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51.
The objective was to evaluate a postal questionnaire screening procedure for selection of subjects with positive reactions to skin prick tests with common allergens. The project consisted of a screening, with subsequent skin prick test of two selected groups. The setting was the Glostrup Population Studies institute in Copenhagen, Denmark. Participants in the screening included 8000 subjects, aged 15–69 years. The subjects were randomly selected from the population of western Copenhagen County, Denmark. From the 6998 respondents (87.5%), 793 subjects were randomly selected (Random Group), and 788 subjects were chosen on the basis of their answers to the questionnaire (Symptom Group). Both groups were invited to take skin prick tests. Attendance rates were 75.5% (Random Group) and 80.6% (Symptom Group).
The main outcome measures were responses (yes or no) to the specific questions and the subjects' skin reaction (positive or negative). The association between symptoms and skin reactivity, adjusted for the effects of sex and age, was summarized by odds ratios. Symptoms on exposure to allergens were highly associated with positive skin reactivity. In the Symptom Group the percentage of subjects with at least one positive skin reaction was 57.7%, which was twice as much (28.4%) as in the Random Group. The results show that it was possible to select a group with high skin reactivity on the basis of the symptoms reported in the screening. Questions about exposure to allergens were the most appropriate for selection of this group. 相似文献
The main outcome measures were responses (yes or no) to the specific questions and the subjects' skin reaction (positive or negative). The association between symptoms and skin reactivity, adjusted for the effects of sex and age, was summarized by odds ratios. Symptoms on exposure to allergens were highly associated with positive skin reactivity. In the Symptom Group the percentage of subjects with at least one positive skin reaction was 57.7%, which was twice as much (28.4%) as in the Random Group. The results show that it was possible to select a group with high skin reactivity on the basis of the symptoms reported in the screening. Questions about exposure to allergens were the most appropriate for selection of this group. 相似文献
52.
Arrested neuronal proliferation and impaired hippocampal function following fractionated brain irradiation in the adult rat 总被引:11,自引:0,他引:11
The generation of new neurons in the adult mammalian brain has been documented in numerous recent reports. Studies undertaken so far indicate that adult hippocampal neurogenesis is related in a number of ways to hippocampal function.Here, we report that subjecting adult rats to fractionated brain irradiation blocked the formation of new neurons in the dentate gyrus of the hippocampus. At different time points after the termination of the irradiation procedure, the animals were tested in two tests of short-term memory that differ with respect to their dependence on hippocampal function. Eight and 21 days after irradiation, the animals with blocked neurogenesis performed poorer than controls in a hippocampus-dependent place-recognition task, indicating that the presence of newly generated neurons may be necessary for the normal function of this brain area. The animals were never impaired in a hippocampus-independent object-recognition task. These results are in line with other reports documenting the functional significance of newly generated neurons in this region. As our irradiation procedure models prophylactic cranial irradiation used in the treatment of different cancers, we suggest that blocked neurogenesis contributes to the reported deleterious side effects of this treatment, consisting of memory impairment, dysphoria and lethargy. 相似文献
53.
Murray Thomson Eng Cheng Chan Joanne Davies John Falconer Gemma Madsen Simon Geraghty Roger Smith 《Neuroscience letters》1990,110(3):343-348
It is not certain which protein kinase (A, C or both) is involved in the acute phase of β-endorphin (β-EP) release stimulated in the corticotrope by vasopressin (VP) and corticotropin-releasing factor (CRF). We have employed an isolated ovine anterior pituitary cell superfusion system to determine the dynamic effects of forskolin, a protein kinase A (PKA) stimulator, and phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator. Both secretagogues stimulated β-EP release within 5 min and therefore both PKA and PKC are potential mediators of the acute phase of hormonal stimulation of the corticotrope. Pretreatment with PMA specifically desensitized the pituitary cell columns to subsequent PMA exposure while not significantly altering sensitivity to forskolin or 50 mM KCl. 相似文献
54.
