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Objective@#To analyze the total fluids intake and sources of college students from Hebei in spring and summer, and to provide a scientific reference for appropriate fluids intake in different seasons.@*Methods@#Subjects were recruited in a university in Baoding, Hebei Province, and investigations were conducted in April and June 2021. The number of people who completed both spring and summer investigations was 80. Quantitative instruments and 7 day 24 h Fluid Intake Questionnaire were used to investigate the total drinking fluids, and it was recorded for 7 consecutive days in spring and summer respectively. The duplicate portion method was used to investigate the water from food. The total fluids intake and sources among subjects were analyzed in spring and summer.@*Results@#There was no statistical significance between the total drinking fluids and total fluids intake between spring and summer [1 141(715), 1 176(649)mL/d, (2 496±604)(2 458±554)mL/d] ( F=1.86, 0.59, P >0.05). Spring showed significantly higher water from food compared with summer [(1 318±274)(1 217±302)mL/d]( F=16.63, P <0.05). The proportions of total drinking fluids and water from food in spring were 46% and 54%, respectively, and both were 50% in summer, the differences were statistically significant ( F=12.97, 12.97, P <0.05). There were differences in total fluids intake,total drinking fluids and water from food of different genders in earch season ( t/Z =4.75, -3.63, 3.44; 4.80, -2.91, 4.01, P <0.05). There were differences in total water intake, total drinking fluids, the proportions of total drinking fluids and water from food of different BMI groups in each season ( F/H =8.08, 16.65, 3.03, 3.03; 7.11,17.97, 4.52, 4.52, P <0.05). In spring, only 13.8% of subjects achieved the recommended total drinking fluids of China, compared with 18.8% in summer. In spring and summer, the total fluids intake, total drinking fluids, the proportions of total drinking fluids in the group achieved the recommendation were all higher than those who did not reach the recommendation ( t/Z =6.64, -5.19, 5.79; 8.12, -5.97, 5.70, P <0.05).@*Conclusion@#Season is a factor that affects total fluids intake, and it should be taken into account when setting the recommendation on adequate water intake.
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Objective@#To understand the knowledge, attitudes and practices of drinking water among college students of Hebei Province, to provide evidence for health education.@*Methods@#A total of 715 subjects were selected from a university in Baoding City, Hebei Province in March 2017 by random cluster sampling. Knowledge, attitude and behavior of drinking water among college students were investigated by self-designed questionnaires.@*Results@#The awareness rate of water consumption of 1 500-1 700 mL was 19.0%, the awareness rate of drinking modes was 95.0%, the awareness rate of suitable drinking time was 30.1%, the awareness rate on drinking water was higher among girls and medical major sutdents (χ2=22.16, 12.49, P<0.05); the awareness rate on the relationship between insufficient drinking water and stroke, hypertension and coronary heart disease was generally low, with sophornore higher than freshman (χ2=11.10, P<0.05). The most common medium for accessing drinking water knowledge among the respondents was network (60.0%), followed by campus publicity/classroom teaching (48.3%). 99.6% of the respondents believed that drinking water was important to health, 98.3% were willing to change their drinking habits, 93.0% were willing to pay attention to drinking water education, and the proportion of female students was higher than that of male students (χ2=5.46, 6.49, 8.01, P<0.05). In real life, 48.4% of the respondents drank water on an empty stomach in the morning and 40.7% before going to bed. 45.5% of the respondents drank water when they thought of it.@*Conclusion@#College students in Hebei province are generally lack of appropriate awareness on water drinking, which varied in sex, grade and major. While the attitude towards water drinking is satisfactory, drinking behavior need to be improved.
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At present, methods of water-intake survey include government, industry, sector statistics data, dietary survey (24 hours dietary recall, dietary record and food frequency questionnaire), fluid intake survey (retrospective fluid-intake questionnaire, 1-5 days 24 hours fluid-intake survey, 7 days 24 hours fluid-intake record), weighing method with the food composition table, weighing method, duplicate portion method and chemical analysis, and so on. The method of 7 days 24 hours fluid-intake record is an internationally recognized and authoritative method for fluid-intake survey with the highest accuracy, which can reflect the differences of fluid intake between working and non-working days, and can obtain detailed data on behaviors and patterns of fluid water, such as the time, types and places of fluid intake. The method of combining weighing method, duplicate portion method and chemical analysis is used to analyze water intake from food with the highest accuracy, which can be used in an extensive range of population and areas, but with high cost and complex operating steps. It is of great practical significance to compare and evaluate the advantages and disadvantages of different methods about water-intake survey, which will be helpful for researchers to choose appropriate methods for water-intake survey to obtain accurate and representative data in various areas, different population, and complex circumstances.
