[Promote the high-quality development of gastrointestinal surgery with technological concept innovation].

In the past 30 years, gastrointestinal surgery in China has made significant progress, which is reflected in the gradual standardization of clinical diagnosis and treatment, significant improvement in surgical quality, improvement in short-term and long-term postoperative outcomes, and continuous development of high-quality clinical research. At present, the spectrum of disease in gastrointestinal surgery has changed from traditional benign diseases to malignant diseases represented by gastric cancer and colorectal cancer, metabolic diseases represented by obesity and diabetes, and immune diseases represented by inflammatory bowel disease. It is necessary to carry out full-cycle management for patients. In the new era full of opportunities and challenges, surgeons must be driven by innovation in surgical technology, guided by high-quality clinical research and guaranteed by standardized diagnosis and treatment of diseases, to continue to promote the high-quality development of gastrointestinal surgery in China.

[Fortify clinical advantages and promote innovative development: comparison of the Chinese Colorectal Cancer Surgery Database with foreign databases].

With the continuous development of evidence-based medicine, increasing attention has been paid to the construction of a large medical database to ensure a source of high quality real-world data. The Chinese Medical Association Colorectal Surgery Group created the Chinese Colorectal Cancer Surgery Database (CCCD), whose objective is to promote the development of colorectal surgery and improve patient prognosis with evidence-based medicine theory. Compared to major databases around the world, CCCD contains more comprehensive information on colorectal cancer surgical cases, recording the main epidemiological characteristics and detailed surgical information, but perioperative treatment data still need to be strengthened. It is necessary to continuously expand the coverage, enrich perioperative data and strengthen data, quality control. In the future, CCCD is expected to play a role in promoting homogenization of medical services, promoting smooth and effective graded diagnosis and treatment, giving full role to the characteristics of each center to achieve integrated development, and connecting real-world data and artificial intelligence.

[Current application and prospect of accurate navigation technology in orthopaedic trauma].

In the past decades,a dramatic development of navigation technology in orthopaedic surgery has been witnessed. By assisting the localization of surgical region,verification of target bony structure,preoperative planning of fixation,intraoperative identification of planned entry point and direction of instruments or even automated insertion of implants,its ability and potential to reduce operation time,intraoperative radiation,surgical trauma,and improve accuracy has been proved. However,in contrast to the widespread use of navigation technology in arthroplasty,orthopaedic tumor,and spine surgery,its application in orthopaedic trauma is relatively less. In this manuscript,the main purpose is to introduce the technical principles of navigation devices,outline the current clinical application of navigation systems in orthopaedic trauma,analyze the current challenges confronting its further application in clinical practice and its prospect in the future.

[From mini gastric bypass to one anastomosis gastric bypass, 20 years of one anastomosis gastric bypass].

In 2001, Rutledge reported the first case of mini gastric bypass (MGB). Carbajo improved the technique of MGB and named it one anastomosis gastric bypass (OAGB). Over the past 20 years, a large number of clinical and basic studies on OAGB/MGB have been reported, and the answers to some key questions about OAGB/MGB have gradually become clear. From a technical point of view, MGB and OAGB can be regarded as two subvariants of one surgery. The advantages of OAGB/MGB include: (1) simplicity, safety and lower probability of internal hernia;(2) stable and durable weight reduction effect; (3) stable and durable remission rate of type 2 Diabetes. The disadvantages of OAGB/MGB include: (1) bile reflux; (2) higher risk of malnutrition. OAGB/MGB has achieved a good balance between effectiveness and safety, and has become the most noticed and fastest-growing bariatric and metabolic procedure in recent years. OAGB/MGB has been recommended as a standard bariatric and metabolic procedure by IFSO and ASMBS.

[Prognosis factors for non-reversal of defunctioning ileostomy in patients with radical resection of rectal cancer].

