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21.
K T Kray E N Squire W R Tipton J C Selner J O'Dea H S Nelson 《The Journal of allergy and clinical immunology》1985,76(4):623-627
A formulation of 2% cromolyn sodium (CS) ophthalmic solution without the preservative, 2-phenylethanol, was compared with placebo in 58 patients with seasonal allergic conjunctivitis. Selection was based on history and positive skin tests. Neither immunotherapy nor use of antihistamines was allowed. This study was double-blinded and stratified by RAST scores to assure comparable groups. Either CS or placebo was used six times daily. Patients were observed weekly for 5 weeks during the peak of the fall weed-pollen exposure. Nasal symptoms were treated as required with beclomethasone nasal spray, and uncontrolled ocular symptoms were treated with boric acid and ephedrine solution. Nasal and ocular symptoms were recorded. There was a significant suppression of eye symptoms in the group receiving CS ophthalmic solution (p less than 0.02) during weeks 2, 4, and 5. There was a trend for nasal symptoms and the requirement for nasal beclomethasone to be less in patients receiving CS. 相似文献
22.
J M Overton K C Kregel G Davis-Gorman D R Seals C M Tipton L A Fisher 《Physiology & behavior》1991,49(1):93-98
The purpose of this study was to test the hypothesis that the cardiovascular and sympathoadrenal responses to acute environmental stress are attenuated by exercise training. Furthermore, we tested the hypothesis that the cardiovascular and sympathoadrenal responses to intracerebroventricular (ICV) administration of corticotropin-releasing factor (CRF) would be attenuated by training. Conscious, unrestrained, male Sprague-Dawley rats assigned to either a treadmill trained (16-26 m/min, 30-60 min/day, 5 days/week) or nontrained (16-26 m/min, 10 min/day, 1 day/week) group were studied. After 8-10 weeks of training, maximal oxygen uptake was significantly higher in the trained (108 +/- 3 ml/kg/min) vs. the nontrained (94 +/- 4 ml/min/kg) group. There were no significant differences in baseline mean arterial pressure, heart rate and plasma catecholamine levels associated with training. Trained rats exhibited significantly attenuated elevations in arterial pressure (20 +/- 3 vs. 36 +/- 2 mmHg for nontrained) and heart rate (-3 +/- 3 vs. 12 +/- 5 beats/min for nontrained) in response to acute noise stress. Twenty minutes after ICV administration of CRF, blood pressure (trained = 119 +/- 2 mmHg, nontrained = 127 +/- 2 mmHg), heart rate (trained = 408 +/- 8 beats/min, nontrained = 424 +/- 10 beats/min), plasma norepinephrine levels (trained = 757 +/- 54 pg/ml, nontrained = 775 +/- 100 pg/ml) and plasma epinephrine levels (trained = 266 +/- 29 pg/ml, nontrained = 225 +/- 42 pg/ml) were significantly elevated in both trained and nontrained groups. CRF-induced elevations of blood pressure, but not heart rate or plasma catecholamine levels, were significantly attenuated in the trained group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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24.
Kacin A Golja P Eiken O Tipton MJ Gorjanc J Mekjavic IB 《European journal of applied physiology》2005,95(2-3):213-220
The effect of graded ischaemia in the legs on the regulation of body temperature during steady-state exercise was investigated in seven healthy males. It was hypothesised that graded ischaemia in the working muscles increases heat storage within the muscles, which in turn potentiates sweat secretion during exercise. Blood perfusion in the working muscles was reduced by applying a supra-atmospheric pressure (+6.6 kPa) around the legs, which reduced maximal working capacity by 29%. Each subject conducted three separate test trials comprising 30 min of steady-state cycling in a supine position. Exercise with unrestricted blood flow (Control trial) was compared to ischaemic exercise conducted at an identical relative work rate (Relative trial), as well as at an identical absolute work rate (Absolute trial); the latter corresponding to a 20% increase in relative workload. The average (SD) increases in both the rectal and oesophageal temperatures during steady-state cycling was 0.3 (0.2)°C and did not significantly differ between the three trials. The increase in muscle temperature was similar in the Control (2.7 (0.3)°C) and Absolute (2.4 (0.7)°C) trials, but was substantially lower (P<0.01) in the Relative trial (1.4 (0.8)°C). Ischaemia potentiated (P<0.01) sweating on the forehead in the Absolute trial (24.2 (7.3) g m–2 min–1) compared to the Control trial (13.4 (6.2) g m–2 min–1), concomitant with an attenuated (P<0.05) vasodilatation in the skin during exercise. It is concluded that graded ischaemia in working muscles potentiates the exercise sweating response and attenuates vasodilatation in the skin initiated by increased core temperature, effects which may be attributed to an augmented muscle metaboreflex. 相似文献
25.
