The present paper analyzes common mistakes in exemplification in the writing part of Band 4 College English Test.It discusses pertinence,appropriateness,typicality,logic and novelty of exemplification instead of dwelling on mistakes in spelling,wording and grammar,and offers some practical strategies of exemplification.

To construct a library of mouse single chain variable fragment (scFv) antibody against ofloxacin using phage display and recombinant antibody technique, specific anti-ofloxacin scFv was screened and 3D structure was homology modeling. Total RNA was extracted from hybridoma cell of ofloxacin mAb, and was used to amplify VH and VL gene by RT-PCR using random primer. Then they were linked by a DNA linker encoding (G1y4 Ser) 3 as VH-linker-VL sequence forming scFv by SOE(splicing by overlap extension) PCR. These fragments were inserted into phage T7 after double digestion and transformed with host bacteria BLT5403. 3 ×105 pfu / ml single chain antibody phage libraries were successfully constructed. Four positive phage scFv clones were screened by direct competitive ELISA after four times of enriched procedure in the order of adsorption-elution-amplificatio, 3D structure of specific scFv was homology modeling finally. This research lays a foundation for further massive expression of anti-ofloxacin scFv.

OBJECTIVE:To provide reference for rational use of Shexiang tongxin dripping pills in clinic. METHODS:In retrospective study,the utilization of Shexiang tongxin dripping pills in outpatients and inpatients of our hospital during Jan. 2014-May 2015 was analyzed statistically in terms of gender,age,department,irrational drug use,ADR and DUI,etc. RE-SULTS:There were 719 outpatient prescriptions and 281 inpatient medical orders. The female was more than male with ratio of 1.42:1. Most patients aged 80-89 year-old(35.4%). Shexiang tongxin dripping pills were mostly used in cardiovascular medicine de-partment(760 pieces/copies,76.0%). There were 72 prescriptions/medical orders that did not conform to the indications(7.2%), and 7 prescriptions/medical orders for overdose use(0.7%). No obvious ADR was found. DUI of Shexiang tongxin dripping pills was 1.007. CONCLUSIONS:Although the clinical use of Shexiang tongxin dripping pills in our hospital is basically rational,there still are some nonstandard uses,which should be taken seriously. In order to reduce ADR,the clinical use of Shexiang tongxin dripping pills should be strictly in accordance with the drug instructions and should emphasize the syndrome differentiation based on treatment.

Objective To identify the Banna viruses isolated in northwestern part of Yunnan prov-ince in order to make the difference clear between the isolates and other Banna viruses isolated in other parts of Yunnan. Methods Three isolates of Banna vires isolated in 2005 and 2006 were identified by morpholo-gy, RNA-PAGE profile and molecular biologic method. Nueleotide and amino acid sequences of segment 12 of the 3 isolates were sequenced and analyzed. Results Three Banna viruses were isolated from mosquitoes collected in northwestern part of Yunnan during 2005 and 2006. Electron microscopy study showed that they are spherical with a diameter of 70 nm, no envelope but two layers of eapsid. It was found that the genome of the 3 isolates composes of 12 segments presenting band profile of 6-6 in RNA-PAGE. Nueleotide acid se-quence analysis about segment 12 showed that the identity was 99% between the 3 new isolates, 98% and 90% between the 3 isolates and the strains isolated in other parts of Yunnan, China and Indonesia, respec-tively. Phylogenetie analysis based on segment 12 gene showed that 3 new isolates clnstered in the same branch with the viruses isolated in other parts of Yunnan. The same difference of amino acids was found between Banna viruses isolated in China and Indonesia strains in the analysis of segment 12. Conclusion Banna virus strains were firstly isolated from mosquitoes collected in northwestern part of Yunnan province. Nueleotide acid sequence analysis of the 3 new isolates showed higher identity with strains isolated in other parts of Yunnan.

