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91.

Background  

Serum C-reactive protein (CRP) has been identified in prospective epidemiological research as an independent risk marker for cardiovascular disease. In this paper, short-term biological variation of CRP is documented and a strategy to test the reliability of a single CRP sample is proposed.  相似文献   
92.
The evolution of the inflorescence head in Asteraceae is important in the diversification of this largest angiosperm family. The aggregation of heads into higher-order capitulescences (secondary heads or syncephalia) is considered evolutionarily advanced. The genera Moscharia, Nassauvia, Polyachyrus, and Triptilion of the subtribe Nassauviinae (Mutisieae) have syncephalia with differing degrees of capitula condensation. ITS and plastid trnL-trnF regions were analyzed separately and together using maximum parsimony and maximum likelihood to examine the evolution of syncephalia in the Nassauviinae. The four genera displaying syncephalia do not form a clade minus taxa without syncephalia, indicating that secondary heads in Nassauviinae have either convergently evolved twice in the subtribe (or, very unlikely) once with multiple reversions. Strong support was obtained for a sister relationship between Leucheria (without syncephalium) and Polyachyrus, and both sister to Moscharia. Nassauvia and Triptilion form a distinct clade but are sister to other genera, Perezia and Panphalea, without syncephalium. Previous hypotheses postulated the evolution from simple to more complex secondary heads. We show that the ancestor of Moscharia, Polyachyrus, and Leucheria, in a more arid habitat, had a complex type of secondary head, and loss of complexity occurred in response to a shift from arid to mesic conditions.  相似文献   
93.

Background  

The genus Morus, known as mulberry, is a dioecious and cross-pollinating plant that is the sole food for the domesticated silkworm, Bombyx mori. Traditional methods using morphological traits for classification are largely unsuccessful in establishing the diversity and relationships among different mulberry species because of environmental influence on traits of interest. As a more robust alternative, PCR based marker assays including RAPD and ISSR were employed to study the genetic diversity and interrelationships among twelve domesticated and three wild mulberry species.  相似文献   
94.

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   
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97.
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   
98.
The restriction map of rDNA from South American camelids and the Bactrian camel was analyzed by digestion of high-molecular-weight DNA with endonucleases EcoRI, BamHI and the two combined followed by Southern blot hybridization with probes for the 18S and 28S rDNA sequences. We scored a total of 17 restriction sites, six of which were mapped conserved in all the species. The other eleven corresponded to spacer regions and revealed variations between these taxa. The study showed that the two groups differ in the length of the internal transcribed spacer. Also they showed the existence of two regions of fast evolution on the opposite termini of the external spacer. A restriction site present at low frequency in the non-transcribed spacer of guanaco and llama was the only difference encountered within the South American group.  相似文献   
99.
We previously reported that some cattle affected by bovine spongiform encephalopathy (BSE) showed distinct molecular features of the protease-resistant prion protein (PrPres) in Western blot, with a 1–2 kDa higher apparent molecular mass of the unglycosylated PrPres associated with labelling by antibodies against the 86–107 region of the bovine PrP protein (H-type BSE). By Western blot analyses of PrPres, we now showed that the essential features initially described in cattle were observed with a panel of different antibodies and were maintained after transmission of the disease in C57Bl/6 mice. In addition, antibodies against the C-terminal region of PrP revealed a second, more C-terminally cleaved, form of PrPres (PrPres #2), which, in unglycosylated form, migrated as a ≈ 14 kDa fragment. Furthermore, a PrPres fragment of ≈7 kDa, which was not labelled by C-terminus-specific antibodies and was thus presumed to be a product of cleavage at both N- and C-terminal sides of PrP protein, was also detected. Both PrPres #2 and ≈7 kDa PrPres were detected in cattle and in C57Bl/6 infected mice. These complex molecular features are reminiscent of findings reported in human prion diseases. This raises questions regarding the respective origins and pathogenic mechanisms in prion diseases of animals and humans.Key Words: prion, BSE, Creutzfeldt-Jakob, Gerstmann-Sträussler-Scheinker, Western blot, amyloid  相似文献   
100.

Background  

Tuberculosis (TB) is a major health problem and HIV is the major cause of the increase in TB. Sub-Saharan Africa is endemic for both TB and HIV infection. Determination of the prevalence of M. tuberculosis strains and their drug susceptibility is important for TB control.  相似文献   
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