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排序方式: 共有1253条查询结果,搜索用时 15 毫秒
1.
清咽雾化液为紫红色澄明灭菌溶液,经95例急慢性咽喉炎临床治疗观察,其临床痊愈率与显效率为81.04%,与对照组比较有显著差异。药效研究具有抗炎消肿、镇咳祛痰、改善微循环、增强免疫功能等作用。其可以提高患者唾液中IgG水平,且具有统计学差异。 相似文献
2.
HPLC法测定七味清咽气雾剂中苦参碱的含量 总被引:2,自引:0,他引:2
目的:用HPLC测定七味清咽气雾荆中苦参碱的含量。方法:采用高效液相法,使用Shim-pack VP-ODS色谱柱,以乙腈珈.2%三乙胺溶液(1.4:98.6)用磷酸调至pH为2.5,柱温为55℃,流速为0.7mL/min,检测波长为214mn。结果:苦参碱在64.4~1030μg范围内呈良好的线性关系(r=0.9997),回收率为98.6%,RSD为0.9%。结论:方法灵敏、准确、专属性强,回收率高,重现性好,可作为七味清咽气雾剂的质量标准。 相似文献
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Luigi Marazzini Andrea Pelucchi Marina Bozzoni Berardino Mastropasqua Erminio Longhini 《Journal of clinical immunology》1985,5(3):195-203
The role of adrenergic mechanism in the pathogenesis of allergic disease is controversial. Recent experimental and clinical reports have suggested that -adrenergic blockade impairs and stimulation enhances extrarenal potassium uptake in humans. This led us to study the effect of the intravenous administration of salbutamol, a specific -2-adrenergic agonist, on serum potassium in 9 healthy subjects and in 23 patients with allergic asthma and/or rhinitis. Serum potassium fell significantly and reached a peak decline at the end of venous infusion in all the normal subjects. Seventeen atopic subjects showed a lower or absent serum K+ decrement: there was no difference between asthmatic and rhinitic patients. There was no relation among the salbutamol-induced serum potassium decrement, serum glucose increment, blood pressure and heart-rate changes, and nonspecific bronchial reactivity. These findings suggest that -2-adrenergic hyporesponsiveness is present only in some allergic patients. 相似文献
6.
Simeon P. Cairns John A. Flatman Torben Clausen 《Pflügers Archiv : European journal of physiology》1995,430(6):909-915
An increased extracellular K+ concentration ([K+]0) is thought to cause muscle fatigue. We studied the effects of increasing [K+]0 from 4 mM to 8–14 mM on tetanic contractions in isolated bundles of fibres and whole soleus muscles from the rat. Whereas there was little depression of force at a [K+]0 of 8–9 mM, a further small increase in [K+]0 to 11–14 mM resulted in a large reduction of force. Tetanus depression at 11 mM [K+]o was increased when using weaker stimulation pulses and decreased with stronger pulses. Whereas the tetanic force/resting membrane potential (E
M) relation showed only moderate force depression with depolarization from –74 to –62 mV, a large reduction of force occurred whenE
M fell to –53 mV. The implications of these relations to fatigue are discussed. Partial inhibition of the Na+-K+ pump with ouabain (10–6 M) caused additional force loss at 11 mM [K+]0. Salbutamol, insulin, or calcitonin gene-related peptide all stimulated the Na+-K+ pump in muscles exposed to 11 mM [K+
0] and induced an average 26–33% recovery of tetanic force. When using stimulation pulses of 0.1 ms, instead of the standard 1.0-ms pulses, force recovery with these agents was 41–44% which was significantly greater (P < 0.025). Only salbutamol caused any recovery ofE
M (1.3 mV). The observations suggest that the increased Na+ concentration difference across the sarcolemma, following Na+-K+ pump stimulation, has an important role in restoring excitability and force. 相似文献
7.
K.-M. Zhang Ping Hu Shang-Wu Wang Leon D. Wright Andrew S. Wechsler John A. Spratt F. N. Briggs 《Pflügers Archiv : European journal of physiology》1998,435(4):511-517
Chronic administration of salbutamol induced expression of hybrid fibers in canine skeletal muscles. Fast-twitch fibers expressed
SERCA2a (the slow-twitch isoform of sarcoplasmic reticulum Ca2+-ATPase) and slow-twitch fibers expressed SERCA1 (the fast-twitch isoform of the Ca2+-ATPase). The proportion of fibers that became hybrid increased from a small percentage in the control muscles to 30% in the
predominantly fast-twitch latissimus dorsi and to 45% in the predominantly slow-twitch vastus intermedius. In contrast to
this response by the SERCA genes the phospholamban gene response was muscle specific. The fraction of fibers that expressed
phospholamban decreased slightly in the latissimus dorsi while increasing moderately in the vastus intermedius. The effects
of chronic neurostimulation of the latissimus dorsi on SERCA1, SERCA2a and phospholamban levels were mostly blocked by salbutamol.
While 100% of fibers from neurostimulated muscles expressed phospholamban, only 51% of the fibers from the neurostimulated
and salbutamol-treated muscles expressed it. In the neurostimulated muscle, very few muscle fibers expressed SERCA1a while
61% of the fibers that received salbutamol expressed it, albeit as hybrid fibers. The levels of SERCA2a in response to these
interventions were just the opposite. In the neurostimulated muscle 37.5% of fibers were hybrid and 62.5% expressed SERCA2a
only. With co-administration of neurostimulation and salbutamol, 61.3% of fibers were hybrid and 38.7% expressed SERCA2a only.
