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101.
目的 :探讨用硝酸甘油加多巴酚丁胺治疗难治性心力衰竭。方法 :以阳泉钢铁集团有限公司医院 30例顽固性心力衰竭患者为研究对象 ,其中男性 18例 ,女性 12例 ,年龄 37岁~ 81岁 ,平均 5 6岁 ,心功能均为 级~ 级 ,在综合治疗同时 ,加用小剂量硝酸甘油加多巴酚丁胺开始 ,以后据病情逐渐增加剂量 ,把血压维持在正常水平 ,结果 :30例患者中 ,显效 2 0例 ,有效 9例 ,无效 1例 ,总有效率 96 .6 %。结论 :在强心、利尿等基础治疗的前提下 ,用硝酸甘油加多巴酚丁胺治疗难治性心力衰竭 ,既能通过多巴胺直接增强心肌收缩力作用 ,增加心排血量 ,提高血压 ,抵消硝酸甘油不良反应 ,可能发挥硝酸甘油扩张动、静脉 ,减轻心脏前后负荷 ,改善全身及肾血流灌注 ,在临床上值得进一步研究探讨 相似文献
102.
激光光凝联合玻璃体腔注气治疗玻璃体切割术后再发黄斑孔 总被引:1,自引:0,他引:1
目的 探讨激光光凝联合玻璃体腔注气治疗玻璃体切割术后再发与未愈黄斑孔的疗效。方法 应用COHERENT Omni多波长激光光凝黄斑裂孔底部的视网膜色素上皮层。随后眼内注入20%C3F80.5~0.8ml并置换出玻璃体腔液体。治疗后每天坚持俯卧位。结果 19只眼中16只眼黄斑孔愈合,成功率为84.2%,视力提高15只眼,占78.9%,未出现严重的并发症。结论 应用激光光凝联合眼内注气治疗玻璃体切割术后再发与未愈黄斑孔具有方法简单、费用低、疗效确定、大部分患者无须住院等优点。 相似文献
103.
Proximal tubular cells were loaded for 10 s with [3H]para-aminohippurate ([3H]PAH) by microperfusing the peritubular capillaries with Ringer solution containing 0.05 mmol/l PAH. Immediately thereafter
[3H]PAH influx from cells into a column of equilibrium solution injected into the oil-filled tubular lumen was measured by re-aspirating
the fluid after 1–10 s of contact time. The rise of luminal PAH concentration within 2 s of contact time was almost linear,
reaching a luminal / capillary concentation ratio of 1.6 after 2 s and of 3.2 after 5 s. The 2-s PAH concentration ratio was
not changed when different manoeuvres were applied to depolarize proximal tubular cells. Also, the 2-s PAH concentration ratio
was not influenced by varying the luminal pH from 6.0 to 8.0 or the luminal Cl–concentration from zero to 134 mmol/l or when either 5 mmol/l urate or 25 mmol/l lactate was in the luminal perfusate. A decrease
in the 2-s PAH concentration ratio, i.e. trans-inhibition, was observed when 25 or 50 mmol/l HCO3
–(–50%) was in the luminal perfusate. Trans-inhibition was also seen with 5 mmol/l of the following substituted benzoates:
2-hydroxy-benzoate (–58%), 2-methoxy-benzoate (–46%), 2-hydroxy-benzoate-acetyl ester (–36%), 2-hydroxy-3,5-dinitro-benzoate
(–48%), 3,5-dichloro-benzoate (–49%), and 2,3,5-trichloro-benzoate (–45%). No effect was seen with benzoate, 3-hydroxy-benzoate,
2-chloro-benzoate, 2-nitro-benzoate, 2,5-dinitro-benzoate, 3-sulfamoyl-benzoate and 4-sulfamoyl-benzoate. However, analogues
of the latter two compounds possessing two additional side groups, such as furosemide and piretanide, or a hydrophobic moiety,
such as probenecid, were inhibitory (by –62, –41 and –49% respectively). Phenoxyacetate had no effect; however, it inhibited
if in addition it had three chloro groups, as in 2,4,5-trichlorophenoxyacetate (–71%) or a hydrophobic carbamoyl side group,
as in mersalylic acid (salyrgan, –75%). Benzene-sulfonate trans-inhibited (–33%), as did phenolsulfonphthalein (phenol red,
–39%) and sulfofluorescein (–55%). However, the trans-inhibitory effect of the corresponding carboxy-compounds was absent
(phenolphthalein) or weaker (fluorescein, –42%). The trans-inhibitory effect of the uricosurics ethacrynic acid (–53%), tienilic
acid (–55%) indacrinone (–72%) and benzbromarone (–42%) could be attributed to two chloro or bromo side groups on the benzene
ring. Other trans-inhibiting uricosuric substances were indomethacin (–42%), sulfinpyrazone (–38%), losartan (–80%) its metabolite
EXP 3174 (–55%), and AA 193 (–65%). These organic acids, with pKa values between 2.8 and 4.9, possess chloro and sulfin groups, as well as heterocyclic 5-ring and hydrophobic ring or chain
areas. No significant effect was seen with 5 mmol/l PAH, 2-oxo-glutarate, DIDS, cGMP, prostaglandin E2, cortisol, benzylamiloride, pyrazinoic acid and 25 mmol/l lactate. Our data indicate that in situ the secretory luminal PAH
transport proceeds in a non-rheogenic fashion, per exclusionem by anion exchange. The observed trans-inhibition of PAH secretion seems to correlate with the affinity for the luminal PAH
transporter and, for uricosuric substances, with their uricosuric potency.
