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161.
Substance use disorders (SUDs) are highly prevalent and exact a large toll on individuals’ health, well-being, and social functioning. Long-lasting changes in brain networks involved in reward, executive function, stress reactivity, mood, and self-awareness underlie the intense drive to consume substances and the inability to control this urge in a person who suffers from addiction (moderate or severe SUD). Biological (including genetics and developmental life stages) and social (including adverse childhood experiences) determinants of health are recognized factors that contribute to vulnerability for or resilience against developing a SUD. Consequently, prevention strategies that target social risk factors can improve outcomes and, when deployed in childhood and adolescence, can decrease the risk for these disorders. SUDs are treatable, and evidence of clinically significant benefit exists for medications (in opioid, nicotine and alcohol use disorders), behavioral therapies (in all SUDs), and neuromodulation (in nicotine use disorder). Treatment of SUDs should be considered within the context of a Chronic Care Model, with the intensity of intervention adjusted to the severity of the disorder and with the concomitant treatment of comorbid psychiatric and physical conditions. Involvement of health care providers in detection and management of SUDs, including referral of severe cases to specialized care, offers sustainable models of care that can be further expanded with the use of telehealth. Despite advances in our understanding and management of SUDs, individuals with these conditions continue to be stigmatized and, in some countries, incarcerated, highlighting the need to dismantle policies that perpetuate their criminalization and instead develop policies to ensure support and access to prevention and treatment.  相似文献   
162.
The gut bacteria of eight tephritid species were isolated and characterized. Larvae of the genus Urophora and Tephritis dilacerata proved to house no microorganisms in their digestive organs. Bacteria were isolated from adults of five fruit fly species. Most of the bacterial strains were enterobacteria. Fruit-infesting tephritid species, flower-head species and gall formers had similar gut floras consisting of bacteria widespread in the soil and on the phylloplane.  相似文献   
163.
The geographical and bathymetric distribution of southern African octocorals is analysed. Of the over 200 estimated species of regional octocorals, 81 confirmed and adequately described species are studied using a radial sector method. Two primary faunal components are recognized–endemic (53.3% of the fauna by numbers of species) and Indo-Pacific (39.4%). An Atlantic component contributes only minimally (about 1.7%), while the remaining fauna is made up of cosmopolites (2.8%) and scattered species (2.8%). A subantarctic component is not evident for the present-day, although evidence for previous contact is presented. A sister-group analysis using genera as a guide to sister species, shows the biogeographic affinities for the present-day fauna as a whole to be 45% Indo-Pacific, 31% cosmopolitan, 10% endemic, 10% Atlantic and 4% southern oceans (subantarctic). Applying the same method to only those genera with endemic species shows the affinities of the present-day endemic fauna to be 27.5% Indo-Pacific, 27.5% endemic, 24% cosmopolitan, 14% Atlantic and 7% subantarctic. Clearly defined boundaries for west, south, and east coast faunas (as recognized by previous authors in describing various intertidal faunas) are found not be present with regard to the octocoral fauna (largely due to its overwhelmingly subtidal nature). Instead two primary zoogeographic provinces are recognized–the Cape Endemic Province (extending from Liideritz to Inhaca Island) and the south-western fringe of the Indo-Pacific Province from East London north-eastwards. An overlap zone between these two is recognized between East London and Inhaca Island, with the region in the vicinity of Richards Bay having an essentially evenly mixed fauna (roughly 50% Cape Endemic Province and 50% Indo-Pacific). Of the 84 octocoral genera recorded for the region, seven (or 8.3%) are endemic, and of these, five are monotypic while two are ditypic. The fauna is shown to be predominantly sublittoral (about 95% by numbers of species), the shallow sublittoral (< 100 m in depth) being the region with highest species richness. Pennatulaceans are eurybathic (intertidal to 4756 m) and clearly show a high proportion of cosmopolites (20% of presently identified species). Soft corals are stenobathic and restricted to the intertidal, continental shelf and uppermost portion of the continental slope (<500m), while gorgonians are intermediate in depth distributon (intertidal to 1200 m). No cosmopolitan alcyonaceans are presently recorded. The centre of the Cape Endemic Province is the Agulhas Bank–an extensive region of shallow continential shelf (< 200 m in depth) between Cape Town and East London. Two regions of octocoral radiation for southern Africa are postulated–the Agulhas Bank and the western Indian Ocean.  相似文献   
164.
