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This study collected epidemic data of COVID-19 in Zhengzhou from January 1 to January 20 in 2022. The epidemiological characteristics of the local epidemic in Zhengzhou High-tech Zone caused by the SARS-CoV-2 Delta variant were analyzed through epidemiological survey and big data analysis, which could provide a scientific basis for the prevention and control of the Delta variant. In detail, a total of 276 close contacts and 599 secondary close contacts were found in this study. The attack rate of close contacts and secondary close contacts was 5.43% (15/276) and 0.17% (1/599), respectively. There were 10 confirmed cases associated with the chain of transmission. Among them, the attack rates in close contacts of the first, second, third, fourth and fifth generation cases were 20.00% (5/25), 17.86% (5/28), 0.72% (1/139) and 14.81% (4/27), 0 (0/57), respectively. The attack rates in close contacts after sharing rooms/beds, having meals, having neighbor contacts, sharing vehicles with the patients, having same space contacts, and having work contacts were 26.67%, 9.10%, 8.33%, 4.55%, 1.43%, and 0 respectively. Collectively, the local epidemic situation in Zhengzhou High-tech Zone has an obvious family cluster. Prevention and control work should focus on decreasing family clusters of cases and community transmission.
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Humans , SARS-CoV-2 , COVID-19 , Epidemics , IncidenceABSTRACT
Background@#A novel coronavirus (2019-nCoV) causing an outbreak of pneumonia in Wuhan, Hubei province of China was isolated in January 2020. This study aims to investigate its epidemiological history, and analyzed the clinical characteristics, treatment regimens and prognosis of patients infected with 2019-nCoV during this outbreak.@*Methods@#Clinical data from 137 2019-nCoV-infected patients admitted to the respiratory departments of nine tertiary hospitals in Hubei province from December 30, 2019 to January 24, 2020 were collected, including general status, clinical manifestations, laboratory test results, imaging characteristics, and treatment regimens.@*Results@#None of the 137 patients (61 males, 76 females, aged 20-83 years, mean age 55 ± 16 years) had a definite history of exposure to Huanan Seafood Wholesale Market. Major initial symptoms included fever (112/137, 81.8%), coughing (66/137, 48.2%), and muscle pain or fatigue (44/137, 32.1%), with other, less typical initial symptoms observed at low frequency, including heart palpitations, diarrhea, and headache. Nearly 80% of the patients had normal or decreased white blood cell counts, and 72.3% (99/137) had lymphocytopenia. Lung involvement was present in all cases, with most chest computed tomography scans showing lesions in multiple lung lobes, some of which were dense; ground-glass opacity co-existed with consolidation shadows or cord-like shadows. Given the lack of effective drugs, treatment focused on symptomatic and respiratory support. Immunoglobulin G was delivered to some critically ill patients according to their condition. Systemic corticosteroid treatment did not show significant benefits. Notably, early respiratory support facilitated disease recovery and improved prognosis. The risk of death was primarily associated with age, underlying chronic diseases, and median interval from the appearance of initial symptoms to dyspnea.@*Conclusions@#The majority of patients with 2019-nCoV coronavirus pneumonia present with fever as the first symptom, and most of them still showed typical manifestations of viral pneumonia on chest imaging. Middle-aged and elderly patients with underlying comorbidities are susceptible to respiratory failure and may have a poorer prognosis.
