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1.
IH Bjerkli R Myklebust S R?is?nen S Telimaa LE Stenfors 《Canadian Metallurgical Quarterly》1996,36(3):205-213
Dopaminergic agents and carbidopa/levodopa have become the preferred treatment for both the restless legs (RL) syndrome and for periodic limb movements in sleep (PLMS). For once-nightly treatments with carbidopa/ levodopa, a problem with morning end-of-dose rebound increases in leg movements has been reported to occur in the about one-fourth of the patients. In our clinical studies a previously unreported but far more significant problem of markedly augmented RL symptoms occurred in the afternoon and the evening prior to taking the next nightly dose. A systematic prospective evaluation of this augmentation in 46 consecutive patients treated with carbidopa/ levodopa for RL syndrome or PLMS disorder found this augmentation to be the major adverse effect of treatment. Augmentation occurred for 31% of PLMS patients and 82% of all RL patients. It was greater for subjects with more severe RL symptoms and for patients on higher doses (> or = 50/200 mg carbidopa/levodopa) but was unrelated to gender, age or baseline severity of PLMS. This augmentation was severe enough to require medication change for 50% of the RL patients and 13% of PLMS patients. Augmentation resolved with cessation of the medication and could be minimized by keeping the dose low. 相似文献
2.
1. Intracerebroventricular (i.c.v.) injection of choline (25-150 micrograms) increased blood pressure in rats made acutely hypotensive by haemorrhage. Intraperitoneal administration of choline (60 mg kg-1) also increased blood pressure, but to a lesser extent. Following i.c.v. injection of 25 micrograms or 50 micrograms of choline, heart rate did not change, while 100 micrograms or 150 micrograms i.c.v. choline produced a slight and short lasting bradycardia. Choline (150 micrograms) failed to alter the circulating residual volume of blood in haemorrhaged rats. 2. The pressor response to i.c.v. choline (50 micrograms) in haemorrhaged rats was abolished by pretreatment with mecamylamine (50 micrograms, i.c.v.) but not atropine (10 micrograms, i.c.v.). The pressor response to choline was blocked by pretreatment with hemicholinium-3 (20 micrograms, i.c.v.). 3. The pressor response to i.c.v. choline (150 micrograms) was associated with a several fold increase in plasma levels of vasopressin and adrenaline but not of noradrenaline and plasma renin. 4. The pressor response to i.c.v. choline (150 micrograms) was not altered by bilateral adrenalectomy, but was attenuated by systemic administration of either phentolamine (10 mg kg-1) or the vasopressin antagonist [beta-mercapto-beta,beta-cyclopenta-methylenepropionyl1, O-Me-Tyr2,Arg8]-vasopressin (10 micrograms kg-1). 5. It is concluded that the precursor of acetylcholine, choline, can increase and restore blood pressure in acutely haemorrhaged rats by increasing central cholinergic neurotransmission. Nicotinic receptor activation and an increase in plasma vasopressin and adrenaline level appear to be involved in this effect of choline. 相似文献
3.
4.
IH Robertson JB Mattingley C Rorden J Driver 《Canadian Metallurgical Quarterly》1998,395(6698):169-172
Patients with extensive damage to the right hemisphere of their brain often exhibit unilateral neglect of the left side of space. The spatial attention of these patients is strongly biased towards the right, so their awareness of visual events on the left is impaired. Extensive right-hemisphere lesions also impair tonic alertness (the ability to maintain arousal). This nonspatial deficit in alertness is often considered to be a different problem from spatial neglect, but the two impairments may be linked. If so, then phasically increasing the patients' alertness should temporarily ameliorate their spatial bias in awareness. Here we provide evidence to support this theory. Right-hemisphere-neglect patients judged whether a visual event on the left preceded or followed a comparable event on the right. They became aware of left events half a second later than right events on average. This spatial imbalance in the time course of visual awareness was corrected when a warning sound alerted the patients phasically. Even a warning sound on the right accelerated the perception of left visual events in this way. Nonspatial phasic alerting can thus overcome disabling spatial biases in perceptual awareness after brain injury. 相似文献
5.
The present study was undertaken to determine the effects of chronic sinoaortic (baroreceptor) denervation (SAD) on the hemodynamic and sympathetic alterations that occur in the pacing-induced model of congestive heart failure. Two groups of dogs were examined: intact (n = 9) and SAD (n = 9). Both groups of dogs were studied in the control (prepace) state and each week after the initiation of ventricular pacing at 250 beats/min. After the pacemaker was turned off, hemodynamic and plasma norepinephrine levels returned toward control levels in the prepaced state and after 1 and 2 wk of pacing. However, by 3 wk all hemodynamic and norepinephrine levels remained relatively constant over the 10-min observation period with the pacemaker off. With the pacemaker off, left ventricular end-diastolic pressure went from 2.7 +/- 1.4 (SE) mmHg during the prepace state to 23.2 +/- 2.9 mmHg in the heart failure state in intact dogs (P < 0.01). Left ventricular end-diastolic pressure increased to 27.1 +/- 2.2 mmHg from a control level of 4.2 +/- 1.9 mmHg i SAD dogs (P < 0.0003). Mean arterial pressure significantly decreased in intact and SAD dogs. Resting heart rate was significantly higher in SAD dogs and increased to 135.8 +/- 8.9 beats/min in intact dogs and 136.1 +/- 6.5 beats/min in SAD dogs. There were no significant differences in the hemodynamic parameters between intact and SAD dogs after pacing. Plasma norepinephrine was significantly lower in intact than in SAD dogs before pacing (197.7 +/- 21.6 vs. 320.6 +/- 26.6 pg/ml; P < 0.005). In the heart failure state, plasma norepinephrine increased significantly in both intact (598.3 +/- 44.2 pg/ml) and SAD (644.0 +/- 64.6 pg/ml) groups. There were no differences in the severity or the magnitude of the developed heart failure state in SAD vs. intact dogs. We conclude from these date that the arterial baroreflex is not the sole mechanism for the increase in sympathetic drive in heart failure. 相似文献
6.
