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In the context of the global pandemic of COVID-19, the epidemic intensity, epidemic characteristics and infection risk of influenza have presented new features. COVID-19 and influenza have simultaneously emerged in many regions of the world. COVID-19 and influenza are similar in terms of transmission mode, clinical symptoms and other aspects. There are also similarities in the mechanism of influenza virus and novel coronavirus on cells. At the same time, it is feasible and significant to do a good job in the prevention and control of COVID-19 and influenza. This paper discusses the relevant strategies and measures for the joint prevention and control of influenza and novel coronavirus from the aspects of influenza vaccination to prevent co-infection, simultaneous vaccination of influenza vaccine and novel coronavirus vaccine, etc., and puts forward corresponding thoughts and suggestions, in order to provide scientific support for the formulation of strategies on seasonal influenza vaccine and novel coronavirus vaccination.在新型冠状病毒肺炎（新冠肺炎）全球大流行的环境下，流感的流行强度、流行特征和人群的感染风险均呈现出新的特点，且全球多地区已出现新冠肺炎和流感共同流行的情况。新冠肺炎和流感的传播方式、临床症状等方面相似，流感病毒与新型冠状病毒对细胞的作用机制上也存在相似之处，同时做好新冠肺炎和流感的防控工作具有较强可行性和重大现实意义。本文从流感疫苗接种预防共同感染、流感疫苗和新冠病毒疫苗同时接种等方面，探讨了流感和新冠共同防控的相关策略和措施，提出了相应的思考和建议，以期为季节性流感疫苗和新型冠状病毒疫苗接种策略的制订提供科学支撑。.

This paper investigates the application of Laser beam prewelding/superplastic forming/diffusion bonding (LBW/SPF/DB) process in cylindrical parts. The forming die design and the processing process have been researched. A numerical simulation was carried out to determine the parameters of the superplastic forming/diffusion bonding process. The causes of defects are analysed and effective optimization methods are presented. In this paper, the main research contents are as follows, (1) Considering the characteristics of the structure and process of the workpiece, a design idea using a flapping tool and wedge fastening is presented. The process scheme for forming the core barrel step is described. (2) A laser welding power of 1300W and a welding rate of 1000mm/min were determined as the welding parameters for the SPF/DB process. The weld depth and weld width were considered suitable for parameters for laser welding. (3) The results of high temperature material performance indicate that 900 °C and a strain rate of 0.1s-1 strain rate were selected to simulate the forming process. (4) Verify the workpiece in accordance with the simulation parameters and evaluate defects, such as grooves on the surface of the workpiece and triangular areas between vertical bars. All the cylinders’ indexes can meet the requirements, and the process quality is stable and controllable.

Domestic and foreign literatures related to the persistence of SARS-CoV-2 and the re-positive cases infected with SARS-CoV-2 were reviewed, and the characteristics and infectivity of the re-positive cases were analyzed to provide scientific evidence for the improvement of case management and the development of measures to stop the spread of SARS-CoV-2. Existing studies have shown that re-positive rate of SARS-CoV-2 ranged from 2.4% to 19.8%, the median of interval between re-positive detection and discharge was 4-15 days. Following the second course of the disease, the anti-SARS-CoV-2 IgM, IgG and IgA positive rates of the cases were 11.11%-86.08%, 52.00%-100.00% and 61.54%-100.00% respectively, the total antibody and neutralizing antibody positive rates were 98.72% and 88.46%. The viral load of the re-positive cases was lower than that in the initial infection. At least 3 380 re-positive cases have been reported globally. SARS-CoV-2 strains were isolated from the samples of 3 re-positive cases (1 immunodeficiency case and 2 cases with abnormal pulmonary imaging). There were close contacts that were infected by an asymptomatic case taking immunosuppressive agents. In conclusion, the infectivity of re-positive cases infected with SARS-CoV-2 is generally very low. Rare re-positive cases infected with SARS-CoV-2 might cause further transmission. The management approach for the re-positive cases can be based on the assessment of the individual transmission risk according to the pathogen detection results.针对国内外新型冠状病毒（新冠病毒）感染者排毒持久性以及复检核酸阳性者的相关研究文献进行综述，分析复检阳性者的特征与传染性，为完善病例管理与预防新冠病毒传播措施的制定提供科学依据。现有研究结果显示，新冠病毒复检阳性率范围在2.4%~19.8%之间，复检阳性时间中位数为出院后4~15 d。复检阳性后新冠病毒特异性IgM、IgG和IgA抗体血清阳性率分别为11.11%~86.08%、52.00%~100.00%、61.54%~100.00%；总抗体和中和抗体的血清阳性率分别为98.72%和88.46%。复检阳性后病毒载量低于初次感染时的病毒载量。目前，全球至少报告了3 380例复检阳性者，有3例复检阳性者（1例免疫缺陷病例和2例肺部影像学异常病例）的标本中分离到具有传染性的活病毒，有1例应用免疫抑制剂的无症状感染者引起密切接触者感染。复检阳性者具有传染性的风险总体很低，极个别复检阳性者不排除引起续发传播的可能。对于复检阳性者的管理时间和管理方式，可基于病原检测结果对个体传播风险评估后进行确定。.