Four German isolates (FS1, SR2, SAW1 and DEG2) of Bremia lactucae originating from lettuce cultivars with R‐factors R18 and Dm6 + R36 were used for detailed characterization of virulence factors (v‐factors) and for the study of the resistance efficiency in wild Lactuca spp. germplasm. The highest complexity of v‐phenotype was recognized in isolate DEG2, which overcomes resistance in cv. Mariska (R18) and line CS‐RL (L. serriola × L. sativa, R18 + ?), until now known as resistant to all known races of B. lactucae in Europe. However, some sparse sporulation also occurred on cv. Titan (Dm6 + R36). The isolates SR2 and SAW1 overcome the resistance based on the gene R36, but are avirulent to R18. The v‐phenotype of SR2 is highly complex with the most important v‐factors being present except for v14 and v18. The isolate FS1 is the first in Germany originating from a cultivar with R18 (cv. Samourai). The search for efficient sources of resistance in 64 accessions of 11 wild Lactuca spp. and primitive forms of L. sativa showed broad variation in accession–isolate interactions. Expression of race‐specific resistance in wild Lactuca spp. (L. serriola, L. viminea, L. virosa) was recorded frequently. Lactuca indica and L. saligna could be considered as the most efficient sources of resistance against isolates FS1, SR2 and SAW1. The isolate DEG2 showed the highest level of virulence. On seedlings of L. saligna, which is considered as a most important source of resistance against B. lactucae, there was frequently recorded limited sporulation, however this response cannot be considered as a susceptible. Except for some L. saligna accessions (CGN 05310 and CGN 05315), the resistance to all studied isolates was only observed in one accession of L. serriola (PI 253467).  相似文献   
165.
纯化鸡胚成纤维细胞培养的犬瘟热病毒(CanineDistemperVirus,CDV),获得病毒基因组RNA后,反转录合成双链病毒F基因cDNA。将此双链cDNA平端插入PUC19质粒SamⅠ位点构建重组质粒,进行cDNA克隆。以重组克隆质粒为模板PCR扩增,获得CDV全长F基因。将此F基因插入表达载体PBV220,在大肠杆菌中表达,通过对表达产物的最终鉴定,可确认所获片段为CDV全长F基因.  相似文献   
166.
Summary First divisions of embryogenic cells were studied in leaves of plantlets of aCichorium hybrid (C. intybus L. ×C. endivia L.) cultured in vitro in a liquid agitated medium, at 35 °C in the dark. Stages of reactivation of competent cells were characterized by increase of nucleus and nucleolus diameter, migration of the nucleus in the centre of the cell and thickening of the cell wall. The first division of reactivated embryogenic cells was symmetrical and anticlinal in regard to the xylem vessels orientation. Embryogenic structures consisted in I-type tetrads or in rows of 4–8 cells. Then the divisions occurred in thickness at one end, without polarization or formation of a suspensor-like structure.Abbreviations EC embryogenic cell - ES embryogenic structure  相似文献   
167.
Summary Rudist and stromatoporid associations of the Campanian from Central Oman are nearly monospecific. They are dominated byDurania aff.nicholasi, Vaccinites vesiculosus, Torreites milanovici or phaceloid and massive stromatoporids. Several other rudist genera play a secondary role. The thickness of the associations is rarely more than one metre. Solitary corals do not occur in the associations. Colonial corals are less common, although they are up to 1 m high and show considerable diversity. There are no binders. The reef structure indicates variable hydrodynamic conditions. They are always associated with very shallow water. The pureDurania aff.nicholasi patches with large colonial corals andTorreites milanovici are presumably the most rigid structures. The near monospecific associations ofVaccinites vesiculosus are widely distributed. Although mostly preserved in situ, strong currents, presumably caused by tropical storms, have repeatedly impaired and interrupted growth. The specific growth characteristics of the shell of some rudists, especially the radiolitids, enable an estimation of the individual lifespan. Frameworks of approximately 1 metre thickness probably developed in ±100 years. The sediments of the complete sections are predominantly bioclastic.  相似文献   
168.
