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71.
72.
This article will contextualize ethnographic and clinicalfeatures that distinguish one particular alternativehealing method (Self-Acceptance Training) frommainstreampsychotherapeutic procedures. Factors common to manypsychotherapies are listed and a series of contrasts andcomparisons made by examining definitions of: (1) presentingproblems, (2) inciting events, (3) phasic development, (4)taxonomic classifications, (5) therapeutic interventions,and (6) prognostic formulations. The alternative method oftreatment described in a companion publication(SAT) is used to makesome specific comparisons (Zatzick and Johnson 1997).Baschs (1980) concise recording of a dynamic therapy isborrowed for purposes of a comparative hypothetical treatmentof his patient through a Self-Acceptance Training session.Some directions for future work are suggested.  相似文献   
73.
SYNOPSIS. Cryoprotectants were tested in both complex and semidefined media for the trypanosomatid Crithidia fasciculata. Near log-phase or end-of-log-phase cultures were frozen for 24–48 hr at ∼ -20 C, then warmed in air to room temperature. Immediate motility was correlated with viability. The best protectant of the 83 tested was glycerol at ∼ 10% (w/v). Survival without cryoprotectant was rare. Outstanding cryoprotectants (perhaps also useful solvents for drugs poorly soluble in water) were: ethylene glycol; 2,2'-dioxyethanol (diethylene glycol); 1,2,4-butanetriol; 1,4-cyclohexanediol; dimethylsulfoxide; propylene glycol; and N -acetylethanolamine. Several sugars were active, e.g., D-arabinose, sucrose, and sorbitol. Trypanosomes tolerated cryoprotectants much less; tolerance was better in growth media than in suspension media. Trypanosoma gambiense was grown in blood-enriched media + 2-2.5% glycerol, suspended in 20% (w/v) glycerol. then frozen; this permitted 3-week survival. T. conorhini survived 4 weeks after growth in media containing glycerol 2.5%+ ethylene glycol 4%+ rutin 1.0 mg per 100 ml.  相似文献   
74.
Mesenchymal stromal cell (MSC) therapies have been pursued for a broad spectrum of indications but mixed reports on clinical efficacy have given rise to some degree of skepticism regarding the effectiveness of this approach. However, recent reports of successful clinical outcomes and regulatory approvals for graft-versus-host disease, Crohn's disease and critical limb ischemia have prompted a shift in this perspective. With hundreds of clinical trials involving MSCs currently underway and an increasing demand for large-scale manufacturing protocols, there is a critical need to develop standards that can be applied to processing methods and to establish consensus assays for both MSC processing control and MSC product release. Reference materials and validated, uniformly applied tests for quality control of MSC products are needed. Here, we review recent developments in MSC manufacturing technologies, release testing and potency assays. We conclude that, although MSCs hold considerable promise clinically, economies of scale have yet to be achieved although numerous bioreactor technologies for scalable production of MSCs exist. Additionally, rigorous disease-specific product testing and comprehensive understanding of mechanisms of action, which are linked to relevant process and product release potency assays, will be required to ensure that these therapies continue to be successful.  相似文献   
75.
In a recent study, Avise & Liu (2011) (Biological Journal of the Linnean Society 102: 707–714) presented evidence indicating that Linnean ranks are not temporally standardized (i.e. taxa of the same rank differ greatly in age). This is one more argument that ranks veil rather than convey biological comparability. The authors also discuss recent suggestions as to how these shortcomings should be overcome, in particular temporal banding (by which the same rank is assigned to taxa of the same geological age) and time‐clipping (adding a code to each taxon denoting the geological episode when it originated). In this short comment, it is argued that both temporal banding and time‐clipping may be deleterious in taxonomic practice and that the abandonment of the Linnean ranks is long overdue. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 732–734.  相似文献   
76.
77.
