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A pressure test of muzzle shock wave is carried out to understand the propagation of muzzle shock wave in low pressure environment. Low pressure environment is established in a cabin through vacuum pumping system. Pressure curves of muzzle shock wave at different pressures are got by the pressure test system. The results show that the distribution of muzzle shock wave in low pressure environment is the same as that in atmospheric environment. With the decrease in the ambient pressure, the intensity of shock wave decreases linearly. The intensity of shock wave at 10 km altitude is roughly half of that in ground. These results lay the foundation for the research on muzzle flow field and its control technology of aircraft gun in real high altitude environment. [ABSTRACT FROM AUTHOR]

Objective: To study the toxicity changes of different proportions of Radix Adenophora, Radix Glehniae combined with Veratrum nigrum L., thus providing acute toxicity data and investigating whether decoction factors were correlated with toxicity., Methods: The uniform design method was used by two factors and seven levels to investigate the toxicity changes in different proportions of Radix Adenophora, Radix Glehniae combined with Veratrum nigrum L. The decoction factors were also investigated., Results: The compatibility toxicity was affected mainly by Veratrum nigrum L. and the toxicity increased along with increased doses of Veratrum nigrum L. The toxicity of co-decoction was higher than mixed decoction in the same dosage of Radix Glehniae and Veratrum nigrum L. The promotion of the dissolution of the toxic component of Veratrum nigrum L. in co-decoction may be the cause of the higher toxicity., Conclusion: Radix Adenophora and Radix Glehniae combined with Veratrum nigrum L. resulted in higher toxicity, which indicated that the incompatibility between Radix Adenophora, Radix Glehniae, and Veratrum nigrum L. In clinic practice, a prescription contained these drugs should be avoided.

Objective: To observe the effect of tanshinone IIA (TS IIA) pretreatment on the expression of the inflammatory factor IL-1β and RelA mRNA in rats with focal cerebral ischemia., Methods: A total of 100 adult male SD rats were randomly divided into 6 groups, namely the model, ischemic preconditioning (IPC), TSIIA preconditioning, TSIIA treatment, sham-operated, and blank control groups. In the former 4 groups, rat models of focal cerebral ischemia were established with corresponding treatments. The expressions of IL-1β and RelA mRNA in each group were detected using RT-PCR., Results: All the groups showed expressions of IL-1β and RelA mRNA with the exception of the blank control group. Compared to the model group, TSIIA preconditioning group, TSIIA treatment group, and IPC group all had significantly reduced expression of IL-1β and RelA mRNA (P < 0.05). The expressions were lower in IPC group than in TSIIA preconditioning group and TSIIA treatment group(P < 0.05), and no significant difference was found in the expressions between the latter two groups., Conclusion: The protective effect of pretreatment with TS IIA against cerebral ischemia is related to the reduction of IL-1β and RelA mRNA expressions.

Objective: To investigate the relationship between the distribution of mononucleotide polymorphism of five regulation regions of alpha-IFN among HLA-DRB1*11 gene episodes and the therapeutic effects of alpha-IFN treatment in chronic hepatitis B patients., Methods: One hundred seven chronic hepatitis patients from Nanjing Second Hospital who were treated by alpha-IFN for 12 months and then followed at least six months without the treatment were randomly selected for this regressive analysis. They were grouped into a continuous responsive group and a non-continuous responsive group. Hepatitis B virus X interacting protein gene locus was searched in NCBI. Single nucleotide polymorphism (SNP) gene locus was detected based on a pooling sequencing method. Primer and TaqMan-MGB probes referring to different mononucleotide loci were designed respectively to detect SNP in five regulation regions of alpha-IFN. Then gene sequencing differences between the two groups were analyzed., Results: Among the 107 cases there were 30 cases (28.0%) in the continuous responsive group and 77 cases (71.9%) in the non-continuous responsive group. CT occupation rate in five regulation regions of IFN reached 18.0% in the continuous responsive group and 23.8% in the non-continuous responsive group. AG occupation rate reached 10.8% in the former group and 15.8% in the latter group. The differences in CT and AG between the two groups were significant., Conclusions: The distribution of mononucleotide polymorphism of five regulation regions of alpha-IFN among HLA-DRB1*11 gene episodes affects the IFN anti-virus treatment. Detecting the gene distribution of mononucleotide in five regulation regions of alpha-IFN helps in predicting the therapeutic effects of alpha-IFN.

