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Coronaviruses (CoV) are widely distributed pathogens of human and animals and can cause mild or severe respiratory and gastrointestinal disease. Antigenic and genetic similarity of some CoVs within the Betacoronavirus genus is evident. Therefore, for the first time in Slovenia, we investigated the genetic diversity of partial 390-nucleotides of RNA-dependent-RNA polymerase gene (RdRp) for 66 human (HCoV) and 24 bovine CoV (BCoV) positive samples, collected between 2010 and 2016 from human patients and cattle with respiratory disease. The characterized CoV strains belong to four different clusters, in three separate human clusters HCoV-HKU1 (n = 34), HCoV-OC43 (n = 31) and HCoV 229E (n = 1) and bovine grouping only as BCoVs (n = 24). BCoVs from cattle and HCoV-OC43 were genetically the most closely related and share 96.4–97.1% nucleotide and 96.9–98.5% amino acid identity.  相似文献   

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To investigate the epidemiology and factors associated with the severity of viral acute lower respiratory infection (ALRI) in children hospitalized in Manaus, Amazonas, in 2017 to 2018.Retrospective cohort study of children hospitalized at the Hospital and Emergency Room Delphina Rinaldi Abdel Aziz, in Manaus, from April 01, 2017 to August 31, 2018, with a clinical diagnosis of ALRI and nasopharyngeal aspirates positive for at least 1 respiratory virus.One hundred forty-six children aged 0.2 to 66 months (median 7 months) were included. Patients were divided into 2 groups according to the disease severity classified by an adapted Walsh et al score: moderate disease, score 0–4, n = 66 (45.2%) and severe disease, score 5–7, n = 80 (54.8%). A greater number of viral ALRI cases were observed in the rainiest months. Respiratory syncytial virus was the most prevalent (n = 103, 70.3%), followed by metapneumovirus (n = 24, 16.4%), influenza virus (n = 17, 11.6%), parainfluenza virus (n = 11, 7.5%), and adenovirus (n = 4, 2.7%). Co-detections of 2 to 3 viruses were found in 12 (8.2%) patients. The presence of viral coinfection was an independent risk factor for disease severity (adjusted relative risk [RR] 1.53; 95% CI 1.10–2.14). Twelve patients (8.2%) died, all with severe disease. Risk factors for death were shock (adjusted RR 10.09; 95% CI 2.31–43.90) and need for vasoactive drugs (adjusted RR 10.63; 95% CI 2.44–46.31).There was a higher incidence of viral ALRI in Manaus in the rainy season. Respiratory syncytial virus was the most prevalent virus. The presence of viral coinfection was an independent risk factor for disease severity.  相似文献   

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The luteinizing hormone (LH) activity of pituitary glands from three orders of Reptilia was studied by means of the induction of ovulation in vitro from the ovaries of the frogs Hyla regilla and Xenopus laevis. Representatives from several families including both suborders of Chelonia (turtles) and several Crocodilia had relatively high concentrations of LH activity in the pituitary. In contrast, ovulation could not be induced with pituitaries from any of the Squamata (snakes and lizards) tested, although these glands had high levels of gonadotropins in other bioassays. Thus, there appears to be a major dichotomy between Squamata and other reptiles either in the levels at which LH is stored in the gland, in the structure of the LH molecule, or in whether LH exists. The lack of bioassayable LH in snakes and lizards distinguishes them from all other orders of tetrapods examined.Previous cytological studies of the reptilian pituitary indicated a regional distribution of LH-cells (luteotropes), but measurement of LH in different regions of the pars distalis from three families of turtles revealed a uniform distribution of this hormonal activity.  相似文献   

