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111.
112.
为探讨成釉细胞纤维肉瘤( A F S)间叶细胞的本质及特征, 作者采用免疫组化和电镜技术,对3例 A F S间叶细胞进行了研究,并与6例成釉细胞纤维瘤进行比较。结果显示: A F S的间叶细胞主要由成纤维细胞构成,此外尚有少许未分化间叶细胞和组织细胞, 偶见肌纤维母细胞。成纤维细胞仅表现 Vim entin 阳性。肌纤维母细胞呈 Vim entin, H H F35及 α S M A 阳性。组织细胞 P G M1 和kp1标记均阳性, 可能是炎症或免疫反应的产物。与成釉细胞纤维瘤比较, A F S间叶细胞具备较高的 P C N A 阳性标记率, 提示 A F S的增生活性较高。 相似文献
113.
山羊肝精口服液是经多年临床经验及反复研究所得的成果,剂型恰当,工艺合理,质量可控,稳定性好。药效学试验说明,本制剂具有健壮身体,抗疲劳的功能。毒理学试验与临床观察说明山羊肝精口服液具有安全性。 相似文献
114.
S. Peat P. Sweet Y. Miah M. Barklamb U. Larsen 《European journal of clinical pharmacology》1999,55(8):577-581
Objective: This study evaluated Repro-Dose morphine (RDM; Reliadol from Nycomed Pharma), a new once daily controlled-release morphine
formulation, against twice daily MST Continus (MST) at steady state in patients with chronic opioid responsive pain.
Methods: A randomized double-blind two-way crossover design was used to evaluate the efficacy and adverse effects of RDM once daily
or MST twice daily, at the same total daily doses, in patients with chronic stable pain (dose range 20–120 mg per day). During
the RDM limb of the study active drug was administered in the evening and placebo in the morning. Dextromoramide was provided
as escape analgesia throughout the study. Following a 5-day screening period, during which stability of oral opioid dose was
verified, patients underwent two 5-day treatment periods, (one MST, one RDM) in random sequence. Pain scores, escape analgesia
requirements and side-effects were compared using data from days 3, 4 and 5 of each treatment period. Any events or medication
changes occurring during the study period thought liable to influence analgesia were regarded as protocol violations. Overall
assessment and period preference was assessed by direct questioning. RDM treatment was regarded as successful if the amount
of escape medication required during the RDM period was equal to or less than that required during the MST period.
Results: Forty-seven patients were included in the study, of whom 40 completed both periods [the intention to treat (ITT) population],
31 in strict accordance with the protocol [the per protocol (PP) population]. Results were similar for both populations. There
was no significant difference in pain scores or incidence of adverse events occurring during the MST and RDM periods. For
the ITT population, requirements for escape medication during the RDM period were less than, equal to or greater than those
recorded during the MST period for 14, 15, and 11 patients, respectively. Twenty-nine of 40 patients (72.5%) were therefore
RDM treatment successes (95% confidence interval 56.1–85.4%). The percentage of patients preferring RDM (45%) combined with
those with no preference (32.5%) was significantly higher than those preferring MST (22.5%; P = 0.0003).
Conclusions: Oral morphine administered as RDM once daily is at least as effective and well tolerated as MST twice daily, with over 70%
of patients in this double-blind crossover study reporting that RDM was equal or superior to MST.
Received: 6 April 1998 / Accepted in revised form: 23 January 1999 相似文献
115.
Faaij RA Srivastava N van Griensven JM Schoemaker RC Kluft C Burggraaf J Cohen AF 《European journal of clinical pharmacology》1999,54(12):929-935
Objective: Pentosan polysulphate sodium (PPS), a heparin-like drug, is supposed to be orally applicable. The objective of the present
study was to assess the oral bioavailability of PPS. However, since specific assays for PPS do not exist, this was done by
using primary and secondary effect parameters.
Methods: The study was carried out using a three-way randomized crossover design with 18 healthy young male volunteers. The subjects
received three treatments: PPS i.v. (50 mg), PPS orally (1500 mg) and placebo (orally). Blood sampling was done for activated
partial thromboplastin time (APTT), anti-Xa activity, hepatic triglyceride lipase, lipoprotein lipase, tissue plasminogen
activator (t-PA) activity, fibrin plate lysis, total triglyceride, total cholesterol, HDL and LDL.
