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81.
This study aimed to explore the presence of West Nile Virus (WNV) inside four species of mosquitoes: Culex univittatus (Theobald), Culex quinquefasciatus (Say) Aedes vittatus (Bigot) and Aedes vexans (Meigen). Adult wild mosquitoes were collected from different sites: Soba West, Hellat Kuku, Shambat, and Khartoum North Central Live Stock Market (KCLM). Surveys were carried out at Khartoum State during two phases: pre to the rainy season and post to the rainy season. Mosquito specimens were identified using classical keys then preserved at −80 °C freezer for two weeks till the virus examination using polymerase chain reaction (PCR) were carried out. WNV has been detected inside the three species of mosquitoes: A. vexans, C. univittatus, and C. quinquefasciatus. The species were collected from Hellat Kuku, (Shambat and Hellat Kuku), and (Shambat and KCLM) respectively. Two species of mosquitoes were positive for the virus: C. quinquefasciatus and C. univittatus. Positive results for the virus during the first phase of the study; males of C. quinquefasciatus and C. univittatus collected during the second phase of the study were also tested for the existence of the virus and they were positive. For our knowledge this study represents first record of WNV inside wild mosquitoes in Sudan. PCR technique provided reliable information because specific primer-probe sets were used for the detection of the virus. Extra studies are required to incriminate these species of mosquitoes as potential vectors of WNV.  相似文献   
82.
Veronica peduncularis M. Bieb. (Plantaginaceae: Veroniceae) is illustrated and described. A short discussion is provided as to the family affiliations of Veronica, with the proposal that, at least in this article, it is considered to belong to the Plantaginaceae. The infrageneric placement of this taxon is also discussed, but with a commentary suggesting dubious results in an earlier molecular study; its placement in Veronica L. subgenus Pentasepalae (Benth.) M.M.Mart. Ort. & Albach & M.A. Fisch. is commented upon. The species belongs in Veronica subsection Petraea Benth. A full synonymy is provided, together with citation of types, and relevant discussion and notes cover the issues with naming this plant and location of type material. Cultivation and propagation guidelines for the species are provided and current availability of cultivars is outlined.  相似文献   
83.
Perinatal mental health has become a significant focus of interest in recent years, with investment in new specialist mental health services in some high‐income countries, and inpatient psychiatric mother and baby units in diverse settings. In this paper, we summarize and critically examine the epidemiology and impact of perinatal mental disorders, including emerging evidence of an increase of their prevalence in young pregnant women. Perinatal mental disorders are among the commonest morbidities of pregnancy, and make an important contribution to maternal mortality, as well as to adverse neonatal, infant and child outcomes. We then review the current evidence base on interventions, including individual level and public health ones, as well as service delivery models. Randomized controlled trials provide evidence on the effectiveness of psychological and psychosocial interventions at the individual level, though it is not yet clear which women with perinatal mental disorders also need additional support for parenting. The evidence base on psychotropic use in pregnancy is almost exclusively observational. There is little research on the full range of perinatal mental disorders, on how to improve access to treatment for women with psychosocial difficulties, and on the effectiveness of different service delivery models. We conclude with research and clinical implications, which, we argue, highlight the need for an extension of generic psychiatric services to include preconception care, and further investment into public health interventions, in addition to perinatal mental health services, potentially for women and men, to reduce maternal and child morbidity and mortality.  相似文献   
84.
An algal extracellular biopolymer (over 8.5 × 105 Da) composed of carbohydrates (52%) and protein (∼13%) has been isolated from a red alga Rhodella grisea growing in natural conditions by concentration of water medium, alcohol precipitation, dialysis and freeze-drying. This mucilagineous biopolymer contained xylose and its 3-O- and 4-O-methyl derivatives (∼63%), galactose (∼12%), glucuronic acid (11-12%), glucose (∼5%), rhamnose (∼4%), fucose (∼3-4%) and low content of others accompaning sugars. When tested on the citric acid-induced cough and reactivity of airways smooth muscle in vivo in the test system guinea pigs, this biopolymer assigned a significant cough suppressing effect. The reactivity of airways smooth muscle was not affected indicating that expectoration effect was not suppressed by biopolymer application, which is important from the pharmacological point of view.  相似文献   
85.
Denervation leads to muscle atrophy, which is described as muscle mass and force loss, the latter exceeding expectation from mass loss. The objective of this study was to determine the efficiency of angiotensin (Ang) 1–7 at reducing muscle atrophy in mouse extensor digitorum longus (EDL) and soleus following 14- and 28-d denervation periods. Some denervated mice were treated with Ang 1–7 or diminazene aceturate (DIZE), an ACE2 activator, to increase Ang 1–7 levels. Ang 1–7/DIZE treatment had little effect on muscle mass loss and fiber cross-sectional area reduction. Ang 1–7 and DIZE fully prevented the loss of tetanic force normalized to cross-sectional area and accentuated the increase in twitch force in denervated muscle. However, they did not prevent the shift of the force–frequency relationship toward lower stimulation frequencies. The Ang 1–7/DIZE effects on twitch and tetanic force were completely blocked by A779, a MasR antagonist, and were not observed in MasR−/− muscles. Ang 1–7 reduced the extent of membrane depolarization, fully prevented the loss of membrane excitability, and maintained the action potential overshoot in denervated muscles. Ang 1–7 had no effect on the changes in α-actin, myosin, or MuRF-1, atrogin-1 protein content or the content of total or phosphorylated Akt, S6, and 4EPB. This is the first study that provides evidence that Ang 1–7 maintains normal muscle function in terms of maximum force and membrane excitability during 14- and 28-d periods after denervation.  相似文献   
86.
87.
Summary.  The taxonomy, pollination biology, conservation status, cultivation requirements of Dendroseris litoralis are discussed. A colour plate and line drawings are provided for this critically endangered plant from Juan Fernández Island, also known as Robinson Crusoe Island. The media interest generated by this plant is commented on.  相似文献   
88.
2,4-Dianilino pyrimidines are well-known inhibitors of tyrosine kinases including lymphocyte specific kinase (Lck). Structure-activity relationships at the 4-position are discussed and rationalised. Examples bearing a 2-methyl-5-hydroxyaniline substituent at the 4-position were especially potent but showed poor oral pharmacokinetics. Replacement of this substituent by 4-amino(5-methyl-1H-indazole) yielded compounds with comparable enzyme potency and improved pharmacokinetic properties.  相似文献   
89.
Nppa is a cardiac hormone which plays critical roles in regulating salt–water balance. Its expression is restricted to the atria of the healthy post‐natal heart. During heart development, spatio‐temporal expression of Nppa is dynamically changed within the heart and becomes restricted to the atria upon birth. In contrast to its atrial specific expression after birth, Nppa is re‐expressed in the adult ventricles in response to cardiac hypertrophy. To study cardiac chamber specification during development and pathological cardiac remodeling during heart disease, we generated a novel Nppa reporter mouse line by knocking‐in a tagBFP reporter cassette into 3′‐UTR of the Nppa gene without disrupting the endogenous gene. Our results demonstrated dynamic tagBFP expression in the developing heart, recapitulating the spatiotemporal expression pattern of endogenous Nppa. We also found that Nppa‐tagBFP is induced in the ventricle during pathological remodeling. Taken together, Nppa‐tagBFP reporter knock‐in mouse model described in this article will serve as a valuable tool to study cardiac chamber specification during development as well as pathological cardiac remodeling.  相似文献   
90.
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