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Objective: To explore related factors associated with unilateral aldosterone secretion of patients with primary aldosteronism (PA) and construct a predictive model. Methods: The clinical data of patients who were diagnosed as PA in West China Hospital from April 2016 to September 2020 was analyzed retrospectively. According to the results of the adrenal enhancement CT, patients were divided into 3 groups, namely non-nodular group with no bilateral adrenal glands lesions, only with unilateral adrenal hyperplasia or bilateral adrenal hyperplasia, unilateral nodule group with unilateral adrenal nodules and the contralateral adrenal glands with hyperplasia or not, and bilateral nodules group with nodules in both adrenal glands. Regarding the related factors of dominant side of aldosterone secretion, univariate analysis and binary logistic regression were used. Receiver operating characteristic curve and nomogram were used to evaluate the diagnostic performance of regression models. Results: A total of 237 patients with PA were included, of which, 118 males and 119 females, the median age was 39 years, and the body mass index (BMI) was (25.2±3.5) kg/m2. There were 157 (66.2%) of 237 patients with typical imaging findings. There were 32 cases in no-nodular group, 183 cases in unilateral nodule group, and 22 cases in bilateral nodules group. Multivariate analysis showed that age (OR=0.876, P<0.001), blood potassium concentration (OR=0.430, P=0.004), and typical imaging findings (OR=2.202, P=0.035) were associated with unilateral aldosterone secretion. As for unilateral nodule group, multivariate analysis showed that age (OR=0.900, P<0.001), plasma aldosteronism concentration (PAC) (OR=1.050, P=0.018), and typical imaging findings (OR=2.637, P=0.025) were associated with unilateral aldosterone secretion. The agreement rate between the dominant side of the adrenal CT and AVS was only 50.2%. Multivariate analysis showed that age (OR=0.954, P=0.001), BMI (OR=0.893, P=0.024) and PAC (OR=1.043, P=0.011) were independently associated with concordance between AVS and CT. The cut-off value of the ROC curve was 0.43; the model sensitivity was 56.3%; the specificity was 86.7% and the area under the ROC curve was 0.742. Conclusions: Age is an important predictor in the diagnosis of PA subtypes. It is recommended to refer to subgroup based on imaging results for clinical decision. For patients with no obvious lesions or bilateral lesions on CT, AVS should be performed as far as possible to confirm the subtypes in diagnosis of PA.
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Aldosterona , Hiperaldosteronismo , Glândulas Suprarrenais , Adulto , Feminino , Humanos , Hiperaldosteronismo/diagnóstico , Masculino , Curva ROC , Estudos RetrospectivosRESUMO
ABSTRACT: Entomological evidence provides entry points and clues for cases detection, in terms of estimation of the postmortem interval ï¼PMIï¼, and place and cause of death. In recent years, the feasibility of entomological evidence in practice has been proved by theories and cases. It especially plays an important role in the investigation of cases with unnatural death, no monitoring, and highly corrupt cadaver. However, there are still some key issues to be further studied and standardized before the application of entomological evidence to forensic practice, to improve the effect of entomological evidence in forensic investigation and trial. This paper retrospectively reviews key studies of the application of entomological evidence in forensic science, mainly including discussion of forensic entomology inspection standard, identification studies of sarcosaprophagous insect species, collection of sarcosaprophagous insect growth and succession data under different environments and forensic entomotoxicology. With the rapid development of information technology and biotechnology, applying artificial intelligence and whole genome sequencing technology in forensic entomology has become a new research direction, which can improve the application value and range of entomological evidence in forensic science.
