PVC resin is widely used in medical and other industrial fields because of its good chemical corrosion resistance, wear resistance, low cost and simple production. In this study, the related research progress in the influence of resin polymerization degree, processing technology and processing aids on the mechanical properties of PVC was reviewed, and the influence rules of processing aids on the properties of PVC was analyzed. Relevant research results show that the increase of the resin polymerization degree can increase the strength of PVC, but at the same time reduce the toughness. The use of compression molding process is beneficial to improve the strength and modulus of PVC. The use of injection molding process is beneficial to improve the plasticity and toughness of the PVC. Properly increasing the processing temperature and the blending time can improve the toughness of PVC. Adding heat stabilizers can improve the plasticity, toughness and strength of PVC. Adding plasticizers can improve the strength and toughness of PVC. Adding modifiers can improve the strength and toughness of PVC.

OBJECTIVE: To explore the genetic etiology of recurrent hydatidiform mole (RHM) and provide accurate guidance for reproduction. METHODS: Peripheral venous blood samples of the probands with RHM and members from 5 unrelated pedigrees were collected. Genomic DNA was extracted by using routine method, and whole exome sequencing was carried out to detect variants of RHM-associated genes including NLRP7 and KHDC3L. Sanger sequencing and real-time quantitative PCR (RT-qPCR) were used to validate the candidate variants and delineate their parental origin. RESULTS: Homozygous or compound heterozygous variants of the NLRP7 gene were identified in four patients from three pedigrees, which included a homozygous deletion of exon 1 to 4 of NLRP7 in patient P1 and her elder sister, compound heterozygous variants of NLRP7 c.939delG (p.Q314Sfs*6) pat and c.1533delG (p.N512Tfs*4) mat in patient P2, and compound heterozygous variants of NLRP7 c.2389_2390delTC (p.A798Qfs*6) pat and c.2165A>G (p.D722G) mat in patient P4. All variants were interpreted as pathogenic or likely pathogenic according to the American College of Medical and Genomics (ACMG) guidelines. Among these, NLRP7 exons 1 to 4 deletion, c.939delG (p.Q314Sfs*6), c.1533delG (p.N512Tfs*4) and c.2389_2390delTC (p.A798Qfs*6) were unreported previously. CONCLUSION Variants of the NLRP7 gene probably underlay autosomal recessive RHM in the three pedigrees, and definitive molecular diagnosis is beneficial for accurate genetic counseling. Above finding has also enriched the spectrum of the NLRP7 variants underlying RHM.
Adaptor Proteins, Signal Transducing/genetics* ; Aged ; China ; Female ; Homozygote ; Humans ; Hydatidiform Mole/pathology* ; Mutation ; Pedigree ; Pregnancy ; Sequence Deletion

Objective:To compare the application and results in repairing wounds on shank and medial malleolus by perforator pedicled middle and lower third of posterior tibial flap, saphenous neurovascular flap and posterior tibial artery perforator plus saphenous neurovascular (double blood supply) flap.Methods:Clinical data of 60 patients with wounds on shank and medial malleolus and treated between August, 2015 and December, 2018 were analyzed. Among the patients, 25 were treated with perforator pedicled middle and lower third of posterior tibial flaps, 15 with saphenous neurovascular flaps, and 20 with double blood supply flaps. The data of surgery, survival of the flaps, texture and swelling of the flaps, patient satisfaction and scores set by American Orthopaedic Foot and Ankle Society(AOFAS) were collected. Statistic analysis was carried out to compare observations among the 3 groups.Results:Postoperative followed-up was 6 to 24(average 13.4) months. One flap suffered insufficient blood supply in the group of perforator pedicled middle and lower third of posterior tibial flaps, 2 flaps suffersd necrosis and skin graft was carried out in reverse saphenous nerve neurocutaneous flaps group. In double blood supply flaps group, 2 flaps appeared purple after surgery, and improved after removing the pedicle sutuer, and flaps became swelling and received secondary repair. All AOFAS scores (93.8, 93.3 and 92.8, respectively) and patient satisfaction were high in all 3 groups.Conclusion:All 3 types of flap are able to be used in repairing the soft tissue defect on shank and medial malleolus. The inclusive of saphenous nerve should be determined in intraoperation according to the presence and size of the perforator. If artery perforation is reliable, the use of posterior tibial artery perforator flap in wound repairing will deliver satisfactory outcomes in terms of blood supply and appearance of the flap. For the wider area of wound, a flap with double blood supply is preferred.

