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81.
KATHRYN J. JEFFERY KATE A. ABERNETHY CAROLINE E. G. TUTIN MICHAEL W. BRUFORD 《Biological journal of the Linnean Society. Linnean Society of London》2007,91(2):281-294
Naturally shed hairs are an important source of genetic material for both conservation and forensics but are notoriously poor sources of DNA. DNA degradation in hair roots is caused by apoptosis as part of the cycle of hair growth and by autolysis in decomposing animals. Shed hairs are additionally exposed to degenerative environmental processes. However, genetic studies rarely examine hair root morphologies or refer to root growth phases prior to analysis, and detailed knowledge of the rapidity of DNA degradation amongst shed hairs is lacking. We examined the effects of biological and environmental processes on western lowland gorilla ( Gorilla gorilla gorilla Savage and Wyman) hair roots with respect to morphological characteristics and polymerase chain reaction (PCR) success at eight nuclear loci. Root type frequencies indicate that gorilla body hairs may exhibit a longer telogen phase than human head hairs. All plucked hair root types amplified more efficiently than shed hairs, and only 41% of shed hairs had root types considered suitable for genotyping. Telogen hairs from fresh nests were four-fold more useful for genotyping if the roots were associated with translucent epithelial tissue, and preselection of these root types doubled the overall data-yield to 58%. Nest age correlated with root morphology and PCR success, and PCR success was almost halved after 3 days of exposure. Finally, an association between postmortem interval, root morphology, and PCR success was observed that was consistent with postmortem changes reported in human head hairs. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 281–294. 相似文献
82.
Cees GM Kallenberg Arjan Vissink Frans GM Kroese Wayel H Abdulahad Hendrika Bootsma 《Arthritis research & therapy》2011,13(1):205
In vitro and in vivo experimental data have pointed to new immunopathogenic mechanisms in primary Sj?gren's syndrome (pSS). The availability of
targeted treatment modalities has opened new ways to selectively target these mechanistic pathways in vivo. This has taught us that the role of proinflammatory cytokines, in particular TNFα, is not crucial in the immunopathogenesis
of pSS. B cells appear to play a major role, as depletion of B cells leads to restoration of salivary flow and is efficacious
for treatment of extraglandular manifestations and mucosa-associated lymphoid tissue lymphoma. B cells also orchestrate T-cell
infiltration and ductal epithelial dearrangement in the salivary glands. Gene profiling of salivary gland tissue in relation
to B-cell depletion confirms that the axis of IFNα, B-cell activating factor, B-cell activation, proliferation and survival
constitutes a major pathogenic route in pSS. 相似文献
83.
In anti-neutrophil cytoplasmic autoantibody-associated vasculitides (AAV), several observations support a key role of T-helper
cells (CD4+ T cells) in disease pathophysiology. An expanded population of effector memory CD4+ T cells in AAV patients may contribute to tissue injury and disease progression. In addition, functional impairment of regulatory
T cells (TRegs) is reported in AAV patients. A fraction of TRegs have the capacity to differentiate into Th17 cells in the context of a proinflammatory environment. Therefore, nonfunctionality
of TRegs described in AAV patients may be caused by their conversion into IL-17-producing cells that may contribute to granulomatous
vasculitis. Further investigations directed at the plasticity of TRegs in AAV patients are warranted. 相似文献
84.
JEFFERY R. BROWN CHRISTINE A. BISHOP RONALD J. BROOKS 《The Journal of wildlife management》2009,73(3):419-425
ABSTRACT Short-distance translocation (SDT) is commonly used to mitigate snake-human interactions, yet little is known about its effectiveness or its effects on behavior and welfare of snakes. Between April 2004 and October 2005, we evaluated SDT as a conservation and management tool by investigating how 500-m SDT affected spatial ecology, body condition, and behavior of western rattlesnakes (Crotalus oreganus) surgically implanted with radiotransmitters in a field study near Osoyoos, British Columbia, Canada. Of 14 rattlesnakes subjected to SDT, 12 (85.7%) returned on ≥1 occasion (range 1–7 times) to the general area they were removed from. Rattlesnakes that underwent SDT showed an increase in total distance moved over an active season compared to non-translocated snakes, but there was no evidence to suggest SDT had an effect on activity range size. There was no evidence to suggest SDT affected body condition, behavior, or mortality rates. Short-distance translocation to high-quality undisturbed habitats was unsuccessful as a long-term solution to snake-human conflict because most translocated snakes returned to conflict areas within a short time (x̄x = 19.9 ± 8.7 days). However, SDT may be an effective short-term tool to manage snake-human conflict in areas where human presence is seasonal or short-lived if careful attention is paid to species-specific biological needs, habitat quality at the release site, and the location of the release site in relation to conflict areas. 相似文献
85.