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Dípteros , Mudanças Depois da Morte , Animais , Inteligência Artificial , Entomologia , Ciências Forenses , Estudos RetrospectivosRESUMO
ABSTRACT: Objective To identify species of common sarcosaprophagous flies based on digital image analysis of veins, in order to provide new idea for fast and accurate species identification of sarcosaprophagous flies in forensic entomology. Methods Random trapping of 226 male and female sarcosaprophagous flies that comprised of 7 common species, including Sarcophaga peregrina, Parasarcophaga ruficornis, Sarcophaga dux, Seniorwhitea reciproca, Bercaea cruentata, Aldrichina grahami, and Synthesiomysia nudiseta with carrion in the field was conducted. The 17 landmarks on the right wing of each fly were digitally processed and the images were analyzed. The effects of allometry were evaluated using a permutation test. Wing shape variations among 7 sarcosaprophagous fly species and female species was analyzed using canonical variate analysis ï¼CVAï¼. Additionally, cross-validation test was used to evaluate the reliability of classification. Results Among 7 sarcosaprophagous fly species and female species, the effect of allometry had statistical significance ï¼P<0.05ï¼. The CVA results showed that among 7 sarcosaprophagous fly species and female species, differences in the wing shape were significant, and the first two canonical variates accounted for 82.9% and 84.1% of the total variation of vein shape. Vein digital image analysis can be used to separate the 7 common sarcosaprophagous flies, with an overall species identification accuracy of 81.2%-100.0%, and with a species identification accuracy of 75.0%-100.0% to distinguish the female flies of the 7 sarcosaprophagous flies species. Conclusion Vein digital image analysis is a relatively convenient and reliable method for identification of insect species, which can be used for species identification of common sarcosaprophagous flies.
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Dípteros , Animais , Calliphoridae , Feminino , Masculino , Reprodutibilidade dos TestesRESUMO
ABSTRACT: Objective To study the change trend, distribution characteristics and causes of medical malpractices in 18 years, through retrospective analysis of 1 900 cases of medical malpractices, in order to provide guidance for the precaution and the treatment of medical malpractices. Methods A thousand and nine hundred medical malpractice cases that were accepted by Hunan Xiangya Judical Identification Center from 2000 to 2017 were collected. Statistical analysis on the caseloads, the clients, the department distributions, the levels of the hospital and the causes of medical malpractices, etc were conducted. Results The number of cases commissioned by third-party accreditation agencies for medical fault identification was on the rise; The clients of medical malpractices changed significantly in 18 years. Most of the medical malpractice cases occurred in secondary and tertiary hospitals, significantly more in surgery, obstetrics and gynecology. The occurrence of medical malpractices was related to the doctor's insufficient prediction of the severity of the disease and the possible complications, and failure to fully inform the relevant duty of care, etc. Conclusion China's medical malpractice solutions and medical fault identification procedures are gradually improving. Strengthening the medical malpractice precaution awareness of medical workers in surgery, obstetrics and gynecology will be conducive to resolution of medical malpractices.
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Imperícia/tendências , Unidade Hospitalar de Ginecologia e Obstetrícia , Centro Cirúrgico Hospitalar , China , Feminino , Humanos , Gravidez , Estudos RetrospectivosRESUMO
ABSTRACT: In forensic pathology, the estimation of postmortem interval ï¼PMIï¼ has always been a difficult issue, and there is still lack of effective methods to estimate PMI of corpses in water. Microbial biofilm refers to the microbial population attached to non-biological or biological surfaces by microorganisms during microbial growth, that has a three-dimensional structure, surrounded by extracellular polymers and matrix networks created by itself. A series of community succession phenomena of microorganisms occur during the occurrence and development of microbial population. The microbial community and its succession process of this kind of biofilm attached to the surface of a corpse in water may become a new basis for estimation of the PMI of corpses in water. This review elucidates on the concept, classification, research methods, and influencing factors of biofilm and analyzes its application prospects in PMI estimation of corpses in water, which would provide new ideas for the researches in this field.
