradually decreased during 2007 -2009 (726) and only occupied 34.42％ (P ＜0.01 ).Open urethroplasty gradually increased during 2007 -2009 ( 1243,58.94％ ) compared with the first three years (563,41.83％ ) (P ＜ 0.01 ). Conclusions During the recent years there was an increase in the incidence of urethral stricture being trauma and iatrogenic causes.The main treatments of urethral strictures were endourological surgery and open urethroplasty.Endourological surgery was significantly decreased in total number of patients,while open urethroplasty were significantly increased during the late three years.

Objective:To explore the feasibility and conditions of in vitro and in vivo imaging of triple-negative breast cancer using visible light emitted quantum dots(QDs) as the carrier to target epidermal growth factor receptor (EGFR). Methods:The water-soluble QDs reacted with Cetuximab to synthesize the probe QD-Cetuximab. The morphology, particle size, stability and luminescence properties of the probe were examined. Human breast cancer cells MDA-MB-468 (EGFR+ ) and MDA-MB-453 (EGFR-) were cultured. Cytotoxicity assays, in vitro imaging and fluorescence intensity quantification were performed after cells incubation with QD-Cetuximab and QDs. Eight MDA-MB-468 tumor-bearing mice models were constructed, 100 μl QD-Cetuximab and QDs were injected through the tail vein. In vivo imaging and probe distribution were obtained at different time points. Independent-sample t test was used to analyze the data. Results:QD-Cetuximab had a particle size of (40.34±2.44) nm detected by transmission electron microscope (TEM), a hydrated particle size of (57.85±4.69) nm detected by dynamic light scattering (DLS), and a stable structure. When the concentration of QD-Cetuximab was ≤50 nmol/L, the relative survival rate of cells was more than 90%, and when the concentration exceeded 100 nmol/L, the relative survival rate of cells was reduced to (72.52±4.91)% ( P<0.05). The red fluorescence of MDA-MB-468 incubated with QD-Cetuximab was stronger than that of MDA-MB-468 incubated with QDs and MDA-MB-453 incubated with QD-Cetuximab or QDs. The confocal fluorescent intensity quantitative determination showed that the ratio of QD-Cetuximab group/QDs group was 5.1 (863.36/169.97). Flow cytometry showed that the uptake of QD-Cetuximab and QDs by MDA-MB-468 increased with incremental incubating concentration, and the former was more significantly( t values: 12.25-38.11, all P<0.05). When the incubating concentration was 25, 50, 100, and 200 nmol/L, the quantitative average fluorescent intensity ratio of QD-Cetuximab group/QDs group was 5.4, 6.9, 7.4 and 6.2, respectively. The QD-Cetuximab and QDs probes mainly accumulated in the liver in vivo. The fluorescence emitted by tumor was not obvious under the high fluorescence of liver as a background. However, the fluorescence was visible in the isolated tumor tissue, and the quantitative fluorescence intensity of experimental group and control group were (2.46±0.60)×10 4 and (1.29±0.05)×10 4, respectively ( t=3.392, P=0.015). Conclusions:Cetuximab can increase the targeting ability of QDs and promote cell uptake. Although the isolated tumor imaging results are acceptable, further modification of QDs should be considered to reduce the liver uptake and improving in vivo fluorescence imaging efficiency.

ObjectiveTo investigate the mechanism of Yiqi Huoxue Tongluo prescription （YHTP） in the treatment of diabetic neuropathic pain （DNP）. MethodNinety SPF-grade SD male rats were randomized into blank， model， low- （2.25 g·kg^-1）， medium- （4.5 g·kg^-1）， and high-dose （9 g·kg^-1） YHTP， and mecobalamin （0.175 mg·kg^-1） groups. Except those in the blank group， the rats in the remaining 5 groups were fed with a high-fat and high-glucose diet and subjected to intraperitoneal injection of low-dose （35 mg·kg^-1） streptozotocin （STZ） to establish the model of DNP. The sciatic nerve conduction velocity in DNP rats was measured by the neurophysiological method， and the levels of interleukin-6 （IL-6）， IL-1β， and tumor necrosis factor-α （TNF-α） were measured by enzyme-linked immunosorbent assay （ELISA）. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was employed to measure the mRNA levels of glial fibrillary acidic protein （GFAP） and extracellular signal-regulated kinase （ERK） in the spinal cord. Western blot was employed to measure the protein levels of GFAP and phosphorylated ERK （p-ERK）， and immunofluorescence staining to measure the fluorescence intensity of GFAP and p-ERK in the spinal cord. In the cell experiments， 100 mmol·L^-1 high glucose was used to induce the activation of astrocytes （CTX-TNA2） for the modeling of nerve cell injury. The cells were randomized into the normal， model， drug-containing serum （10% YQHT）， inhibitor ［10 mol·L^-1 corynoxeine （COR）］， drug-containing serum + inhibitor （10% YHTP + 10 mol·L^-1 COR） groups. The levels of pro-inflammatory factors （TNF-α and IL-1β） and the anti-inflammatory factor IL-10 in CTX-TNA2 cells were determined by ELISA， and the protein levels of GFAP and p-ERK in CTX-TNA2 cells by Western blot. ResultThe animal experiments showed that compared with the blank group， the model group presented reduced mechanical withdrawal threshold （MWT）， thermal work limit （TWL）， and nerve conduction velocity， elevated levels of fasting blood glucose， IL-1β， TNF-α， and IL-6， and up-regulated protein levels of GFAP and p-ERK， and mRNA levels of ERK1， ERK2， GFAP （P<0.01）. Compared with model group， YHTP increased the MWT， TWL， and sciatic nerve conduction velocity （P<0.01）， lowered the levels of IL-1β， TNF-α， and IL-6 （P<0.01）， and down-regulated the protein levels of GFAP and p-ERK， and mRNA levels of ERK1， ERK2， GFAP in the spinal cord （P<0.05， P<0.01）. The cell experiments showed that compared with the blank group， the model group had decreased survival rate， elevated levels of pro-inflammatory factors， and up-regulated protein levels of ERK and GFAP （P<0.01）. Compared with the model group， the YHTP-containing serum lowered the levels of IL-1β and TNF-α （P<0.05， P<0.01）， elevated the level of IL-10 （P<0.01）， and down-regulated the protein levels of ERK and GFAP （P<0.01）. ConclusionYHTP may inhibit the activation of astrocytes by inhibiting the ERK signaling pathway to reduce inflammation and thus relieve DNP.