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101.
Surendran Sabapathy Marc F Awater Donald A Schneider Rebecca A Kingsley Maria TE Hopman Norman R Morris 《INT J CHRONIC OBSTR》2006,1(1):73-81
We compared exercise capacity (peak O2 uptake; V̇O2peak) and lower limb vasodilatory capacity in 9 patients with moderate COPD (FEV1 52.7 ± 7.6% predicted) and 9 age-matched healthy control subjects. V̇O2peak was measured via open circuit spirometry during incremental cycling. Calf blood flow (CBF) measurements were obtained at rest and after 5 minutes of ischemia using venous occlusion plethysmography. While V̇O2peak was significantly lower in the COPD patients (15.8 ± 3.5 mL·kg−1·min−1) compared with the control group (25.2 ± 3.5 mL·kg−1·min−1), there were no significant differences between groups in peak CBF or peak calf conductance measured 7 seconds post-ischemia. V̇O2peak was significantly correlated with peak CBF and peak conductance in the control group, whereas no significant relationship was found between these variables in the COPD group. However, the rate of decay in blood flow following ischemia was significantly slower (p < 0.05) for the COPD group (−0.036 ± 0.005 mL·100 mL−1·min−1·s−1) when compared with controls (−0.048 ± 0.015 mL·100 mL−1·min−1·s−1). The results suggest that the lower peak exercise capacity in patients with moderate COPD is not related to a loss in leg vasodilatory capacity. 相似文献
102.
CHARLES C. TE M.D. STAVROS STAVRAKIS M.D. PEDRO LOZANO M.D. DWIGHT REYNOLDS M.D. F.H.R.S. 《Journal of cardiovascular electrophysiology》2013,24(2):224-226
Apparent Acute Reversible Right Ventricular Pacing‐Induced Left Ventricular Dysfunction . We report the case of a 70‐year‐old Caucasian male with a dual chamber (right atrium/right ventricle) pacemaker implanted for sinus node dysfunction and not pacemaker (PM) dependent who was found to have an apparent acute worsening of left ventricular (LV) function with right ventricular (RV) apical pacing caused by the mode switch to VVI pacing as battery depletion occurred. LV dysfunction resolved immediately with RV pacing turned off. To our knowledge, this is the first report of this phenomenon. (J Cardiovasc Electrophysiol, Vol. 24, pp. 224‐226, February 2013) 相似文献
103.
ANNELINE S.J.M. TE RIELE M.D. CYNTHIA A. JAMES Ph.D. BINU PHILIPS M.D. NEDA RASTEGAR M.D. ADITYA BHONSALE M.D. JUDITH A. GROENEWEG M.D. BRITTNEY MURRAY M.S. CRYSTAL TICHNELL M.G.C. DANIEL P. JUDGE M.D. JEROEN F. VAN DER HEIJDEN M.D. Ph.D. MAARTEN J.M. CRAMER M.D. Ph.D. BIRGITTA K. VELTHUIS M.D. Ph.D. DAVID A. BLUEMKE M.D. Ph.D. STEFAN L. ZIMMERMAN M.D. IHAB R. KAMEL M.D. Ph.D. RICHARD N.W. HAUER M.D. Ph.D. HUGH CALKINS M.D. HARIKRISHNA TANDRI M.D. 《Journal of cardiovascular electrophysiology》2013,24(12):1311-1320
104.
PHILIPPE BRUNEL M.D. ASHOK TIROUVANZIAM M.D. ROBERT GROSSETÊTE M.D. DOMINIQUE CROCHET M.D. 《Journal of interventional cardiology》2000,13(2):117-121
This study reports our preliminary experience of percutaneous coronary angioplasty with low dose heparin and immediate withdrawal of the femoral sheath. After selection, 120 patients underwent a procedure with a low dose of heparin (4,300 ± 700 IU). A total of 120 of 123 lesions (97.6%) were treated successfully by the femoral route. There were no major cardiac complications during the procedure and hospital stay. Patients were allowed to be ambulant 6 hours after the procedure. No significant bleeding occurred. There was no need for surgery relative to the approach route nor for blood transfusion. The use of low dose heparin and immediate withdrawal of the femoral sheath did not increase the risk of coronary angioplasty in these selected patients. The period of bed confinement was shortened and the patients were ambulant earlier, leading to a reduction in their hospital stay with no increase in costs. 相似文献
105.
目的 :诱导出贯叶金丝桃的愈伤组织 ,并确定其中含有金丝桃素。方法 :在不同条件下采用组织培养技术 ,进行贯叶金丝桃的愈伤组织诱导研究 ,用HPLC方法确定其中含有的金丝桃素。结果和结论 :最佳诱导条件是MS基本培养基加入生长调节物质 2 ,4 D(4μg·L- 1 )和 6 BA(0 .2 μg·L- 1 )。叶腋等分生组织较多的部位易于诱导愈伤组织。诱导出的愈伤组织 ,经HPLC方法确定其含金丝桃素 相似文献
106.