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Autopsia , Biofilmes , Afogamento , Patologia Legal/métodos , Mudanças Depois da Morte , Cadáver , Humanos , ÁguaRESUMO
Estimation of postmortem interval ï¼PMIï¼ plays a crucial role in forensic study and identification work. Because of the unique anatomy location, vitreous humor is considered to be used for estima- ting PMI, which has aroused interest among scholars, and some researches have been carried out. The detection techniques of vitreous humor are constantly developed and improved which have been gradually applied in forensic science, meanwhile, the study of PMI estimation using vitreous humor is updated rapidly. This paper reviews various techniques and instruments applied to vitreous humor detection, such as ion selective electrode, capillary ion analysis, spectroscopy, chromatography, nano-sensing technology, automatic biochemical analyser, flow cytometer, etc., as well as the related research progress on PMI estimation in recent years. In order to provide a research direction for scholars and promote a more accurate and efficient application in PMI estimation by vitreous humor analysis, some inner problems are also analysed in this paper.
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Autopsia , Patologia Legal/tendências , Mudanças Depois da Morte , Corpo Vítreo/metabolismo , Autopsia/métodos , Autopsia/tendências , Líquidos Corporais , Citometria de Fluxo , Humanos , Potássio , Fatores de TempoRESUMO
Motivated by recent measurement of the magnetism and conductance of the oxygen-assisted Pt nanojunctions, we performed first principle calculations of the magnetic order and electronic transport by explicitly including fully relativistic effects. Our results show that the spin alignment is a cycloidal spiral feature attributed to the Dzyaloshinskii-Moriya interaction, which indicates that the observed magnetism in experiments is of noncollinear nature. The oxygen concentration is the responsible for the switching of the rotational sense of the spiral magnetic order found in oxygen-assisted Pt nanojunctions. Furthermore, the magnetic moments and magnetoresistances vary with oxygen concentration in the chain, which can be used to tune the magnetism and magnetotransport. The oxygen-assisted Pt nanojunctions offer a possibility for spintronic applications in magnetic memory and quantum devices.
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OBJECTIVE: To investigate the effects of erbium:yttrium aluminium garnet (Er:YAG)laser irradiation on pulp and formation of dentin bridge. The beagle dogs' coronal pulp is amputated by Er:YAG laser. METHODS: In the study, 24 premolar teeth of two one-year-old Beagle dogs were used. They were divided into 3 groups: bur group, 200 mJ laser group,100 mJ laser group. The coronal pulp were removed by traditional bur or 200 mJ/20 Hz or 100 mJ/20 Hz Er:YAG laser. Then, they were dressed with mineral trioxide aggregate (MTA) and sealed with resin. Clinical, radiological and histological analyses were performed 1 day, 2 weeks, 4 weeks and 8 weeks after treatment. The mobility and gingiva situation were evaluated for clinical evaluation. Periapical films were used for radiological evaluation. The extracted teeth were preserved in 10% formalin. After decalcification, tissue processing, paraffin embedding, serial sectioning at 5 µm thickness, staining (Hematoxylin and Eosin, HE), the samples were assessed by an independent observer for calcified bridge formation and radicular pulp inflammation. The mean thickness of dental bridge was measured if there was complete dental bridge. RESULTS: Clinical evaluation: there were no signs of fistula or mobility or any abnormal symptoms in Er:YAG laser groups and bur group during the observation period. Radiological evaluation: there were no signs of widened periodontal ligament or root absorption or periapical radiolucency in Er:YAG laser groups and bur group. Histological evaluation: there was no severe inflammation reaction in 200 mJ/20 Hz, 100 mJ/20 Hz Er:YAG laser groups and bur group 1 day, 2 weeks, 4 weeks, 8 weeks post-operation in Hematoxylin and Eosin staining. A complete dentin bridge could be observed in 200 mJ/20 Hz, 100 mJ/20 Hz Er:YAG laser groups, while no complete dentin bridge in bur group 2 weeks post-operation. Complete dental bridge could be observed in each group 4 and 8 weeks post-operation. The mean thickness of dental bridge 4 weeks post-operation in 200 mJ laser group was 77 µm, 100 mJ laser group 87 µm, and bur group 101 µm, and 8 weeks post-operation in 200 mJ laser group was 222 µm,100 mJ laser group 160 µm,and bur group 152 µm. CONCLUSION: The 200 mJ/20 Hz and 100 mJ/20 Hz Er:YAG laser pulpotomies show no harm to radicular pulp and can promote the formation of dentin bridge.