Objective: To study the content variation of furmarid acid and isofraxidin in Sarcandra glabra from 21 different provenances and provide the basis for resource utilization and quality optimization of S. glabra., Method: HPLC method was developed to determine the contents of furmarid acid and isofraxidin in 330 samples of S. glabra which were collected respectively from 21 different provenances., Result: There were significant differences in the contents of isofraxidin and furmarid acid in S. glabra from different provenances. The contents of isofraxidin and furmarid acid dropped off from low altitude to high altitude, which were also close with longitude and latitude. The content of isofraxidin in S. glabra at central area of natural distribution was the highest. The different parts of the plant had different results, the influence on the contents of the acitive components in stem were more obvious than the leaf., Conclusion: This simple, accurate and reproducible method could be use to determine the contents of furmarid acid and isofraxidin in S. glabra. The results represented the status of medicines quality and difference of Chinese S. glabra. These agreed with the traditional views that the medicines quality of Sarcandra glabra in Jiangxi, Fujian, Zhejiang was better. These provenances were considered as important areas of medicines breeding and bases building on S. glabra in future.

Objective: To investigate the possible association between the glutamate-cysteine ligase catalytic subunit gene (GCLC) C-129T and modifier subunit gene (GCLM) G-23T polymorphisms with coronary heart disease (CHD) in Chinese population., Methods: GCLC C-129T and GCLM G-23T genotypes were determined in 212 CHD patients and 218 healthy individuals using a PCR-based restriction fragment length polymorphism (RFLP) method. Odds ratio (OR) for CHD and 95% confidence interval (CI) from unconditional logistic regression models were used to evaluate relative risks., Results: The T allele of the GCLC C-129T polymorphism was more frequently found in CHD cases than in controls (P < 0.01) and individuals with GCLC-129T allele had a significantly higher risk for CHD (OR = 2.38, 95% CI: 1.25 - 4.54) as compared to individuals with the -129C allele. When compared with CC homozygote, CT heterozygote had a 2.14-fold higher risk for CHD (95% CI: 1.08 - 4.24, P < 0.05) and carriers of the-129T allele (CT or TT genotype) also had a similarly 2.28-fold higher risk for CHD (95% CI: 1.16 - 4.49, P < 0.05). In contrast, the frequency of T allele of the GCLM G-23T polymorphism was lower in CHD patients than that of controls (0.174 vs. 0.264) and individuals with the GCLM-23T allele had a significantly lower risk for CHD (OR = 0.59, 95% CI: 0.42 - 0.82, P < 0.01) as compared to the -23G allele. When compared with GG homozygote, the OR of CHD for GT heterozygote was 0.71 (95% CI: 0.47 - 1.08, P > 0.05), for TT homozygote was 0.18 (95% CI: 0.06 - 0.55, P < 0.01), and for carriers of the -23T allele (GT or TT genotype) was 0.61 (95% CI: 0.42 - 0.92, P < 0.05)., Conclusion: The GCLC C-129T polymorphism may be one of the genetic risk factor while the GCLM G-23T polymorphism may be one of the genetic protective factors for CHD in this Chinese population.

Objective: To investigate the association between the single nucleotide polymorphisms (SNPs) in TP53 gene and susceptibility to colorectal cancer (CRC) in Chinese population., Methods: Peripheral blood samples were collected and white cell genomic DNA was extracted from 345 CRC patients, 198 males and 1447 females, aged (58.7 +/- 13.5), and 670 sex, age, smoking and drinking situations-matched controls in Ningbo city, Zhejiang province The genotypes of the SNPs of C-8343G, C-1863T, and R72P in TP53 gene were determined by either TaqMan assays or PCR-based restriction fragment length polymorphism method. Unconditional logistic regression was used to calculate the odds ratio (OR) for CRC after adjustment of the covariates, such as sex, age, cigarette smoking, alcohol drinking, body mass index and first-degree family history of CRC, and 95% confidence intervals (CI) so as to evaluate relative risk., Results: There were not significant differences in the above mentioned covariates between these 2 groups. No significant association of C-8343G or C-1863T polymorphism with CRC risk was observed (both P > 0.05). The CRC risk of the 72P genotype was 50.3%, 1.53 times that of the 72R genotype (39.6%) (95% CI = 1.27 - 1.85, P < 0.01). The CRC risk of the RP heterozygotes was 1.60 times that of the RP homozygote (95% CI = 1.17 - 2.18, P < 0.01), and the CRC risk of the PP homozygotes was 2.37 times that of the RP heterozygotes (95% CI = 1.61 - 3.47, P < 0.01). A dose-response relationship was shown (P < 0.01). Stratified analysis indicated that the 72P allele conferred a more pronounced increase in CRC risk among the alcohol consumers: the CRC risk was 3.01 times for the RP heterozygotes (95% CI = 1.48 - 6.12), and 4.71 times for the PP homozygotes (95% CI = 1.90 - 11.68)., Conclusion: TP53 C-8343G and C-1863T polymorphisms are not associated with CRC risk. R72P polymorphism contributes to the etiology of CRC in the Chinese population, particularly among the alcohol consumers.