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The incidence of watermelon chlorotic stunt disease and molecular characterization of the Palestinian isolate of Watermelon chlorotic stunt virus (WmCSV-[PAL]) are described in this study. Symptomatic leaf samples obtained from watermelon Citrullus lanatus (Thunb.), and cucumber (Cucumis sativus L.) plants were tested for WmCSV-[PAL] infection by polymerase chain reaction (PCR) and Rolling Circle Amplification (RCA). Disease incidence ranged between 25%–98% in watermelon fields in the studied area, 77% of leaf samples collected from Jenin were found to be mixed infected with WmCSV-[PAL] and SLCV. The full-length DNA-A and DNA-B genomes of WmCSV-[PAL] were amplified and sequenced, and the sequences were deposited in the GenBank. Sequence analysis of virus genomes showed that DNA-A and DNA-B had 97.6%–99.42% and 93.16%–98.26% nucleotide identity with other virus isolates in the region, respectively. Sequence analysis also revealed that the Palestinian isolate of WmCSV shared the highest nucleotide identity with an isolate from Israel suggesting that the virus was introduced to Palestine from Israel.  相似文献   

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目的 了解鼻病毒在婴幼儿疑似甲型H1N1重症病例及门诊流感样病例中的分布、分子进化特征,及与其他呼吸道病毒的合并感染情况。方法 样本有两种来源:疑似甲流重症病例样本246份为样本1组,门诊流感样病例样本68份为样本2组。扩增鼻病毒5’非编码区及VP2-VP4区,测序比对,构建进化树。对鼻病毒阳性样本检测其他常见呼吸道病毒。结果 样本1组中鼻病毒阳性率为8.54%(21/246)。样本2组中鼻病毒阳性率为16.2%(11/68)。样本1组和样本2组鼻病毒与其他呼吸道病毒的合并感染率分别为71.4%、9.09%,两者具有显著性差异(P<0.05)。对其中14份样本成功进行了测序,HRV-A、HRV-B、HRV-C基因型所占比例分别为64.3%、7.1%和28.6%。多序列比对分析表明鼻病毒3个基因型间的核苷酸序列一致性为55%~65%。结论 HRV在疑似甲型H1N1流感重症病例中主要是以合并感染为主。杭州地区婴幼儿疑似甲型H1N1流感重症病例及门诊流感样病例中鼻病毒感染主要是以HRV-A,HRV-C基因型为主,HRV各型别之间核苷酸变异较大。  相似文献   

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Reptiles have gained popularity in the North American and European pet trade. Large numbers of captive-born veiled chameleons, Chamaeleo calyptratus, are produced annually but knowledge of their reproductive cycle has been limited to anecdotal observations. This study describes the hormonal changes associated with reproductive cycling in female veiled chameleons using non-invasive fecal evaluation of metabolites of the three principal ovarian steroids, estradiol (E2), testosterone (T), progesterone (P), and their metabolites, by enzyme immunoassays. The hormone patterns were compared with follicular development and ovulation as determined by magnetic resonance imaging (MRI). Three main cycle stages were identified on MRI: the previtellogenic stage (PV) with the absence of visible follicular structures, vitellogenic stage (V) with the presence of round follicular structures >2 mm diameter, and the gravid stage with the presence of oval egg structures. Although the absolute values of the baselines and peaks for each hormone varied among animals, approximately 24-fold increases over mean P baseline values and 7.5-fold increases over mean E2 and T baseline values were associated with biological events. E2 rose during vitellogenesis, peaked in late vitellogenesis and fell shortly thereafter. P rose during the late vitellogenic stage, peaked in mid-gravidity and fell to baseline values at oviposition. Ovulation occurred with the decreasing E2:P ratio. T levels varied during the pre- and vitellogenic stages then mirrored P with a distinct peak during the time of ovulation and gravidity. These data provides us with the necessary background for future studies on the reproductive biology of this species.  相似文献   