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OBJECTIVE: To investigate the effects of erbium:yttrium aluminium garnet (Er:YAG)laser irradiation on pulp and formation of dentin bridge. The beagle dogs' coronal pulp is amputated by Er:YAG laser. METHODS: In the study, 24 premolar teeth of two one-year-old Beagle dogs were used. They were divided into 3 groups: bur group, 200 mJ laser group,100 mJ laser group. The coronal pulp were removed by traditional bur or 200 mJ/20 Hz or 100 mJ/20 Hz Er:YAG laser. Then, they were dressed with mineral trioxide aggregate (MTA) and sealed with resin. Clinical, radiological and histological analyses were performed 1 day, 2 weeks, 4 weeks and 8 weeks after treatment. The mobility and gingiva situation were evaluated for clinical evaluation. Periapical films were used for radiological evaluation. The extracted teeth were preserved in 10% formalin. After decalcification, tissue processing, paraffin embedding, serial sectioning at 5 µm thickness, staining (Hematoxylin and Eosin, HE), the samples were assessed by an independent observer for calcified bridge formation and radicular pulp inflammation. The mean thickness of dental bridge was measured if there was complete dental bridge. RESULTS: Clinical evaluation: there were no signs of fistula or mobility or any abnormal symptoms in Er:YAG laser groups and bur group during the observation period. Radiological evaluation: there were no signs of widened periodontal ligament or root absorption or periapical radiolucency in Er:YAG laser groups and bur group. Histological evaluation: there was no severe inflammation reaction in 200 mJ/20 Hz, 100 mJ/20 Hz Er:YAG laser groups and bur group 1 day, 2 weeks, 4 weeks, 8 weeks post-operation in Hematoxylin and Eosin staining. A complete dentin bridge could be observed in 200 mJ/20 Hz, 100 mJ/20 Hz Er:YAG laser groups, while no complete dentin bridge in bur group 2 weeks post-operation. Complete dental bridge could be observed in each group 4 and 8 weeks post-operation. The mean thickness of dental bridge 4 weeks post-operation in 200 mJ laser group was 77 µm, 100 mJ laser group 87 µm, and bur group 101 µm, and 8 weeks post-operation in 200 mJ laser group was 222 µm,100 mJ laser group 160 µm,and bur group 152 µm. CONCLUSION: The 200 mJ/20 Hz and 100 mJ/20 Hz Er:YAG laser pulpotomies show no harm to radicular pulp and can promote the formation of dentin bridge.
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Lasers de Estado Sólido , Pulpotomia , Compostos de Alumínio , Animais , Dente Pré-Molar , Compostos de Cálcio , Polpa Dentária , Dentina , Cães , Combinação de Medicamentos , Érbio , Microscopia Eletrônica de Varredura , Óxidos , SilicatosRESUMO
The origin of medical jurisprudence in China can be traced back to as early as 1920s, and since then, the discipline has undergone a great development. This paper, based on the disciplinary development of medical jurisprudence at Xiangya School of Medicine, illustrates its evolution in three aspects covering the scientific and theoretic foundation, legal system and policy support. The current investigation reflected a glimpse of the modern forensic science in China, providing useful historical reference for the development of Chinese forensic science.