Objective: To investigate gene mutations of the epidermal growth factor receptor (EGFR) and K-RAS in Chinese non-small cell lung cancers (NSCLCs)., Methods: Mutations of exons 18, 19 and 21 of the EGFR and codons 12, 13 of the K-RAS in 101 NSCLCs were detected by PCR-amplifying and gene sequencing, and the relationship between mutations and clinical characters of NSCLCs and response to gefitinib were analyzed., Results: Overall, 26 EGFR mutations (25.7%), 3 K-RAS mutations (2.9%) were detected, and EGFR mutation frequencies in adenocarcinomas, nonsmoker and female were found to be high (44.2%, 65.7% and 48.3% respectively). Nine out of 10 gefitinib treated patients with disease control was found with EGFR mutation., Conclusion: The data suggest that mutation frequency of EGFR in NSCLCs from Chinese patients is higher than that of western ethnicities, such mutations are well correlated with tumor response to gefitinib, and gefitinib is more fit for Chinese NSCLC patients.

Objective: To evaluate the enhancing effects of ginsenoside Rg3 combined with mitomycin C and tegafur (MF) on postoperative chemotherapy in advanced gastric cancer., Methods: Seventy-one postoperative patients with advanced gastric cancer were randomly divided into two groups, the control group (n=33), which received treatment with only MF (Mitomycin C+Tegafur), and the trial group (n=38), which were treated with ginsenoside Rg3+MF. The serum VEGF levels in the control group and trial group were detected preoperatively and postoperatively, meanwhile, the serum VEGF levels in 30 healthy persons were detected as comparison. The relations between patients survival and serum VEGF levels were analyzed., Results: The levels of serum VEGF in advanced gastric cancer were higher than those in healthy persons [(297.8+/-129.6) pg/ml vs (212.3+/-67.5) pg/ml] (P<0.01), and were correlated with the depth of tumor invasion, lymph node metastasis, tumor size > 4 cm and TNM stage (P<0.05). Fourteen weeks after operation, the levels of serum VEGF in trial group decreased below those of preoperation and approached to normal range, while in the control group, the levels of serum VEGF decreased near those of preoperation only. The median survival of patients in trial group and control group were 40 and 25 months respectively. The survival rate of patients in trial group was significantly higher than that in control group (P=0.047)., Conclusion: The combined application of ginsenoside Rg3+MF chemotherapy can decrease the concentration of serum VEGF and improve the survival rate in advanced gastric cancer patients.

Objective: To explore the clinical characteristics,diagnosis and treatment of abdominal cocoon., Methods: Clinical data of 203 cases with abdominal cocoon including 7 cases in our hospital and 196 cases reported in Chinese literature from January 1995 to June 2005 were analyzed retrospectively., Results: The male to female ratio was approximately 1.2:1. The mean age at diagnosis was 33 years. The main clinical manifestations included recurrent acute or chronic intestinal obstruction in 147 cases (72.4%), abdominal mass in 53 cases (26.1%). Of the 203 cases, abdominal plain X-ray were performed in 163, B-ultrasound in 85, CT in 68 and barium meal in 32 cases, however, only 6 cases (3.0%) were diagnosed as abdominal cocoon preoperatively. All the cases received operations included partial or total excision of the membrane and enterolysis in 172 cases (84.7%), together with bowel resection in 34 cases (16.7%) and appendectomy in 51 cases (25.1%). Postoperative complications included recurrent obstruction in 55, and death in 11 cases (5.4%)., Conclusions: The preoperative diagnosis of abdominal cocoon is difficult. Operations should be performed on the cases with intestine obstruction. Recurrent adhesive intestinal obstruction is the main postoperative complication.

Objective: A functional single nucleotide polymorphism (SNP) at codon 72 of the gene for p53 protein (p53 R72P) has been implicated in a variety of human cancers, but the relationship between this SNP and hepatocellular carcinoma (HCC) remains obscure despite the fact that the critical role of p53 protein in HCC has been documented. This study was conducted to evaluate the link between the polymorphism with HCC stratified by chronic hepatitis B infection status in a Chinese population., Methods: Four hundred and sixty-nine HCC cases (359 HbsAg-positive, 110 HbsAg-negative) and 567 controls (137 HbsAg-positive, 430 HbsAg-negative) were studied. The p53 genotypes were determined by a PCR based restriction fragment length polymorphism (RFLP) method., Results: Overall, no correlation between HCC and the R72P genotypes was found when comparing all cases to controls or when comparing the HbsAg-positive HCC subgroup to controls. However, in HbsAg-negative subjects, the 72P allele was significantly associated with the presence of HCC (P=0.01) and had a higher risk (OR=1.69, 95% CI: 1.25-2.27) of HCC as compared to the 72R allele. By comparison to R/R homozygotes, the R/P heterozygotes and P/P homozygotes had a 1.73-fold (95% CI: 0.96-3.11) and a 3.29-fold (95% CI: 1.58-6.86) increased risk for HCC, respectively. The subjects with the 72P allele and a family history of HCC and those with the 72P allele and male gender also yielded an 11.14-fold (95% CI: 1.62-76.67) and a 9.39 fold (95% CI: 3.08-28.62) increased risk of HCC, respectively., Conclusion: The P allele of the p53 R72P polymorphism has an increased risk for HCC in HbsAg-negative subjects, and exerts a synergistic influence on the risk for HCC when combined with HCC family history and the male gender.