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BACKGROUND@#The 2019 novel coronavirus (2019-nCoV) causing an outbreak of pneumonia in Wuhan, Hubei province of China was isolated in January 2020. This study aims to investigate its epidemiologic history, and analyze the clinical characteristics, treatment regimens, and prognosis of patients infected with 2019-nCoV during this outbreak.@*METHODS@#Clinical data from 137 2019-nCoV-infected patients admitted to the respiratory departments of nine tertiary hospitals in Hubei province from December 30, 2019 to January 24, 2020 were retrospectively collected, including general status, clinical manifestations, laboratory test results, imaging characteristics, and treatment regimens.@*RESULTS@#None of the 137 patients (61 males, 76 females, aged 20-83 years, median age 57 years) had a definite history of exposure to Huanan Seafood Wholesale Market. Major initial symptoms included fever (112/137, 81.8%), coughing (66/137, 48.2%), and muscle pain or fatigue (44/137, 32.1%), with other, less typical initial symptoms observed at low frequency, including heart palpitations, diarrhea, and headache. Nearly 80% of the patients had normal or decreased white blood cell counts, and 72.3% (99/137) had lymphocytopenia. Lung involvement was present in all cases, with most chest computed tomography scans showing lesions in multiple lung lobes, some of which were dense; ground-glass opacity co-existed with consolidation shadows or cord-like shadows. Given the lack of effective drugs, treatment focused on symptomatic and respiratory support. Immunoglobulin G was delivered to some critically ill patients according to their conditions. Systemic corticosteroid treatment did not show significant benefits. Notably, early respiratory support facilitated disease recovery and improved prognosis. The risk of death was primarily associated with age, underlying chronic diseases, and median interval from the appearance of initial symptoms to dyspnea.@*CONCLUSIONS@#The majority of patients with 2019-nCoV pneumonia present with fever as the first symptom, and most of them still showed typical manifestations of viral pneumonia on chest imaging. Middle-aged and elderly patients with underlying comorbidities are susceptible to respiratory failure and may have a poorer prognosis.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Betacoronavirus , China , Coronavirus Infections , Diagnostic Imaging , Fever , Pandemics , Pneumonia, Viral , Diagnostic Imaging , Tertiary Care Centers , Tomography, X-Ray ComputedABSTRACT
Objective To predict the monthly incidence of hand-foot-mouth disease (HFMD) in China by using autoregressive integrated moving average (ARIMA) model and provide evidence for prevention and control of HFMD. Methods The monthly incidence data of HFMD in China from 2008 to 2016 were collected from the Public Health Science data Center. The incidence database was established by Excel 2007 and graphed. SAS 9.1 was used to construct the ARIMA model, based on the data of the monthly reported incidence of HFMD in China from January 2008 to December 2015, and then the data in 2016 were used to verify the predicted results. The monthly incidence in 2017 was predicted in the same way.The difference was statistically significant when P<0.05. Result The model predicting monthly incidence of HFMD in China is ARIMA ((12), 2, 0) sparse coefficient and residuals is white noise. The parameters were as follows: moted mean squared error=3.6490, mean absolute error=2.62, mean absolute percentage error=28.24%. Conclusion The sparse coefficient model could well simulate the trend of HFMD case in time series, which has good reference of early warning and prevention of HFMD.
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OBJECTIVE@#To explore the clinical efficacy of VSD vacuum suction combined with anterolateral thigh perforator flap in repairing diabetic foot ulcer.@*METHODS@#From June 2015 to December 2017, 12 patients with diabetic foot, including 8 males and 4 females, with an average age of 57.4 years old (ranged 49 to 71 years old) and ulcer formation time (1 month to 2 years) were analyzed retrospectively. The wound area of ulcer ranged from 3 cm×5 cm to 7cm×10 cm. All the patients were treated with debridement and VSD negative pressure aspiration, washing with Chinese medicine lotion and flap repair. The survival, appearance and sensory recovery of the flap were observed.@*RESULTS@#All 12 flaps survived after operation, and the wounds were successfully repaired. The donor site healed well. During the follow-up of 6 to 18 months, the flaps of 12 patients survived well and their appearance was satisfactory, sensory partial recovery.@*CONCLUSIONS@#The clinical effect of VSD negative pressure drainage combined with anterolateral femoral perforator flap after debridement of diabetic foot ulcer is satisfactory and worth popularizing.