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Objectives@#To investigate the total fluids intake, volume of urine and hydration status among college students from Hebei Province in spring.@*Methods@#In March 2017, the subjects were recruited in a college in Baoding, Hebei Province. 156 students completed the investigation. Total drinking fluids was assessed by 7-day 24-hour fluid intake questionnaire, with a quantitative tool. The water from food was assessed by the duplicate portion method. The urine samples of 24-hour was collected for 3 consecutive days, and the volume, osmolality, pH and specific gravity of urine were measured. Hydration status was grouped to three types according to the urine osmolality (mOsm/kg), namely, optimal hydration (urine osmolality ≤500), middle hydration (500< urine osmolality ≥800) and dehydration (urine osmolality >800), and the differences among subjects in different genders and hydration statuses were compared.@*Results@#The age of all subjects was (19.8±1.1) years old, including 80 male students. The median amounts of total fluids intake, total drinking fluids, water from food and urine volume were 2 324, 1 135, 1 174 and 1 279 ml/d, respectively. The volume of urine among males was 1 272 ml/d, which was not significantly different from that of females (1 304 ml/d) (P>0.05). The osmolality and specific gravity of urine among males were 688 mOsm/kg and 1.017, which were higher than those of females (493 mOsm/kg, 1.014) (P<0.05). But the pH of males was 6.6±0.3, which was lower than that of females (6.7±0.3) (P<0.05). Only 37.2% (n=58) of college students were in optimal hydration status. The median of the amount of total drinking fluids among subjects in optimal hydration status was 301, 448 ml/d higher than that in middle hydration status and dehydration, respectively (P<0.05). The proportion of females in optimal hydration status was 51.3% (n=39), which was higher than that of males 23.8% (n=19) (P<0.05).@*Conclusion@#Large proportion of college students in Hebei had lower total drinking fluids than the recommended intake of China, and the volume of urine was equal to the amount of total drinking fluids among the college students. Only 37.2% of college students were in optimal hydration status, and the proportion of female college students in optimal hydration status was larger than that of males.
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Objective@#To investigate the food source of water of college students from Hebei Province in spring.@*Methods@#In March 2017, the subjects were recruited in a college in Baoding, Hebei Province. 156 students completed the investigation. All foods were collected for 3 consecutive days using duplicate portion study combined with weighing method to test the water content of various foods. To analyze the water content of the food and calculate the proportion to the total amount of food water intake, the edible parts of each meal were divided into staple food, dishes, porridge, soup and snacks. Body mass index (BMI) was grouped according to quartiles, and the differences in food intake and food water sources among subjects of different genders and BMI were compared.@*Results@#The age of subjects was (19.8±1.1) years old, including 80 male students. The median intake of staple food, dishes, porridge, soup and snacks per day was 562 g, 743 g, 111 g, 102 g and 0 g, respectively. The median intake of water from staple food, dishes, porridge, soup and snacks per day was 301 ml/d, 620 ml/d, 97 ml/d, 93 ml/d and 0 ml/d, respectively. The median ratio of water intake to total food water intake of staple food, dishes, porridge, soup and snacks was 27%, 53%, 8%, 8% and 0%, respectively. The median intake of water from staple food and dishes in male students was significantly higher than that of female students (P<0.05). The amount of water intake from porridge of female students was significantly higher than that of male students (P<0.05). There was no significant difference in the water intake from soup and snacks between different genders. There was no significant difference in food intake and food water sources among college students with different BMI (P>0.05).@*Conclusion@#The food source of water of college students from Hebei Province in spring is mainly based on dishes and staple foods. The food source of water for boys and girls is different.