Received: 4 July 1997 / Received after revision: 16 October 1997 / Accepted: 30 October 1997 相似文献
8.
目的 研究紫外线照射对腺病毒气溶胶活力和粒级分布的影响.方法 在2000L的腔室中通过TK-3微生物气溶胶发生器将绿色荧光蛋白(GFP)标记的腺病毒形成气溶胶,暴露在预先设定波长的紫外线下,用多级撞击式空气微生物采样器进行采样.对采样样品进行实时荧光定量PCR(FQ-PCR)检测基因组拷贝数.通过在荧光显微镜下计数带绿色荧光的PK15细胞数可直观检测病毒的感染力及活力.结果 带有绿色荧光的PK15细胞数及FQ-PCR检测结果均提示所采集的病毒气溶胶主要分布在第6级.波长为254 nm的紫外线照射5 min时,在显微镜下观察到的荧光数明显减少.波长为254 nm紫外线照射30 min时,6个级别的细胞内均未见绿色荧光.波为365 nm紫外线照射30 min时,绿色荧光数仍较多.波长为254 nm的紫外线照射30 min时没有观察到有绿色荧光的细胞,但是FQ-PCR结果提示病毒基因组拷贝数仍较高.结论 波长为254 nm的紫外线比365 nm的紫外线照射灭活腺病毒气溶胶的效果更显著.两种波长的紫外线照射对腺病毒气溶胶的粒级分布没有显著影响.病毒基因组的存在并不能代表病毒有感染力. 相似文献
9.
In situ characterization of oxalate transport across the basolateral membrane of the proximal tubule
E. Brändle U. Bernt Richard E. Hautmann 《Pflügers Archiv : European journal of physiology》1998,435(6):840-849
Oxalate transport across the contraluminal membrane of the proximal tubule was studied in vivo using the ”capillary stopped
flow microperfusion method” (Pflügers Arch 400:250–256, 1984). Cellular uptake of oxalate was characteristic of a carrier-mediated
transport process (J
max = 1.6 ± 0.6 pmol/s per cm proximal tubular length, K
m = 2.03 ± 0.77 mmol/l). Sulphate inhibited oxalate transport in a dose-dependent manner (K
i-value = 1.53 ± 0.38 mmol/l). Sulphate transport across the basolateral membrane was also characteristic of a carrier- mediated
transport process (Jmax = 1.83 ± 0.56 pmol/s per cm proximal tubular length, K
m = 1.37 ± 0.57 mmol/l). Oxalate inhibited the sulphate transport in a dose-dependent manner (K
i = 2.06 ± 0.82 mmol/l). No significant differences were found between the K
i values and the K
m values of the two substances, indicating that oxalate and sulphate are transported by the same carrier across the basolateral
membrane of the proximal tubule. Oxalate transport was not dependent on the extracellular sodium or potassium concentration.
Bicarbonate competitively inhibited the oxalate transport. Chloride significantly inhibited the oxalate transport, but not
dose dependently. It is, therefore, suggested that oxalate is transported into the cell of the proximal tubule in exchange
for sulphate or bicarbonate. The dose-independent inhibition by chloride is suggested to be mediated by the coupling of the
sulphate (bicarbonate)/oxalate exchanger with the chloride/bicarbonate exchanger at the basolateral membrane of the proximal
tubule. This, furthermore, suggests that the transport of oxalate or sulphate across the basolateral membrane might be indirectly
coupled with the reabsorption of chloride at this membrane side.
Received: 5 August 1997 / Accepted: 8 January 1998 相似文献
10.
Jeffrey M. Liebman Nancy R. Hall James Prowse Susan Gerhardt Linda Noreika Howard M. Fenton 《Psychopharmacology》1984,84(3):336-341
The effects of -adrenoceptor agonists were compared in various operant behavioral tasks, particularly intracranial self-stimulation (ICSS). Clenbuterol, salbutamol, and terbutaline all reduced responding by rats that lever-pressed for low stimulation intensities. The effects of clenbuterol in this test were completely reversed by propranolol, and those of salbutamol were partly reversed. Intermediate doses of clenbuterol and salbutamol slowed the initiation of rewarding brain stimulation in a shuttlebox but had little or no effect on the termination latencies. However, higher doses of both drugs lengthened the termination latencies. Motor activity was reduced at doses that attenuated ICSS responding. Complete tolerance occurred within 4 days to the effects of clenbuterol and salbutamol on leverpressing ICSS and to the effects of clenbuterol on motor activity. The apparent performance deficits induced by these drugs were overcome by more intense motivation. For example, even at high doses, clenbuterol reduced ICSS leverpressing only partially when animals bar-pressed for high rather than low stimulation intensities. Furthermore, all three drugs failed to alter Sidman avoidance responding at doses up to 100 times those that attenuated ICSS responding. It is concluded that although -adrenoceptor agonists cause apparent sedation in rats, this sedation is limited and shows rapid tolerance. 相似文献