Hantavirus disease is a globally distributed, natural foci-related infectious disease caused by hantavirus, that maintaining persistent infections in their rodent hosts without apparent disease symptoms but seriously affecting the health safety of human beings. Development of the disease depends on the interaction between virus, rodent host and the individual person. Factors as significant geographical and seasonal variations, certain periodicity and contingency can all be related to the incidence of hantavirus disease. The disease is affected by climate and meteorological,environment, economic and social development, human life style and individual behaviors, etc.. Results from the analysis on main influencing factors and the nature of epidemics provide as with more evidence and information in setting up programs onto timely implementation of related prevention and control measures scientifically. By searching relevant scientific and technological literature, this paper summarizes the factors that affecting the nature of transmission and infection of hantavirus from related perspectives and factors including virus, host, climate and meteorological, meteorology, geographical environment, economic and social factors, etc.. In order to elaborate on the understanding of the epidemics and transmission characteristics of this kind of diseases, this paper provides evidence on prediction, prevention and control measures of hantavirus disease.

The outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 has rapidly spread globally. Cancer patients are at a higher risk of being infected with the coronavirus and are more likely to develop severe complications, as compared to the general population. The increasing spread of COVID-19 presents challenges for the clinical care of patients with gynecological malignancies. Concerted efforts should be put into managing gynecological malignancies in an orderly manner by strictly implementing the measures that are specifically developed for controlling the spread of COVID-19. We have drafted Recommendations on Management of Gynecological Malignancies during the COVID-19 Pandemic based on our experience on controlling COVID-19 pandemic in China. We recommend that patients with gynecological malignancies should be managed in hierarchical and individualized manners in combination with local conditions related to COVID-19. Medical care decision should be balanced between controlling COVID-19 pandemic spread and timely diagnosis and treatment for gynecologic oncology patients.

Objective: To systematically review the mortality burden study of influenza in mainland China. Method: "influenza", "flu", "H1N1", "pandemic", "mortality", "death", "fatality", "burden", "China" and "Chinese" were used as keywords, and a systematic literature search was conducted to identify articles in three English databases (PubMed, Web of Science and Embase) and three Chinese database (CNKI, WanFang and VIP) during 1990-2018 (excluding Hong Kong, Macao and Taiwan). The language of literature was restricted to Chinese and English. The inclusion criteria were human-oriented researches with method based on population, and research indexes included mortality and excess mortality. The exclusion criteria were non-primary research materials, predictive research and research on the burden of avian influenza related deaths. A total of 17 literatures were included, and the basic information to descriptive characteristics, methodology of modeling and the corresponding results were extracted. Results: All the 17 studies adopted indirect statistical models, with 14 of which adopted the regression model, and all the research index was excess mortality. All causes (16 studies), respiratory and circulatory diseases (14 studies) and pneumonia and influenza (10 studies) were the main causes of death associated with influenza. Influenza associated mortality burden in the elderly was higher, with the lowest excess mortality rates of all causes, respiratory and circulatory diseases, pneumonia and influenza being 49.57, 30.80 and 0.69 per 100 000 people, and the highest rates being 228.16, 170.20 and 30.35 per 100 000 people, respectively. In the non-elderly, the corresponding lowest rates were -0.27, -0.08 and 0.04 per 100 000 people respectively, and the highest rates were 3.63, 2.6 and 0.91 per 100 000 people, respectively. The influenza-related excess mortality was higher in the north, with a minimum of 7.8 per 100 000 and a maximum of 18.0 per 100 000, and slightly lower in the south, with a minimum of 6.11 per 100 000 and a maximum of 18.7 per 100 000. There were also differences in deaths caused by different influenza virus subtypes, with influenza A(H3N2) and influenza B virus possibly posing a heavier mortality burden. Conclusions Studies on influenza mortality burden is mainly based on indirect model and urban level in China. The mortality burden of influenza in the elderly, the northern and subtype A(H3N2) and B were more severe.