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Objectives@#To investigate the total fluids intake among college students in spring from Hebei.@*Methods@#In March 2017, the subjects were recruited in a college in Baoding, Hebei Province. 156 students completed the investigation. Total drinking fluids was assessed by 7-day 24-hour fluid intake questionnaire, with a quantitative tool. The water from food was assessed by duplicate portion method. The sources of total fluids intake among subjects were analysed.@*Results@#The age of subjects was (19.8±1.1) years old, including 80 male students. The median amounts of total fluids intake, total drinking fluids and water from food were 2 324, 1 135 and 1 174 ml, respectively. The proportions of total drinking fluids and water from food in total fluids intake were 51%±9% and 49%±10%. Only 19.9% (n=31) and 18.6% (n=29) of college students had adequate total fluids intake and total drinking fluids, according to the recommendation of China. The median amounts of total fluids intake, total drinking fluids and water from food were 3 210, 1 860 and 1 093 ml/d, respectively. The proportion of total drinking fluids in total fluids intake was 61%±7%, which were all higher than those who did not reach the recommended intake (2 158, 1 000, 1 149 ml/d; drinking fluids accounting for 46%±8% of total fluids intake) (P<0.05).@*Conclusion@#The amounts of total fluids intake and total drinking fluids of college students in Hebei Province are lower than the recommended intake in China. The contributions of total drinking fluids and water from food to total fluids intake were nearly same.
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Objective@#To investigate the total amount and types of fluid intake among college students in Hebei Province during spring and to provide scientific basis for fluid-intake education.@*Methods@#A simple random sampling method was used to select 156 college students from a college in Hebei Province. The information on amount and type of fluid intake was recorded using the 7-day 24-hour recording method. A separate analysis was performed on people who consumed beverages during the 7 days.@*Results@#The median intake of plain water, milk, sugar-sweetened beverages and other beverages was 866 mL, 43 mL, 43 mL and 2 mL, respectively. The median of plain water, milk, sugar-sweetened beverages and other beverages by the beverage-consumers was 845 mL, 36 mL, 63 mL and 11 mL, respectively. The intake of plain water and sugar-sweetened beverages in male students was significantly higher(Z=2.31, 3.03; 2.31, 2.11, P<0.05), and milk consumption was lower than female students of these two groups of people(Z=-2.73, -2.23, P<0.05). The intake of other beverages in male students was higher than that of female students, but only significant among beverage-consumers(Z=3.31, P<0.01). There was no significant difference in the total amount of different fluid types among different BMI(P>0.05).@*Conclusion@#College students in Hebei Province mainly drink plain water. Sex difference is observed in the types of fluid intake.
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Objective@#To investigate the association of within-day drinking occasions with average amount consumed per drinking occasion during spring among college students in Hebei Province and to provide the basic data for the revision of quantity of consumption among Chinese residents.@*Methods@#A total of 156 college students in Hebei Province were selected by using simple random sampling method. Information on daily amount and types of water consumption was recorded using the 7-day 24-hour recording method. The daily amount and type of drinking water by sex and BMI were analyzed and compared.@*Results@#The daily median drinking water intake was 1 135 mL; the daily median number of drinking occasion was 6, with 34.6% of participants less than 6 drinking occasions; the median amount consumed per drinking occasion was 177 mL. The daily number of water and plain water drinking occasion of females were higher than males(χ2/Z=8.34, -2.03, P<0.05); the amount consumed per drinking occasion, the amount of plain water and beverages consumed per drinking occasion of males were higher than females(χ2/Z=23.86, -5.48, 3.70, P<0.01); The differences of the amount of plain water consumed per day among students and their BMI were of statistical significance(χ2=9.17, P=0.03), the amount of drinking water each time was positively correlated with body surface area(r=0.18, P=0.03), and frequency of drinking water was positively correlated with the amount of drinking water, negatively correlated with the amount of drinking water each time. The amount of drinking water was positively correlated with the amount of drinking water each time(r=0.30, -0.47, 0.61, P<0.01).@*Conclusion@#There is a certain proportion of unhealthy drinking behavior among college students; drinking behavior is different by sex and BMI. With the increase of drinking occasions, the amount consumed in each drinking occasion decreases, but total amount of drinking water increases.