As the progress of population aging in China, the proportion of elderly population is increasing. Both chronic diseases and infectious diseases can threaten the health of the elderly. There are many kinds of infectious diseases, including vaccine preventable infectious diseases affecting the health of adults, such as influenza, pneumococcal diseases and herpes zoster. In addition, the newly emerged COVID-19 has caused a pandemic in the world, resulting the highest proportion of deaths occurred in the elderly and posing a serious threat to the health of the elderly. This paper mainly summarizes the prevention and control of vaccine preventable diseases and COVID-19 to which the elderly are susceptible, analyzes the infectious disease problems affecting the health of elderly population, and recommends countermeasures for the prevention and control of these diseases in elderly population.随着我国逐步步入老龄社会，老年人群占比越来越大，其健康受到慢性病和传染病的双重威胁。传染病种类繁多，针对成年人的重要疫苗可预防传染病有流感、肺炎球菌性疾病和带状疱疹等，另外新发传染病新型冠状病毒肺炎造成了全世界的大流行，死亡人群中老年人占比最高，对老年人的健康造成重大威胁。本研究主要针对老年人群的疫苗可预防疾病和新型冠状病毒肺炎进行概述，总结老年人群所面临的部分传染病问题，并提出防控建议。.

COVID-19 is an emerging infectious disease caused by SARS-CoV-2. After the infection of the virus, the host immune system is stimulated to produce multifarious specific antibodies to decrease or eliminate effects of the pathogen. Study of the specific antibodies dynamic characteristics in patients with COVID-19 is very important for the understanding and diagnosis of the disease, research and development of vaccine, and planning of prevention and control strategy. This paper reviews and summarizes the domestic and oversea research on dynamic characteristics of specific antibodies of COVID-19 patients, including the antibody producing, duration and level, and its possible influencing factors in order to improve the understanding of the immunological characteristics of COVID-19.新型冠状病毒肺炎是由新型冠状病毒（新冠病毒）引起的新发传染病。新冠病毒侵入人体后，刺激免疫系统产生多种特异性抗体，来减弱或清除病原体对机体的影响。研究新冠病毒感染后人体内特异性抗体动态变化特征对于疾病认识、诊断、以及疫苗研究与防控策略制定具有重要意义。本文对国内外关于新冠病毒感染者不同类型特异性抗体产生和持续时间、抗体水平及其可能的影响因素等方面的相关研究进行归纳分析，从而增进对新冠病毒感染后机体免疫学特征的了解。.

The studies on infectiousness of person infected with SARS-CoV-2 at different stages of illness are an important basis for making effective prevention and control measures such as investigating the infectious source, determining the scope of close contacts and the timing of case isolation. This review discusses the infectiousness of cases infected with SARS-CoV-2 in the incubation period, symptomatic period and convalescent period by reviewing national and international literatures, technical and professional guidelines. Existing researches suggest that the infectious viruses could be isolated at the end of the incubation period as well as since illness onset, and viral load in upper respiratory tract swabs reached the peak on day 4-6 after illness onset and thereafter began to decline, implying the infectiousness was relatively strong at the end of incubation period and within one week after illness onset. Although there were a few cases who tested positive for SARS-CoV-2 after recovery, no evidence was found to indicate these cases can cause the transmission.新型冠状病毒（新冠病毒）感染不同阶段的传染性特征是调查病例感染来源、确定密切接触者范围和病例隔离时间等防控措施的重要基础。本文通过对国内外文献、技术报告与专业指南等资料进行综述，基于病原学和流行病学两个维度的研究结果，探讨新冠病毒感染者在潜伏期、临床症状期和恢复期阶段的传染性特征。现有研究提示，新冠病毒感染者在潜伏期末和发病期均可分离到具有感染性病毒，发病4~6d后在上呼吸道样本中病毒载量达到高峰，随后开始下降，提示在潜伏期末和发病1周内的传染性相对较强。个别病例在恢复期尽管可再次检出新冠病毒核酸，但未发现具有传染性的证据。.