An enzyme-based in situ hybridisation method for the identification of Streptococcus suis 总被引:2,自引:0,他引:2
Madsen LW Boye M Jensen HE 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2001,109(10):665-669
A method for enzyme-based in situ hybridisation of Streptococcus suis was developed. It enables the light microscopic localization of bacterial ribosomal RNA (rRNA) in formalin-fixed paraffin-embedded tissues. A unique sequence in the 16S rRNA of S. suis was targeted. Different pretreatment protocols were applied to facilitate probe penetration and multiple detection systems were tested. The results were compared to those obtained by immunohistochemistry. Pretreatment was necessary to obtain a signal by in situ hybridisation. The use of proteinase-K pretreatment was optimal regarding sensitivity and preservation of tissue morphology. A strong specific in situ hybridisation signal was achieved in tissue sections containing S. suis in microcolonies and the microanatomy of the surrounding tissue was easily assessed. However, the signal distribution differed from that found immunohistochemically and low-grade infection could not be detected by in situ hybridisation. These findings were interpreted as reflecting the physiological state of the bacteria. Thus, this method could prove useful in future studies of the infection pathogenesis. 相似文献
55.
56.
The HLA-D/DR region in man encodes major determinants which stimulate T lymphocytes to proliferation. The genetic organization of this region is apparently complex and is at present largely unknown. One obstacle is the scarcity and quality of available typing reagents. In an attempt to obtain high quality anti-DR sera, a series of active immunizations was performed between highly selected, healthy unrelated donors and recipients.
One recipient (AR8) was immunized using cells incompatible for HLA-A2, B40 (w60), Cw3 and DIDRw6 and readily developed anti-A2 and B40 antibodies but no anti-C, DR, or other antibodies. When tested against his HLA genotypically fully identical brother using the cellular MLC, PLT, or CML techniques before immunization, results were mutually negative as expected. Following immunization, however, AR8 was able to mount MLC, PLT, and possibly CML responses against lymphocytes from the brother while the reverse combinations remained negative. When tested in the family the trait(s) thus identified seems to be maternally inherited.
These results suggest the existence of minor histocompatibility determinants encoded from regions not closely linked to HLA. The brother of AR8 and the immunizing donor thus seem to share one or more determinants not possessed by AR8. 相似文献
One recipient (AR8) was immunized using cells incompatible for HLA-A2, B40 (w60), Cw3 and DIDRw6 and readily developed anti-A2 and B40 antibodies but no anti-C, DR, or other antibodies. When tested against his HLA genotypically fully identical brother using the cellular MLC, PLT, or CML techniques before immunization, results were mutually negative as expected. Following immunization, however, AR8 was able to mount MLC, PLT, and possibly CML responses against lymphocytes from the brother while the reverse combinations remained negative. When tested in the family the trait(s) thus identified seems to be maternally inherited.
These results suggest the existence of minor histocompatibility determinants encoded from regions not closely linked to HLA. The brother of AR8 and the immunizing donor thus seem to share one or more determinants not possessed by AR8. 相似文献
57.
J Olbrecht O Madsen A Mader H Liesen W Hollmann 《International journal of sports medicine》1985,6(2):74-77
The present study examined the relationship between lactic acid concentration in capillary blood and swimming velocity during 11 typical endurance exercises (continuous swimming for 30 and 60 min, interval swimming with distances between 50 and 400 m, and with rest periods of 10 and 30 s) and during the "two-speed test" recently described by Mader. It was expected that a better understanding of these relationships could provide evidence how to adjust training intensities from results obtained during the two-speed test. Fifty-nine male swimmers of the German national level participated in this study. After a 30-min maximal swimming test, a mean lactic acid concentration of 4.01 +/- 0.75 mmol/l was found. The corresponding mean velocity was similar to the speed (V4) calculated for the 4 mmol/l level on the basis of the results obtained during the two-speed test (2 X 400). During 30 min continuous swimming at 95% to 105% of the velocity V4, there was a significant correlation (r = 0.82, P less than 0.001) between the swimming speed and the lactic acid concentration. In the 30-min maximal test, the velocity V4 correlated significantly with both the lactic acid concentration (r = -0.58, P less than 0.005) and the swimming speed (r = 0.97, P less than 0.001). During the interval exercises with rest periods of 10 s, the swimming velocities corresponding to the same lactic acid level as during continuous swimming, increased for the 50, 100, 200, and 400 m by 11.23%, 4.21%, 2.95%, and 2.02% of V4, respectively. With rest periods of 30 s, the swimming velocity for the 100, 200, and 400 m increased by 7.34%, 4.22%, and 3.01% of V4, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
Biomechanical and biochemical studies of tendon healing after conservative and surgical treatment 总被引:1,自引:0,他引:1
C. A. Carlstedt K. Madsen T. Wredmark 《Archives of orthopaedic and trauma surgery》1986,105(4):211-215
Summary Based on clinical studies, it has been proposed that conservative treatment of Achilles tendon ruptures is feasible. However, no biomechanical or biochemical confirmation of this proposal has been presented. In the present investigation the biomechanical and biochemical properties of tendons treated surgically and conservatively after transverse tenotomy were studied. Sixty-eight New Zealand White rabbits were used. A transverse tenotomy of the plantaris longus tendon of the left hind leg was performed. In half of the animals the tenotomy was repaired with a criss-cross silk suture and the limb was immobilized; the other half were treated with immobilization alone. The immobilization was maintained for 4 weeks with a long-leg plastic splint in both groups. After 4, 8, and 16 weeks the tendons were examined regarding biomechanical and biochemical parameters. There were no detectable differences in biomechanical parameters or in tendon elongation between the groups, nor was there any difference in the total hydroxyproline content, the amount of mature and of immature collagen, or the water content. The present findings are compatible with previous favorable reports on conservative treatment of Achilles tendon ruptures and thus suggest interesting clinical possibilities.
