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Through the thermodynamic calculation and analysis of nitrogen solubility in 1Mn18Cr18N protective ring steel， it is found that increasing the content of Cr and Mn elements in the steel can significantly improve the solubility of nitrogen. At the same time， the solubility of nitrogen increases as the molten steel temperature decreases . This paper describes the production process of 1Mn18Cr18N protective ring steel by non-vacuum induction furnace， electric furnace，AOD and LF refining， and alloying treatment with bottom blowing nitrogen， which is shorten the production time， and the composition control is quite stable. When AOD refining bottom blowing nitrogen is used for alloying， the nitrogen content in the molten steel can reach 0. 547% and the nitrogen solubility tends to be saturated. In the LF refining process， when using bottom blowing nitrogen and nitrogen-containing alloys， the nitrogen content in the steel can reach 0.68%.

Glow discharge ionization source can be used to analyze solid sample, liquid sample and gas sample. At present, glow discharge optical emission spectrometer (GD-OES) and glow discharge mass spectrometer (GD-MS) are mainly used to the elemental analysis of inorganic solid samples and quantitative depth profile analysis, including direct current (DC) power supply and radio frequency (RF) power supply. In this paper, the ionization of liquid sample and gas sample by low frequency radio frequency glow discharge (Lf-RFGD) was researched, and the glow discharge structure constructed was connected to timeof flight mass spectrometer(TOF MS). The influences of the vacuum degree of ionization chamber, the size of sample inlet capillary, the auxiliary gas pressure, the discharge radio frequency and the voltage difference between electrode plates on the ionization efficiency were studied. The optimal analysis conditions are the vacuum degree of ionization chamber is about 30 Pa, the length of sample inlet capillary is 150 mm and the inner diameter is 0.25 mm, the auxiliary gas pressure is about1.0 MPa, the low discharge frequency is 2 MHz, the voltage difference between electrode plates is about 100 V. Under these conditions, the discharge power is about 20 W,the detection limit of liquid sample is 0.1 pg and volatile sample is 20 mg/m3, and the detection resolution (full width at half maximum, FWHM) is about 3 000. Combined with samples testing, the Lf-RFGD TOF MS was preliminarily applied to the drug solution and volatile organic compounds (VOCs). However, the sensitivity of this instrument for detecting non volatile liquid sample was not good compared with the conventional detection instrument. The reason is that high proton affinity and low ionization potential are needed to obtain good detection sensitivity in the positive ion mode of mass spectrometer, and non volatile liquid sample without pretreatment is not easy to meet the condition of high proton affinity under low power glow discharge condition. Successfully, a lowcost, portable approach based on the application of atmospheric sampling Lf-RFGD TOF MS has been developed for near real time measurement of trace VOCs. In this context, the glow discharge excitation source offers attractive alternative for development of low cost VOCs and elemental analysis instrument. Lf-RFGD as an excitation source has unique advantages with respect to development of hand held instrument such as low cost, low power consumption, and analytical versatility.

Objective: To observe the effect of follicular fluid IL-6, TNF-α on the clinical outcome of in vitro fertilization and embryo transfer (IVF-ET) in patients with ovarian endometriosis., Method: From June 2013 to June 2014, the data of 64 (from Tangshan Maternal and Child Health Hospital IVF center) ovarian endometriosis patients was analyzed retrospectively. 58 infertility cases caused by male side were used as control group. Oocyte retrieval rate, M II oocytes rate, fertilization rate, recovery-intracytoplasmic sperm injection (R-ICSI) rate, good quality embryo rate, biochemical pregnancy rate and clinical pregnancy rate were analyzed and compared between two groups. Changes in the expression of follicular fluid IL-6, TNF-α were detected., Results: Oocyte retrieval rate, M II oocytes rate, fertilization rate, good quality embryo rate, biochemical pregnancy rate and clinical pregnancy rate in ovarian endometriosis group were significantly lower than those in the control group (all P < 0.05), while R-ICSI rate increased in ovarian endometriosis group compared with control group (P < 0.05). IL-6, TNF-α expressions of follicular fluid were higher in affected side of ovarian endometriosis patients than those in the unaffected side and those in control group., Conclusion: Inflammation microenvironment of the follicular fluid may influence IVF-ET outcomes in ovarian endometriosis patients.

