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21.
Entomological Review - In the forest-steppe of the Middle Volga region, flower thrips, parasitic Hymenoptera and flies Timia abstersa (Ulidiidae) prevailed among the nectar collectors of alfalfa,...  相似文献   
22.
The second part of the paper considers the position of the genus Meromyza Meigen, 1830 in the system of the family Chloropidae, its intrageneric classification, species synonymy, food plants, habitat preferences, geographic distribution of its species, and the faunas of some regions in the Palaearctic. A list of literature is provided.  相似文献   
23.

Background

There are few large published studies of HIV controllers with long-term undetectable viral load (VL). We describe the characteristics and outcomes of 81 French HIV controllers.

Methods and Results

HIV controllers were defined as asymptomatic, antiretroviral-naïve persons infected ≥10 years previously, with HIV-RNA <400 copies/mL in >90% of plasma samples. All available CD4 and VL values were collected at enrolment. Mixed-effect linear models were used to analyze CD4 cell count slopes since diagnosis. HIV controllers represented 0.31% of all patients managed in French hospitals. Patients infected through intravenous drug use were overrepresented (31%) and homosexual men were underrepresented (26% of men) relative to the ANRS SEROCO cohort of subjects diagnosed during the same period. HIV controllers whose VL values were always below the detection limit of the assays were compared with those who had rare “blips” (<50% of VL values above the detection limit) or frequent blips (>50% of VL values above the detection limit). Estimated CD4 cell counts at HIV diagnosis were similar in the three groups. CD4 cell counts remained stable after HIV diagnosis in the “no blip” group, while they fell significantly in the two other groups (−0.26√CD4 and −0.28√CD4/mm3/year in the rare and frequent blip groups, respectively). No clinical, immunological or virological progression was observed in the no blip group, while 3 immunological and/or virological events and 4 cancers were observed in the blip subgroups.

Conclusions

Viral blips in HIV controllers are associated with a significant decline in CD4 T cells and may be associated with an increased risk of pathological events, possibly owing to chronic inflammation/immune activation.  相似文献   
24.
25.
The fauna of grass flies (Diptera: Chloropidae) of the Crimean Peninsula is reviewed for the first time. The study is based on examination of the collection of the Zoological Institute, Russian Academy of Sciences (St. Petersburg), which includes the material collected in Crimea by the authors, the collections of the Zoological Museum of the M. V. Lomonosov Moscow State University and V. I. Vernadsky Crimean Federal University (Simferopol). The annotated list includes 92 species in 34 genera and three subfamilies. Most of the species (61) are recorded from Crimea for the first time. Six species, Chlorops horridus Becker, Ch. puncticornis Loew, Dicraeus (Oedesiella) beschovskii Nartshuk, Lasiosina chandleri Ismay, Meromyza meigeni Nartshuk and Oscinimorpha longirostris (Loew) are recorded for the first time from Russia and Eastern Europe. The characters for distinguishing Oscinimorpha arcuata Duda from O. longirostris (Loew), i.e., the structure of head and the male genitalia, are provided. The boreo-montane species Oscinella vastator (Curtis) and Meromyza curvinervis (Zetterstedt) are found on the Chatyrdag Mountain and Yaila (mostly forestless plateau in the Crimean Mountains). Species with southern European, Mediterranean and Macaronesian-Mediterranean ranges were recorded mostly on the South Coast of Crimea. The Crimean fauna of Chloropidae is compared with the faunas of Sardinia and Turkey.  相似文献   
26.
Echocardiography has the ability to noninvasively explore hemodynamic variables during pharmacologic or exercise stress test in patients with heart failure. In this review, we detail some important potential applications of stress echocardiography in patients with heart failure. In patients with coronary artery disease and chronic LV dysfunction, dobutamine stress echocardiography is able to distinguish between viable and fibrotic tissue to make adequate clinical decisions. Exercise testing, in combination with echocardiographic monitoring, is a method of obtaining accurate information in the assessment of functional capacity and prognosis. Functional mitral regurgitation is a common finding in patients with dilated and ischaemic cardiomyopathy and stress echocardiography in the form of exercise or pharmacologic protocols can be useful to evaluate the behaviour of mitral regurgitation. It is clinical useful to search the presence of contractile reserve in non ischemic dilated cardiomyopathy such as to screen or monitor the presence of latent myocardial dysfunction in patients who had exposure to cardiotoxic agents. Moreover, in patients with suspected diastolic heart failure and normal systolic function, exercise echocardiography could be able to demonstrate the existence of such dysfunction and determine that it is sufficient to limit exercise tolerance. Finally, in the aortic stenosis dobutamine echocardiography can distinguish severe from non-severe stenosis in patients with low transvalvular gradients and depressed left ventricular function.  相似文献   
27.

Background

Tumour cells show greater dependency on glycolysis so providing a sufficient and rapid energy supply for fast growth. In many breast cancers, estrogen, progesterone and epidermal growth factor receptor-positive cells proliferate in response to growth factors and growth factor antagonists are a mainstay of treatment. However, triple negative breast cancer (TNBC) cells lack receptor expression, are frequently more aggressive and are resistant to growth factor inhibition. Downstream of growth factor receptors, signal transduction proceeds via phosphatidylinositol 3-kinase (PI3k), Akt and FOXO3a inhibition, the latter being partly responsible for coordinated increases in glycolysis and apoptosis resistance. FOXO3a may be an attractive therapeutic target for TNBC. Therefore we have undertaken a systematic review of FOXO3a as a target for breast cancer therapeutics.

Methods

Articles from NCBI were retrieved systematically when reporting primary data about FOXO3a expression in breast cancer cells after cytotoxic drug treatment.

Results

Increased FOXO3a expression is common following cytotoxic drug treatment and is associated with apoptosis and cell cycle arrest. There is some evidence that metabolic enzyme expression is also altered and that this effect is also elicited in TNBC cells. FOXO3a expression serves as a positive prognostic marker, especially in estrogen (ER) receptor positive cells.

Discussion

FOXO3a is upregulated by a number of receptor-dependent and -independent anti-cancer drugs and associates with apoptosis. The identification of microRNA that regulate FOXO3a directly suggest that it offers a tangible therapeutic target that merits wider evaluation.  相似文献   
28.
29.
Entomological Review - New data are given on distribution and bird host associations of two species of the louse fly genus Ornithophila Rondani, 1878 in Eastern Europe and North Asia. Ornithophila...  相似文献   
30.
Hymenopterous parasitoids of grass flies of the family Chloropidae from the Palaearctic and Nearctic regions are reviewed. These parasitoids belong to four superfamilies and 16 families of Hymenoptera and were reared from 39 species of Chloropidae in the Palaearctic (less than 6% of the fauna) and only from 10 species in the Nearctic Region. The majority of parasitoids are oligo-or polyphagous species. To a certain degree, the parasitoids are specialized on one of the three host groups: (1) species developing in shoots of cereal and meadow grasses; (2) forest species developing in cones of coniferous trees; and (3) species associated with the common reed, Phragmites australis. In the Palaearctic Region, the majority of parasitoids (91 species) were reared from Oscinella frit L. s. 1.; a significantly smaller number of these parasites is known from this host in the Nearctic Region, nearly half of the parasitoids being common for both regions. The next large group of parasitoids is associated with gall-inducing species of the genus Lipara Meigen (59 species) developing in the common reed. By contrast with two other groups of parasitoids, this one includes many species of the family Ichneumonidae. It should be noted that taxonomic diversity at the third trophic level is markedly greater than at the second level.  相似文献   
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