Results: Intravenously administered PPS significantly increased APTT, anti-Xa activity, hepatic triglyceride lipase and lipoprotein
lipase compared with placebo in a magnitude comparable to other i.v. heparin-like compounds. Orally administered PPS did not
significantly influence any of the parameters when compared with placebo. Point estimates for the oral bioavailability of
PPS were in the range of 0% with small confidence intervals (CIs).
Conclusion: The oral bioavailability of PPS is negligible in young healthy males.
Received: 8 June 1998 / Accepted in revised form: 19 October 1998 相似文献
116.
Effects of continuous oral nicotine administration on brain nicotinic receptors and responsiveness to nicotine in C57Bl/6 mice 总被引:4,自引:4,他引:0
The route of drug delivery is an important consideration in studies that evaluate the long-term biobehavioral adaptations
that occur in response to chronic drug administration. Continuous infusions (intravenous or subcutaneous) or intermittent
intraperitoneal (or subcutaneous) injections are the most commonly utilized routes of chronic drug delivery in these studies.
The purpose of the present study was to determine the effects of chronic oral nicotine exposure on sensitivity to nicotine
and brain nicotinic cholinergic receptors in female C57Bl/6 mice. Mice were randomized to different treatment groups that
received 2% saccharin, containing 0–200 μg/ml nicotine (free base). In preliminary experiments, radiotelemetry devices were
implanted in the mice; consumption of the nicotine-containing drinking solution caused a significant increase in home-cage
nocturnal (but not diurnal) activity and also altered circadian alterations in body temperature. Oral nicotine exposure resulted
in dose-related elevations in plasma levels of cotinine, a primary nicotine metabolite. Continuous exposure (30 days) to oral
nicotine (200 μg/ml) resulted in the expression of significant tolerance to the locomotor depressant and hypothermic actions
of acute nicotine challenge. This tolerance was accompanied by a significant increase in brain nicotinic receptor number assessed
by quantitative autoradiography using [3H]-cytisine (α4 nAChr) and [125I]-α-bungarotoxin (α7 nAChr) as radioligands. These results suggest that chronic oral nicotine delivery to female C57Bl/6
mice results in behavioral and biochemical changes that resemble changes that occur following other routes of chronic nicotine
delivery.
Received: 30 January 1998 / Final version: 25 June 1998 相似文献
117.
Rationale: Progressive ratio (PR) schedules have become well accepted for testing the reinforcing effectiveness of drugs. This study
extends the methods to concurrent PR schedules with different concentrations of orally delivered phencyclidine (PCP). Objective: The sensitivity of the procedure is tested by presenting different PCP concentrations with independently-operating PR schedules.
Method: PCP self-administration was investigated in seven rhesus monkeys. Six different PCP concentrations (0.03–1.0 mg/ml) and
water were randomly paired (21 pairings). Liquid delivery (24 ml) was contingent upon lip-contact responses on solenoid-operated
drinking spouts; whereby, the response requirement or fixed-ratio (FR) increased (from 8 to 16, 32, 64, 128... to 4096) after
each successful completion of a previous FR and subsequent liquid delivery. Monkeys self administered PCP during daily 3-h
sessions, and each pair of concentrations was held constant until behavior had stabilized for at least 4 days. Results: The higher of the two PCP concentrations always maintained greater responding, PR break point (BP), or the last ratio completed,
and liquid deliveries than did the lower concentration. However, the monkeys did not exclusively respond on the drinking spout
that yielded the higher drug concentration. When examined across all drug pairings, the percentage of total available deliveries
of the higher concentration was significantly greater than those of the lower concentration. The monkeys maximized the amount
(mg) consumed for the response output. Responding, BPs and liquid deliveries maintained by 0.12 and 0.25 mg/ml PCP were significantly
greater than other PCP concentrations; however, drug intake (mg) increased directly with PCP concentration. Conclusion: These results indicate that concurrent PR schedules using oral drug self-administration and a concurrent choice paradigm
reliably provide an estimation of relative reinforcing strength, and behavior maintained by these schedules is sensitive to
small changes in PCP concentration.