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Diabetic Foot , Perforator Flap , Plastic Surgery Procedures , Retrospective Studies , Skin Transplantation , Soft Tissue InjuriesABSTRACT
Atorvastatin is proven to ameliorate cardiac hypertrophy induced by chronic intermittent hypoxia (CIH).However,little is known about the mechanism by which atorvastatin modulates CIH-induced cardiac hypertrophy,and whether specific hypertrophyrelated microRNAs are involved in the modulation.MiR-31 plays key roles in the development of cardiac hypertrophy induced by ischemia/hypoxia.This study examined whether miR-31 was involved in the protective role of atorvastatin against CIH-induced myocardial hypertrophy.H9c2 cells were subjected to 8-h intermittent hypoxia per day in the presence or absence of atorvastatin for 5 days.The size of cardiomyocytes,and the expression of caspase 3 and miR-31 were determined by Western blotting and RT-PCR,respectively.MiR-31 mimic or Ro 31-8220,a specific inhibitor of protein kinase C epsilon (PKCε),was used to determine the role of miR-31 in the anti-hypertrophic effect of atorvastatin on cardiomyocytes.PKCε in the cardiomyocytes with miR-31 upregulation or downregulation was detected using RT-PCR and Western blotting.The results showed that CIH induced obvious enlargement of cardiomyocytes,which was paralleled with increased atrial natriuretic peptide (ANP),brain natriuretic peptide (BNP),and slow/beta cardiac myosin heavy-chain (MYH7) mRNA levels.All these changes were reversed by the treatment with atorvastatin.Meanwhile,miR-31 was increased by CIH in vitro.Of note,the atorvastatin pretreatment significantly increased the mRNA and protein expression of PKCε and decreased that of miR-31.Moreover,overexpression of miR-31 abolished the anti-hypertrophic effect of atorvastatin on cardiomyocytes.Upregulation and downregulation of miR-31 respectively decreased and increased the mRNA and protein expression of PKCε.These results suggest that atorvastatin provides the cardioprotective effects against CIH probably via up-regulating PKCε and down-regulating miR-31.
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Atorvastatin is proven to ameliorate cardiac hypertrophy induced by chronic intermittent hypoxia (CIH).However,little is known about the mechanism by which atorvastatin modulates CIH-induced cardiac hypertrophy,and whether specific hypertrophyrelated microRNAs are involved in the modulation.MiR-31 plays key roles in the development of cardiac hypertrophy induced by ischemia/hypoxia.This study examined whether miR-31 was involved in the protective role of atorvastatin against CIH-induced myocardial hypertrophy.H9c2 cells were subjected to 8-h intermittent hypoxia per day in the presence or absence of atorvastatin for 5 days.The size of cardiomyocytes,and the expression of caspase 3 and miR-31 were determined by Western blotting and RT-PCR,respectively.MiR-31 mimic or Ro 31-8220,a specific inhibitor of protein kinase C epsilon (PKCε),was used to determine the role of miR-31 in the anti-hypertrophic effect of atorvastatin on cardiomyocytes.PKCε in the cardiomyocytes with miR-31 upregulation or downregulation was detected using RT-PCR and Western blotting.The results showed that CIH induced obvious enlargement of cardiomyocytes,which was paralleled with increased atrial natriuretic peptide (ANP),brain natriuretic peptide (BNP),and slow/beta cardiac myosin heavy-chain (MYH7) mRNA levels.All these changes were reversed by the treatment with atorvastatin.Meanwhile,miR-31 was increased by CIH in vitro.Of note,the atorvastatin pretreatment significantly increased the mRNA and protein expression of PKCε and decreased that of miR-31.Moreover,overexpression of miR-31 abolished the anti-hypertrophic effect of atorvastatin on cardiomyocytes.Upregulation and downregulation of miR-31 respectively decreased and increased the mRNA and protein expression of PKCε.These results suggest that atorvastatin provides the cardioprotective effects against CIH probably via up-regulating PKCε and down-regulating miR-31.
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OBJECTIVES@#To explore the species, quantity and distribution of diatoms in Ningbo three-river watershed during summer and to provide scientific basis for forensic examination of drowning cases in the waters of Ningbo.@*METHODS@#Water samples were collected in July and August of 2015. Fourteen water sampling points were selected from the Yao River, the Fenghua River and the Yong River. The morphological features of diatom species and dominant diatoms were distinguished by microscope.@*RESULTS@#A total of 16 species of diatoms were detected in the Yao River, the Fenghua River and the Yong River. Melosira was the dominant species in the Yao River, and the quantity and richness were higher than in other rivers. The richness of Cyclotella in the Yong River was higher than in other rivers. The richness of Pinnularia and Licmophora were higher in the Fenghua River than in the Yao River and the Yong River.@*CONCLUSIONS@#The species and proportion of diatom is different in each river. Database of the species and relative composition for the diatoms in corresponding river is established, which may provide data support for forensic examination of drowning cases in Ningbo three-river watershed.