107.
M Livio P M Mannucci G Viganò G Mingardi R Lombardi G Mecca G Remuzzi 《The New England journal of medicine》1986,315(12):731-735
Bleeding is a major complication of uremia. Both cryoprecipitate and desmopressin effectively shorten the prolonged bleeding time and favorably influence clinical bleeding, but the former carries the risk of transmitting blood-borne infectious diseases, and both cryoprecipitate and desmopressin have a short duration of action. Preliminary evidence has suggested that estrogens may be useful, and we therefore performed a randomized, double-blind, crossover trial comparing the effect of conjugated estrogens with that of placebo on hemorrhagic tendencies and the bleeding time in six patients with uremia who were on maintenance hemodialysis. Five daily infusions of placebo or conjugated estrogens were administered at the beginning of one-month trial periods. Estrogen shortened the bleeding time in all six patients. The effect was detectable six hours after the first infusion, reached its maximum in all patients between days 5 and 7, and lasted for 14 days. By day 16 after the last infusion, the bleeding time had returned to base line in four of the six patients. No side effects were noted during or after estrogen infusion. Estrogens did not influence the circulating level of von Willebrand factor or change its multimeric structure. Moreover, the defective platelet aggregation and thromboxane formation observed in the patients were not corrected by estrogens. We conclude that conjugated estrogens are an adequate alternative to cryoprecipitate or desmopressin for the treatment of bleeding associated with renal failure, especially when a longer duration of action is needed and immediate onset of the effect is not essential. The mechanism of action of estrogens remains to be clarified. 相似文献
108.
张志利 《中华微生物学和免疫学杂志》1994,(3)
NOD鼠是人类胰岛素依赖型糖尿病的动物模型,其发病与自身免疫有关。环磷酰胺(CP)可以加速这一过程,使NOD鼠糖尿病的发病率提高或提前。一些研究表明:NOD鼠的淋巴细胞在淋巴细胞混合反应中(MLR),在有或无刺激物的存在下,白细胞介素2(IL-2)的产量均明显低于正常鼠的淋巴细胞。该实验对注射了一次大剂量的CP(300mg/kg体重)后的NOD鼠试用了IL-2治疗。结果显示:对于年幼的NOD鼠IL-2治疗14无可以明显减轻注射CP后的胰岛破坏加速。病理检查显示三组胰岛炎严重程度积分分别为29;81;88。IL-2处理组明显低于ConA处理组与对照组。这个研究还显示,对于12周龄的NOD鼠,经14天的IL-2治疗,可以完全预防CP诱导的糖尿病的发生。糖尿病发病率在IL-2组为0/12;对照组为7/12。但对已发病的NOD鼠自发性糖尿病IL-2不能使其缓解。 相似文献
109.
110.
Naysmith TE; Blake DA; Harvey VJ; Johnson NP 《Human reproduction (Oxford, England)》1998,13(11):3250-3255
This study was designed to assess the effect of cancer treatments on the
natural and assisted reproductive potential of men. A cohort of men with
cancer, in whom radiotherapy and/or chemotherapy was planned, were invited
to participate. Twenty-two pre- and post-treatment semen samples were
analysed. The reproductive potential of participants was assessed with
respect to the current range of fertility treatment options available.
Abnormal sperm concentrations were found in 27% of patients pre-treatment
compared to 68% post-treatment following a mean latency of 20 months from
treatment. Fifty-nine percent of patients experienced a clinically
significant decrease in sperm, concentration following radiotherapy and/or
chemotherapy; 23% developed azoospermia following treatment. Eighty-two
percent of patients with testicular malignancy had oligo- or azoospermia
post-treatment. Only one patient had a clinically significant reduction in
the percentage of motile spermatozoa post-treatment. Cryopreservation of
semen prior to treatment improved the fertility prospects of 55% of
patients. Intracytoplasmic sperm injection (ICSI) enhanced the fertility
prospects of a further 14%. In the absence of, or after depletion of,
cryopreserved semen, ICSI could enhance the fertility prospects of 45% of
patients. Fertilization has been achieved by ICSI using spermatozoa
retrieved by testicular biopsy from an azoospermic testicular cancer
survivor 8 years after chemotherapy. It was concluded that chemotherapy
and/or radiotherapy may depress semen concentration to the extent of
rendering a man infertile. The severity of the reduction in sperm
concentration following treatment is unpredictable but likely to be most
severe in those with testicular malignancy and those treated with
radiotherapy or alkylating chemotherapy agents. Not all men are keen to
undergo an appraisal of their post-treatment fertility potential, for
reasons which are unclear. Improving awareness and education of patients
concerning the effects of both cancer and cancer treatments on reproductive
potential is essential. With the advent of ICSI, it is possible to offer a
very reasonable chance of conception in all men with cancer who present for
cryopreservation of semen prior to treatment in whom spermatozoa (even in
very low concentrations) are present in the ejaculate.
相似文献