Received: 18 September 1998 / Final version: 28 December 1998 相似文献
118.
Rationale: Opioid antagonists are used to reverse the toxic effects of opioids, to diagnose opioid dependence and to treat opioid and
other (alcohol) drug abuse. Objectives: This study compared the discriminative stimulus effects of two opioid antagonists (naloxone and naltrexone), after parenteral
and oral administration. Methods: The discriminative stimulus effects of naloxone and naltrexone were evaluated every 15 min over a 2-h period in four morphine-treated
(3.2 mg/kg per day) rhesus monkeys discriminating between subcutaneous (SC) injections of naltrexone (0.01 or 0.032 mg/kg)
and saline, while responding under a fixed-ratio 5 schedule of stimulus shock termination. Results: Within 15 min of SC administration, naloxone and naltrexone produced greater than 90% drug-appropriate responding at doses
of 0.032 and 0.01 mg/kg, respectively. The largest dose of naloxone (3.2 mg/kg) administered orally produced 82% drug-appropriate
responding within 90 min; the same dose of naltrexone administered orally produced greater than 90% drug-appropriate responding
within 30 min. Although both drugs were at least 100-fold more potent when administered SC, as compared to orally, there
was little difference (3-fold) between the potency of naloxone and naltrexone by either route. Conclusions: These results fail to support the view that naloxone has reduced bioavailability after oral administration, as compared
to naltrexone, or that its pharmacokinetic profile is particularly advantageous for some therapeutic settings (e.g. Talwin
Nx).
Received: 15 July 1998 / Final version: 21 December 1998 相似文献
119.
While anxiety appears to characterize humans who administer high doses of cocaine or experience withdrawal from cocaine, it is difficult to capture this aspect of cocaine effects in animals. The present study investigated if acute or protracted withdrawal from prolonged low-dose cocaine that is self-administered via the oral route could be detected in tactile startle and vocal distress responses of rats. Adult, male Long-Evans rats had access to cocaine solution (0.1 mg/ml) either for 24 or 4 h/day using the two-bottle choice technique. The amount of solution consumed from each bottle was measured daily for 30 or 60 days. On days 1, 3, 7, 14, 21, 28 of withdrawal, startle and ultrasonic vocal responses (USV, 15–35 kHz) were measured in response to 18 airpuff stimuli (20 psi). Rats drank an average of 5–20 mg/kg per day of the cocaine solution. On average, about half of the daily liquid was consumed from the cocaine solution-containing bottle. USVs were emitted at significantly increased rates on day 3 of withdrawal from 30 or 60 days of cocaine drinking. Startle reactions were slightly, but non-significantly increased on day 1 of withdrawal. Comparable to withdrawal from ethanol, morphine, and diazepam treatments, withdrawal from oral self-administration of low to moderate doses of cocaine increases the rate of ultrasonic vocalizations while increasing minimally the amplitude of startle responses to low-intensity tactile stimuli. Nevertheless, no correlation between the total amount of cocaine self-administered or the duration of treatment with the intensity of the withdrawal manifestations could be detected. 相似文献
120.
口服Ⅱ号避孕药对血小板功能及血液凝固的影响 总被引:2,自引:1,他引:1
为了解口服Ⅱ号避孕药对血小板功能及血液凝固性的影响,本文对65名连续服药妇女进行了研究。她们的年龄为27~45(平均36.5)岁。服药期限1~17(平均6.7)年。测定项目有纤维蛋白原,血小板粘附率,血小板聚集率,Ⅷ因子相关抗原,抗凝血酶活力等。20例未服药妇女作对照。测定结果服药组血小板粘附率、聚集率及纤维蛋白原比对照组明显增高(P<0.001)。Ⅷ因子相关抗原略增高,但无统计学意义。抗凝血酶活力显著降低(P<0.001)。本文就急性心肌梗塞及血栓栓塞的潜在可能性等问题进行了讨论,并对预防此类并发症提出了建议。 相似文献