Based on quantum mechanics, rotational spectroscopy is a branch of fundamental science to study the rotational spectra of molecules, free radicals and ions, and has great applications on radio astronomy and many analytical fields such as atmospheric remote sensing. In this paper we reviewed the basic theory of rotational spectroscopy, two different types of Fourier transform microwave spectrometers, some typical spectroscopic analysis, and future prospect of the microwave spectroscopic techniques as well.

OBJECTIVE To investigate the clinical pathological characteristics of differentiated thyroid carcinoma (DTC) in children and adolescents. METHODS The clinical data of 30 children and adolescents with DTC were retrospectively reviewed. Meanwhile the clinical pathological characteristics of DTC were analyzed according to patients' age and gender. RESULTS Papillary thyroid carcinoma (PTC) was found in 27 cases and follicular thyroid carcinoma (FTC) in 3 cases. The average diameter of tumors was (2.56±1.1) cm. In the group of children, the incidence of lymph node metastasis was 92.3% (12/13), pulmonary metastasis was 46.2% (6/13), and those in the group of adolescents was 88.2% (15/17) and 35.3% (6/17) respectively. Children group tended to present with more vascular invasion, thyroid capsule invasion, and invasion out of thyroid, and a higher rate of cervical lymph node metastasis (P=0.025, 0.007, 0.025, 0.033). CONCLUSION Thyroid carcinoma in childhood and adolescent has a stronger invasive feature. It is easy to local invasion, lymph node and distance metastasis.

Objective To evaluate the morbidity trend of prostate cancer since the clinical usage of PSA was introduced in Beijing Hospital.Methods Retrospectively we analyzed prostate cancer cases diagnosed in Beijing Hospital from 1995 to 2008.The incidence, age, PSA and clinical stage at diagnosis were taken into account.Results Four hundred and thirty-two cases were enrolled into the study.Who were aged 40 - 90 years old, mean age 72.0 ± 7.8 years.The most frequent age at diagnosis was 70 to 79 years.The incidence increased annually with the most significant increase taking place in 2007 and 2008.Compared with the period 1995 to 1999, the localized prostate cancer rate between 2004 and 2008 increased from 23.9% to 36.3%; the metastatic prostate cancer rate decreased from 49.3% to 32.1%; the rate of patients with PSA 4 - 10 ng,/ml increased from 12.7% to 29.2%; the rate of PSA ＞ 100 ng/ml decreased from 22.5% to 13.2%.Conclusions The incidence and early detection rate of prostate cancer in Beijing Hospital increased from 1995 to 2008.The age at diagnosis had not significantly changed.However, the early detection rate should be improved.

To analyze respectively a case,presented with recurrent petechial and epistaxis after a 2 years history of diabetes mellitus (DM),who was hospitalized in Beijing Children's Hospital Affiliated to Capital Medical University.The clinical manifestation,examination,diagnosis and treatment were recorded.The patient was diagnosed with immune thrombocytopenia (ITP) and DM at the first admission.The initial therapy with gamma globulin didn't show ideal effect.The pediatric specialists from the department of ENT,Hematology/Oncology,Endocrinology,Pharmacy and Immunodeficiency Clinic were invited to discuss the case.The final diagnosis of autoimmune polyglandular syndrome (APS) was made and supplementary steroid treatment was started.But the response of the steroid therapy was poor.Once again with the multidisciplinary consultation,the patient received several schemes of Rituximab under the informed consent.This treatment reached a stable condition for almost 7 years.APS should be considered when DM patient showed the manifestation of other immune organ damages.Rituximab immunosuppressive therapy should be tried when the response to first-line treatment was poor.