Objective To systematically review the mortality burden study of influenza in mainland China. Method "influenza","flu","H1N1","pandemic","mortality","death","fatality","burden","China" and"Chinese" were used as keywords, and a systematic literature search was conducted to identify articles in three English databases (PubMed, Web of Science and Embase) and three Chinese database (CNKI, WanFang and VIP) during 1990-2018 (excluding Hong Kong, Macao and Taiwan). The language of literature was restricted to Chinese and English. The inclusion criteria were human?oriented researches with method based on population, and research indexes included mortality and excess mortality. The exclusion criteria were non?primary research materials, predictive research and research on the burden of avian influenza related deaths. A total of 17 literatures were included, and the basic information to descriptive characteristics, methodology of modeling and the corresponding results were extracted. Results All the 17 studies adopted indirect statistical models, with 14 of which adopted the regression model, and all the research index was excess mortality. All causes (16 studies), respiratory and circulatory diseases (14 studies) and pneumonia and influenza (10 studies) were the main causes of death associated with influenza. Influenza associated mortality burden in the elderly was higher, with the lowest excess mortality rates of all causes, respiratory and circulatory diseases, pneumonia and influenza being 49.57, 30.80 and 0.69 per 100 000 people, and the highest rates being 228.16, 170.20 and 30.35 per 100 000 people, respectively. In the non?elderly, the corresponding lowest rates were-0.27,-0.08 and 0.04 per 100 000 people respectively, and the highest rates were 3.63, 2.6 and 0.91 per 100 000 people, respectively. The influenza?related excess mortality was higher in the north, with a minimum of 7.8 per 100 000 and a maximum of 18.0 per 100 000, and slightly lower in the south, with a minimum of 6.11 per 100 000 and a maximum of 18.7 per 100 000. There were also differences in deaths caused by different influenza virus subtypes, with influenza A(H3N2) and influenza B virus possibly posing a heavier mortality burden. Conclusions Studies on influenza mortality burden is mainly based on indirect model and urban level in China. The mortality burden of influenza in the elderly,the northern and subtype A(H3N2) and B were more severe.

Objective To systematically review the mortality burden study of influenza in mainland China. Method "influenza","flu","H1N1","pandemic","mortality","death","fatality","burden","China" and"Chinese" were used as keywords, and a systematic literature search was conducted to identify articles in three English databases (PubMed, Web of Science and Embase) and three Chinese database (CNKI, WanFang and VIP) during 1990-2018 (excluding Hong Kong, Macao and Taiwan). The language of literature was restricted to Chinese and English. The inclusion criteria were human?oriented researches with method based on population, and research indexes included mortality and excess mortality. The exclusion criteria were non?primary research materials, predictive research and research on the burden of avian influenza related deaths. A total of 17 literatures were included, and the basic information to descriptive characteristics, methodology of modeling and the corresponding results were extracted. Results All the 17 studies adopted indirect statistical models, with 14 of which adopted the regression model, and all the research index was excess mortality. All causes (16 studies), respiratory and circulatory diseases (14 studies) and pneumonia and influenza (10 studies) were the main causes of death associated with influenza. Influenza associated mortality burden in the elderly was higher, with the lowest excess mortality rates of all causes, respiratory and circulatory diseases, pneumonia and influenza being 49.57, 30.80 and 0.69 per 100 000 people, and the highest rates being 228.16, 170.20 and 30.35 per 100 000 people, respectively. In the non?elderly, the corresponding lowest rates were-0.27,-0.08 and 0.04 per 100 000 people respectively, and the highest rates were 3.63, 2.6 and 0.91 per 100 000 people, respectively. The influenza?related excess mortality was higher in the north, with a minimum of 7.8 per 100 000 and a maximum of 18.0 per 100 000, and slightly lower in the south, with a minimum of 6.11 per 100 000 and a maximum of 18.7 per 100 000. There were also differences in deaths caused by different influenza virus subtypes, with influenza A(H3N2) and influenza B virus possibly posing a heavier mortality burden. Conclusions Studies on influenza mortality burden is mainly based on indirect model and urban level in China. The mortality burden of influenza in the elderly,the northern and subtype A(H3N2) and B were more severe.