Objective: To investigate the etiology, related factors and endoscopic characteristics of acute gastrointestinal hemorrhage., Methods: The data including age, gender, medical and medication history, and endoscopic characteristics of patients receiving emergency treatment for acute gastrointestinal hemorrhage between February 2006 and February 2010 were collected to analyze the etiological profiles of this disorder., Results: (1) A total of 1415 patients with a 2: 1 male-to-female ratio visited our hospital for acute gastrointestinal hemorrhage in the past 4 years. There was a higher mean age of disease onset in men than in women [(51 +/- 20) years old vs (61 +/- 17) years old, P = 0.000]. The numbers of patients were 399, 361, 242 and 413 for 4 respective quarters in order of sequence. (2) And 1030 patients received endoscopy. Among them, there were 897 (87.1%) with upper gastrointestinal hemorrhage and 133 (12.9%) with lower gastrointestinal hemorrhage. Significant differences existed in the mean age of two groups [(51 +/- 20) years old vs (57 +/- 18) years old, P = 0.000]. The male-to-female ratio was 656: 241 and 65:68 for these 2 groups respectively (P = 0.000). The percentage of patient with a history of NSAID (non-steroidal anti-inflammatory drug) treatment was 22.1% (n = 198) and 12.0% (n = 16) for these 2 groups respectively (P < 0.01). (3) The most common causative diseases of upper gastrointestinal hemorrhage were peptic ulcer (n = 546, 60.8%), esophageal & gastric varices hemorrhage (n = 130, 14.5%) and gastric cancer (n = 40, 4.6%). When the patients were divided into 5 groups of < 12 h, 12-24 h, 24-48 h, 48-72 h and > or = 72 h per time window of gastroscopy, their percentages with endoscopically active hemorrhage were 24.1% (20/83), 14.9% (24/161), 9.6% (16/166), 7.5% (8/106) and 7.6% (29/381) for these groups respectively with statistically significant differences. When peptic ulcer was examined by the Forrest classification, the ratio of grade I a- II c decreased gradually while the ratio of grade III increased gradually among 5 groups (chi2 = 80.414, P = 0.040). (4) The most common causative diseases of lower gastrointestinal hemorrhage were ischemic colitis (n = 44, 33.1%), small intestinal hemorrhage (n = 26, 19.5%) and colonic polyps (n = 18, 13.5%). (5) When the patients were divided into > 65 years old group (n = 277) and < or = 65 years old group (n = 620), the ratio of gastric ulcer and cancer in upper gastrointestinal hemorrhage was higher in the former than in the latter [23.5% (n = 65) vs 8.9% (n = 55) & 9.7% (n = 27) vs 2.1% (n = 13), P < 0.01)]. While the ratio of duodenal ulcer was lower in the former than in the latter [22.4% (n = 62) vs 49.7% (n = 308), P < 0.01]. The ratio of small intestinal hemorrhage in lower gastrointestinal hemorrhage was higher in the former than in the latter (all P < 0.01)., Conclusion: At the lowest in the third quarter, the incidence rate of acute gastrointestinal hemorrhage is higher in males than that in females at a lower age of onset. More common than lower gastrointestinal hemorrhage, upper gastrointestinal hemorrhage has a lower mean age of onset. Peptic ulcer is the most common disorder in upper gastrointestinal hemorrhage. Ischemic colitis is the most common disorder in lower gastrointestinal hemorrhage. The rate of gastric ulcer and gastric cancer in the old age group is higher than that in the young group. Emergency gastroscopy is recommended.

Objective: To investigate whether the gene transfer of phospholamban antisense RNA could inhibit remodeling and preserve cardiac function after myocardial infarction., Methods: Wistar rats received a ligation of left coronary with a direct intramyocardial injection of phospholamban antisense RNA eukaryote vector PcDNA4-asPLB. The cardiac function, hemodynamics and ventricular geometry of three groups (shame, saline injection and PcDNA4-asPLB injection) were studied by echocardiography and left ventricle hemodynamic recording. The levels of phospholamban (PLB) and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2a) were analyzed by Western blot and the expressions of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) examined by RT-PCR. The histological study was performed to evaluate the collage content and cardiomyocyte fiber size., Results: The PcDNA4-asPLB injection group had significantly better systolic cardiac function and diastolic function [LVEF (39.4 +/- 7.8)% vs (30.9 +/- 7.4)%, P < 0.05; dp/dt Max (1545 +/- 127) mm Hg x s(-1) vs (1172 +/- 91) mm Hg x s(-1), P < 0.05)]. Compared with saline injection, the PLB expression was inhibited by 50% in PcDNA4-asPLB injection group (PLB/beta-actin ratio, 0.28 +/- 0.07 vs 0.57 +/- 0.11, P < 0.05) and the function of SERCA2a was enhanced [(1.47 +/- 0.21) micromol x min(-1) x g(-1) protein vs (0.34 +/- 0.13) micromol x min(-1) x g(-1) protein, P < 0.05]. The expressions of ANP and BNP in the saline injection group were elevated as compared to those in the PcDNA4-asPLB injection group. Histological study also showed that the collage density and the cardiomyocyte fiber size in the saline injection group were worse than those in the PcDNA4-asPLB injection group., Conclusion: Intramyocardial injection of phospholamban antisense RNA eukaryote vector PcDNA4-asPLB after myocardial infarction results in PLB expression inhibition, attenuates ventricular remodeling and improves systolic and diastolic cardiac functions.