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Medicina Legal/história , Medicina Legal/legislação & jurisprudência , China , História do Século XX , História do Século XXI , HumanosRESUMO
OBJECTIVES: To investigate the genetic polymorphisms of 21 short tandem repeat ï¼STRï¼ loci ï¼D3S1358, D13S317, D7S820, D16S539, Penta E, D2S441, TPOX, TH01, D2S1338, CSF1PO, Penta D, D10S1248, D19S433, vWA, D21S11, D18S51, D6S1043, D8S1179, D5S818, D12S391 and FGAï¼. METHODS: A total of 560 blood samples were collected from unrelated healthy individuals of Han population in Hunan Province. Chelex-100 extraction method was applied to the extraction of genomic DNA, and an AGCU EX22 Kit and 9700 STR amplification was used in amplification reactions. The products were separated and analyzed on 310 Genetic Analyzer. RESULTS: A total of 248 alleles were observed, the allelic frequencies ranging from 0.001 to 0.518. Observation of genotype distributions for each locus showed no deviations from Hardy-Weinberg equilibrium except Penta E ï¼P=0.023ï¼. The combined power of discrimination, combined power of exclusion, and combined matching probability of the 21 STR loci were approximately 0.999 999 999 999 999 999 999 999 8, 0.999 999 998, and 1.36×10⻲5, respectively. CONCLUSIONS: The 21 STR loci show high polymorphisms in the Han population, which can provide valuable data and a theoretical basis for forensic individual identification and paternity testing.
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Povo Asiático/genética , Genética Populacional , Repetições de Microssatélites , Polimorfismo Genético , Alelos , China , Impressões Digitais de DNA , Frequência do Gene , Testes Genéticos , Genótipo , Humanos , Reação em Cadeia da Polimerase , ProbabilidadeRESUMO
With the development of molecular identification, there has been a great deal of discussion about the feature of the mitochondrial DNA (mtDNA) fragments. Although longer fragments may minimize stochastic variation across taxa and be more likely to reflect broader patterns of nucleotide divergence, shorter fragments have many advantages, such as quick, easy and economical. Extensive application of long mtDNA segments for species identification cannot always be achieved as a result of constraints in time and money. In the present study, a molecular identification method involving the sequencing of a 272-bp 'barcode' fragment of the mitochondrial cytochrome oxidase subunit I (COI) gene from 55 specimens, representing 7 Chinese sarcophagid species from varying populations, was evaluated. Phylogenetic analysis of the sequenced segments showed that all sarcophagid specimens were properly assigned into seven species, which indicated the possibility of separation congeneric species with the short fragments. The results of this research will be instrumental for the implementation of the Chinese Sarcophagidae database.
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Código de Barras de DNA Taxonômico/métodos , Entomologia/métodos , Ciências Forenses/métodos , Sarcofagídeos/classificação , Sarcofagídeos/genética , Animais , China , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da EspécieRESUMO
Boettcherisca peregrine, as a fly with the necrophagous habits found on human corpses and a vector of disease or parasitic, myiasis-producing agent, is a significant flesh fly species in forensic entomology and medical context. This study reviewed the various aspects of this fly species, including morphology, bionomics, molecular analysis, medical and forensic entomology involvement, such as morphological characteristics of larva, puparia and adult, developmental rate of larvae, the effects of heavy metal (such as Cd and Cu) on the growth and developmentin of larvae, and the impact of some specific stimulis on the labellar chemosensory hair of B. peregrina. Species identification, gene and functions, myiasis and forensic case of this species were also outlined. Therefore, the paper has an important implication for improving the role of B. peregrina in medicine and forensic science.
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Entomological evidence provides valuable information for estimating postmortem interval and location of death in criminal or legal investigations. The colonization of sarcosaphagous insects are commonly discovered in the decomposed corpses in most indoor cases. Therefore, by analyzing the growth patterns and behavioral rhythms of these insects, the application of indoor sarcosaphagous insects in actual cases can be investigated. This study classifies the common species of indoor sarcosaphagous insects and analyzes the characteristics of these insects (such as foraging, oviposition, and growth). It further discusses the effect of micro-environment on their behavior. In addition, the research status of the application of indoor sarcosaphagous insects in forensic investigations is summarized.