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Objective@#To retrospectively explore the effects of modified dosage of calcium gluconate (CG) on the patients with hydrofluoric acid burns not in hands or feet.@*Methods@#One hundred and sixty patients with hydrofluoric acid burns not in hands or feet were hospitalized in our burn ward from January 2004 to December 2017. Based on the dosage of CG at different admission time, 76 patients hospitalized from January 2004 to December 2012 were included in traditional group, and 84 patients hospitalized from January 2013 to December 2017 were included in modified group. For patients in the two groups, subcutaneous injection of CG solution at one time was immediately conducted on admission in topical treatment. In traditional group, the injection was CG solution with mass concentration of 100 g/L. For wounds of superficial partial-thickness and above degree, CG solution was prescribed at the dosage of 50 mg/cm2. Wounds of superficial-thickness or mass fraction of hydrofluoric acid less than 20.0% did not receive injection. In modified group, the mass concentration of CG solution for injection was diluted with normal saline to 25 g/L. For wounds of deep partial-thickness and above degree, CG solution was prescribed at the dosage of (50×mass fraction of hydrofluoric acid) mg/cm2. For wounds of superficial partial-thickness, CG solution was prescribed at the dosage of (25×mass fraction of hydrofluoric acid) mg/cm2. For wounds of superficial-thickness, CG solution was prescribed at the dosage of 2.5 mg/cm2. For systemic treatment, the injection velocity of CG solution via venous access was adjusted according to the level of serum calcium namely total serum calcium of patients in traditional group. In modified group, serum ionized calcium was additionally detected through automatic blood gas analyzer by the bed to regulate the injection velocity of CG via venous access. The incidence rate of hypercalcemia and mortality of patients after treatment in the two groups, and the situation about treatment of survivors in the two groups were analyzed. Data were processed with chi-square test, Fisher′s exact probability test, t test, and Mann-Whitney U test.@*Results@#(1) After treatment, 9 patients (11.8%) had hypercalcemia, while the other 67 patients (88.2%) did not have hypercalcemia in traditional group. Two patients (2.4%) had hypercalcemia, while the other 82 patients (97.6%) did not have hypercalcemia in modified group. The incidence rate of hypercalcemia of patients in traditional group was significantly higher than that in modified group (χ2=5.579, P=0.02). (2) There were two deaths (2.6%) and 74 survivors (97.4%) in traditional group, while there were two deaths (2.4%) and 82 survivors (97.6%) in modified group. The mortalities of patients in the two groups were close (P>0.05). (3) The ratios of eschar excision and skin grafting and hyperplastic scar formation, wound healing time, and ratio of esophageal scar stenosis of survivors in the two groups were close (χ2=0.002, 0.054, Z=0.66, P>0.05).@*Conclusions@#Hydrofluoric acid is highly dangerous. The early management of patients with hydrofluoric acid burns emphasizing specialized dosage of CG for treatment can be helpful to reduce incidence of complications and improve the safety of treatment.
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Objective@#To investigate the clinical characteristics of patients with hydrofluoric acid (HF) burns.@*Methods@#Clinical data of 316 patients with HF burns admitted to Zhejiang Quhua Hospital from January 2004 to December 2016 were retrospectively analyzed. Patients were divided into non and mild poisoning group (NMP, n=157), moderate poisoning group (MP, n=120), and severe and fatal poisoning group (SFP, n=39) based on the severity of poisoning. Occurrences of hypocalcemia, hypomagnesemia, hypokalemia, and hyperkalemia of patients within 24 hours after admission were recorded. Values of emergency urinary fluoride of patients on admission were recorded. Values of urinary fluoride of patients admitted to hospital in 4 hours post injury in groups MP and SFP at post injury hour 4, 12, and 24 and on post injury day 2, 3, 4, 5, 6, and 7 were also recorded. Electrocardiographic abnormalities of patients within 24 hours after admission were recorded. Data were processed with chi-square test, Kruskal-Wallis H test, and Mann-Whitney U test.