Objective: To investigate the differences on the diabetic foot problems and its risk factors in south and north of China., Methods: Patients with foot problems were surveyed from January 1 to December 31, 2004 in 14 teaching hospitals located in different cities in China, including demographic data, present and past history of the foot problems and peripheral artery disease (PAD), the classification of the foot ulcers based on the Wagner' system, control of the hyperglycemia and lipids disorder, medical cost in hospital and the diabetic complications. All the patients were divided into two groups due to their geographical data, south and north., Results: There were 285 and 349 patients for the group south and group north. No significant differences were found for duration of diabetes or foot problems, fasting or post-meal glucose, total cholesterol, triglycerides, HDL-C, and the numbers of patients with smoke, hypertension, nephropathy or neuropathy between the two groups. There were significant differences for the age (70 yrs vs 66 yrs), percentage of the patients with average person income with over RMB 1000 per month (57.7% vs 45.6%), coronary heart disease (42.6% vs 61.0%) and retinopathy (35.7% vs 49.5%), HbA1c (7.90% vs 8.80 %), LDL-C (2.75 mmol/L vs 2.98 mmol/L), WBC (6.70 x 10(9) vs 7.40 x 10(9)/L), HCT (0.37 vs 0.38), creatinine (87 micromol/L vs 76 micromol/L) and uric acid (333 mmol/L vs 271 mmol/L), and amputation rate (2.6% vs 9.7%) between south and north groups. Logistic analysis showed that severity of the foot problems was associated with ABI and WBC in south group, and with ABI, PLT and HCT in north group., Conclusion: Diabetic foot problems were more severe, with more risk factors and with more medical cost in north patients.

Objective: To investigate the characteristics of diabetic foot with neuropathy and its related factors., Methods: 530 out- and in-patients in 14 grade A class 3 comprehensive hospitals in China with foot problems were surveyed. 337 of the 500 patients (63.58%) suffered from neuropathy, 172 (32.45%) with diabetic foot with simple neuropathy and 165 (31.13%) with simple neuropathy combined with peripheral artery disease (PAD). 193 of the 500 patients (36.42%) suffered from peripheral artery disease (PAD). 77.7% of ulcer were caused by physical factors. Questionnaire survey was conducted to collect the demographic data, present and past history, history of the hyperglycemia and lipid disorders, classification and phases of the foot ulcers based on Wagner' system and Texas system, characteristics of neuropathy and other diabetic complications, and relative risk factors. Detailed physical examination was performed, including 10 g nylon filament sensation examination., Results: The duration of diabetic foot of the patients with simple neuropathy was 3 (1, 60) months, significantly shorter than that of the diabetic foot patients with PAD [5 (1, 96) months, P < 0.001]. The Wagner degree of ulcer was related to the duration of diabetes, economic income, foot deformity, nerve reflection, diapason vibration sensation of foot, sensation point of 10 g nylon filament, ankle/brachial index (ABI), foot artery pulse, fasting blood sugar (FBS) and glycated hemoglobin (HbA1c). Stepwise regression analysis revealed that ABI of left posterior tibial artery, vibration detection threshold and economic income were the most significant influencing factors of the degree of ulcer., Conclusion: Neuropathy ulcer is common in diabetic foot patients. The prognosis of healing in diabetic foot with neuropathy is prior to that of diabetic foot with PAD. The neuropathy and PAD of foot influence each other and aggravate the condition of diabetic foot. The examinations of diapason vibration sensation of foot, sensation point of 10 g nylon filament, and Achilles tendon reflex are simple and practical, and are worth recommending.