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21.
The effects of electrical stimulation and microinjection of sodium glutamate (0.5 M) in the sympathetic pressor areas of the dorsal medulla (DM), ventrolateral medulla (VLM), and parvocellular nucleus (PVC) on the knee jerk, crossed extension, and evoked potential of the L5 ventral root produced by intermittent electrical stimulation were studied in 98 adult cats anesthetized with chloralose and urethane. During electrical and glutamate stimulation of these pressor areas, in addition to the rise of systemic arterial blood pressure marked inhibition of the spinal reflex was produced, indicating presence of neuronal perikarya responsible for these actions. Mild to moderate augmentation of spinal reflexes was also observed during brain stimulation but only in a few cases. The magnitude of the somatic effects among the pressor areas of the VLM, DM, and PVC subsequent to glutamate activation was about the same. Induced spinal reflex inhibition, independent from the baroreceptor and vagal influence, remained essentially unaltered after acute midcollicular decerebration. The inhibition was also observed in cats decerebellated 8-10 days in advance. The inhibition was not affected after bilateral electrolytic- or kainic-acid-induced lesions in the paramedian reticular nucleus (PRN). On the contrary, PRN-induced spinal reflex inhibition was attenuated after bilateral lesions in the DM or VLM. Data suggest that there coexists neuronal subpopulations in the VLM, DM, and PVC that can affect both the sympathetic pressor systems and spinal reflexes.  相似文献   
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B L Su 《中华外科杂志》1989,27(10):587-90, 637
Talipes valgus, mostly resulted from poliomyelitis, of 44 feet in 43 children, aged 4 to 12 years, were treated by Grice extra-articular arthrodesis of the subtalar joint, and on 36 of them tendon transfer was done as well at the same time. The result in all of them, after a period of 15.3 years (ranging 5 to 23 yrs.), was found satisfactory in 32 feet (72.7%), and unsatisfactory in 12 (27.3%). Eight of the latter were found to be due to secondary varus deformity, a consequence of imbalance of muscle power following medial transfer of peroneal tendon (s). It is emphasized that in correcting foot deformity, slight valgus is receptible while over correction (varus) must be avoided. It is also found that after subtalar stabilization, traumatic osteoarthritis of midtarsal and ankle joints developed more frequently in patients who had better limb function than in those whose limbs had functioned much less.  相似文献   
24.
Usually, a drug is loaded onto the metallic surface of a medical device by applying a polymer layer containing the drug. Unfortunately, polymer coatings on the metallic surface may exhibit numerous problems after implantation, such as late thrombosis, inflammation, and restenosis. Current research was conducted to investigate whether a suitable oxide layer can be used as a polymer-free platform for drug loading, especially for cardiovascular stents. The loading of heparin onto, as well as eluting of heparin from, the amorphous oxide film on the 316LVM stainless steel wire was confirmed by experimental studies using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), electron spectroscopy for chemical analysis (ESCA), high-performance liquid chromatography (HPLC), and activated clotting time (ACT). Evidence shows that amorphous oxide can be an ideal substitute for the polymer coating of drug-loaded stents to minimize metallic corrosion, inflammation, late-thrombosis, and restenosis.  相似文献   
25.
Four cases of baclofen intoxication are reported, with a review of 33 cases from the literature. Analysis of these 37 cases suggests that there are two types of baclofen intoxication syndrome. Patients with acute intoxication present with four major clinical manifestations: encephalopathy (disturbance of consciousness and/or seizure), respiratory depression, muscular hypotonia, and generalized hyporeflexia. Patients with chronic intoxication present with hallucinosis, impaired memory, catatonia, or acute mania. The acute intoxication syndrome has a faster onset, shorter duration, more severe clinical manifestations, and higher incidence of seizures than the chronic intoxication syndrome. Baclofen intoxication, although it may cause grave encephalopathic manifestations and electroencephalographic findings, has a benign outcome if actively managed.  相似文献   
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Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions.  相似文献   
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Background Previous studies have noted that there is a high utilization rate of traditional Chinese medicine (TCM) services in Taiwan, China and in western countries, but few studies investigated factors associated with the utilization of TCM in Taiwan. This study analyzes the utilization rate and the factors associated with the utilization of TGM in Taiwan. Methods Data for this study were from the 2002 HPKAP Survey that conducted the face-to-face questionnaire interviews of people aged 15 years and over from October 2002 to March 2003 in Taiwan. This study analyzed the utilization of TCM outpatient services, including admission to the hospital and clinic visits. Results A total of 26 755 participants completed the survey in the six-month period. The data revealed that 10.4% of participants had utilized TCM services in the past one month while 4.2% of participants utilized TCM only (without using Western medicine outpatient services (WM) or Folk therapy (F'I')). The average visits of TCM services per patient was higher among people who had utilized TCM and FT services (2.68 visits) than among those who had utilized WM and FT services (2.15 visits) or TCM services alone (2.15 visits) during the previous one month. Younger people (odds ratio OR= 1.78, 95%C/= 1.47-2.16), women (compared with men), and people with higher education levels (OR = 1.58, 95%CI =1.25-1.98) were more likely to visit TCM than compared groups. People with self-reported poor health status (OR = 2.07,95%CI = 1.76-2.44) and people who exercise regularly (OR = 1.17, 95%CI = 1.07-1.27) had higher ORs to visit TCM service than comparison group.Conclusions There is a high utilization of TCM in Taiwan. Further studies are needed to investigate the related factors and determinants between the utilization of TCM and the utilization of FT in Taiwan.  相似文献   
30.
Performance measurement of the microPET focus 120 scanner.   总被引:6,自引:0,他引:6  
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.  相似文献   
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