Objective: To investigate the possible association between the p53 Arg72Pro polymorphism and susceptibility to hepatocellular carcinoma (HCC) in Chinese population., Methods: Genomic DNA of the normal liver tissues was extracted from 507 patients with HCC confirmed by histopathological examination and 541 patients with benign liver diseases. PCR-based restriction fragment length polymorphism (RFLP) method was used to determine the p53 Arg72Pro genotypes. Odds ratios (ORs) for HCC and 95% confidence intervals (CIs) from unconditional logistic regression models were used to evaluate the relative risks. Potential HCC risk factors were included in the logistic regression models as covariates in the multivariate analyses on genotype and HCC risk., Results: The frequencies for Pro and Arg alleles were 0.445 and 0.555 respectively in the HCC cases, and 0.403 and 0.597 respectively in the controls. The Pro allele was marginally significantly associated with the presence of HCC (P = 0.053) and had an increased risk for HCC (OR = 1.19, 95% CI = 1.00 - 1.41) as compared to the Arg allele. Carriers of the Pro, or the "risk" allele, had a 1.33-fold increased risk (95% CI = 0.92 - 1.92, P = 0.133) of HCC compared to the Arg-only carriers. Compared to Arg/Arg homozygote, Arg/Pro heterozygote had a 1.21-fold increased risk (95% CI = 0.82 - 1.78, P = 0.341), whereas Pro/Pro homozygote had a 1.79-fold increased risk (95% CI = 1.06 - 3.01, P = 0.029) of HCC (Armitage's trend test, P = 0.046)., Conclusion: The Pro allele of p53 Arg72Pro is associated with the presence of HCC and Pro/Pro homozygote is potentially one of the risk genetic risk factors for HCC in Chinese population.

Objective: To assess the clinical features and prognostic factors of malignant ovarian teratoma., Methods: Eighty-four patients with malignant ovarian teratoma between 1954 and 2001 were studied retrospectively. All patients were treated with surgery, the mid-period of follow-up was 146 months. Patient characteristics, surgical therapy, pathologic diagnosis, histological grade, and follow-up data were extracted and survival curves were depicted. Statistical analysis was performed using SPSS software version 10.0., Results: The average age was (33.5 +/- 16.1) years. Abdominal pain and abdominal extension were the main complaint. Thirty-seven women were diagnosed with malignant transformation of ovarian teratoma while 47 were of ovarian immature teratoma. Clinical stage was the only prognostic factor with significantly statistical differentiation. Five-year survival rate of malignant ovarian teratoma with stage I, II, III, and IV were (87.20 +/- 4.52)%, (50.00 +/- 35.36)%, (30.55 +/- 9.43)%, and 0.00%, respectively (P = 0.00). Five-year survival rate of ovarian immature teratoma with histological grade I, II, and III were (90.48 +/- 6.41)%, (68.75 +/- 11.59)%, and (57.14 +/- 16.38)%, respectively (P = 0.08). Among 31 women died of malignant ovarian teratoma, 27 (87.1%) died within 2 years after operation., Conclusion: This retrospective study suggests that malignant transformation of ovarian teratoma is clinically different from ovarian immature teratoma. Complete staging surgery or Debulking surgery followed by 4-6 courses adjuvant chemotherapy with cisplatin, vincristine, and bleomycin are the principle treatment. Conservative surgery may well improve the life quality of younger patients. All patients should be closely followed up for at least 2 years.

Objective: To establish a novel approach for quick and high throughput verification of human gene imprinting., Methods: By use of a pair of dye-labeled probes, 5' nuclease assay was combined with reverse transcriptase-PCR(RT-PCR) to genotype a coding single nucleotide polymorphism (cSNP), rs705(C/T) of a known imprinted gene, small nuclear ribonucleotide protein N (SNRPN), on both genomic DNA and cDNA of human lymphoblast cell lines., Results: Allele discrimination showed a clear monoallelic expression pattern of SNRPN, which was confirmed by RT-PCR based restriction fragment length polymorphisms. Pedigree analysis verified the paternal origin of expressed allele, which is in consistency with previous report., Conclusion: Coding SNP is an ideal marker for detecting gene imprinting by 5' nuclease assay. This approach has also a potentiality to discover differential allele expression of non-imprinted genes in order to find gene cis-acting functional polymorphism.