Charles Darwin's historic visit to the Galápagos Islands in 1835 represents a landmark in the annals of science. But contrary to the legend long surrounding Darwin's famous Galápagos visit, he continued to believe that species were immutable for nearly a year and a half after leaving these islands. This delay in Darwin's evolutionary appreciation of the Galápagos evidence is largely owing to numerous misconceptions that he entertained about the islands, and their unique organic inhabitants, during the Beagle voyage. For example, Darwin mistakenly thought that the Galápagos tortoise–adult specimens of which he did not collect for scientific purposes–was not native to these islands. Hence he apparently interpreted reports of island-to-island differences among the tortoises as analogous to changes that are commonly undergone by species removed from their natural habitats. As for Darwin's finches, Darwin initially failed to recognize the closely related nature of the group, mistaking certain species for the forms that they appear, through adaptive radiation, to mimic. Moreover, what locality information he later published for his Galápagos finch specimens was derived almost entirely from the collections of three other Beagle shipmates, following his return to England. Even after he became an evolutionist, in March of 1837 (when he discussed his Galápagos birds with the eminent ornithologist John Gould), Darwin's theoretical understanding of evolution in the Galápagos continued to undergo significant developments for almost as many years as it took him to publish the Origin of Species (1859). The Darwin-Galápagos legend, with its romantic portrait of Darwin's 'eureka-like' insight into the Galápagos as a microcosmic 'laboratory of evolution', masks the complex nature of scientific discovery, and, thereby, the real nature of Darwin's genius.  相似文献   
78.
Many tropical ant-plants provide specialized ant partners with food, which may attract foreign ants parasitizing the mutualism. We present evidence for the ant-plant genus Macaranga , showing that ant competition has forced host plants to hide food resources and restrict access to the mutualists. In Macaranga myrmecophytes, the influence of ant competition strongly depends on the presence of slippery 'wax barriers'. Of all Macaranga ant-plant species, 50% have waxy stems that can be climbed only by the specific ant partners and not by other ant species. We compared the presentation of food (food bodies and extrafloral nectar) between waxy and non-waxy Macaranga host plants using traditional and phylogenetic comparative methods. Consistent with the hypothesized effect of ant competition, wax-free Macaranga host species had fewer extrafloral nectaries and more often produced food bodies under recurved or tubular stipules inaccessible to other ants; closed stipules were less persistent in waxy hosts. Several traits showed phylogenetic signal, but our finding of a more promiscuous food presentation in waxy Macaranga hosts was still supported by phylogenetic comparative analyses. We conclude that competition among ants is an important factor in the evolution of myrmecophytism, and that it has given rise to traits acting as protective filter mechanisms.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 177–193.  相似文献   
79.
FISHER, J. B. & EWERS, F. W., 1992. Xylem pathways in liana stems with variant secondary growth. The three-dimensional construction of stem xylem in tropical lianas (woody vines) was studied using several approaches: 1. observations of the xylem surface in stems with bark removed after NaOH treatment or natural retting; 2. reconstructions from serial transverse sections; 3. movement of dye solutions up isolated xylem sectors in intact plants, and 4. flow of dye solutions down branches and xylem sectors in isolated stem segments. Long distance (up to several metres) xylem pathways in unbranched stems and connections between lateral branches and main stems are described for !5 species in eight families which represented seven differnt patterns of secondary growth. The xylem in even the most complex stems is integrated by three-dimensional interconnections of xylem regions which may appear isolated in transverse section. Interconnections are most common at leaf and branch nodes. Some old stems have peripheral xylem that remains isolated over long distances in unbranched stems, but even these had structural and physiological interconnections between xylem regions at branch nodes.  相似文献   
80.
Ribulose, 1,5-bisphosphate carboxylase has been isolated from leaves of glanded cotton, (Gossypium hirsutum L. cv. TM1), by techniques described. A yield exceeding 4.5 mg enzyme per gram leaf tissue has been obtained by utilizing a sodium homogenizing buffer without the addition of any reducing agent. Sodium dodecylsulfate gel electrophoresis of the enzyme shows the fraction to be relatively free of contaminants. Enzymic assays of the isolate give a specific activity of 1.1 μmol CO2 fixed (min-mg protein)?1 at 30°C.  相似文献   
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