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The Cretaceous–Paleogene (K-Pg) boundary is marked by a major mass extinction, yet this event is thought to have had little effect on the diversity of lizards and snakes (Squamata). A revision of fossil squamates from the Maastrichtian and Paleocene of North America shows that lizards and snakes suffered a devastating mass extinction coinciding with the Chicxulub asteroid impact. Species-level extinction was 83%, and the K-Pg event resulted in the elimination of many lizard groups and a dramatic decrease in morphological disparity. Survival was associated with small body size and perhaps large geographic range. The recovery was prolonged; diversity did not approach Cretaceous levels until 10 My after the extinction, and resulted in a dramatic change in faunal composition. The squamate fossil record shows that the end-Cretaceous mass extinction was far more severe than previously believed, and underscores the role played by mass extinctions in driving diversification.  相似文献   

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The results of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid as one of the criteria has been widely applied to assess whether the coronavirus disease 2019 (COVID-19) patients could discharge, however, the risk factors that affect the duration of the SARS-CoV-2 clearance remained to be an enigma. Our research was to identify risk factors correlated with prolonged duration of the SARS-CoV-2 clearance in moderate COVID-19 patients.We retrospectively analyzed 279 consecutive ordinary COVID-19 patients in 3 hospitals in Hubei province including Huangshi Hospital of Infectious Disease, Wuhan Thunder God Mountain Hospital, and Tongji Hospital. Eight clinical characters were contained as risk factors. We used a logistic regression model and nomogram to assess the possibility that the SARS-CoV-2 nucleic acid may turn negative in 14 days.Time from symptoms onset to diagnosis (odds ratio [OR] = 3.18; 95% confidence interval [CI] 1.56–6.46; P = .001), time from onset use of antiviral drugs to onset of symptoms (OR = 0.41; 95% CI 0.23–0.72; P = .02), and bacterial coinfection (OR = 0.07; 95% CI 0.01–0.86; P = .038) were independent risks factors for the duration of SARS-CoV-2 nucleic acid clearance. The regression model showed good accuracy and sensitivity (area under the curve  = 0.96). Nomogram was also provided to predict the negative conversion rate of SARS-CoV-2 nucleic acids within 14 days.Time from symptoms onset to diagnosi, time from onset use of antiviral drugs to onset of symptoms, and bacterial coinfection were independent risk factors for the time of SARS-CoV-2 nucleic acid turning negative in ordinary COVID-19 patients. However, the age, gender, underlying disease, fungal coinfection, and duration use of antiviral drugs were irrelevant factors.  相似文献   

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Porcine respirovirus 1 (PRV1) is also known as porcine parainfluenza virus 1 (PPIV1). The prevalence and the role of PRV1 infections for pig health is largely unknown. In order to assess the PRV1 prevalence in Poland, nasal swabs and oral fluids collected from pigs from 30 farms were examined with RT real-time PCR. Additionally, IAV and PRRSV infection statuses of PRV1-positive samples were examined. The results showed that the virus is highly prevalent (76.7% farms positive) and different patterns of PRV1 circulation in herds with mild–moderate respiratory disease were observed. Co-infections with IAV and PRRSV were infrequent and detected in 8 (23.5%) and 4 (11.8%) out of 34 PRV1-positive nasal swab pools from diseased pens, respectively. In one pen PRV1, IAV, and PRRSV were detected at the same time. Interestingly, PRV1 mean Ct value in samples with co-infections was significantly lower (29.8 ± 3.1) than in samples with a single PRV1 infection (32.5 ± 3.6) (p < 0.05), which suggested higher virus replication in these populations. On the other hand, the virus detection in pig populations exhibiting respiratory clinical signs, negative for PRRSV and IAV, suggests that PRV1 should be involved in differential diagnosis of respiratory problems.  相似文献   