@*Results@#(1) Hypocalcemia, hypomagnesemia, and hypokalemia occurred in some patients in each of the three groups, but no patient had hyperkalemia. Taking serum calcium namely total serum calcium as reference, the incidence rate of hypocalcemia of patients in group NMP was close to that in group MP (χ2=0.05, P>0.05). The incidence rate of hypocalcemia of patients in group SFP was significantly higher than that in group NMP or group MP (χ2=10.53, 7.92, P<0.01). The incidence rates of hypokalemia in the three groups were close (χ2=0.63, P>0.05). Taking serum ionized calcium as reference, the incidence ratio of hypocalcemia of patients in group NMP was close to that in group MP (χ2=0.01, P>0.05), while there were statistically significant differences in incidence ratio of hypocalcemia of patients between group SFP and each of group NMP and group MP (χ2=4.66, 4.47, P<0.05). Taking serum calcium as reference, the incidence rate of hypocalcemia of patients was 7.3% (23/316). Taking serum ionized calcium as reference, the incidence rate of hypocalcemia of patients was 60.0% (42/70), which was significantly higher than that of taking serum calcium as reference (χ2=113.74, P<0.01). The incidence rates of hypomagnesemia of patients in groups MP and NMP were close (χ2=0.02, P>0.05). The incidence rate of hypomagnesemia of patients in group SFP was significantly higher than that in group NMP or group MP (χ2=14.69, 9.94, P<0.01). (2) The urinary fluoride levels were tested in 288 patients, with the value of emergency urinary fluoride of patients on admission 0.2-590.0 mg/L. The values of urinary fluoride of 202 patients were above the normal value. The values of emergency urinary fluoride of patients in groups NMP, MP, and SFP were 2.15 (1.11, 4.30), 5.89 (1.72, 14.25), and 36.0 (13.2, 103.2) mg/L, respectively. The values of emergency urinary fluoride of patients in groups MP and SFP were significantly higher than the value in group NMP (χ2=23.28, 66.03, P<0.01). The value of emergency urinary fluoride of patients in group SFP was significantly higher than that in group MP (χ2=39.23, P<0.01). The value of urinary fluoride of 33 patients admitted to hospital within 4 hours post injury in groups MP and SFP reached the top at 4 hours post injury and then gradually declined, which returned to normal on about 5 days post injury. The values of urinary fluoride of patients in group SFP at 4, 12, and 24 hours post injury and on 2, 3, 4, 5, 6, and 7 days post injury were significantly higher than those in group MP (Z=-4.28, -4.15, -3.81, -4.21, -2.48, -2.06, -2.31, -2.68, -3.03, P<0.05 or P<0.01). (3) Twenty-seven patients had electrocardiographic abnormality. There were 12 patients with T wave changes (the most common), 8 patients with ST-T changes, 6 patients with ventricular arrhythmias, 6 patients with conduction block, and 1 patient with broadened QRS waveform. There was no patient with prolonged Q-T interval. The ratios of patients with the above electrocardiographic abnormalities in group SFP were higher than those in group NMP and group MP.@*Conclusions@#Clinical manifestations of patients with HF burn are hypocalcemia, hypomagnesemia, hypokalemia, and electrocardiographic abnormality. In addition to routine serum electrolyte and electrocardiogram monitoring, the levels of serum ionized calcium and urinary fluoride can be helpful to evaluate the severity of illness of the patients.
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Objective To study the clinical manifestation of preeclampsia complicated with placental abrup-tion and its treatment measures.Methods 160 patients with placenta abruption were selected,and the patients with preeclampsia complicated with placental abruption were selected as the study group(70 cases),and the patients with non preeclampsia complicated with placental abruption were selected as the control group(90 cases).The clinical manifestations,infant outcome and treatment measures of the two groups were compared.Results When the disease attack of the study group often accompanied with vaginal bleeding,but few had symptoms of abdominal pain,the main symptoms of the control group was vaginal bleeding and abdominal pain.The occurrence rate of abdominal pain of the two groups had statistically significant difference(4.3%vs 92.2%,χ2 =11.032,P0.05);The incidence of neonatal asphyxia of the two groups had no significant difference(56.6%vs 55.6%,P>0.05);The perinatal mortality of the two groups had sta-tistically significant difference(31.7%vs 11.1%,P0.05).Conclusion The clinical manifestation of preeclampsia was not typical,with a greater harm to the fetus and perinatal infant,operation to termination of pregnancy is the main method for treatment of preeclamp-sia complicated with placenta abruption.
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Objective To investigate the risk actors of postpartum hemorrhage of cesarean section,in order to provide the basis for the prevention of hemorrhage after cesarean section.Methods A case-control study was conducted in 100 cases with postpartum hemorrhage of cesarean section and 200 cases without bleeding of cesarean section.The clinical data were compared and analyzed.The single factor and multiple factors of the Logistic analysis was used to analyze the risk factors of postpartum hemorrhage of cesarean section.Results Fetal macrosomia (OR =3.678,95％ CI:1.456-5.345),placenta adhesion (OR =4.264,95％ CI:1.556-5.646),placenta praevia (OR =2.754,95％ CI:1.754-5.456),multifetal pregnancy (OR =3.964,95％ CI:1.274-4.453) were the risk factors of postpartum hemorrhage after cesarean section.Conclusion Evaluation of the above risk factors before cesarean section was important for prevention of postpartum hemorrhage.