Objective: To examine the prognosis factors for non-reversal of defunctioning ileostomy in rectal cancer surgery. Methods: The data of 234 patients with rectal cancer undergoing radical resection and defunctioning ileostomy in the Department of General Surgery, Beijing Friendship Hospital, Capital Medical University from January 2013 to June 2020 was analyzed retrospectively. There were 166 males and 68 females, aging (M(IQR)) 62(12) years (range: 33 to 89 years). Telephone following-up was conducted intensively in July 2021 to investigate whether stoma was reversed, causes of reversal failure, and tumor recurrence or metastasis after surgery. The non-reversal stoma was defined as stoma not being reversed during the follow-up period (more than 12 months). The χ2 test or Fisher's exact test was used to conduct a univariate analysis of clinical data related to reversal failure, and the factors with P<0.05 were selected into Logistic regression for multivariate analysis. Results: A total of 165 patients received stoma reversal postoperatively with an interval time of (6.5±2.4) months (range: 0.9 to 17.8 months), but 69 patients failed to closure of stoma. Univariate analysis showed that age, concomitant diseases, surgical methods, preoperative hemoglobin, preoperative carcinoembryonic antigen, tumor maximum diameter, depth of invasion, lymph node metastasis, TNM stage, anastomotic-related complications, postoperative tumor local recurrence or distant metastasis were associated with non-reversal of diverting ileostomy in rectal cancer surgery (all P<0.05). Multivariate analysis showed that age (OR=2.270, 95%CI: 1.150 to 4.479, P=0.018), open surgery (OR=7.249, 95%CI: 1.977 to 26.587, P=0.003), preoperative hemoglobin<120 g/L (OR=3.092, 95%CI: 1.566 to 6.105, P<0.01), anastomotic-related complications (OR=4.375, 95%CI: 1.686 to 11.349, P=0.002), postoperative local recurrence or distant metastasis (OR=7.065, 95%CI: 2.591 to 19.264, P<0.01) were independent prognosis factors for reversal failure of defunctioning stoma in rectal cancer surgery. Conclusions: There is a high risk of reversal failure of defunctioning ileostomy among rectal cancer patients with age>65 years, open surgery, preoperative hemoglobin<120 g/L, anastomotic-related complications, postoperative local recurrence or distant metastasis. Colorectal surgeons should fully evaluate the outcome and risk of reversal failure before making a decision of diverting ileostomy. Reducing anastomotic complications is helpful to the successful return of preventive ileostomy.

[Short-term complications after transanal total mesorectal excision for mid-low rectal cancer].

Objective: To summarize short-term postoperative complications of transanal total mesorectal excision (taTME) in the treatment of middle-low rectal cancer. Methods: A descriptive case series of cases was constructed. Clinical data of consecutive 83 patients with mid-low rectal cancer who received taTME treatment from November 2016 to April 2021 at Department of General Surgery of Beijing Friendship Hospital, Capital Medical University were collected. Among 83 patients, 58 (69.9%) were males, with a mean age of (61.4±11.8) years; 42 (50.6%) were low rectal cancer, 41 (49.4%) were middle rectal cancer. Short-term postoperative complication was defined as complication occurring within 30 days after operation. The complication was graded according to the Clavien-Dindo classification. At the same time, the morbidity of short-term postoperative complication in the first 40 patients and that in the last 43 patients were compared to understand the differences before and after passing the taTME learning curve. Results: Two patients (2.5%) were converted to laparotomy ; 78 (94.0%) completed anastomosis.While 5 (6.0%) underwent permanent stoma. The total operation time of transabdominal+ transanal procedure was (246.9±85.0) minutes, and the median intraoperative blood loss was 100 (IQR: 100) ml. Seventy-five cases (75 /78, 96.2%) underwent defunctioning stoma, including 74 cases of diverting ileostomy, 1 case of diverting transverse colostomy and 3 cases without stoma. The morbidity of complication within 30 days after operation was 38.6% (32/83), and the morbidity of complication after discharge was 8.4% (7/83). Minor complications accounted for 31.3% (26/83) and major complications accounted for 7.2% (6/83). No patient died within 30 days after operation. The incidence of anastomotic leakage was 15.4% (12/78). Eight patients (9.6%) were hospitalized again due to complications after discharge. The median postoperative hospital stay was 7 (IQR: 3) days. All the patients with minor (I-II) complications received conservative treatment. One patient with grade C anastomotic leakage was transferred to intensive care unit and received a second operation due to sepsis and multiple organ dysfunction. Two patients with paralytic ileus (Clavien-Dindo IIIa) underwent endoscopic ileus catheter placement. There were 3 patients with Clavien-Dindo III or above respiratory complications, including 1 patient with pleural effusion and ultrasound-guided puncture, 2 patients with respiratory failure who were improved and discharged after anti-infection and symptomatic treatment. One patient underwent emergency ureteral stent implantation due to urinary infection (Clavien-Dindo IIIb). The morbidity of postoperative complication in the first 40 cases was 50.0% (20/40), and that in the latter 43 cases decreased significantly (27.9%, 12/43), whose difference was statistically significant (χ(2)=4.270, P=0.039). Conclusions: The procedure of taTME has an acceptable morbidity of short-term postoperative complication in the treatment of mid-low rectal cancer. The accumulation of surgical experience plays an important role in reducing the morbidity of postoperative complication.