Zusammenfassung Aufgrund klinischer Beobachtungen ist die Auffassung vertreten worden, daß die konservative Behandlung der Achillessehnenruptur vorteilhaft ist. Jedoch fehlt es an biomechanischen und biochemischen Nachweisen dafür. In der vorliegenden Studie wurden die biomechanischen und biochemischen Eigenschaften von Achillessehnen nach einer queren Tenotomie, die entweder genäht oder konservativ behandelt wurde, untersucht. Achtundsechzig New-Zealand-White-Kaninchen bekamen eine quere Tenotomie an der Sehne des M. plantaris longus am linken Hinterbein. Die Tenotomie wurde dann in der Halfte der Falle mit einer criss-cross-Naht (Seide) repariert und das Bein ruhiggestellt, während die andere Hälfte der Versuchstiere nur mit Ruhigstellung behandelt wurde. Die Ruhigstellung des Beines erfolgte vier Wochen lang in einem die ganze Extremität umfassenden Verband aus Hexalite. Nach vier, acht und 16 Wochen wurde die Sehne auf ihre biomechanischen und biochemischen Eigenschaften untersucht. Wir sahen keinen Unterschied in den biomechanischen Eigenschaften oder in beobachteten Sehnenverlängerungen in den beiden Gruppen. Auch der Gesamtgehalt an Hydroxyprolin, der Anteil von reifem und unreifem Kollagen und der Wassergehalt waren ohne Unterschied. Die Ergebnisse dieser Untersuchung stimmen überein mit früheren Berichten über die Vorteile der konservativen Behandlung bei der Achillessehnenruptur und sind klinisch bedeutungsvoll.相似文献
59.
Madsen Christina Merete Tvede Bisgaard Sara Kjær Primdahl Jette Christensen Jeanette Reffstrup von Bülow Cecilie 《Journal of occupational rehabilitation》2021,31(4):866-885
Journal of Occupational Rehabilitation - Purpose To present an overview of the evidence of the effect of job loss prevention interventions, aiming to improve work ability and decrease absenteeism... 相似文献
60.
Aravind Krishnan Joshua Hsu Jinny S. Ha Stephen R. Broderick Pali D. Shah Robert SD. Higgins Christian A. Merlo Errol L. Bush 《American journal of surgery》2021,221(4):731-736
PurposeWe aimed to assess the prognostic value of Neutrophil to Lymphocyte Ratio (NLR) on long-term outcomes and graft dysfunction after lung transplantation.MethodsWe retrospectively reviewed all patients receiving a lung transplant at our institution from 2011 to 2014. The primary exposure was elevated NLR at the time of transplant, defined by NLR>4. The primary outcomes were graft failure and three-year all-cause mortality. Multivariate logistic regression and Kaplan-Meier survival analysis were used to analyze outcomes.Results95 patients were included. 40 patients (42%) had an elevated NLR. Elevated NLR was associated with graft failure (OR: 4.7 [1.2–18.8], p = 0.02), and three-year mortality (OR: 5.4 [1.3–23.2], p = 0.03) on multivariate logistic regression. Patients with elevated NLR demonstrated significantly lower survival on Kaplan-Meier analysis (50% versus 74%, p = 0.02). The c-statistic for our multivariate model was 0.91.ConclusionElevated neutrophil to lymphocyte ratio is associated with poor long-term survival and graft failure after lung transplantation. 相似文献