Objective To explore the short-term efficacy in children with head and neck rhabdomyosarcoma (HN-RMS) treated by multidisciplinary therapy,and to analyze the prognostic factors,so as to guide the diagnosis and treatment.Methods Patients with HN-RMS admitted at Hematology Oncology Center of Beijing Children's Hospital (BCH),Capital Medical University between December 2012 and May 2017,were included in this case-observation study.The clinical characteristics were analyzed and the treatment effect and prognostic factors were summarized.Results A total of 48 cases were collected,including 36 boys and 12 girls,with a median age of 4.6 years.Primarysite parameningeal RMS(PM-RMS) (34 cases,70.8％),orbital (2 cases,4.2％) and non-orbital,non-parameningeal region(12 cases,25.0％) were found.Twenty cases belonged to alveolar type(41.7％),and 28 cases were of embryonaltype(58.3％).The diameter of the tumor was ＞5 cm(n =25,52.1％),and ≤5 cm(n =23,47.9％).IRS staging:there were 29 cases(60.4％) of stage Ⅱ-Ⅲ,19 cases (39.6％) of stage Ⅳ;29 cases (60.4％) of low-medium risk,and 19 cases (39.6％) of high risk.Twenty-three patients (47.9％) received surgery,and 25 cases (52.1％) received biopsy only.All patients (48 cases) received systemic chemotherapy.Twenty patients (41.6％) received external radiation,15 cases (31.3％) received 125I particle implantation,6 cases (12.5％) received proton therapy,but 3 cases (6.2％)did not receive radiation.The follow-up time lasted 13-57 months[(24.1 ± 12.3) months].The 2-year overall survival(OS) rate was (66.4 ± 7.2)％,and 2-year event free survival (EFS) rate was (59.9 ± 7.5) ％.Patients with tumor diameter ≤ 5 cm had higher OS and EFS than patients with tumor diameter ＞5 cm [2-year OS (87.4±6.8)％ vs.(42.9 ±6.8)％,2-year EFS (78.8 ±8.6％) vs.(38.5 ±10.8)％],and the differences were statistically significant (all P =0.006).Patients with orbital and non-orbital,non-parameningeal RMS had higher OS and EFS than PM-RMS [2-year OS 100％ vs.(87.5％ ± 11.7) ％ vs.(57.0 ± 8.8) ％;2-year EFS 100％ vs.(88.9 ± 10.5)％ vs.(51.1 ± 8.9)％],and the differences were statistically significant (P =0.008,P =0.030).Patients who received surgery had higher OS and EFS than those who did not received surgery [2-year OS (80.7±8.8)％ vs.(53.3 ± 10.4)％;2-year EFS (71.1 ±10.1)％ vs.(49.5±10.4)％],and the differences were statistically significant (P =0.008,P =0.026).COX regression analysis showed tumor diameter ＞ 5 cm was an adverse prognostic factor (OR =4.124,95％ CI:1.213-14.025,P =0.023).Conclusions PM-RMS accounted for a high proportion in RMS patients.The primary site and the size of the tumor are the main prognostic factors.Intensive therapy is expected to improve the prognosis of HN-RMS with meningeal invasion.

Ventilator is an indispensable emergency medical equipment in hospitals. The global outbreak of the coronavirus disease 2019 (COVID-19) has highlighted the importance of the ventilator, which has attracted the attention and research on ventilators of all countries in the world. This article reviews the development history of the ventilator, briefly introduces the main air circuit structure and working principle of the ventilator, and then deeply analyzes the key technologies of this device. In addition, it compares some major brands of ventilators from several aspects in the market. Finally, the development trend and perspective of ventilators are presented.
COVID-19 ; Equipment Design ; Home Care Services ; Humans ; Respiration, Artificial ; SARS-CoV-2 ; Ventilators, Mechanical

Objective:To determine the characteristics of cervical neuroblastoma and the effect of resection extent on survival and outcomes.Methods:We performed a retrospective review of 32 children with cervical neuroblastoma treated at Beijing Children′s Hospital between April 2013 and August 2020. Data were collected from the medical record. The individualized therapy was designed based on staging and risk group. Based on the extent of resection, patients were divided into incomplete and complete resection groups. Event free and overall survival rates were compared between two groups using the Kaplan-Meier method.Results:The ages of patients ranged from 1 month to 81 months, with a median age of 11 months, including 7 males and 15 females. Twenty-nine patients (90.6%) presented with cervical painless mass. The average diameter of the primary tumors was (5.12±1.43) cm. Tumors were located in the parapharyngeal space in 25 cases (78.1%) and in the root of the neck in 7 cases (21.9%). None had MYCN amplification. According to International Neuroblastoma Staging System (INSS), 15 patients (46.9%) were identified as stage 1, 11 patients (34.3%) as stage 2B, 3 patients (9.4%) as stage 3 and 3 patients (9.4%) as stage 4. There were 12 patients (37.5%) at low risk, 17 patients (53.1%) at intermediate risk and 3 patients at high risk according to Children′s Oncology Group (COG) risk classification system. All patients underwent tumor resection. Postoperatively Horner′s syndrome occurred in 13 patients (40.6%), pneumonia in 9 patients (28.1%), pharyngeal dysfunction in 8 patients (25.0%) and transient hoarseness in 4 patients (12.5%). At a median follow-up of 36.5 months, the overall survival rate was 96.4%, with no significant difference between incomplete and complete resection groups (100.0% vs. 96.3%, χ 2=0.19, P=0.667); the event free survival rate was 78.1%, with a significant difference between the two groups (40.0% vs. 85.2%, χ2=6.71, P=0.010). Conclusions:Primary cervical neuroblastoma has a young onset age, mostly in low and medium risk groups, and represents favorable lesions with good outcomes after multidisciplinary therapy. Less aggressive surgery with preservation of important structures is recommended. Complete resection should not be attempted if it would compromise vital structures.