Observation of perfect diamagnetism and interfacial effect on the electronic structures in infinite layer Nd0.8Sr0.2NiO2 superconductors.

Nickel-based complex oxides have served as a playground for decades in the quest for a copper-oxide analog of the high-temperature superconductivity. They may provide clues towards understanding the mechanism and an alternative route for high-temperature superconductors. The recent discovery of superconductivity in the infinite-layer nickelate thin films has fulfilled this pursuit. However, material synthesis remains challenging, direct demonstration of perfect diamagnetism is still missing, and understanding of the role of the interface and bulk to the superconducting properties is still lacking. Here, we show high-quality Nd0.8Sr0.2NiO2 thin films with different thicknesses and demonstrate the interface and strain effects on the electrical, magnetic and optical properties. Perfect diamagnetism is achieved, confirming the occurrence of superconductivity in the films. Unlike the thick films in which the normal-state Hall-coefficient changes signs as the temperature decreases, the Hall-coefficient of films thinner than 5.5 nm remains negative, suggesting a thickness-driven band structure modification. Moreover, X-ray absorption spectroscopy reveals the Ni-O hybridization nature in doped infinite-layer nickelates, and the hybridization is enhanced as the thickness decreases. Consistent with band structure calculations on the nickelate/SrTiO3 heterostructure, the interface and strain effect induce a dominating electron-like band in the ultrathin film, thus causing the sign-change of the Hall-coefficient.

[Problems exposed in retrospective study of postoperative complications of rectal cancer and causal analysis].

Rectal cancer is a great threat to the health of the Chinese people. With the continuous improvement of surgical treatment level, complication as an important indicator to measure the safety of surgery has received increasing attention from clinicians both at home and abroad. Although there are many studies on postoperative complications of rectal cancer, the morbidity of complication reported by related studies varies greatly. An important reason occurs in the limitations of retrospective research, such as incomplete medical records, unclear diagnostic criteria for some complications, incomplete follow-up records after discharge, and poor communication mechanisms among MDT members. Starting from a retrospective study on postoperative complications of rectal cancer and finding out the defects and problems in the registration of complications in each center, then clarifying the definition of various postoperative complications, so as to establish a sound and standardized registration system, and carry out prospective research, this path could be a reliable method to obtain relatively accurate postoperative complications of rectal cancer.

MIR-147B Regulated Proliferation and Apoptosis of Gastric Cancer Cells by Targeting CPEB2 Via the PTEN Pathway.

The present study has been performed to illustrate the role and mechanism of microRNA-147b (miR-147b) in the cellular viability and apoptosis of gastric cancer (GC) cells. The GC tissues of 50 patients with complete data and the adjacent tissues were selected from Shanxi Cancer Hospital, and 3 pairs of tissues were randomly selected for microarray detection of high-expressing microRNAs. The expressions of miR-147b were quantified in numerous GC cell lines, i.e., BGC-823, SGC-7901, AGS, MGC-803 and MKN-45, normal tissue cell lines and 50 pairs of gastric cancer tissues. Moreover, two cell lines of miR-147b high-expressing used PCR quantitative analysis were selected for transfection experiments. The differentially expressed miR-147b was screened from 3 pairs of samples by miRNA chip. The expression ofmiR-147b was found highly expressed in gastric cancer tissues of 50 pairs of gastric cancer and adjacent tissues. The miR-147b found in diverse range in each of GC cell line. Therefore, two cell lines, BGC-823 and MGC-803, with relatively high expression levels of miR-147b were selected for further analysis and research. Scratch analysis results showed that compared with miR-147b NC, the miR-147b inhibitor group inhibited GC cell growth and reduced cell migration. The early apoptosis of MGC-803, and BGC-823 cells was enhanced by miR-147b inhibitor. miR-147b inhibitor significantly repressed the proliferation of BGC-823 and MGC-803 cells. Our study showed that the high expression of miR-147b is positively correlated with the occurrence and development of gastric cancer.

[Looking forward to the future direction of colorectal surgery in the perspective of clinical research and data collection].