Multiple sensors in distributed attitude systems can be installed in different parts of the carrier, providing more information and introducing errors. Compared with the traditional attitude system, the common error sources of distributed attitude system sensors are installation error and inner lever arm error. In order to improve this problem, the installation error and inertial lever errors of distributed attitude system are analyzed and modeled. Simulation results are given. The results show that the installation error and the inner lever arm error have a great influence on the accuracy, which must be paid attention to in the practical application.

Bladder cancer is the most frequent tumor of the urinary system. Despite variety of new treatment options, bladder cancer remains a main global medical problem. Our purpose was to explore the potential molecular and therapeutic targets of bladder cancer diagnosis.The qRT-PCR was used to assess the expression of miR-20a in tissues and cell lines. Counting Cell Kit-8 (CCK-8) assay was carried out to evaluate cell proliferation. Cell migration was calculated using the transwell assay.The expression of miR-20a increased and PDCD4 decreased in bladder cancer tissues compared with normal tissues. Overexpression of miR-20a promoted T24 cell proliferation and migration, while miR-20a inhibitor suppressed cell proliferation and migration. MiR-20a targeted PDCD4 to regulate its expression in T24 cells. MiR-20a is inversely related to PDCD4 and PTENPL in bladder cancer tissues. Upregulation of PDCD4 suppressed T24 cell proliferation and migration.The PTENP1/miR-20a/PTEN axis was involved in the progression of bladder cancer. Our study investigated the function of miR-20a in bladder cancer and provided new insights into the treatment of bladder cancer.

In December 2019, novel coronavirus pneumonia epidemic occurred in Wuhan, Hubei Province, and spread rapidly across the country. In the early stages of the epidemic, China adopted the containment strategy and implemented a series of core measures around this strategic point, including social mobilization, strengthening case isolation and close contacts tracking management, blocking epidemic areas and traffic control to reduce personnel movements and increase social distance, environmental measures and personal protection, with a view to controlling the epidemic as soon as possible in limited areas such as Wuhan. This article summarizes the background, key points and core measures in the country and provinces. It sent prospects for future prevention and control strategies.2019年12月，湖北武汉市发生新型冠状病毒肺炎疫情，并迅速向全国蔓延。在疫情发生初期，我国采用围堵策略，并围绕此策略要点实施一系列核心措施，包括社会动员、加强病例隔离和密切接触者追踪管理、封锁疫区和交通管控以减少人员流动、增加人际距离、环境卫生措施以及个人防护等，以期尽快将疫情控制在武汉等有限地区。本文对围堵策略实施的背景、主要内容、以及核心措施进行了概述，分析了我国现阶段实施的围堵策略及核心措施的公共卫生意义，并基于措施效果的全面评价与疫情发展的态势评估提出下一步考虑建议。.

If the abdominal pedicled flaps are not well fixed after repair of deep electric burn wounds in hands, many problems such as poor blood supply may occur. In order to solve the above problems, we designed and manufactured the individualized low temperature thermoplastic plate combined with special abdominal band to fix abdominal pedicled flaps for repairing of 17 patients (12 males and 5 females, aged 2-35 years) with deep electric burn wounds in hands from February 2016 to August 2018, and achieved the desired results. The shoulder joint, elbow joint, and wrist joint were fixed by low temperature thermoplastic plate according to the 1/2 circumference of the patient's side chest and upper arm, and the braking of wrist joint and elbow joint was strengthened by special abdominal band. Application of the combined method of fixing abdominal pedicled flaps in repairing deep electric burn wounds in hands has high success rate of flap transplantation. It is simple to make and practical, and worthy of clinical promotion.腹部带蒂皮瓣修复手部深度电烧伤创面后若固定不佳，易出现血运不畅等诸多问题。为解决上述问题，笔者于2016年2月—2018年8月，自行设计、制作个体化低温热塑板结合特制腹带用于固定17例患者(男12例、女5例，年龄2～35岁)手部深度电烧伤创面的腹部带蒂皮瓣，达到预期效果。根据患者侧胸及上臂的1/2围径用低温热塑板设计、塑形，固定肩关节、肘关节、腕关节；再用特制腹带加固制动腕关节、肘关节。采用该联合方法固定修复手部深度电烧伤创面的腹部带蒂皮瓣，皮瓣移植手术的成功率高，且制作简单、实用性强，值得临床推广。.

