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61.
A short-term clinical study on the effect of purified angiogenic and growth factors from human term placenta in the treatment of chronic varicose ulcers was carried out in 18 patients. Patients were randomly allocated to receive a maximum of two dressings containing or not containing these factors. The amount of granulation and epithelial tissue was clinically estimated 48 hours after each application. Patients treated with placental angiogenic and growth factors showed increased granulation and epithelial tissue. These results indicate that placental factors may be used for acceleration of wound healing.  相似文献   
62.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
63.
Using a dummy test driver with a simulated flaccid forearm capable of representing either a large or zero friction condition, six powered wheelchairs were examined for bucking tendencies. In the zero friction condition, bucking was easily induced in 5 of 6 tested wheelchairs. Adding friction to the simulated forearm prevented bucking in all tested wheelchairs but one. Bucking is not simply related to wheelchair performance measures such as speed or acceleration. Sustained bucking corresponds to neutral stability in a speed regulated machine. Changes in natural frequency and damping characteristics are predicted as useful in reducing powered wheelchair bucking.  相似文献   
64.
Striatal particulate preparations, both from rats with lesion-induced striatal dopamine (DA) loss and from some striatal dopamine (DA) loss and from some patients with Parkinson's disease, exhibit increased 3H-neuroleptic binding, which is interpreted to be the mechanism of denervation-induced behavioral supersensitivity to dopaminergic compounds. After intravenous 3H-spiperone (3H-SP) administration to rats with unilateral nigral lesions, we found no differences in accumulation of total or particulate-bound 3H-SP in dopamine-denervated compared with intact striata. 3H-SP in vivo binds to less than 10% of striatal sites labeled by 3H-SP incubated with striatal particulate preparations in vitro. Quantitative autoradiography of 3H-SP binding to striatal sections in vitro also failed to reveal any effects of dopamine denervation. 3H-SP bound to striatal sites in vivo dissociates more slowly than that bound to striatal particulate preparations labeled in vitro. Striatal binding properties of 3H-SP administered in vivo are quite different from the same kinetic binding parameters estimated in vitro using crude membrane preparations of striatum. In addition, striatal binding of in vivo-administered 3H-SP is not affected by prior lesion of the substantia nigra, which results in profound ipsilateral striatal dopamine depletion. Thus, behavioral supersensitivity to dopaminergic compounds may not be associated with altered striatal binding properties for dopamine receptor ligands in vivo.  相似文献   
65.
OBJECTIVE: To assess the use of infiltration with local anaesthetics levobupivacaine and bupivacaine, during inguinal hernia repair. DESIGN: Double-blind, randomised study. SETTING: Postgraduate medical school, United Kingdom. SUBJECTS: 69 male patients aged 18 years or older. INTERVENTIONS: Wound infiltration with 0.25% levobupivacaine and 0.25% racemic bupivacaine. MAIN OUTCOME MEASURES: Area under the curve (AUC) of visual analogue scale (VAS) scores for postoperative pain at rest in the supine position, rising from the supine to the sitting position, and walking, against time for both treatment groups. RESULTS: There were no significant differences between treatment groups for the AUC of VAS scores for postoperative pain, global verbal pain rating or time to first dose of analgesic medication. CONCLUSIONS: Levobupivacaine exerts a similar anaesthetic and analgesic effect to racemic bupivacaine when infiltrated both intraoperatively and during the early postoperative period for elective inguinal hernia repair.  相似文献   
66.
The question of whether vasodilator nitrates act by releasing prostacyclin is controversial. Since the ability of blood vessels to form prostacyclin changes with age, we have investigated whether this may explain the discrepancies in the literature. It does not, since isosorbide dinitrate or glyceryl trinitrate incubated with rat aorta or vena cava from male Wistar rats had little or no effect on the release of prostacyclin, measured as 6-keto-PGF1 alpha. We confirm that the aorta produces substantially more prostacyclin than the vena cava. The arterial production of prostacyclin was greater in rats weighing 350-400 g than in those weighing 116-152 g, but the production by the veins was similar in both groups.  相似文献   
67.
The neck is not a common area for a skin cancer to occur. However, when it does occur and extends deeply, careful extirpation is necessary so that vital structures will be identified and, if possible, preserved. The Mohs surgeon can most accurately determine the true extent of malignancies in this area; the head and neck surgeon can best identify and protect important anatomic structures. Together both physicians can achieve the best chance of cure and lessen the complication rate for patients with selected invasive cutaneous tumors of the neck. Future collaborative efforts will undoubtedly be directed toward complete extirpation of deeper tumors of the neck, especially those of the pharynx, hypopharynx, and trachea.  相似文献   
68.
69.
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.  相似文献   
70.
A controlled randomized clinical trial was undertaken to assess the ability of combined non-specific and specific immunotherapy to alter the disease-free interval and overall survival of patients with Stage B or C large bowel cancer. The immunotherapy consisted of a 2 year programme of vaccinations with BCG and neuraminidase-treated autologous tumour cells. Three hundred and one patients entered the trial. At 5 years of follow-up there is no evidence that this form of immunotherapy can alter either the disease-free interval or survival in this group of patients.  相似文献   
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