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A method employing isolated microspore culture was established for the androgenic embryogenesis of timothy (Phleum pratense L). Embryos/calli were obtained and green plants regenerated. The induction medium was PG-96 (1.0 mg l-1 2,4-D, 0.1 mg l-1 Kinetin) supplemented with 6% maltose monohydrate. Timothy microspore culture was genotype-dependent, among 12 genotypes, 6 produced embryos/calli and 4 produced green plants. Macerating the spikes with a blender and purifying the microspores at a mannitol/maltose monohydrate interface gave a relatively high percentage of cell vitality. The optimum microspore developmental stage was from the very late uninucleate stage to the binucleate stage. Heat shock promoted the initiation of microspore culture. Over 150 regenerated green plants were obtained; in a random sample of 32 of these 65.6% were doubled haploids (6n=42). Albinism was a problem in plant regeneration (9.3-22%). This paper is the first to describe timothy androgenic embryogenesis by isolated microspore culture.
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An isolated microspore culture and green plant regeneration method for rye (Secale cereale L.) was established. Rye isolated microspore androgenesis was genotype-dependent. PG-96M medium supplemented with 6% maltose gave the highest microspore survival rate after 48 h of culture and the highest embryo/callus yield (930 embryos/calli per 100 anthers from cv. Florida 401). Osmotic pressure in the induction medium played an important role. Pretreatment of the anthers with mannitol was beneficial for the microspore culture. Embryos/calli of a relatively younger age and smaller size had a higher regeneration ability, with the best green plant regeneration rate being 6%. Over 150 microspore-derived green plants have been obtained so far. About 90% of the regenerated plants were spontaneous doubled haploids. This is the first report of isolated microspore culture in true rye resulting in androgenic embryogenesis and plant regeneration.
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Overuse of drugs in rural areas of China has led to a growing concern regarding service quality and cost. The study found evidence of high levels of drug use in some rural health facilities in comparison with a number of other developing countries. Such a result was significantly associated with the government policy of financing health care, regulation and monitoring of health services, and users' attitudes and behaviour. It underlines the need for measures to be taken in China to improve drug use in order to allow its population access to effective care at reasonable cost.
PIP: Excessive and inappropriate drug prescribing practices in developing countries expose patients to health risks and raise health costs. In China, the transition to a market-oriented economy has been accompanied by a largely unregulated market for drugs and drug sales represent a major source of income for rural health services. This study examined drug prescribing patterns in 3 poor rural counties in China: Donglan (Guangxi province), Shibing (Guizhou province), and Xunyi (Shaanxi province). For each month in 1993, 100 outpatient records were randomly selected from each county hospital and 50 from each health center for review. A total of 7182 prescriptions (generally for 2-3 drugs) were issued. Between one-third and one-half of all prescriptions were for antibiotics. County health bureaus do not monitor the performance of health workers in relation to drugs unless a medical accident occurs. The income of health workers is directly related to the volume of drugs they sell--a factor that, along with patient equation of drug treatment with effective care, reinforces rampant overprescription. The average cost per prescription in township health centers was equal to 5.6, 2.2, and 6.2 times the average per capita daily income in Donglan, Shibing, and Xunyi, respectively. The mark up at health facility pharmacies was 15% for Western drugs and 20% for Chinese drugs and herbs. These findings indicate an urgent need for policies to end financial incentives for health workers to prescribe drugs, limit the right to prescribe or sell drugs to those with well-defined medical training, and ensure access to effective care at a reasonable cost.