Colorectal surgery has been developed rapidly in China because of the advance of minimally invasive surgical techniques, perioperative comprehensive treatment strategies and clinical research in recent years. Comparing the current diagnosis and treatment of colorectal cancer between China and western industrialized countries, it can be found that the specialized construction and standardized diagnosis and treatment of colorectal surgery in western industrialized countries are very mature, and the multidisciplinary diagnosis and treatment model of colorectal cancer has been standardized. Although there is almost no difference between high-level colorectal cancer centers in the eastern coastal areas of China and western countries, due to the vast size and uneven regional development of China, standardized surgery and standardized treatment concepts of colorectal surgery still need to be popularized. Combined with the current diagnosis and treatment of colorectal cancer in China, more high-quality clinical research should be carried out to seek new development and breakthroughs in the field of colorectal surgery. Combined with the experience of international and domestic clinical research that has been participated in or carried out, the author believes that quality control of clinical research should be carried out from the following two points: 1. structured training and quality control of research; 2. establishment and management of databases. In a word, we should not only focus on colon surgery itself, but also complete the transformation to research-oriented doctors and research-oriented disciplines, cultivate the concept of data collection and clinical research, enhance the scientific awareness of clinical research, and integrate high-quality data collection and clinical research into daily clinical practice. Only in this way can we fundamentally improve the comprehensive strength of China's colorectal surgery, effectively carry out surgical-related clinical research based on the current situation colorectal diseases in China, and obtain high-level evidence-based medical evidence based on the research results of the population of patients in China, and form a guide for the diagnosis and treatment of colorectal surgery in China, which will also guide the clinical practice of patients with colorectal diseases in China. This will certainly be a new direction for the development of Chinese colorectal surgery.

[Research progress on early diagnosis and prevention of anastomotic leak after rectal cancer surgery].

Anastomotic leak is a common and serious complication after anterior rectal resection. Despite the continuous advancement of anastomotic instruments and surgical techniques, the incidence of anastomotic leak has not decreased significantly compared with the past. As more studies on the early diagnosis of anastomotic leak are published, postoperative risk factors of anastomotic leak, such as fever, time to first bowel movement, CT, C-reactive protein (CRP) and procalcitonin (PCT), matrix metalloproteinase-9, and other cytokines and biomarkers (IL-6, TNF-α, lactate, pH, urinary neopterin/creatinine ratio), provide a reference for surgeons to assess the risk and increase the possibility of early diagnosis of anastomotic leak. Nevertheless, preventing the occurrence of anastomotic leak is still the ultimate goal. For the prevention of anastomotic leak, intraoperative ICG fluorescence imaging technology provides a simple and safe objective method for surgeons to evaluate anastomotic perfusion. The diversion stoma may reduce the incidence of anastomotic leak. More and more evidence shows that drainage through the anal canal can reduce the incidence of anastomotic leak after rectal cancer, but whether different types of drainage catheters can clearly reduce the incidence of anastomotic leak still needs more evidence. In addition, there has not yet been a unified opinion on the retention time and location of the drainage catheter. At present, the research of anastomotic leak has not adopted a unified definition and the heterogeneity among related studies is still great. We still look forward to more high-quality multi-center large prospective and randomized controlled studies.

[Incidence and risk factors of anastomotic leak after transanal total mesorectal excision in China: a retrospective analysis based on national database].