Nerve growth factor (NGF) promotes neuronal survival and differentiation and stimulates neurite outgrowth. NGF is synthesized as a precursor-proNGF in vivo. In this paper, a pET-proNGF prokaryocyte expression vector was constructed and transformed into E. coli BL21(DE3)pLysS. The proNGF was expressed in the form of non-active aggregated monomer in E. coli after induction with IPTG. SDS-PAGE revealed the proNGF expression product had a Mr.30.2 kD. Western blotting analysis showed that the protein had good antigenicity. Fusion protein was successfully purified by Ni2+-NTA affinity chromatography and cleaved by Enterokinase and 13.1 mg proNGF was obtained from 100 mL cell culture in a typical experiment. The protein was dialyzed in a redox system containing reduced and oxidized glutathione. RP-HPLC was used to analysis the result of the refolding. The refolded proNGF protein can induce neurite outgrowth of PC12 cells, which indicated that pro-form of NGF we obtained had biological activity.
Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; genetics ; Humans ; Nerve Growth Factor ; biosynthesis ; genetics ; Protein Precursors ; biosynthesis ; genetics ; Protein Renaturation ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; isolation & purification

Objective To explore the optimized method of venous anastomosis for right donor kidney transplantation in rats.Methods Sprague Dawley (SD) rats were used as donors and recipients for homologous rat kidney transplantation.Both bilateral kidneys were harvested from the donor rats (n =45).Ninety rats were used as recipients and divided into 4 groups according to randomly digital table:In groups AC (n =15 each),the right donor kidneys were transplanted into the left nephridial pit of recipients,and endto-side,venous bypass and modified end-toend (donor's proximal end of vena cava was anastomosed to recipients renal Vein followed by ligation of its distal end) venous anastomosis was done,respectively; In the control group (n =45),the left donor kidneys were transplanted into the same side of the recipients,and the conventional end-to-end venous anastomosis was used.Then the intra-operative findings,successful operation rate and postoperative complications were compared between two groups.Results The venous anastomosis time in group B was longer than in groups A,C and control group (P＜0.05),which significantly increased warm ischemia time of donor kidneys and operative time of recipients (P＜0.05).The venous anastomosis time,warm ischemia time of donor kidneys and operative time of recipients showed no significant difference between groups A or C and control group (P＞0.05).The successful operation rate in group C (93.3％)was similar to that in control group (86.7％) (P＞0.05),but higher than in group A (53.3％) and group B (53.3％) (P＜0.05).There was no significant difference in postoperative complications between group A and group C.Conclusion For right donor kidney transplantation,the method of harvesting the right donor kidney with a part of vena cava,and then anastomosing the proximal end to recipients renal vein and ligating the distal end,is highly feasible,efficient and economic.

Objectives To research clinical effects of severe brain injury patients treated by acupuncture and herb combine mild hypothermia,discuss the new approach of severe brain injury patients treatment combine Chinese traditional and Western medicine.Methods Investigated 68 severe traumatic brain injured patients,randomly divided into three groups,acupuncture and herb combine mild hypothermia group (n =22),mild hypothermia group (n =24) and normal temperature routine treatment group (n =22).Dynamic intracranial pressure,brain damage index (cytoskeletal protein),immunologic function (IL-6,β2 microglobulin),combine rate of complications (including irritable ulcer,lung infection,epilepsy,sugar metabolism disorder,and so on),and long-term GOS score were analyzed.SPSS12.0 software was used for statistical processing,and the standard deviation of the measurement data were expressed as the standard deviation.The counting data were expressed as apercentage,and the chi-square test was used for the comparison between group.Results There were significant differences between three groups of intracranial pressure,immunologic function,complication occurring rate (P ＜0.05),but there had no significant difference between acupuncture and herb combine mild hypothermia group and mild hypothermia group of brain damage index and GOS,and there have significant difference between these two groups and normal temperature routine treatment group.Conclusions Acupuncture and herb combined mild hypothermia might be better in reducing intracranial pressure,the incidence of complication,and improving immune function of severe brain injury,than mild hypothermia group and normal temperature routine treatment group.