We report the voltage regulation of electrodeposited elliptical magnetostrictive Ni nanodot arrays from single-domain to nonvolatile vortex state at room temperature. On the piezoelectric substrate, isolated elliptical Ni nanodots are fabricated between a pair of square electrodes, with the long axis parallel to the joint line of the electrodes. By applying a voltage to the surface electrodes pair, local stress is generated to induce the magnetization of the nanodots from single-domain to vortex state. The magnetization state of the nanodots is characterized by a magnetic force microscope. Even after the voltage is removed or applying another voltage, the nanodots maintain a stable vortex magnetization state, which shows that the vortex state after regulation is nonvolatile. These results are of great significance for the study of the low-energy-consumption regulation of the nano-dimensional magnetic material and vortex state-based nonvolatile memory.

Spin Wave (SW) has attracted great interest as information carrier in the past decades. Information transmission and processing between devices is achieved by collective precessional motion of magnetization without charge transfer, which enables lower energy consumption. In this paper, we perform several micromagnetic simulations to excite propagating spin wave and find that smaller external magnetic field can excite spin wave with shorter wavelength. A proper external magnetic(1800–2000mT) can excite spin wave with strong intensity for long-distance propagation. These findings will provide guideline in spin wave based logic devices design.

The spin torque nano-oscillator (STNO) with out of film plane fixed layer magnetization, namely the tilted-polarizer spin torque nano-oscillator (TP-STNO), has the advantage of microwave generation without the help of a magnetic field, which makes it promising to be integrated into a chip. In this paper, we present a thermal stability study of TP-STNO by macrospin modeling, in which the thermal noise is induced into the H eff of the Landau-Liftshitz-Gilbert-Slonczewski equation in the form of a stochastic magnetic field. The TP-STNO with different tilted angles is studied by numerical simulations based on the macrospin model and nonlinear system theory. Depending on the analysis of Lyapunov exponents as a function of drive current density in the room temperature range, we obtain the drive current density ranges in which TP-STNO can oscillate stably in the presence of thermal noise. These quantified results are essential during the practical usage of TP-STNO.

At present, the hypersonic vehicles cannot be adapted to all the flight phases perfectly, and the aerodynamic heating and lift - to - drag ratio are contradictory to the shape of the vehicles. From the perspective of aerodynamic heating, a blunt shaped body is desired to reduce the heat flow of the hypersonic vehicles. However, the lift - to - drag ratio demands a sharp leading edge. In this paper, a scheme of variable leading edge which could satisfy with both the requirements of aerodynamic heating and lift-to-drag ratio was investigated, and an adaptive thermal barrier was proposed based on the features of the variable leading edge hot structure. According to the heat flux calculated from a certain trajectory by computational fluid dynamics, the heat transfer behaviour of the variable leading edge with adaptive thermal barriers was analyzed by the finite element method. The results indicated that the temperature peak of the panel reached 1428.2 K at 400 s, temperature of the adaptive thermal barriers approached 1418.4 K at 420 s, and the temperature of the internal insulation increased to 667.86 K finally. At the end of trajectory, temperature distribution in the thermal barrier and internal insulation tended to be balanced respectively, which exhibited an excellent thermal property and a promising prospect in complex environment..

Patients with severe burn are characterized by strong oxidative stress and intense inflammatory response, which will cause metabolic disorder. Therefore, nutrition therapy is very important for severe burn. Nutrition therapy includes enteral nutrition (EN) and parenteral nutrition, and EN has the unique advantages. In recent years, more and more researchers focused on the EN for severe burn injuries, but there were still some confusing problems needing to solve. This article reviews the recent research about nutrition therapy for severe burn, including the route of feeding, energy requirements, and supplements of protein, carbohydrates, and microelements, and so on, so as to clarify some confusing questions about nutrition therapy for severe burn in clinical practice.