Objective: Transanal total mesorectal excision (taTME) was a very hot topic in the first few years since its appearance, but now more introspections and controversies on this procedure have emerged. One of the reasons why the Norwegian Ministry of Health stopped taTME was the high incidence of postoperative anastomotic leak. In current study, the incidence and risk factors of anastomotic leak after taTME were analyzed based on the data registered in the Chinese taTME Registry Collaborative (CTRC). Methods: A case-control study was carried out. Between November 15, 2017 and December 31, 2020, clinical data of 1668 patients undergoing taTME procedure registered in the CTRC database from 43 domestic centers were collected retrospectively. After excluding 98 cases without anastomosis and 109 cases without complete postoperative complication data, 1461 patients were finally enrolled for analysis. There were 1036 males (70.9%) and 425 females (29.1%) with mean age of (58.2±15.6) years and mean body mass index of (23.6±3.8) kg/m(2). Anastomotic leak was diagnosed and classified according to the International Study Group of Rectal Cancer (ISREC) criteria. The risk factors associated with postoperative anastomotic leak cases were analyzed. The impact of the cumulative number of taTME surgeries in a single center on the incidence of anastomotic leak was evaluated. As for those centers with the number of taTME surgery ≥ 40 cases, incidence of anastomic leak between 20 cases of taTME surgery in the early and later phases was compared. Results: Of 1461 patients undergoing taTME, 103(7.0%) developed anastomotic leak, including 71 (68.9%) males and 32 (31.1%) females with mean age of (59.0±13.9) years and mean body mass index of (24.5±5.7) kg/m(2). The mean distance between anastomosis site and anal verge was (2.6±1.4) cm. Thirty-nine cases (37.9%) were classified as ISREC grade A, 30 cases (29.1%) as grade B and 34 cases (33.0%) as grade C. Anastomotic leak occurred in 89 cases (7.0%,89/1263) in the laparoscopic taTME group and 14 cases (7.1%, 14/198) in the pure taTME group. Multivariate analysis showed that hand-sewn anastomosis (P=0.004) and the absence of defunctioning stoma (P=0.013) were independently associated with anastomotic leak after taTME. In the 16 centers (37.2%) which performed ≥ 30 taTME surgeries with cumulative number of 1317 taTME surgeries, 86 cases developed anastomotic leak (6.5%, 86/1317). And in the 27 centers which performed less than 30 taTME surgeries with cumulative number of 144 taTME surgeries, 17 cases developed anastomotic leak (11.8%, 17/144). There was significant difference between two kinds of center (χ(2)=5.513, P=0.019). Thirteen centers performed ≥ 40 taTME surgeries. In the early phase (the first 20 cases in each center), 29 cases (11.2%, 29/260) developed anastomotic leak, and in the later phase, 12 cases (4.6%, 12/260) developed anastomotic leak. The difference between the early phase and the later phase was statistically significant (χ(2)=7.652, P=0.006). Conclusion: The incidence of anastomotic leak after taTME may be reduced by using stapler and defunctioning stoma, or by accumulating experience.

[Effect of subpressure on the bonding strength of resin to polycrystalline particulates modified zirconia ceramic].

Objective: To explore the effect of subpressure on the bonding strength of resin to polycrystalline particulates modified zirconia ceramic. Methods: One hundred and twenty pre-sintered zirconia discs were prepared and divided into the control group, the sandblasting group and the 30, 50, 70 s acid etching group (24 per group) by the random number table method. There was no additional treatment in the control group and sandblasting group before sinering. The 30, 50, and 70 s acid etching groups were immersed in HF for 30, 50, 70 s, respectively, and then they were placed into CaCl2 solution for 90 s and dipped in NaOH solution at 80 ℃ for 2 h. After sintering, the sandblasting group was subjected to sandblasting. The surface tomography and roughness were tested. According to whether subpressure was applied or not after the adhesives were applied, each group was randomly divided into two subgroups with a random number table: a subpressure subgroup and a normal pressure subgroup (12 per subgroup). Resin columns were bonded to these specimens. Shear bonding strength (SBS) test was conducted and the bonding interface, fracture surface and failure mode were analyzed. Results: The surface of control group was smooth, and its roughness was (0.24±0.11) µm. The rough surface was formed after sandblasting in the sandblasting group, and its roughness was (0.95±0.12) µm. The surface roughness of 30, 50, 70 s acid etching groups [(0.60±0.15), (1.04±0.11), (1.57±0.16) µm] increased as the HF immersion time prolonged, and the difference in surface roughness of zirconia specimens among each group was statistically significant (P<0.05). The SBS values between zirconia and resin of all the subpressure subgroups, namely: the control group, the sandblasting group, and the 30, 50, 70 s acid etching group [(13.56±1.19), (20.98±2.11), (17.37±2.44), (24.19±2.97), (21.36±2.16) MPa] were significantly stronger than those in the normal pressure subgroups, namely: the control group, sandblasting group, 30, 50, 70 s acid etching group [(10.74±0.93), (18.47±2.14), (14.81±1.54), (20.74±2.56), (17.75±2.54) MPa] (P<0.05). No obvious gaps and bubbles were observed in the bonding interfaces in subpressure subgroups. The proportion of mixed failure was significantly increased after applying subpressure (P<0.05). Conclusions: The subpressure can effectively enhance the bonding strength between the resin and polycrystalline particulates modified zirconia ceramic and improve the bonding effect.

[Analysis of the clinical confusion and controversy of esophagogastric junction tumor from basic anatomy].

There are still many controversies in the surgical treatment of esophagogastric junction tumors in terms of surgical approach, cleaning range, and resection scope. The reason is the confusion about the scope of the esophagogastric junction. The previous domestic and foreign anatomy descriptions of this part are not enough to solve the current problems. Based on a large number of basic anatomy and clinical operations, this article proposes that the esophagogastric junction may be wrapped by a complete and separate esophagogastric junction membrane with independent anatomy other than infracardiac bursa. The structure of the transitional tissue, mainly from the distribution of submucosal veins, explained the relationship and significance of tissue transitional changes and clinical operations, and made a reasonable analysis of the current controversy based on the anatomical characteristics, which is worthy of further investigation.