Objective:To summarize the clinical characteristics of patients with epilepsy caused by focal cortical dysplasia (FCD), and identify the influencing factors for postoperative seizure controls.Methods:Fifty-seven patients with epilepsy caused by FCD admitted to Department of Neurosurgery, Third Affiliated Hospital of Zhengzhou University from July 2019 to November 2023 were chosen; standard preoperative evaluation, surgery, postoperative management and follow-up were performed. A retrospective study of clinical data, imaging and video electroencephalogram (VEEG) data, surgical approaches, pathological findings, and follow-up data was performed; influencing factors for postoperative seizure controls were analyzed.Results:In these 57 patients with epilepsy caused by FCD, 29 were males (50.88%) and 28 were females (49.12%). Onset age was 30.00 (8.00, 74.50) months, and surgery age was 95.00 (50.00, 138.50) months. Focal to bilateral tonic-clonic seizures (42/57; 73.68%) and epileptic spasms (13/57; 22.81%) were common seizure types. Cranial MRI was positive in 34 patients (59.65%), mainly manifested as abnormal cortical gyri/sulci morphology (17/57; 29.82%). In 43 patients accepted PET-CT, hypometabolic sites were detected in 40 (93.02%), and complete agreement between PET/MRI fusion results and actual lesion sites was noted in 40 (93.02%). FCD type I was noted in 16 patients (28.07%), type II in 39 (68.42%), and type III in 2 (3.51%). By December 2023, 44 (77.19%) had Engel grading I, 4 (7.02%) had grading II, 4 (7.02%) had grading III, and 5 (8.77%) had grading IV. Children with good prognosis (Engel grading I+II) and those with poor prognosis (Engel grading III+IV) showed significant differences in terms of time from first seizure to surgery, positive/negative MRI, and regularity of postoperative ASMs ( P<0.05). Conclusions:Focal to bilateral tonic-clonic seizure is the most common seizure type in patients with epilepsy caused by FCD, and abnormal cortical gyri/sulci morphology is the most common MRI manifestation; PET/MRI fusion imaging is superior to PET-CT or MRI in identifying epileptogenic foci. Poor seizure control can be noted in patients with long onset time to surgery, with negative cranial MRI results, or with irregular postoperative ASMs.

Blood-retina barrier destruction, nerve injury, formation of neovascularization and fibroblast proliferation membrane are important pathological changes of DR, which are related to the combined effects of various vitreous cytokines. VEGF is mainly involved in increasing retinal vascular permeability and inducing neovascularization. Pigment epithelium derived factor is vital reducing vascular permeability and neuroprotection; IL plays a key role in mediating inflammatory response. TNF-α is related to inflammation, which is significantly up-regulated by hypoxia. TGF-β is an important cytokine regulating cell proliferation and differentiation. Connective tissue growth factor can promote the growth, migration and adhesion of endothelial cell. In addition, many other molecular mechanisms have not been fully elucidated, and further study on the molecular mechanism of DR is urgent. With the further study of molecular mechanism, the early intervention and targeted treatment of DR will be more effective.

The condition of patients with severe traumatic brain injury (sTBI) complicated by corona virus 2019 disease (COVID-19) is complex. sTBI can significantly increase the probability of COVID-19 developing into severe or critical stage, while COVID-19 can also increase the surgical risk of sTBI and the severity of postoperative lung lesions. There are many contradictions in the treatment process, which brings difficulties to the clinical treatment of such patients. Up to now, there are few clinical studies and therapeutic norms relevant to sTBI complicated by COVID-19. In order to standardize the clinical treatment of such patients, Critical Care Medicine Branch of China International Exchange and Promotive Association for Medical and Healthcare and Editorial Board of Chinese Journal of Trauma organized relevant experts to formulate the Chinese expert consensus on clinical treatment of adult patients with severe traumatic brain injury complicated by corona virus infection 2019 ( version 2023) based on the joint prevention and control mechanism scheme of the State Council and domestic and foreign literatures on sTBI and COVID-19 in the past 3 years of the international epidemic. Fifteen recommendations focused on emergency treatment, emergency surgery and comprehensive management were put forward to provide a guidance for the diagnosis and treatment of sTBI complicated by COVID-19.