Received: 15 October 1996 / Received after revision: 17 December 1996 / Accepted: 18 December 1996 相似文献
104.
Pilot study to enhance HIV care using needle exchange-based health services for out-of-treatment injecting drug users 总被引:2,自引:0,他引:2
Altice Frederick L. Springer Sandra Buitrago Marta Hunt David P. Friedland Gerald H. 《Journal of urban health》2003,80(3):416-427
The introduction of highly active antiretroviral therapy (HAART) has resulted in marked reductions in mortality and acquired
immunodeficiency syndrome (AIDS) incidence across all risk groups; however, the proportionate decrease among injecting drug
users (IDUs) has been less impressive. Much of the disparity in benefit to IDUs has been a consequence of decreased access
to and receipt of potent antiretroviral combinations. Strategies to increase access to and utilization of HAART have included
entry into drug treatment and abstinence. Unfortunately, as few as 15%–20% of active drug users in the United States, and
in many other countries, are in drug treatment at any one time. We report a pilot project among out-of-drug treatment IDUs
infected with human immunodeficiency virus (HIV); HIV therapy was successfully provided to active heroin injectors using the
Community Health Care Van (CHCV) at sites of needle exchange. Subjects were willing to initiate, but were not receiving, recommended
HIV therapy and were not interested in formal drug treatment. Antiretroviral therapy regimens were selected and linked to
heroin injection timing. Weekly visits were scheduled by CHCV staff to assess adverse side effects and encourage adherence.
Of the 13 participants, the mean baseline HIV-1 RNA level and CD4 lymphocyte count were 162,369 (log 5.21) copies per milliliter
and 265 cells per milliliter, respectively. By 6 months, the proportion whose HIV-1 RNA was below the limits of detection
(<400 copies/mL) was 85% (N=11); 77% (N=10) had nondetectable levels by 9 months. By 12 months, 54% (N=7) had a persistently
nondetectable viral load, and the net increase in CD4 lymphocyte count was 150 cells per milliliter. As an additional and
unintended benefit of this pilot project, 9 (69%) subjects chose to enter drug treatment after achieving a nondetectable viral
load. Entry into drug treatment was associated with durability of viral suppression. This small pilot study suggests that
health services based on needle exchange may enhance access to HAART among out-of-treatment HIV-infected IDUs. In addition,
it demonstrates that this population can benefit from this therapy with the support of a nontraditional, community-based health
intervention. 相似文献
105.
目的探讨工程菌表达的耐热DNA聚合酶的纯化方法。②方法收集IPTG诱导带有耐热DNA聚合酶(TD聚合酶)基因表达质粒的工程菌株DH-TD4,用溶菌酶裂解,60℃处理后,上清液用硫酸铵沉淀,根据溶解度差异进行粗分级,然后进行离子交换层析细分级,并经聚合酶链式反应(PCR扩增)鉴定其活性。③结果纯化的TD聚合酶具有良好的聚合活性。④结论溶解度差异与离子交换层析是工程菌表达的耐热DNA聚合酶纯化的主要步骤。基因工程制备的DNA聚合酶可用于PCR检测 相似文献
106.
107.
Effects of isoflurane on oxygenation during one-lung ventilation in pulmonary emphysema patients 总被引:1,自引:0,他引:1
D. Satoh M. Sato A. Kaise Y. Hagiwara T. Saishu Y. Hashimoto 《Acta anaesthesiologica Scandinavica》1998,42(10):1145-1148
Background: Hypoxic pulmonary vasoconstriction has an important role in human one-lung ventilation (OLV) in the lateral decubitus position under general anesthesia. During OLV, inhalational anesthesia may inhibit hypoxic pulmonary vasoconstriction and the decrease in arterial oxygenation. We studied the effect of isoflurane administration on arterial oxygen tension in chronic obstructive pulmonary disease patients.
Methods: Ten patients who had thoracoscopic laser ablation of bullous emphysema were studied. Patients received 2% isoflurane in oxygen from induction until the first 20 min of OLV in the lateral decubitus position, then were switched to 1% isoflurane lasting 20 min and next were switched to 0.5% isoflurane lasting 20 min. After each 20-min inhalation, pulmonary and hemodynamic parameters were measured. The given concentrations for isoflurane were merely vapor meter concentrations.