Subject(s)
China , Diatoms/classification , Drowning , Rivers , SeasonsABSTRACT
BACKGROUND:Human has a high level heritability in physical performance. With the development of technology and test method in molecular biology, the researchers of sport science are concerned with the influence of gene variation on the elite athlete performance. They begin to know the important value of gene on predicting the physical performance. OBJECTIVE:To review the research results in the field of gene polymorphisms and elite athlete performance and to expatiate the problems in these researches, thereby offering some proposals. METHODS:A computer-based online research of PubMed and CNKI databases was performed to col ect articles published from 1998 to 2013 with the key words“elite athlete performance, gene polymorphisms, endurance, power, training response”in Chinese and English. There were 150 articles after the initial survey. A total of 80 articles were included according inclusion and exclusion criteria. RESULTS AND CONCLUSION:The researches of this field are mainly focused on the three aspects:elite endurance performance, elite power performance, and training response, which are associated with gene polymorphisms. The main genes related to elite endurance performance are ACE, mtDNA, PPAR, ADR, GNB3, NRF2, etc. The main genes related to elite power performance are ACTN3, ACE, GDF-8, IL-6, HIF-1, etc. The main genes related to training response are HBB, TFAM, NRF2, AR, FECH, etc. Several gaps in the current researches have been identified including smal sample size of most athletic cohorts, lack of corroboration with replication cohorts of different ethnic backgrounds. The numerous research findings can be applied to the gene selection of athletes by creating some kinds of algorithms and models.
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<p><b>OBJECTIVE</b>To study the expression of carbonic anhydrase (CA) IX and its significance in molecular subtyping of breast carcinomas. METHODL MaxVision immunohistochemical staining was used to examine the expression of ER, PR, HER2, CK5/6, EGFR, and CA IX in 117 cases of breast invasive ductal carcinomas.</p><p><b>RESULTS</b>The patients' age ranged from 25 to 71 years (mean 49.6 years). All the 117 cases were subclassified into five subtypes, with 66 (56.4%) luminal A, 6(5.1%) luminal B, 10 (8.6%) HER2 positive, 20 (17.1%) basal-like, and 15 (12.8%) unclassified tumors. The expression of CA IX in luminal A and basal-like breast cancers was 13.6% (9/66) and 8/20, respectively, with a significant difference (P < 0.05). Among the luminal A cancers, the expression of CA IX in tumors > 2 cm (7/27, 25.9%) was significantly (P < 0.05) higher than that of tumors ≤ 2 cm (2/39, 5.1%). The expression of CA IX in grade 3 invasive ductal carcinoma (18/50, 36.0%) was significantly higher than that in grade 1 (2/21, 9.5%) and 2 (7/46, 15.2%) tumors (both P = 0.006). In CA IX-negative of invasive ductal carcinoma, the expression of ER and PR was 61.1% (55/90) and 55.6% (50/90), respectively; whereas in CA IX-positive cancers, the expression of ER and PR was 37.0% (10/27) and 29.6% (8/27), respectively. The expression of hormone receptors in CA IX-negative tumors was significantly higher than that in CA IX-positive tumors (for both ER and PR, P < 0.05).</p><p><b>CONCLUSIONS</b>The expression of CA IX correlates not only with molecular subtypes of breast cancer, but also with the grading, hormone receptors and diameter of mammary invasive ductal carcinoma. CA IX is a relative independent marker of poor prognosis in breast cancer.</p>
Subject(s)
Adult , Aged , Female , Humans , Middle Aged , Antigens, Neoplasm , Metabolism , Biomarkers, Tumor , Metabolism , Breast Neoplasms , Classification , Metabolism , Pathology , Carbonic Anhydrase IX , Carbonic Anhydrases , Metabolism , Carcinoma, Ductal, Breast , Classification , Metabolism , Pathology , Neoplasm Grading , Receptor, ErbB-2 , Metabolism , Receptors, Estrogen , Metabolism , Receptors, Progesterone , Metabolism , Tumor BurdenABSTRACT