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It is well-known that microRNAs are able to regulate the expression of target mRNAs through complementary base-pairing to their 3′-untranslated regions (3′UTR) sequences. This study aimed to investigate whether single nucleotide polymorphisms resided in the 3′UTR sequences in patients with chronic hepatitis B viruses (HBV) infection are associated with the development and metastasis of hepatocellular carcinoma (HCC). Seventeen single nucleotide polymorphisms in the 3′UTR sequence of 10 genes regulated or affected by hepatitis B virus X protein were found by bioinformatics methods. Two hundred fifteen patients with HBV-related HCC and 216 patients with chronic HBV infection were recruited. Through case-control study, only found that the von Hippel-Lindau gene rs1642742 (G>A) may be associated with the occurrence and metastasis of HCC. The ORs of the frequencies of rs1642742 A allele versus G allele were 1.424 (P = .038, 95% confidence interval [CI] = 1.019–1.989) between HBV-related HCC and chronic HBV infection group and were 2.004 (P = .037, 95%CI = 1.031–3.895) between tumor metastasis and non-metastasis group, respectively. Through multivariate regression analysis, we also found that rs1642742 AA genotype was an independent risk factor for tumor metastasis (odds ratio = 2.227, 95% CI = 1.043–4.752, P = .038) in HBV-related HCC group. Our study suggested that Von Hippel-Lindau rs1642742 contributed to susceptibility to developing HCC and correlated with tumor metastasis.  相似文献   

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The hemorrhagic disease of grass carp (HDGC) caused by grass carp reovirus (GCRV) still poses a great threat to the grass carp industry. Isolation and identification of the GCRV genotype I (GCRV-I) has been rarely reported in the past decade. In this study, a new GCRV was isolated from diseased fish with severe symptoms of enteritis and mild hemorrhages on the body surface. The isolate was further identified by cell culture, transmission electron, indirect immunofluorescence, and SDS-PAGE electrophoretic pattern analysis of genomic RNA. The results were consistent with the new isolate as a GCRV-I member and tentatively named GCRV-GZ1208. Both grass carp and rare minnow infected by the GCRV-GZ1208 have no obvious hemorrhagic symptoms, and the final mortality rate was ≤10%, indicating that it may be a low virulent isolate. GZ1208 possessed highest genomic homology to 873/GCHV (GCRV-I) and golden shiner reovirus (GSRV). Additionally, it was found a 90.7–98.3% nucleotide identity, a 96.4–100% amino acid identity, and <50% identity with GCRV-II and III genotypes. Interestingly, the sequences of some segments of GZ1208 were similar to GCRV-8733/GCHV, whereas the remaining segments were more closely related to GSRV, suggesting that a recombination event had occurred. Bootscan analysis of the complete genomic sequence confirmed this hypothesis, and recombination events between 873/GCHV and other GSRV-like viruses were also accompanied by gene mutations.  相似文献   