Objective To explore the perioperative outcomes and safety of enhanced recovery after surgery (ERAS) in laparoscopic radical cystectomy (LRC).Methods We retrospectively evaluated outcome of 10 LRC patients on ERAS protocol from May 2017 to October 2017,and 39 LRC patients on conventional recovery after surgery(CRAS) protocol from July 2015 to November 2016.There were (60.9 ±11.4) years and (63.7 ± 12.1) years in ERAS group and CRAS group respectively(P =0.514);(25.5 ±2.7) kg/m2 and (24.4 ± 3.6) kg/m2 with body mass index (P =0.375).Both of the median of charlson comorbidity index (P =0.931) and American Society of Anesthesiologists score (P =0.254) were 2 There was no statistical significance between the two groups for type of urinary diversion and preoperative laboratory studies (P ＞ 0.05).Patients' perioperative outcomes,early (30-day) complications and postoperative readmission rate were compared.Results The ERAS group had less intraoperative crystalloid infusion [(950.0 ± 474.3) ml vs.(1 797.4 ± 448.1) ml,P ＜ 0.001],faster removed gastric tube (0 d vs.4 d,P ＜0.001),and shorter passing flatus time [(1.6 ± 0.8) d vs.(2.9 ± 1.4) d,P =0.006] than the CRAS group;however,no difference was found in terms of intraoperative colliod infusion [(1 110.0 ± 331.5)ml vs.(1 117.9 ± 397.9) ml,P =0.954].No patients from either group required conversion to open surgery.There was no significant difference between the two groups for operative time (P =0.311),estimated blood loss (P =0.073),drain days (P =0.681),postoperative hospital stay (P =0.509),overall blood transfusion (P =1.000),intensive care unit stay (P =1.000) and tumor characteristics (pathological stage,histology,nodes removed,positive nodes,lymph node-positive patients,positive surgical margins).The 30-day postoperative complications were documented in 5 (50％)and 23 (59％)patients in groups ERAS and CRAS (P =0.878),respectively.And the most common complication were minor complications (Clavien-Dindo grade 1 and 2) in both groups (100.0％ vs.86.9％,P =0.729).The 30-day readmission rate was 20.0％ (2 patients) in ERAS group and 10.3％ (4 patients) in CRAS group with no statistical significance(P =0.588).Conclusions Our ERAS protocol expedited bowel function recovery after RC and urinary diversion without increasing in 30-day complications compared with CRAS.The key of implement ERAS pathway is to explore and develop their own protocol conformed to their medical treatment enviroment.

Objective To evaluate the effect of ulinastatin on postoperative cognitive dysfunction in preoperative sleep deprived aged rats.Methods Sixty clean healthy male Sprague-Dawley rats,aged 18 months,weighing 350-500 g,were divided into 3 groups (n=20 each) using a random number table:control group (group C),sleep deprivation group (group D) and ulinastatin group (group U).Sleep deprivation was induced by using modified multiple platform method in D and U groups,and then splenectomy was performed in three groups.Ulinastatin 100 U/g was intraperitoneally injected before sleep deprivation and immediately after operation in group U.Ten rats were randomly selected at 3 days after operation and sacrificed,and hippocampi were removed for determination of the contents of interleukin-1β (IL-1β),IL-6 and tumor necrosis factor-α (TNF-α) by enzyme-linked immunosorbent assay.Morris water maze test was performed at 3-7 days after operation in the rest ten rats in each group,and the escape latency and time of staying at the original platform were recorded.Results Compared with group C,the escape latency was significantly prolonged at 4-6 days after operation,the time of staying at the original platform was shortened,and the contents of IL-1β,IL-6 and TNF-α were increased at 3 days after operation in D and U groups (P＜0.05).Compared with group D,the escape latency was significantly shortened at 4-6 days after operation,the time spent in the original platform was prolonged,and the contents of IL-1β,IL-6 and TNF-α were decreased at 3 days after operation in group U (P＜0.05).Conclusion Ulinastatin can mitigate postoperative cognitive dysfunction in preoperative sleep deprived aged rats,which is related to inhibiting inflammatory responses.