<p><b>OBJECTIVE</b>To identify the origin and study the morphology of small supernumerary marker chromosome (sSMC) in Turner syndrome with 45, X/46, X, + mar karyotype.</p><p><b>METHODS</b>Using the conventional chromosome G-banding technique, 10 cases of Turner syndrome with 45, X/46, X, + mar chromosome karyotype were obtained, dual-color fluorescence in situ hybridization was applied to study the origin and morphology of the sSMC.</p><p><b>RESULTS</b>In the 10 cases of Turner syndrome with 45, X/46, X, + mar karyotype, the sSMC of 7 cases was derived from X chromosome [sSMC(X)], the sSMC of 2 cases was derived from Y chromosome [sSMC(Y)] and the remaining 1 case was derived from the autosome. There were 4 cases of ring(r) chromosomes and 3 of centric minutes (min) in the 7 sSMC (X) cases. In the 2 sSMC(Y), one case was dicentric (dic) and the other was centric minute (min). The sSMC originated from the autosome was a centric minute (min).</p><p><b>CONCLUSION</b>The origin of sSMC of Turner syndrome with 45, X/46, X, + mar karyotype was almost all from sex chromosomes, and rarely from autosomes. sSMC can exist as isodicentric, ring, or centric minute. The molecular cytogenetic features of the sSMC can provide useful information for genetic counseling, prenatal diagnosis and treatment of the Turner syndrome patients with a 45, X/46, X, + mar karyotype.</p>
Subject(s)
Adolescent , Child , Female , Humans , Chromosome Banding , Chromosomes, Human, X , Genetics , Chromosomes, Human, Y , Genetics , Genetic Markers , In Situ Hybridization, Fluorescence , Karyotyping , Turner Syndrome , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To study the circulation, distribution, and genomic diversity of HPVs in common warts in Beijing area of China.</p><p><b>METHODS</b>Forty eight patients with pathologically diagnosed common warts were screened for the presence of HPV with HPV type-specific PCR and direct sequencing analysis. The genomic diversity of HPVs prevalent in Chinese patients was analyzed based on LCR.</p><p><b>RESULTS</b>Forty one (85.5%) samples were positive for HPV DNA, 13 (31.7%)--HPV-57, 12 (29.3%)--HPV-1a, 7 (17%)--HPV-27 and 5(12.2%)--HPV-2a. Four cases were infected with two different HPV types, two (4.9%) with HPV-1a and HPV-27, one (2.4%) with HPV-1 and HPV-57 and one (2.4%) with HPV-27 and HPV-57. In contrast to the prevalence of single strain of novel HPV-57 variant and HPV-1 prototype, two HPV-2 and three HPV-27 novel variants were found to circulate in Beijing.</p><p><b>CONCLUSION</b>HPV-1, -2, -27 and -57 are predominantly prevalent in patients with common warts in Beijing.</p>
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , China , Epidemiology , DNA, Viral , Genetic Variation , Papillomaviridae , Classification , Genetics , Phylogeny , Prevalence , Warts , Epidemiology , VirologyABSTRACT
<p><b>OBJECTIVE</b>To study the effects of lutein on apoptosis and its mechanism.</p><p><b>METHOD</b>The cells of human esophageal carcinoma EC9706 were grown in RPMI medium containing 10% bovine serum and were treated with lutein at 100 microg x mL(-1) concentration. Flow cytometry was employed to investigate the effects of lutein on cell apoptosis of EC9706 cells. Histochemistry was performed to determine apoptosis-related protein expresion.</p><p><b>RESULT</b>Flow cytometry analyses revealed that lutein increased EC9706 cell apoptosis ratio when treated with lutein 100 microg x mL(-1) at 96 h. Lutein decreased the expression of Bcl-2 protein and increased the expression of Bax protein in EC9706 cells.</p><p><b>CONCLUSION</b>Lutein could inhibit mitosis and stimulate apoptosis of EC9706 cells. The apoptotic effect may result from the down-regulation of expression of Bcl-2 and up-regulation expression of Bax.</p>
Subject(s)
Humans , Antineoplastic Agents, Phytogenic , Pharmacology , Apoptosis , Carcinoma, Squamous Cell , Metabolism , Pathology , Cell Line, Tumor , Esophageal Neoplasms , Metabolism , Pathology , Lutein , Pharmacology , Proto-Oncogene Proteins c-bcl-2 , Metabolism , bcl-2-Associated X Protein , MetabolismABSTRACT
0.05). The average and maximal heart rates of subjects in bench stepping during exercise were higher than those in home stepping (P 0.05), however, the correlation between the direct calculation and home stepping was high (r=0.46, P 0.05).③The correlation between two step experiments for male students was high (r=0.73, P 0.05), however, the difference for female students was significant (P 0.05). CONCLUSION: Two indirect test protocols need further improvements, but home step is more appropriate for a large sample of constitution assessment by comparison of measurement efficiency and precision.