Abstract: This study attempts to determine if projections ascending from the guinea pig cochlear nucleus (CN) could be glutamatergic and/or aspartatergic. Multiple radio frequency lesions were made to ablate the right CN. The ablation was verified histologically. To identify the principal targets of CN efferents, silver impregnation methods were used to localize the preterminal degeneration of fibers in transverse sections of the brainstem 5 and 7 days after CN ablation. CN efferents projected heavily to the lateral superior olive (LSO) ipsilaterally, the medial superior olive (MSO) bilaterally, and contralaterally to the medial (MNTB) and ventral (VNTB) nuclei of the trapezoid body, the ventral (VNLL) and intermediate nuclei of the lateral lemniscus and the central nucleus of the inferior colliculus (ICc). There were smaller projections to the lateral nucleus of the trapezoid body ipsilaterally, the dorsal and dorsomedial periolivary nuclei bilaterally, and the dorsal nucleus of the lateral lemniscus contralaterally. There were sparse projections to the VNLL and ICc ipsilaterally and the CN contralaterally, and a very sparse projection to the contralateral LSO. To determine if CN efferents were glutamatergic and/or aspartatergic, the fresh brainstem was sectioned transversely and samples of the LSO, MSO, MNTB, VNLL, and ICc were taken to measure the electrically evoked release and the uptake of d -[3H]Asp and [14C]Gly or [14C]GABA 3–5 days after the CN ablation. The release studies suggest that only certain of the histologically identified projections ascending from the CN may be glutamatergic and/or aspartatergic. CN ablation depressed d -[3H]Asp release in the MSO bilaterally and in the contralateral MNTB and VNLL, suggesting that the CN efferents to these nuclei may use glutamate or aspartate as a transmitter. It was unclear whether a marginal depression of d -[3H]Asp release in the ipsilateral LSO reflected the presence of glutamatergic CN projections to this nucleus. d -[3H]Asp release in the ICc was unaffected, suggesting that CN efferents to this nucleus may not be glutamatergic. There were no deficits in d -[3H]Asp uptake. [14C]Gly release from the LSO and MSO was unchanged. [14C]Gly uptake was unchanged in the MSO and depressed only in the contralateral LSO, possibly reflecting subnormal uptake activity in endings contributed by contralateral MNTB cells that had lost their CN efferents. [14C]GABA uptake in the MNTB, VNLL, and ICc was unchanged. [14C]GABA release was unchanged in the VNLL and ICc. [14C]GABA release was depressed only in the contralateral MNTB, possibly reflecting the loss of a small complement of GABAergic CN efferents and the reaction of GABAergic projections from the contralateral VNTB to their loss of CN efferents.  相似文献   
169.
170.
Epidermal topography was examined, including papillate ridges, grooves and ciliated sensory papillae of Craspedella sp. from the branchial chamber of redclaw crayfish, Cherax quadricarinatus, from Queensland, Australia. Rhandites were observed to discharge from ducts opening mainly in a small distal region of the ventral epidermis of the three central (of five) tentacles. These regions, devoid of ciliated sensory papillae, serve to adhere the anterior end of the worms during locomotion. Secretions from glands associated with the posterior attachment organ were observed to discharge from pores on the outside region of the ventral surface of the disc.A comparison of various scanning electron microscopy (SEM) fixation techniques showed that (1) hot fixatives at 90 °C provide most information on the largest number of epidermal structures and (2) different fixation regimes highlight different epidermal features.  相似文献   
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