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Bacterial coinfection represents a major cause of morbidity and mortality in epidemics of influenza A virus (IAV). The bacterium Haemophilus influenzae typically colonizes the human upper respiratory tract without causing disease, and yet in individuals infected with IAV, it can cause debilitating or lethal secondary pneumonia. Studies in murine models have detected immune components involved in susceptibility and pathology, and yet few studies have examined bacterial factors contributing to coinfection. We conducted genome-wide profiling of the H. influenzae genes that promote its fitness in a murine model of coinfection with IAV. Application of direct, high-throughput sequencing of transposon insertion sites revealed fitness phenotypes of a bank of H. influenzae mutants in viral coinfection in comparison with bacterial infection alone. One set of virulence genes was required in nonvirally infected mice but not in coinfection, consistent with a defect in anti-bacterial defenses during coinfection. Nevertheless, a core set of genes required in both in vivo conditions indicated that many bacterial countermeasures against host defenses remain critical for coinfection. The results also revealed a subset of genes required in coinfection but not in bacterial infection alone, including the iron-sulfur cluster regulator gene, iscR, which was required for oxidative stress resistance. Overexpression of the antioxidant protein Dps in the iscR mutant restored oxidative stress resistance and ability to colonize in coinfection. The results identify bacterial stress and metabolic adaptations required in an IAV coinfection model, revealing potential targets for treatment or prevention of secondary bacterial pneumonia after viral infection.The bacterium Haemophilus influenzae is a Gram-negative inhabitant of the human upper respiratory tract and a common agent in sinusitis, otitis media, lung infections in cystic fibrosis, and exacerbations of chronic obstructive pulmonary disease (COPD). In the context of prior infection by influenza A virus (IAV), H. influenzae is associated with secondary bacterial pneumonia (1). Annually, influenza and related complications cause ∼36,000 deaths, over 200,000 hospitalizations in the United States, and ∼5 million cases of severe illness worldwide (2, 3). Uncomplicated IAV infection can progress to pneumonia; however, secondary bacterial infection combined with viral infection is commonly the major cause of excess morbidity and mortality during epidemics and pandemics. For example, the 1918 influenza pandemic killed an estimated 50 million people worldwide, and the majority of deaths have been attributed to bacterial secondary infections in which Streptococcus pneumoniae, H. influenzae, and Staphylococcus spp. represent the most common isolates (1). β-Lactam antibiotics are commonly used for treatment, and yet ∼30% of H. influenzae isolates are β-lactamase–positive (46). Because of increasing levels of bacterial antibiotic resistance, and the continued threat of global pandemics with potential emergence of new IAV subtypes, combined IAV and bacterial infection remains a significant public health concern.In 1945, Francis and Vicente de Torregrosa demonstrated lethality of H. influenzae when introduced into the lungs of mice after infection with IAV (7). More recently, pathogenic mechanisms associated with the mouse lung model of lethal IAV coinfection with H. influenzae type b (Hib) were investigated, implicating innate immunity in disease progression (8). Coinfection did not influence viral titers and yet led to dramatically increased multiplication and persistence of bacteria. Viral enhancement of host susceptibility to bacterial infection has been examined in coinfection models with diverse bacteria, implicating modification of mucosal surfaces and dysfunctional immune responses that prevent bacterial containment including altered phagocytic capacity, defective TLR responses, and enhanced pro- and anti-inflammatory cytokine production, and decreased tolerance to tissue damage (914). In contrast, bacterial factors involved in coinfection have received less attention. There have been no systematic studies to identify such factors, and genes of H. influenzae involved in IAV coinfection have not been identified.We investigated the hypothesis that H. influenzae possesses genes that promote its ability to survive host defenses and exploit conditions in the lung generated by coinfection with IAV. Using a genome-scale analytical approach, we simultaneously monitored fitness of thousands of transposon mutants in the murine lung model in the presence and absence of prior IAV infection. The results reveal a core set of bacterial genes required in both models, as well as genes required uniquely in one environment but not the other. Coinfection altered bacterial requirements for known virulence genes conferring not only immune evasion properties but also those encoding regulatory factors and physiological pathways. Therefore, genome-wide analysis of the fitness of bacterial mutants serves as a probe for conditions created during bacterial/viral coinfection of murine lung and identifies bacterial adaptations that specifically promote their multiplication in this pathogenic context.  相似文献   

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BackgroundViral respiratory infections are one of the main causes of hospitalization in children. Even if mortality rate is low, 2% to 3% of the hospitalized children need mechanical ventilation. Risk factors for admission to the pediatric intensive care unit (PICU) are well known, while few studies have described risk factors for invasive ventilator support and prolonged hospitalization.MethodsA retrospective study including all patients aged between 2 and 18 months with a confirmed viral respiratory infection, requiring admission to PICU from September to March between 2015 and 2019, was conducted at Bambino Gesù Children''s Hospital in Rome, Italy.ResultsOne hundred ninety patients were enrolled, with a median age of 2.7 months; 32.1% had at least one comorbidity, mainly prematurity. The most frequent isolated viruses were RSV‐B, rhinovirus, and RSV‐A; 38.4% needed mechanical ventilation. This subgroup of patients had lower median birth weight compared with patients not requiring mechanical ventilation (2800 g vs. 3180 g, p = 0.02); moreover, comorbidities were present in 43.8% of intubated patients and in 24.8% of patients treated with non‐invasive ventilation (p = 0.006). Viral coinfection did not result to be a risk factor for mechanical support, while virus–bacteria coinfection was significantly associated with mechanical ventilation (p < 0.001). Similar risk factors were identified for prolonged hospitalization.ConclusionsEarly identification of patients who could have a sudden respiratory deterioration and need of mechanical ventilation is crucial to reduce complications due to orotracheal intubation and prolonged hospitalization in PICU. Further studies are needed to define high‐risk group of patients and to design targeted interventions.  相似文献   