A total of 120 gastro-intestinal tracts and 960 faecal samples were examined to assess the prevalence and seasonal changes in the gastro-intestinal helminth parasites of Red Sokoto (maradi) goats slaughtered at Ibadan between May 1991 and April 1992. Egg types of strongyles, Strongyloides, Trichuris, Skrjabinema, Dicrocoelium and Moniezia were encountered in 93%, 83%, 44%, 0.9%, 2.3% and 31% of the faecal samples respectively. However, only strongyle, Strongyloides and Trichuris eggs occurred in large numbers and were more common during the rainy season than in the dry season. The parasites recorded and their prevalences were Haemonchus contortus (90.0%), H. ovis (5.0%), Strongyloides papillosus (80.8%), Trichostrongylus colubriformis (78.3%), T. axei (69.2%), Trichuris ovis (72.5%), T. globulosa (38.3%), Oesophagostomum columbianum (67.5%), Cooperia curticei (58.3%) Gaigeria pachyscelis (40.8%), Skrjabinema ovis (5.0%), Nematodirus battus (5.8%), Moniezia expansa (29.2%), M. benedeni (10.0%), Paramphistomum spp. (5.0%) and Cysticercus tenuicollis (33.3%). Haemonchus ovis is reported for the first time in Nigeria. Mixed infections were most prevalent. Young goats were more commonly infected and had higher worm counts than adult goats. Only Haemonchus, Trichostrongylus, Strongyloides and Cooperia spp. occurred in large numbers. Irrespective of the age of the goats, higher worm counts were generally encountered during the rainy season than in the dry season. The results are discussed in relation to the control of helminthiasis in grazing animals in Nigeria. 相似文献
7.
8.
Epidemiological studies suggest the existence of a strong relationship between the incidence of prostatic cancer and the intake
of dietary lipids in humans. However, very little information is available on intracellular fatty acid metabolism in human
prostatic tissue. The objective of this study was to identify and subsequently characterize a fatty acid binding protein of
human prostatic tissue. A fatty acid binding protein (FABP) was purified and characterized from human prostatic tissue. The
purified FABP had an apparent molecular mass of 15.0±1.0 kDa as averaged from three different methods, sodium dodecylsulfate-polyacrylamide
gel electrophoresis (SDS-PAGE), gel filtration and amino acid analysis. The pI value of the protein was determined to be 6.8.
Scatchard analysis of fatty acid binding to the purified FABP from malignant prostatic tissue showed a Kd value of 0.53±0.02
μM for arachidonic acid (n=5). The Kd values of FABP purified from benign prostatic tissue were 0.57±0.02 μM for oleic acid
and 0.51±0.04 μM for arachidonic acid (n=5). Fatty acid analysis revealed that the level of endogenously bound arachidonic
acid was about 2.5-fold higher in FABP from malignant than from benign tissue. In addition, both malignant and benign tissues
contained the same concentration of FABP. The concentrations of FABP in malignant and benign tissues were 19.2±1.8 and 21.4±2.1
μg per mg of total cytosolic protein, respectively. Characterization based on amino acid composition, isoelectric point and
fluorescence with dansyl undecanoic acid suggests that the FABP may not be of the heart type, but is rather more closely related
to the liver type. As malignant prostatic tissue produces more PGE2 compared to benign tissue, our data suggest that FABP may help enhancing the synthesis of the prostaglandin in malignant
tissue by facilitating arachidonic acid transport.
A preliminary account of this work was presented at the Biochemical Society Meeting, London, December 16–18, 1991, and published
as an abstract (Ref. 1). 相似文献
9.
Chaudry Oliver Friedberger Andreas Grimm Alexandra Uder Michael Nagel Armin Michael Kemmler Wolfgang Engelke Klaus 《Magma (New York, N.Y.)》2021,34(3):367-376
Magnetic Resonance Materials in Physics, Biology and Medicine - To develop a precise semi-automated segmentation of the fascia lata (FL) of the thigh to quantify IMAT volume in T1w MR images and... 相似文献
10.
YJ Chwae IH Choi DS Kim EC Shin DH Kwon SJ Kim JD Kim 《Canadian Metallurgical Quarterly》1998,63(3):147-152
Videolaparoscopic cholecystectomy is considered the treatment of choice for simple cholelithiasis. Now many surgeons consider the laparscopic procedure usable also in the complicated biliary lithiasis like acute cholecystitis and choledocholithiasis. The authors report their recent experience of the laparoscopic treatment of biliary lithiasis, regarding 221 non-selected patients (69% symptomatic cholelithiasis, 20% chronic cholecystitis, 4.5% acute cholecystitis, 4.5% coledocolithiasis, 2% hydrops). The diagnostic-therapeutic protocol and the results are described and compared with the beginning of their experience, when they treated only symptomatic gallbladder stone disease, and with the reports of the literature. The authors concluded that the laparoscopic procedure is a good chance for the surgeon in the treatment of all cases of benign biliary disease. But, in particular for patients with choledocholithiasis, he has be able to know all the diagnostic and therapeutic possibilities, to choose the best in every single case. 相似文献