Objective:To evaluate the efficacy and influencing factors of surgery combined with neoadjuvant chemoradiotherapy in the treatment of children with non-orbital head and neck rhabdomyosarcoma (HNRMS).Methods:Information from 45 children diagnosed as non-orbital HNRMS and subjected to surgery combined with neoadjuvant chemoradiotherapy in Beijing Children′s Hospital affiliated to Capital Medical University from August 2017 to July 2021 was analyzed. The patients included 25 males and 20 females, aged from 1 to 17 years old. The primary tumor site, pathological subtype, clinical stage, risk group, therapeutic regimen, resection range and outcome of all cases were also collected. The survival curves were made using the Kaplan-Meier method and the potential prognostic factors were investigated by Cox regression analysis.Results:Fifteen (33.3%) of 45 children achieved negative surgical margin under complete tumor resection. The postoperative pathological results showed that there were 20 cases of embryonic subtype, 19 cases of alveolar subtype and 6 cases of spindle sclerosis subtype. The postoperative follow-up time ranged from 4 to 71 months, with a median of 26 months. During the follow-up period, 13 children died, among whom brain metastasis was the most common cause of death, accounting for 7/13. The 3-year overall survival rate was 67.6%. Multivariate analysis showed that non-embryonic subtype ( HR=6.26, 95% CI: 1.52-25.87, P=0.011) and failure to reach R0 resection ( HR=9.37, 95% CI: 1.18-74.34, P=0.034) were independent risk factors affecting overall survival rate. Conclusion:Surgery combined with neoadjuvant chemoradiotherapy can offer a good efficacy for children with non-orbital HNRMS. Non-embryonic subtype and resection without negative operative microscopic margins are independent risk factors for poor prognosis, and brain metastasis is the main cause of death in these children.

Objective:To analyze the clinical characteristics and prognosis of infants with rhabdomyosarcoma (RMS), thus enhancing the understanding of this disease.Methods:Clinical data of all RMS patients younger than 12 months treated in the Hematology Oncology Center, Beijing Children′s Hospital, Capital Medical University from May 2006 to June 2019 were retrospectively analyzed, including the age, gender, histological type, tumor primary site, tumor size, and the prognosis.Patients were followed up until December 31, 2019.The 3-year event free survival (EFS) rate of children was performed by plotting the Kaplan-Meier survival curves.Results:A total of 15 RMS children younger than 12 months were enrolled, accounting for 4.9% of all RMS cases in the same period, including 6 males and 9 females.The median age at diagnosis was 7.0 months (3.0-11.5 months). Classified by the primary site, 40.0% (6 cases) located in the head and neck, followed by 26.7% (4 cases) located in the limbs, 26.7% (4 cases) located in other parts, and 6.7% (1 case) located in the urogenital system.Embryonal RMS, alveolar RMS and spindle cell RMS accounted for 46.6% (7 cases), 26.7% (4 cases), and 26.7% (4 cases), respectively.Ten cases (66.7%) were stage Intergroup Rhabdomyosarcoma Study (IRS)-Ⅲ and 1 case (6.7%) was in stage Ⅳ.There were 10 cases (66.6%) in the middle-risk group, 4 cases (26.7%) in the low-risk group, and 1 case (6.7%) in the high-risk group.Two cases had a larger than 5 cm primary tumor; lymph node involvement was confirmed in 3 cases, and pulmonary metastasis occurred in 1 case at the time of diagnosis.All children were treated with chemotherapy, and 13 cases received postoperative chemotherapy and 1 case received preoperative chemotherapy.One case were not operated.Only 3 children underwent radiotherapy, including 1 case underwent particle implantation and 2 cases received external radiotherapy.Among the 15 children with RMS, 5 cases had relapse and disease progression with the 3-year EFS rate of (59.1±14.5)%, and 2 died with the 3-year overall survival rate of (80.8±12.6)%.Conclusions:The median age of diagnosis of RMS in single-center infants is 7 months.Head and neck are the most common primary sites of RMS.Nearly 50% of the children have the primary site of RMS with poor prognosis.More than a quarter of the pathological subtypes are the spindle cell type.Local treatment significantly influences the local progression or recurrence of RMS.

Oxygen therapy is an effective clinical method for the treatment of respiratory disorders, oxygen concentrator as a necessary medical auxiliary equipment in hospitals, its research and development has been a hot spot. The study reviewed the development history of the ventilator, introduced the two preparation technique of the oxygen generator pressure swing absorption (PSA) and vacuum pressure swing adsorption (VPSA), and analyzed the core technology development of the oxygen generator. In addition, the study compared some major brands of oxygen concentrators on the market and prospected the development trend of oxygen concentrators.
Oxygen ; Oxygen Inhalation Therapy ; Hospitals ; Ventilators, Mechanical ; Equipment Design