[The development process and new requirements of structured training on transanal total mesorectal resection].

Due to the technical difficulty and long learning curve, the benefits of Transanal total mesorectal excision may be obscured by surgical complications that arise from rapid, large-scale development, therefore the surgeons need to receive sufficient training before performing this surgery. At present, a mature structured training system has been formed, but the development of structured training has not met the needs of existing surgical development. In order to standardize the development of transanal total mesorectal excision, the European Society of Colorectal Diseases and 14 international surgical societies recently launched the "International Expert Consensus Guidelines for the Indication, Implementation and Quality Evaluation of Transanal Total Mesorectum Resection". The consensus involves the requirements for trainees, the content and process of training, as well as the evaluation and registration of training results. Training in cadaver is the core of structured training. Beginners should receive repeated training and conduct the surgery under the guidance of instructors.

[Interpretation of international expert consensus guidance on indications, implementation and quality measures for transanal total mesorectal excision].

In recent years, transanal total mesorectal excision (taTME) has been a hot spot in the field of colorectal surgery. Compared with the traditional laparoscopic technique, taTME has potential advantages in the treatment of rectal diseases. However, the procedural safety and effectiveness of taTME need further verification. In order to ensure the safe and standardized implementation of this procedure, the European Society of Coloproctology, together with 14 international academic organizations related to colorectal surgery and minimally invasive surgery, has developed the international expert consensus guidance on indications, implementation and quality measures for taTME. This paper introduces the background of the international consensus guidance, and interprets its core contents, including the surgical indications (complex pelvic conditions, malignant and benign rectal diseases), surgical quality and outcome evaluation, structured training, and expert center. It is expected to provide reference and guidance for Chinese colorectal surgery colleagues performing taTME.

Ferromagnetic frustration in ternary nitride ZnFe3N.

As a new antiperovskite nitride, ZnFe3N was synthesized and characterized by almost completely substituting iron atoms at corner positions of γ'-Fe4N. The magnetic interactions of the system with the space group Pm3[combining macron]m are fully investigated. The critical behavior was investigated based on the measured magnetic data around the ferromagnetic phase transition temperature. In this work, the values of critical exponents (ß, γ and δ) were obtained systematically using the Kouvel-Fisher method in the critical region. The Widom scaling law (δ = 1 + γß-1) and the scaling equation (m = f±(h)) were used to reveal the reliability of these values. The values of the critical exponents (ß = 0.325, γ = 1.228, and δ = 4.778) are different from those predicted by the three-dimensional (3D) Heisenberg model and mean-field model, and are very close to those of the 3D-Ising model. Combined with ESR analysis, the spin clusters induced by changes in chemical bonds are considered to be the cause for the existence of an anisotropic short-range ordered state in this ferromagnetic system.

[Medical imaging clinical appropriateness:rational examination according to evidence-based medical imaging].

The rational clinical examination is important. The authors raised the concept of "medical imaging clinical appropriateness (MICA) " to meet the medical need in clinic (for diagnosis or assessment of a kind of disease or syndrome), which means radiologists and clinicians work together to carefully evaluate the necessity and rationality of an examination according to evidence of evidence-based medicine, expertise, experience, and patient's willing.The necessity is prerequisite, the rationality is the core, the evaluation of evidence is the basis, the application of evidence-based medicine is the important method. This work will provide us a series of criteria in the format of guidelines, providing evidence of rational examination for clinicians. Based on hard working and cooperation between radiologists and clinicians, we will establish the system of MICA in China, standardizing medical process, promoting rationalization, optimizing medical resources allocation and usage.

Cavity ring-down spectroscopy based on a comb-locked optical parametric oscillator source.

Spectroscopy of molecules in the mid-infrared (MIR) region has important applications in various fields, such as astronomical observation, environmental detection, and fundamental physics. However, compared to that in the near-infrared, precision spectroscopy in the MIR is often limited by the light source and has not shown full potential in sensitivity. Here we report a cavity ring-down spectroscopy system using a tunable narrow-linewidth optical parametric oscillator, which fulfills the requirement of high sensitivity and high precision in the MIR region. The Lamb-dip spectrum of the N2O molecule at 2.7 µm was measured as a demonstration of spectroscopy in the MIR with kilohertz accuracy.