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Lysins are murein hydrolases produced by bacteriophage that act on the cell wall of host bacteria to release progeny phages. Research indicated that lysins could kill bacteria effectively and specifically in vitro. To prepare recombinant bacteriophage lysin of Streptococcus (PlyC) and analyze its biological activity, we obtained two genes of PlyC named PlyCA and PlyCB by PCR amplification and inserted them into pET-32a(+), then transformed the recombinant expression vectors pET-32a(+)-PlyCA and pET-32a(+)-PlyCB into E. coli BL21(DE3) respectively. After induction with 0.7 mmol/L IPTG at 30 degrees C for 7 h, PlyCA and PlyCB were successfully expressed, SDS-PAGE analysis determined that they all constituted above 30% of the total cell proteins. After Ni(2+)-NTA affinity chromatography, the purity was more than 95%. With the denaturation and protein refolding, we gained the recombinant PlyC. To determine its biological activity, we adopted turbidimetry and plate count method. Before and after lysin treatment, the cell morphology was studied by scanning electron microscopy (SEM). The results showed that the recombinant PlyC could specifically cleavage Streptococcus pyogenes (group A beta-hemolytic streptococci). Under the incubation time of 60 min with 4 microg/mL PlyC in Streptococcus pyogenes dilution which OD600 was 0.56, the germicidal effect was up to 99.6%, while SEM observations showed that cell wall cracked and presented cell debris. This finding laid the foundation for the further study and achieving an effective treatment for streptococcal infection.
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Bacteriolysis , Enzymes , Genetics , Escherichia coli , Genetics , Metabolism , Recombinant Proteins , Genetics , Streptococcus pyogenesABSTRACT
BACKGROUND:Insulin-like growth factor-1(IGF-1)is an important cell factor which plays a special role in many disease treatments such as diabetes.The research of engineering bacteria fermentation production technology is great to IGF-1 industrialization and to clinical application.OBJECTIVE:To investigate the high cell-density fermentation and expression condition of recombinant human insulin-like growth factor-1(IGF-1) engineering bacteria.DESIGN,TIME AND SETTING:The enzyme,gene engineering,study was performed at the Biotechnological Laboratory of Zhejiang Shuren University from May 2007 to May 2008.MATERIALS:Recombinant E coli strain for IGF-1 expression as BL21 (DE3)/pET22a-IGF-1 was reserved in the Biotechnological Laboratory of Zhejiang Shuren University.Nutrient feed was composed of:glucose(300 g/L),peptone(40 g/L),yeast powder(10 g/L),Na2HPO4(280 mmol/L),Na2HPO4-2H2O2(120 mmol/L),MgSO4(10 mmol/L),and ampicillin(100 mg/L).METHODS:The strains were activated and then cultured in orbitaI shakers.Parameters such as types of media,isopropyl-β-D-thiogalactopyranoside(IPTG)concentration and induction time have been analyzed to explore optimaI fermentation conditions for expressing the recombinant protein.According to the optimal fermentation condition of orbitaI shakers.batch fermentation was carried on with 5 L-autocontroI fermentor.The process contained two stages:batch culture and fed-bafch through pH-stat solution.JPTG was added to jnduce the expression of protein in the middle and latter of the logarithmic growth phase for 4-βhours.MAIN OUTCOME MEASURES:Following described parameters were measured:fermentation and protein expression of the recombinant human IGF-1 engineering bacteria,cell concentration,cell dry weigh,objective protein,glucose concentration.RESULTS:Cells were cultured in 2×YT+5 g,L glucose medium,induced by 0.8 mmol/L IPTG for 5 hours.By controlling dissolved oxygen and by pH-stat feeding solution,high cell-density and high protein expression were achieved.Under the establishedconditions.50.1 g dry cell weight(DCW)/L could be obtained,and 5.25 g/L IGF-1 was achieved.CONCLUSION:The established high cell-density fermentative procedure of recombinant human IGF-1 engineering bacteda is the useful bases for further pudfication and large scale production of IGF-1.