In order to determine whether tumor necrosis factor alpha inducible protein 3 (TNFAIP3) gene polymorphisms confers susceptibility to systemic lupus erythematosus (SLE) in ethnically different populations. A meta-analysis was conducted to examine the association between TNFAIP3 polymorphisms and susceptibility to SLE. A systematic literature search was conducted to identify all relevant studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of the association. A total of 23 studies from 20 articles, involving 18,501 patients with SLE and 30,435 healthy controls were included in this meta-analysis. Overall, we found significant association between SLE and the TNFAIP3 rs2230926, rs5029937, rs5029939, and rs3757173 polymorphisms (all P0.001). Stratification by ethnicity indicated that rs5029939 polymorphism was associated with SLE in Europeans, while rs2230926, rs5029937, and rs3757173 polymorphisms were associated with SLE both in Europeans and Asians (all P0.001). The results of our meta-analysis suggest that TNFAIP3 (rs2230926, rs5029937, rs5029939, and rs3757173) polymorphisms are associated with susceptibility to SLE.

In this article, a protective Ni–Co alloy coating was prepared on AZ91D magnesium alloy which was pretreated with electroless plating. The surface morphologies, microstructure and chemical composition of the coatings were studied using environmental scanning electron microscope, X-ray diffraction and energy dispersive spectroscopy respectively. The surface morphologies and microstructure analysis showed that the Ni–Co alloy coating possessed cone shaped grain congeries and formed face centred cubic solid solution. The energy dispersive spectroscopy analysis revealed that the content of cobalt element in the alloy coating was ∼31 wt-%. Potentiodynamic polarisation curves and electrochemical impedance spectroscopy were employed to investigate the corrosion resistance of different corrosive systems in neutral 3·5 wt-%NaCl and 0·5 mol L–1 Na2SO4 solutions, which were chosen to simulate the effects of marine and industrial environments respectively. The results showed that the corrosion resistance of t...

Aluminum-containing mesoporous molecular sieves (referred as WSAn, where n = Si/Al molar ratio = 50, 30 and 10) were synthesized via a surfactant templated approach by using fumed silica and aluminum sulfate as Si and Al precursors, respectively. When the 12-tungstophosphoric acid was grafted onto the surface of WSAn, a high dispersion of the heteropolyacid was achieved on the heteropoly compound/WSAn hybrid catalysts. The Keggin structure of the dispersed 12-tungstophosphoric acid was primarily preserved without destruction, but it was distorted in some degree, as confirmed by FTIR, 31P NMR-MAS and UV–vis spectroscopic characterizations. The surface Bronsted acidity of the catalysts was greatly enhanced by several times in comparison to that of the bare WSAn support. In the hydroisomerization reaction of n-heptane, the Pt/H3PW12O40/WSA30 catalyst exhibited the highest catalytic activity and the best isomerization selectivity among the catalysts tested, which can be generally correlated with its large number of Bronsted acid sites and high structural regularity. After the n-heptane hydroisomerization reaction, a high molar ratio of multibranched to monobranched isohexanes was obtained, indicating that Pt-promoted heteropoly compound/WSAn hybrid catalysts have a great potential for the hydroisomerization of long carbon chain hydrocarbons.

In recent years, mutations in glucocerebrosidase gene (GBA), which encodes the lysosomal enzyme glucocerebrosidase (GCase) deficient in Gaucher disease (GD), were found to be the most widespread genetic for the development of Parkinson disease.In this work, we investigated the possibility of a biological linkage between GCase and alpha-synuclein.siRNA was used to knockdown the GBA, then the related proteins such as alpha-synuclein were detected, additionally, the mutations of GBA were also detected. We also provide evidence that a mouse model of Gaucher disease (GBAD409H/D409H) to detect the gene types of GBA.The results showed functional knockdown (KD) of GBA in neuroblastoma cells culture causes a significant accumulation of alpha-synuclein and alpha-synuclein-mediated neurotoxicity. Furthermore, KD of GBA in rat primary neurons expressing the A53T mutation of alpha-synuclein, decreases cell viability. In addition, we observed that overexpression of several GBA mutants (N370S, L444P, D409H, D409V) significantly raised human alpha-syn levels of vector control. Glucosylceramide (GlcCer), the GCase substrate, influenced formation of purified a-syn by stabilizing soluble oligomeric intermediates. We also provide evidence that a mouse model of Gaucher disease (GBAD409H/D409H) exhibited alpha-syn aggregates in substantia nigra, cortex and hippocampus regions. ELISA analysis showed a significant rise in membrane-associated α-syn and western blot analysis showed that two forms of alpha-syn oligomers were present in brain homogenates from the hippocampus D409H mice.These studies support the contention that both WT and mutant GBA can cause Parkinson disease-like alpha-synuclein pathology.