Comparisons of epidemics of light leafspot of differing duration and time of initiation were made in two experiments using a single cultivar of Brassica napus. Fungicide was applied before introduction of disease to prevent infection or some time after inoculation to stop further disease development. In the first experiment, substantial reductions in green leaf area and total plant dry-matter were found at flowering when disease was introduced in the autumn or in January. Plant dry weight at maturity was also greatly reduced in these treatments. The detrimental effect of an epidemic initiated in the autumn was avoided to a large extent if fungicide application began in February. Epidemics initiated in March had only small effects on final dry-matter yield. Seed yield was negatively correlated with the length of the epidemic. In a second experiment, early epidemics initiated in the autumn were halted after different time intervals. Commencing fungicide application even as early as December failed to prevent some loss of dry weight at flowering. At maturity, however, dry weight and seed yield were reduced significantly when fungicide application was delayed until February. Failure to control the disease resulted in a 46% loss of seed yield. 相似文献
86.
87.
Structural complexes in the squid giant axon membrane sensitive to ionic concentrations and cardiac glycosides 下载免费PDF全文
Giant nerve fibers of squid Sepioteuthis sepioidea were incubated for 10 min in artificial sea water (ASW) under control conditions, in the absence of various ions, and in the presence of cardiac glycosides. The nerve fibers were fixed in OsO4 and embedded in Epon, and structural complexes along the axolemma were studied. 相似文献
88.
JEFFERY A. SHORT LILLIAN F. MAYBERRY JOHN R. BRISTOL 《The Journal of eukaryotic microbiology》1980,27(4):361-364
SYNOPSIS. Dipodomys merriami Mearns and Dipodomys ordi Woodhouse were surveyed for coccidia in El Paso County, Texas. Infections with Eimeria chobotari. Eimeria dipodomysis and Eimeria balphae were 24.8%. 4.4%, and 11%, respectively, for D. ordi. Dipodomys merriami had an infection level of 23.8% with E. chobotari . Four animals concurrently harbored E. chobotari and E. balphae or E. dipodomysis or a new species Eimeria chihuahuaensis. Male and female host infection levels were not significantly different. The new species is described and photographs of 3 previously described Eimeria from Dipodomys are presented. 相似文献
89.
Gert Kwakkel Carel GM Meskers Erwin E van Wegen Guus J Lankhorst Alexander CH Geurts Annet A van Kuijk Eline Lindeman Anne Visser-Meily Erwin de Vlugt J Hans Arendzen 《BMC neurology》2008,8(1):49
Background
Main claims of the literature are that functional recovery of the paretic upper limb is mainly defined within the first month post stroke and that rehabilitation services should preferably be applied intensively and in a task-oriented way within this particular time window. EXplaining PLastICITy after stroke (acronym EXPLICIT-stroke) aims to explore the underlying mechanisms of post stroke upper limb recovery. Two randomized single blinded trials form the core of the programme, investigating the effects of early modified Constraint-Induced Movement Therapy (modified CIMT) and EMG-triggered Neuro-Muscular Stimulation (EMG-NMS) in patients with respectively a favourable or poor probability for recovery of dexterity. 相似文献90.
Arvind K Awasthi GM Nagaraja GV Naik Sriramana Kanginakudru K Thangavelu Javaregowda Nagaraju 《BMC genetics》2004,5(1):1