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<p><b>OBJECTIVE</b>To study the resistance and its mechanism of Shigellae spp. to quinolones.</p><p><b>METHODS</b>Seventy-three clinical isolates were collected. Susceptibility tests of pipemidic adcid (PI), ofloxacin (OFL), norfloxacin (NOR), and ciprofloxacin (CIP) were performed in all clinical isolates and Shigella 51573. The N-terminal coding region of gyrA and parC were amplified by polymerase chain reaction (PCR) respectively. Restriction fragment length polymorphism (RFLP) was applied to all PCR procucts of gyrA and parC, and single strand conformational polymorphism analysis (SSCP) was also applied to PCR procucts of parC.</p><p><b>RESULTS</b>The resistance rates for all the Shigella spp. to PI, CIP, NOR and OFL were 79.5%, 60.3%, 41.1% and 36.9%. Sixty-seven strains (91.8%) were quinolone-reduced-sensitive isolates, in which 61 strains (91%) were found carrying mutations in gyrA with 5 strains (7.5%) found carrying mutations in parC. No mutation was found in 6 quinolone-sensitive isolates or Shigella 51573.</p><p><b>CONCLUSION</b>The Shigella spp. had high resistance rates to quinolones. The target gene mutations which were mainly found in gyrA and secondarily in parC, played an important role in the quinolone-resistance in Shigella spp.</p>
Subject(s)
Humans , Anti-Infective Agents , Pharmacology , Ciprofloxacin , Pharmacology , DNA Gyrase , Genetics , DNA Topoisomerase IV , Genetics , Drug Resistance, Bacterial , Genetics , Microbial Sensitivity Tests , Norfloxacin , Pharmacology , Ofloxacin , Pharmacology , Pipemidic Acid , Pharmacology , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Quinolones , Pharmacology , Shigella , GeneticsABSTRACT
In order to study the pathogenesis of HPVl1 and seek for a therapeutic approach of the disease caused by HPV1l. The HPVl1/E2 644bp was amplified by PCR with HPVll plasmid DNA. pGEM-T Easy was used as vector and a clone pTV-644 was obtained.The inserted DNA sequencing was carried out after selecting and identification. According to the hammerhead structure described by Symon's, the possible secondery cleavage sites on HPVll/E2 mRNA were analyzed and the secondery structure of substrate was predicted by computer and ribozyme, excluding analogous sequence of substrate combined with ribozyme were found in the mRNA.The hammerhead ribozyme of RZ2777 against HPV1l/E2 mRNA was seleted to carry out cleavage reaction in vitro. Results of the experiment showed that 644bp substrate derived from HPVll/E2 can be cleavaed site-specifically by ribozyme in vitro. The cleavage activity showed over 85% by choosing the optimun reaction condition, which was not affected by two cis-ribozymes on both 3′-and 5′-ends released by self cleavage,but two flan-king sequences of target RNA influenced the cleavage activity. Results demonstrated that the ribozyme will become a highly effective and specific therapy against HPVll infection.
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Objective To study the role of hematopoietic growth factor(HGF)of placenta chorionic villus in fetal hematopoiesis during embryo ontogeny by observation of the appearance time and the content changes with the fetal growth, which was compared with HGF in cord blood. Methods Thirty embryo villus (2 g each) and 30 cord blood (2 mL each) were collected separately from early pregnant stage(6- 8 weeks), middle pregnant stage(16-22 weeks)and late pregnant stage (37-42 weeks). The levels of HGF were detected by enzyme - linked immunosorbent assay. Results HGF were produced on the early pregnant stage and the content of FL-T3,IL-3 increased gradually.There were significantly differences at different stages(P