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11.
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A. T. Fisk M. Holst K. A. Hobson J. Duffe J. Moisey R. J. Norstrom 《Archives of environmental contamination and toxicology》2002,42(1):118-126
To examine the influence of diet and age on organochlorine contaminant (OC) concentrations in two closely related ringed seal
(Phoca hispida) populations enantiomeric fractions (EFs) of chiral contaminants and stable isotopes of nitrogen (δ15N) and carbon (δ13C) were measured along with OCs in ringed seals collected from the east and west side of the Northwater Polynya. Seals from
these two locations were feeding at the same trophic level based on δ15N values in muscle but had slightly different sources of carbon based on δ13C measurements in muscle. After removing the influence of age, sex, and blubber thickness, OC concentrations did not vary
between ringed seals from the east and west side of the polynya. ΣPCB, ΣDDT, and Σchlordane were found to increase with age
for both male and female seals. The inclusion of older (>20 years) female seals, which may have a reduced reproductive effort,
may influence the relationships in females. Stable isotopes failed to describe OC concentrations in ringed seals suggesting
that diet was not a major factor in variation of OC concentrations within this ringed seal population. Cis- and trans-chlordane, oxychlordane, and heptachlor epoxide were all nonracemic in the ringed seal blubber but did not vary with age,
sex, or collection site. α-HCH appeared racemic (enantiomeric fraction = 0.50 ± 0.01) in the seals, although this EF is different
than those previously observed in their prey species, and was found to vary significantly with age. EF values in the ringed
seals varied considerably from other Arctic marine mammals and seabirds, providing addition evidence that the type(s) and
characteristic(s) of the enzymes involved in biotransformation of chiral OCs vary between these organisms.
Received: 11 April 2001/Accepted: 27 June 2001 相似文献
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CA Schroeter† L Kaas† JJ Waterval† PM Bos‡ HAM Neumann§ 《Journal of the European Academy of Dermatology and Venereology》2007,21(9):1170-1174
AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated. 相似文献
15.
JJ Piccininni 《The Journal of the Canadian Chiropractic Association》1994,38(4):223-226
This paper examines various devices used in strength building exercise programs. These include free weights, pulley machines, variable resistance weight machines, isokinetic units and elastic tubing and banding. Advantages and disadvantages of each are discussed and examined from the view point of the health care provider and the suitability of each type of device for prescribed progressive resistance exercise programs for patients. In addition to such practical aspects such as cost and maintenance, biomechanical factors, types of contraction elicited, ease of patient instruction and proprioception benefits are also compared in order to assist the clinician in selecting the most appropriate equipment for each individual patient. 相似文献
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Verschuren MC; Blom B; Bogers AJ; Spits H; van Dongen JJ 《International immunology》1998,10(12):1873-1880
Recombination of deltaRec to psiJalpha will delete the TCR delta gene,
which is thought to play an important role in the bifurcation of the TCR
alphabeta versus TCR gammadelta differentiation lineages. We recently
detected a DNA-binding protein in human thymocytes, the so- called PJA-BP,
which recognizes the psiJalpha gene segment and might be one of the factors
involved in the regulation of preferential deltaRec- psiJalpha
rearrangements. We now investigate PJA-BP expression and its correlation
with TCR delta gene deletion in thymocytes. Our electrophoretic mobility
shift assay experiments showed that the PJA-BP is evolutionary conserved in
human, murine and simian thymocytes. Using a large series of human
hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is
thymocyte specific and seems to be restricted to thymocytes committed to
the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte
subpopulations showed that preferential deltaRec-psiJalpha rearrangements
as well as PJA-BP expression can be detected from the immature
CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage
onwards. These experiments indicate that expression of PJA-BP in human
thymocytes starts simultaneously with preferential deltaRec-psiJalpha
rearrangements, which supports our hypothesis that PJA-BP is one of the
factors involved in the preferential recombination of deltaRec to
psiJalpha.
相似文献
20.
H. Galbo E. A. Richter J. J. Holst N. J. Christensen 《Pflügers Archiv : European journal of physiology》1977,369(1):21-25
Summary The significance of glucagon for post-exercise glucose homeostasis has been studied in rats fasted overnight. Immediately after exhaustive swimming either rabbit-antiglucagon serum or normal rabbit serum was injected by cardiac puncture. Cardiac blood and samples of liver and muscle tissue were collected before exercise and repeatedly during a 120 min recovery period after exercise. During the post-exercise period plasma glucagon concentrations decreased but remained above pre-exercise values in rats treated with normal serum, while rats treated with antiglucagon serum had excess antibody in plasma throughout. Nevertheless, all other parameters measured showed similar changes in the two groups. Thus after exercise the grossly diminished hepatic glycogen concentrations remained constant, while the decreased blood glucose concentrations were partially restored. Simultaneously concentrations in blood and serum of the main gluconeogenic substrates, lactate, pyruvate, alanine and glycerol declined markedly. During the post-exercise period NEFA concentrations in serum and plasma insulin concentrations remained increased and decreased, respectively, while plasma catecholamines did not differ from basal values. Muscle glycogen concentrations decreased slightly. These findings suggest that in the recovery period after exhaustive exercise the increased glucagon concentrations in plasma do not influence gluconeogenesis. 相似文献