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We aim to construct a diagnostic model for bacterial coinfection in dengue patients (Dengue Dual Infection Score [DDIS]); 2,065 adult dengue patients (mean age = 41.9 ± 17.2 years, 58.4% male, 83 patients with bacterial coinfection) seen at a university hospital from January of 2005 to February of 2010 were studied. The DDIS was created by assigning one point to each of five risk factors for bacterial coinfection: pulse rate ≥ 90 beats/minute, total white cell count ≥ 6 × 109/L, hematocrit < 40%, serum sodium < 135 mmol/L, and serum urea ≥ 5 mmol/L. The DDIS identified bacterial coinfection (derivation set area under the curve = 0.793, 95% confidence interval = 0.732–0.854; validation set area under the curve = 0.761, 95% confidence interval = 0.637–0.886). A DDIS of ≥ 4 had a specificity of 94.4%, whereas a DDIS of ≥ 1 had a sensitivity of 94.4% for bacterial coinfection. The DDIS can help to select dengue patients for early bacterial cultures and empirical antibiotics.  相似文献   

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Background:There is no definite conclusion about comparison of better effectiveness between N95 respirators and medical masks in preventing health-care workers (HCWs) from respiratory infectious diseases, so that conflicting results and recommendations regarding the protective effects may cause difficulties for selection and compliance of respiratory personal protective equipment use for HCWs, especially facing with pandemics of corona virus disease 2019.Methods:We systematically searched MEDLINE, Embase, PubMed, China National Knowledge Infrastructure, Wanfang, medRxiv, and Google Scholar from initiation to November 10, 2020 for randomized controlled trials, case-control studies, cohort studies, and cross-sectional studies that reported protective effects of masks or respirators for HCWs against respiratory infectious diseases. We gathered data and pooled differences in protective effects according to different types of masks, pathogens, occupations, concurrent measures, and clinical settings. The study protocol is registered with PROSPERO (registration number: 42020173279).Results:We identified 4165 articles, reviewed the full text of 66 articles selected by abstracts. Six randomized clinical trials and 26 observational studies were included finally. By 2 separate conventional meta-analyses of randomized clinical trials of common respiratory viruses and observational studies of pandemic H1N1, pooled effects show no significant difference between N95 respirators and medical masks against common respiratory viruses for laboratory-confirmed respiratory virus infection (risk ratio 0.99, 95% confidence interval [CI] 0.86–1.13, I2 = 0.0%), clinical respiratory illness (risk ratio 0.89, 95% CI 0.45–1.09, I2 = 83.7%, P = .002), influenza-like illness (risk ratio 0.75, 95% CI 0.54–1.05, I2 = 0.0%), and pandemic H1N1 for laboratory-confirmed respiratory virus infection (odds ratio 0.92, 95% CI 0.49–1.70, I2 = 0.0%, P = .967). But by network meta-analysis, N95 respirators has a significantly stronger protection for HCWs from betacoronaviruses of severe acute respiratory syndrome, middle east respiratory syndrome, and corona virus disease 2019 (odds ratio 0.43, 95% CI 0.20–0.94).Conclusions:Our results provide moderate and very-low quality evidence of no significant difference between N95 respirators and medical masks for common respiratory viruses and pandemic H1N1, respectively. And we found low quality evidence that N95 respirators had a stronger protective effectiveness for HCWs against betacoronaviruses causative diseases compared to medical masks. The evidence of comparison between N95 respirators and medical masks for corona virus disease 2019 is open to question and needs further study.  相似文献   