The most important thing facing all levels of government after an earthquake is to do everything possible to rescue injured people and evacuate those who are in the dangerous area to the safe places as soon as possible. What kinds of shelters are selected to be appropriate as earthquake shelters? This is an issue that emergency management agencies have to deal with. For this reason it is necessary to set an evaluation model for earthquake emergency shelter (EES) so as to provide groundwork for decision making in the selection of earthquake emergency shelters. The objective of this study focuses on establishing a comprehensive evaluation model for the selection of earthquake emergency shelters. A total of three evaluation indicators are picked up: capacity of shelter, quality of facility, and accessibility. The definitions and quantitative calculation procedure of these indicators are elaborated. The weight of each indicator is estimated based on Analytic Hierarchy Process (AHP). A case study is also conducted to substantiate the validity and usefulness of the model. The results of this study can provide technical support in the selection of shelters for earthquake.

To investigate the role of overexpression of Bak in apoptotic pathways and drug susceptibility using doxorubicin and vinorelbine in human HCC-9204 cells.An inducible system, MT-II regulatory system which allowed controlled expression of protein upon addition of ZnSO4(100 mumol/L) as an external inducer was used. Stable transfection of pMD-Bak gene was performed on HCC-9204 cells. Apoptotic cells were measured by morphological criteria, as well as by TUNEL assay and flow cytometry. The ability of Bak to decrease clonogenic cell survival was studied by colony-forming assays, while decrease in cell viability was assessed by MTT assay.Cells overexpressing Bak showed extensive cell death with nucleus fragmentation detected by TUNEL assay. FACS analyses showed that Bak could induce significant G1 accumulation and apoptosis in 19.29% cells 24 h after induction. Bak significantly decreased the clonogenic survival following exposure to adriamycin, but not vinorelbine. Furthermore, the time-course of cell viability rates following exposure of HCC-9204/Bak cells to adriamycin and vinorelbine was in agreement with the above findings. Bak selectively sensitized HCC-9204 cells to death induced by adriamycin while resisted to vinorelbine.Bak may prolong cell cycle in G1 phase, leading to apoptosis and decrease clonogenic survival of HCC-9204 cells in a drug-specific manner.

This paper gives an overview of new ICRF techniques developed on HT-7 superconducting tokamak during 1998 campaign, using the present two simple loop antennas, for wall conditioning/boron film deposition of the vessel and start-up of OH discharges: (1) The results show that He-plasma is reliably produced at the standard ICRH frequency (f=22.5 MHz), in a wide range of toroidal field, gas pressure and different RF power level. ICRF cleaning efficiency is about three times higher than that of glow discharge cleaning, this new technique has been used daily during experiments. (2) Start-up experimental results show that RF power was very effective to make the breakdown time less than 2 ms and helpful to assist the plasma start-up when the ICRF power reached 50 kW level. About 10%–20% reduction in the volt-second consumption was achieved according to different condition, evaluated at the beginning of the current flattop. (3) Boronization is carried out by using IBW antenna, the film depth is about 350 nm, and i...

Chronic cervicitis was shown to be related to papillomavirus type 16(HPV-16), herpes simplex virus type 2 and cytomegalovirus (CMV) infections as demonstrated by DNA hybridization technique and virus isolation method from samples taken from erosive and normal cervices. After one course of treatment with recombinant interferon alpha 1 (rIFN-alpha 1), 93.8% of cases showed clinical improvement and 60% marked improvement. The HPV-16 and HSV detection rates dropped down significantly after rIFN-alpha 1 treatment as compared with those before treatment. Astragalus membranaceus, a Chinese herbal drug, was shown to be synergic to interferon therapy.

Summary HindIII fragments D to P of DNA from a Chinese vaccine strain (Tian Tan) of vaccinia virus have been molecularly cloned into the plasmid pAT153 at the unique HindIII site. The Chinese strain DNA differs from a non-vaccine American strain (WR) in having an additional HindIII fragment (P). Twelve HindIII D clones and 12 HindIII F clones of the Chinese strain were analysed by digestion by EcoRI, BamHI, PstI and XhoI. Two forms of D (designated a and b) and of F (a and b) were demonstrated. In each the differences were detected as the presence of an additional EcoRI site, in Da and Fa. The HindIII Fa and Fb fragments of the Chinese strain were shown to differ significantly from the WR strain in their restriction site maps.