Results: PaO2 /FIO2 , Qs/Qt respiratory rate peak inspiratory pressure and PaCO2 showed no significant changes at each point of isoflurane. Expiratory tidal volume significantly decreased (P<0.05) with 0.5% isoflurane compared to that with 2% isoflurane. Cardiac output, mean arterial pressure, mean pulmonary arterial pressure, systemic vascular resistance and pulmonary vascular resistance showed no significant changes at each point of isoflurane.
Conclusions: In patients with pulmonary emphysema, arterial oxygenation is not affected by low isoflurane concentration during OLV in the lateral decubitus position. 相似文献
Methods: Ten patients who had thoracoscopic laser ablation of bullous emphysema were studied. Patients received 2% isoflurane in oxygen from induction until the first 20 min of OLV in the lateral decubitus position, then were switched to 1% isoflurane lasting 20 min and next were switched to 0.5% isoflurane lasting 20 min. After each 20-min inhalation, pulmonary and hemodynamic parameters were measured. The given concentrations for isoflurane were merely vapor meter concentrations.
Results: PaO
Conclusions: In patients with pulmonary emphysema, arterial oxygenation is not affected by low isoflurane concentration during OLV in the lateral decubitus position. 相似文献
108.
Guillain-barré syndrome: A series observed at riyadh armed forces hospital january 1984–January 1994
A consecutive series of 47 hospitalized cases of Guillain-Barré syndrome seen over a 10-year period was analysed with respect
to: (1) age and sex; (2) antecedent events and seasonal distribution; (3) patterns of clinical presentation; (4) CSF and neurophysiological
findings; (5) results of treatment with plasma exchange; and (6) outcome. Twenty-two were children, 20 middle-aged and 5 aged;
37 were male and 10 were female. The most frequent antecedent event was upper respiratory tract infections; a seasonal peak
incidence was found in winter. Clinical, CSF and neurophysiological findings concurred with those in the Western literature;
79% of the cases were severe. Plasma exchange performed within the first 2 weeks of onset benefitted in the short-term outcome,
i.e. improvement by 1 grade at 4 weeks, but the long-term benefit, i.e. the ability to regain independent locomotion, was
questionable. Plasma exchange helped in curtailing the time to walking unaided but had no benefit on the duration of artificial
ventilation. Factors associated with an adverse outcome were: age over 15 years, severity of motor electrodiagnostic findings
(especially a decreased distal CMAP amplitude and EMG signs of acute denervation), requirement for ventilation and slow progression
(>3 weeks) to maximum deficit. After a mean follow-up of 11 months, 55% of the patients regained independent locomotion, which
is a comparatively low proportion. 相似文献
109.
Corporate influence on threshold limit values 总被引:4,自引:0,他引:4
Investigations into the historical development of specific Threshold Limit Values (TLVs) for many substances have revealed serious shortcomings in the process followed by the American Conference of Governmental Industrial Hygienists. Unpublished corporate communications were important in developing TLVs for 104 substances; for 15 of these, the TLV documentation was based solely on such information. Efforts to obtain written copies of this unpublished material were mostly unsuccessful. Case studies on the TLV Committee's handling of lead and seven carcinogens illustrate various aspects of corporate influence and interaction with the committee. Corporate representatives listed officially as "consultants" since 1970 were given primary responsibility for developing TLVs on proprietary chemicals of the companies that employed them (Dow, DuPont). It is concluded that an ongoing international effort is needed to develop scientifically based guidelines to replace the TLVs in a climate of openness and without manipulation by vested interests. 相似文献
110.
[目的] 介绍方剑乔教授针药结合治疗类风湿性关节炎的临床思辨特色及其临证经验。[方法] 通过整理、回顾、分析方教授治疗类风湿性关节炎的相关文献及医案,从中医病因病机和治则治法等方面,总结归纳方教授治疗类风湿性关节炎的学术经验,并列举医案一则予以佐证。[结果] 临床思辨上,方教授认为“痰、瘀、虚交错”为该病的基本病机,治疗宜针药结合,主要起到同效相须、异效互补和反效制约的作用。临证治疗上,方教授强调,针刺宜整体治疗与局部穴位兼顾,须重视经络辨证。合理应用电针,疼痛急性发作期电针频率多选择“先高后低”,先100 Hz/10~15 min,后2 Hz/30 min;慢性疼痛期电针治疗多选择疏密波(2/100 Hz)。用药强调精准辨证,在该病四种基本证型的基础上提出了阴虚湿热兼证的概念,确立了滋阴清热、通络止痛的治疗大法。倡导适时采用经皮穴位电刺激治疗,其操作简单,携带方便,在镇痛方面具有明显的优势。所举病案采用西药甲氨蝶呤片抑制免疫,稳定病情;中药以祛风除湿为主,佐以藤类药通络行窜、祛风止痛;电针治疗选择频率为2/100 Hz的疏密波调和气血、通络止痛。经治疗后,患者症状缓解,相关指标趋于正常。[结论] 方剑乔教授根据本病的病因病机及临床特点进行辨证论治,针药并重,中西医取长补短,临床特色鲜明,治疗效果显著,值得临床借鉴和推广。 相似文献