Zelinski-Wooten MB; Slayden OD; Chwalisz K; Hess DL; Brenner RM; Stouffer RL 《Human reproduction (Oxford, England)》1998,13(2):259-267
Large doses of antiprogestin typically disrupt menstrual cyclicity. A
chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which
permits continued menstrual cyclicity but alters gonadal- reproductive
tract activity, was established. Rhesus monkeys received vehicle (n = 6) or
0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight
daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and
gonadotrophin profiles were normal during cycles involving vehicle and 0.01
and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle
oestradiol and gonadotrophin surges, and subsequent progesterone
production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied
by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half
the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group
were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of
C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and
cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily
treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in
macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed
ovarian cyclicity, menstruation was disrupted in some animals. Increasing
the dose to 0.1 mg/kg antagonized pituitary function and resulted in
anovulation and amenorrhoea. A chronic low-dose regimen of the
antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity,
has potential as a contraceptive in women.
相似文献
26.
We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed using pain scores and the amount of supplementary analgesia required. The results demonstrate no benefit in delay in tourniquet deflation. 相似文献
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28.
The use of specialized coils to improve signal-to-noise ratios in magnetic resonance (MR) imaging is an important innovation. The role of surface coils has not yet been well defined, but it seems likely that they will be routinely used for clinical imaging of the orbit, neck, and spine. Surface coils have important limitations that make other designs, such as "closely coupled" volume coils, attractive for some applications, especially for limb imaging. With improvement in our ability to visualize anatomy with MR imaging, specialized radio frequency coils may provide new imaging capabilities for clinical problems that were not previously considered to be indications for diagnostic imaging. 相似文献
29.
Tony Wawina-Bokalanga Bert Vanmechelen Valentine Lhermitte Joan Martí-Carreras Valentijn Vergote Fara Raymond Koundouno Joseph Akoi-Bor Ruth Thom Tom Tipton Kimberley Steeds Kita Balla Moussa Ablam Amento Lies Laenen Sophie Duraffour Martin Gabriel Paula Ruibal Yper Hall Mandy Kader-Kond Stephan Günther Guy Baele Cesar Muoz-Fontela Johan Van Weyenbergh Miles W. Carroll Piet Maes 《Emerging infectious diseases》2021,27(1):76
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD. 相似文献
30.
Lars L Andersen Sannie V Thorsen Mona Larsen Emil Sundstrup Ccile RL Boot Reiner Rugulies 《Scandinavian journal of work, environment & health》2021,47(1):15
Objectives:The demographic changes in Europe underline the need for an extension of working lives. This study investigates the importance of physical work demands and psychosocial work factors for working beyond the state pension age (65 years).Methods:We combined data from three cohorts of the general working population in Denmark (DWECS 2005 and 2010, and DANES 2008), where actively employed workers aged 55–59 years replied to questionnaires about work environment and were followed until the age of 66 years in the Danish AMRun register of paid employment. Using logistic regression analyses, we calculated prevalence ratios (PR) and 95% confidence intervals (CI) for the association between physical and psychosocial work factors and working beyond state pension age, adjusted for age, sex, cohort, cohabiting, sector, income, vocational education, working hours, lifestyle, and previous sickness absence.Results:Of the 2884 workers aged 55–59 years, 1023 (35.5%) worked beyond the state pension age. Higher physical work demands was associated with a lower likelihood (PR 0.69, 95% CI 0.58–0.82) and a good psychosocial work environment was associated with higher likelihood (average of 7 items: PR 1.81, 95% CI 1.49–2.20) of working beyond state pension age. Stratified analyses did not change the overall pattern, ie, a good overall psychosocial work environment – as well as several specific psychosocial factors – increased the likelihood of working beyond state pension age, both for those with physically active and seated work.Conclusion:While high physical work demands was a barrier, a good psychosocial work environment seems to facilitate working beyond state pension age, also for those with physically active work. 相似文献