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Prescrições de Medicamentos/estatística & dados numéricos , Padrões de Prática Médica , Serviços de Saúde Rural , China , Prescrições de Medicamentos/economia , Uso de Medicamentos , Custos de Cuidados de Saúde , Humanos , Serviços de Saúde Rural/economia , Serviços de Saúde Rural/estatística & dados numéricosRESUMO
Twenty patients received PolyI:C and twenty patients received inosine in first clinical trial. Final evaluation at 6 months after completion of treatment revealed that SGPT activities fell into normal range or nearly into normal range in 16 (80%) patients of the PolyI:C group and in 8 (40%) patients of the inosine group. These data show that patients treated with PolyI:C have a tendency toward normalization of SGPT activities, but changes of serum HBeAg and DNAP were not significantly different between the two groups. Thirty-five patients were treated with prednisone withdrawal followed by PolyI:C and thirty-five patients received placebo alone in a second clinical trial. Final evaluation at 6 months after completion of treatment revealed that effective rates of reducing serum HBeAg (51.4%) and HBV-DNA (65%) were significantly higher in the treated group than in the control group. It is shown that prednisone withdrawal followed by PolyI:C therapy may be more promising for successful treatment of chronic type B hepatitis than PolyI:C therapy alone.
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Hepatite B/tratamento farmacológico , Poli I-C/uso terapêutico , Prednisona/uso terapêutico , Adulto , Doença Crônica , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Hepatite Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição AleatóriaRESUMO
Since the 1960s, the marshes in the Sanjiang Plain, Northeast China, which are an important reservoir for dissolved carbon, have undergone long-term reclamation to farmland, resulting in elevated marsh loss and degradation on a large scale. This study compared the concentrations of dissolved carbon, as well as the chemical characteristics of dissolved organic carbon (DOC), in natural marshes, a degraded marsh, and drainage ditches sampled during the growing seasons between 2008 and 2010 to clarify the temporal-spatial variability of the dissolved carbon in the fluvial system influenced by the long-term reclamation. The results show that the average concentrations of total dissolved carbon (TDC) and DOC are considerably greater in the natural marshes than in the degraded marsh and drainage ditches. The average DOC concentration for the natural marshes, approximately 35.53 ± 5.15 mg L(-1), is approximately 2.39 times that in the degraded marsh (14.84 ± 4.21 mg L(-1)) and 2.77 times the average value in the ditches (12.84 ± 4.49 mg L(-1)). The dissolved inorganic carbon (DIC) exhibits increased trends in the drainage ditches compared with the natural marshes, whereas the hydrophobic fraction of DOC is present at lower concentrations in the degraded marsh and ditches. Fluorescence indices also indicate that the DOC in the degraded marsh and ditches has a simpler humification structure. In total, the long-term reclamation has led to great variability in the DOC concentration and chemical characteristics in the fluvial system. Changes in the DOC production potential and hydrological regimes due to sustained reclamation are deemed the predominant causes of this effect. The continuously decreased DOC concentration and high variability of DOC in the surface fluvial systems are inevitable if reclamation continues in the Sanjiang Plain. More importantly, the presence of tyrosine and tryptophan-like substances in the ditches indicates that there has been extensive agricultural organic pollution in the fluvial systems. This pollution could lead to more unexpected impacts on the downriver aquatic system. To avoid a destructive ecological crisis in the future, adjustment of the reclamation policy and agricultural management measures in the Sanjiang Plain is urgently needed.
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Exact identification of an insect sample is usually the first essential step in a forensic entomological analysis. However, the morphological similarity of beetles in the level of species usually poses a challenge for forensic scientists within their routine work. As a supplementary to traditional morphological method, molecular genetics identification turns out to be simple and time-saving. A molecular identification method involving a 288-bp segment of the 16S ribosomal RNA (16S rRNA) gene and a 334-bp segment of the cytochrome b (Cyt b) gene from 23 histerid beetles specimens, collected from 7 locations in 6 Chinese provinces, was evaluated. The 16S rRNA and Cyt b genes are sequenced to examine the ability of the region, resolve species identities and enrich the local databases. The monophyletic branches of the phylogenetic tree showed the potential of the markers in identifying beetles within families. Combined analysis is a more accurate approach for species identication than independent analysis.