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81.
82.
Summary— In recent years, two key concepts having numerous interrelationships were advanced for the understanding of various cardiovascular diseases: the “endothelial dysfunction” and the “arterial remodelling”. Both endothelial dysfunction and arterial remodelling occur in various pathologies including essential hypertension, heart failure, atherosclerosis, restenosis after angioplasty, and pulmonary hypertension, and have modified the therapeutic approach by offering new pharmacological targets: specific receptors not only at the site of the vascular smooth muscle cells but also on the endothelial cells, growth factors that stimulate proliferation of smooth muscle, and receptors and enzymes of the extra-cellular matrix. Among the various substances under research, the present review will discuss angiotensin II receptor antagonists, endothelin receptor antagonists, nitrates-NO donors, potassium channel activators, and substances interfering with proteoglycans and other components of the extra-cellular matrix.  相似文献   
83.
We instilled naphazoline Hcl (0.1%), an imidazole derivative with preferential alpha-2 activity, in 17 eyes of 12 patients with myopathic ptosis due to involvement of the levator palpebrae superioris, in the attempt to selectively stimulate Müller's smooth muscle. Naphazoline significantly widened the palpebral fissure with little change in pupillary diameter and no significant change in ocular pressure, visual acuity and near point determination. However, a reduction of the effect, probably due to tachyphylaxis, was noticed when using naphazoline regularly several times a day for few weeks. In conclusion naphazoline has powerful cosmetical and functional effects in mild to moderate myopathic ptosis above all if taken occasionally.  相似文献   
84.
85.
Human breast cancer in vivo: H-1 and P-31 MR spectroscopy at 1.5 T   总被引:3,自引:0,他引:3  
To assess the potential of in vivo magnetic resonance (MR) spectroscopy for breast cancer, hydrogen-1 and phosphorus-31 MR spectra of five malignant human breast tumors were compared with those of unaffected breast tissue. The water-to-fat ratio was high in the tumors (average, 2.2) but low in the unaffected tissue (average, 0.3). The P-31 spectrum of normal breast tissue showed low levels of phosphomonoesters (PMEs), inorganic phosphate, phosphodiesters (PDEs), and ATP. In addition, an intense phosphocreatine (PCr) signal was observed in breast tissue of young women: The relative intensities of the PCr and ATP signals had a mean value of 1.9. The tumor spectrum showed elevated levels of PMEs, Pi, and PDEs, while no PCr was seen (PCr/ATP less than 0.2). In two breast cancers treated with radiation therapy, resulting in a decrease of tumor volume of more than 50%, a similar change in the tumor P-31 spectrum was observed: An intense PCr signal developed (PCr/ATP = 1.1). Control experiments indicated that the appearance of PCr after radiation therapy was the result of a radiation-induced metabolic change in the tumor itself.  相似文献   
86.
87.
Sympathetic nervous control of cat ileocecal sphincter   总被引:1,自引:0,他引:1  
  相似文献   
88.
New prognostic factors in resectable non-small cell lung cancer.   总被引:1,自引:1,他引:0       下载免费PDF全文
E F Smit  H J Groen  T A Splinter  T Ebels    P E Postmus 《Thorax》1996,51(6):638-646
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89.
Non-invasive methods for assessment of the vascular effects of antimigraine drugs were evaluated with respect to their utility, variability and sensitivity in a double-blind, placebo-controlled, three-period crossover study in six healthy volunteers using an intravenous vasoconstrictor, methoxamine, as a probe drug. Changes in the internal diameter of the brachial and radial arteries were measured using ultrasound which had low between-day and within-day coefficients of variation. Peak systolic velocity (PSV), time-averaged velocity (TAV), total flow, resistance (RI) and pulsatility indices (PI) were measured by Doppler from one arterial wave form. Whilst PSV and TAV increased with methoxamine, because of bradycardia, changes in PI and RI were difficult to interpret. An automatic oscillametric cuff, a mercury-in-silastic strain gauge method and the "Finapres", finger arterial blood pressure monitor were used to follow changes in systolic blood pressure (SBP). The strain gauge technique underestimated arm SBP compared to the oscillometric method but clearly showed drug-related increases whilst the Finapres did not reflect changes in blood pressure detected by the other methods.  相似文献   
90.
Symptomatic brain metastases are found in about 40% of patients with small cell lung cancer. Cranial irradiation is the first line treatment for this form of metastatic disease. Frequently brain metastases recur after this treatment or develop after prophylactic cranial irradiation. For these patients no effective antitumour therapy is available. In this study the efficacy of high dose etoposide 1.5 g m-2 was evaluated. In 10 (43%) out of 23 evaluable patients a response was seen. Toxicity was severe with five aplasia-related deaths. For palliative purposes this regimen is too toxic in heavily pretreated patients.  相似文献   
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