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.

Objective To explore the diagnostic evidence and treatment strategies for steroid-resistant acute rejection (SRAR) after orthotopic liver transplantation.Methods A retrospective analysis was performed among 1038 patients undergoing orthotopic liver transplantation in our hospital from January 2004 to December 2013.A total of 169 acute rejection (AR) episodes occurred in 153 patients.Sixteen of the patients were diagnosed with SRAR because of no response to large-dose steroid pulse therapy.The diagnosis and treatment of the 16 patients were analyzed retrospectively.Comparison of data was made by x2 test or t test,and a P value of＜0.05 was considered to be significant.Results The incidence of AR after liver transplantation was 14.74％ (153/1038) in all the patients.The incidence of SRAR was 9.47％ (16/169) in patients with AR.In the 16 patients with SRAR,3 were treated with anti-CD3 monoclonal antibody (OKT3),9 were treated with monoclonal antibody against IL-2 receptor,and 4 received antithymocyte globulin (ATG) therapy.After treatment,SRAR was reversed in 12 of the 16 patients and caused death of the other 4 patients,yielding a reversal rate of 75％ and a mortality rate of 25％.Conclusion SRAR after liver transplantation has a low incidence rate but poor prognosis.The diagnosis of SRAR is mainly based on the clinical manifestation,laboratory test,liver biopsy,and poor response or rejection to methyl prednisolone pulse therapy.ATG and OKT3 achieve substantial outcomes in most of the patients in the treatment of SRAR.Particularly,compared with OKT3,ATG achieves a higher reversal rate and fewer adverse reactions,which is expected to become the first-line treatment of SRAR.

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.

Gefitinib is the well-tolerated first-line treatment of non-small cell lung cancer. As it needs analgesics during oncology treatment, particularly in the context of the coronavirus disease, where patients are more susceptible to contract high fever and sore throat.This has increased the likelihood of taking both gefitinib and antipyretic analgesic acetaminophen (APAP). Given that gefitinib and APAP overdose can predispose patients to liver injury or even acute liver failure, there is a risk of severe hepatotoxicity when these two drugs are used concomitantly. However, little is known regarding their safety at therapeutic doses. This study simulated the administration of gefitinib and APAP at clinically relevant doses in an animal model and confirmed that gefitinib in combination with APAP exhibited additional hepatotoxicity. We found that gefitinib plus APAP significantly exacerbated cell death, whereas each drug by itself had little or minor effect on hepatocyte survival. Mechanistically, combination of gefitinib and APAP induces hepatocyte death via the apoptotic pathway obviously. Reactive oxygen species (ROS) generation and DNA damage accumulation are involved in hepatocyte apoptosis. Gefitinib plus APAP also promotes the expression of Kelch-like ECH-associated protein 1 (Keap1) and downregulated the antioxidant factor, Nuclear factor erythroid 2-related factor 2 (Nrf2), by inhibiting p62 expression.Taken together, this study revealed the potential ROS-mediated apoptosis-dependent hepatotoxicity effect of the combination of gefitinib and APAP, in which the p62/Keap1/Nrf2 signaling pathway participates and plays an important regulatory role.