18.
It is widely recognized that hypertension is one of the major risk factor for disease severity and mortality in patients with coronavirus disease 2019 (COVID‐19). However, type 2 diabetes mellitus (T2DM) and hypertension are frequent comorbid conditions, complicating the assessment of hypertension''s individual contribution to the risk. The aims of this study were to evaluate the contributions of hypertension alone, T2DM alone, or their combination to the risk of death, acute respiratory distress syndrome (ARDS)/respiratory failure, and severe COVID‐19 infection. Additionally, we assessed risks associated with elevated blood pressure and fasting blood glucose on the same three clinical outcomes. Multivariate logistic models were used for these analyses. Among the 3400 patients, 3327(97.9%) survived and 73(2.1%) died. Compared to patients having neither hypertension nor T2DM (n = 1392), the risk of mortality was significantly higher in patients with T2DM alone (n = 226, OR 5.26 [95% CI: 2.39–11.58]) or with T2DM in combination with hypertension (n = 507, OR 3.02, [95% CI: 1.48–6.15]). Similarly, T2DM was a risk factor for development of ARDS/respiratory failure and severe infection. Hypertension alone (n = 1275) only conferred additional risk for the development of severe infection (OR 1.22 [95% CI: 1.00–1.51]). In conclusion, neither hypertension nor elevated blood pressure was independent risk factors for death or ARDS/respiratory failure but hypertension marginally increased the risk of severe COVID‐19 infection. The risk associated with hypertension is accentuated through its confounding effect on T2DM.  相似文献   

19.
Changes in plasma progesterone, testosterone, and estradiol-17β in serially bled female snakes (Natrix fasciata) and female turtles (Chrysemys picta) in response to single iv injections of ovine LH or FSH were measured by RIA. In snakes, both FSH and LH increased the levels of all three steroids in plasma, though considerable individual variation in response to either hormone was encountered. The apparent differences in the responses to the gonadotropins may have been due to differences in the stage of follicular development in different animals. In contrast, in female turtles, ovine FSH was clearly most active in stimulating steroid (testosterone and estradiol) synthesis, although LH has a consistent, though minor, stimulatory effect on estradiol secretion 30 min after injection. Neither hormone stimulated progesterone secretion at the time of year tested. In snakes, but not in turtles, it was possible to correlate preinjection plasma levels of estradiol with the stage of follicular development, high levels of hormone being found in animals with large follicles and low levels in animals with small follicles.  相似文献   

20.
BackgroundThere is a limited amount of data in China on the disease burden of respiratory syncytial virus‐ (RSV) associated acute lower respiratory infection (ALRI) among young children. This study aimed to estimate the hospitalization rate of RSV‐associated ALRI (RSV‐ALRI) among children aged 0–59 months in Suzhou, China.MethodsAll cases from children hospitalized with ALRI who were aged 0–59 months in Suzhou University Affiliated Children''s Hospital during January 2010 to December 2014 were retrospectively identified. Detailed diagnosis and treatment data were collected by reviewing each individual''s medical chart. In accordance with the World Health Organization (WHO) influenza disease burden estimation, the hospitalization rate of RSV‐ALRI among children aged 0–59 months in Suzhou, China, was then estimated.ResultsOut of the 28,209 ALRI cases, 19,317 (68.5%) were tested for RSV, of which the RSV positive proportion was 21.3% (4107/19,317). The average hospitalization rate of RSV‐ALRI for children aged 0–59 months was 14 (95% confidence interval [CI]:14–14)/1000 children years, and that for children aged 0–5, 6–11, 12–23, and 24–59 months were 70 (95% CI: 67–73), 31 (95% CI: 29–33), 11 (95% CI: 10–12), and 3 (95% CI: 3–3)/1000 children years, respectively.ConclusionA considerable degree of RSV‐ALRI hospitalization exists among children aged 0–59 months, particularly in those under 1 year of age. Therefore, an effective monoclonal antibody or vaccine is urgently needed to address the substantial hospitalization burden of RSV infection.  相似文献   

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