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991.
992.
The effects of monopolar and bipolar diathermy systems were studied in 12 male Sprague-Dawley rats. Fulguration was achieved by application of a standard current (13 W for 1 s) on the foreskin. Tissue damage was assessed by light microscopy. Results suggest that bipolar probe causes less tissue damage than its monopolar counterpart. It has proved to be of value in plastic and paediatric procedures and is recommended for the urologist's armamentarium.  相似文献   
993.
114 patients aged over 75 underwent surgery for aneurysm of the infra-renal abdominal aorta in the University Teaching Hospitals in Nantes and Angers between 1979 and 1988. A retrospective study of these patients was performed to evaluate the immediate and long-term results. The mean age of the patients was 79 (+/- 4) years, the oldest being 94. 70% were men. Half of the patients underwent emergency or semi-emergency surgery (52 cases). Cardiovascular factors (in particular coronary insufficiency in 17% of cases) were the most common risk factors. In all cases grafting after laying open the aneurysm was performed, with an aorto-aortic graft in 32% of patients, an aorto-iliac graft in 37% or an aorto-bifemoral graft in 27% of patients. Combined intestinal revascularisation was performed in 10% of case either involving the inferior mesenteric artery or at least one internal iliac artery; renal revascularisation was performed in 3.5% of cases. 75% of patients underwent simple grafting. The mean duration of hospitalisation was 14 days (+/- 6), including a mean period of 7 days in ICU. 36 patients (31%) died in the first post-operative month. The mortality rate in patients who underwent emergency surgery for a complication of the aneurysm (essentially rupture) was 61% versus 6' for elective surgery. 96% of the patients who survived the first post-operative month were independent at the end of the study or at the time of their death.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Local anesthetics injected retrobulbarly are detectable in the aqueous humor. From 40 patients who received a total dose of 140 mg lidocaine, 15 mg bupivacaine, and 30 mg etidocaine, samples of aqueous humor were taken between 30 and 90 minutes after administration (average 57 minutes). The mean lidocaine concentration was 1.02 micrograms/ml, that of bupivacaine 0.075 micrograms/ml. Etidocaine, used only for facial nerve block in front of the ear, could not be detected in the aqueous humor. All three substances were found in the central venous blood. It therefore appears unlikely that any of them are transported via the blood-aqueous barrier, whether actively or passively. Local anesthetics can inhibit corneal cell proliferation and result in lens opacification when administered into the conjunctival sac. It may be that local anesthetics detected in the aqueous humor have similar effects resulting from contact with the cornea and lens.  相似文献   
995.
The main features of central 5-HT1 receptors   总被引:1,自引:0,他引:1  
The 5-HT1 receptor family comprises five different pharmacologic subtypes, designated 5-HT1A, 5-HT1B, 5-HT1C, 5-HT1D, and 5-HT1E, whose common property is to bind 5-HT with nanomolar affinity. Recent investigations with molecular biology approaches led to the cloning and sequencing of 5-HT1A receptors in the rat and in the human, and of the 5-HT1C receptor in the rat. Although the 5-HT1A and 5-HT1C protein binding subunits exhibit the same structure with seven hydrophobic transmembrane domains, an extracellular N terminal and an intracellular C tail, their respective amino-acid sequences are markedly different. Indeed, a higher degree of sequence homology is found between the 5-HT1C and 5-HT2 receptors than between the former and 5-HT1A receptors, suggesting that the 5-HT1C subtype in fact belongs to the 5-HT2 class of central 5-HT receptors. All other 5-HT1 receptor subtypes are negatively coupled to adenylyl cyclase, whereas the 5-HT1C subtype, like 5-HT2 receptors, is positively coupled to phospholipase C. The respective regional distributions and regulatory properties, as well as pending questions regarding the ultrastructural localization, synthesis, mutual interactions, and axonal flow of 5-HT1 receptor subtypes, are also discussed.  相似文献   
996.
The inequitable distribution of medical services in Australia means that many rural dwellers do not have easy access to ophthalmic care. In regions with no medical personnel, appropriately trained rural health workers may provide ophthalmic assessment, primary treatment, and, in some circumstances, definitive care. In areas with overburdened services, these rural health workers may augment facilities already established. In an attempt to improve the accessibility and quality of ophthalmic services available to presently disadvantaged rural inhabitants, the aims, curriculum, and structure of a 'Basic Ophthalmic Assessment and Care Workshop', for the transfer of knowledge and skills to such rural health workers, is presented.  相似文献   
997.
FD & C Blue No. 1 was fed to Charles River CD rats and CD-1 mice as a dietary admixture in lifetime toxicity/carcinogenicity studies. The rat study was conducted with an in utero phase in which the compound was administered to the F0 generation rats (60/sex/group) at dietary concentrations of 0.0%, 0.0%, 0.1%, 1.0% or 2.0%. After randomly selecting the F1 animals, the lifetime phase was initiated at the same levels with 70 rats/sex/group, including two control groups. The maximum exposure times were 116 and 111 wk for males and females, respectively. The no-observed-adverse-effect levels are dietary concentrations of 2.0% for males (1072 mg/kg body weight/day), and 1.0% for females (631 mg/kg/day) based on a 15.0% decrease in terminal body weight and decreased survival in the high-dose females compared with the combined control groups. Charles River CD-1 mice (60/sex/group) were fed FD & C Blue No. 1 as a dietary admixture at levels of 0.0%, 0.0%, 0.5%, 1.5% or 5.0% in a lifetime toxicity/carcinogenicity study. The maximum exposure time was 104 wk for both males and females. No consistent, significant compound-related adverse effects were noted. The no-observed-adverse-effect level established in this study is a dietary concentration of 5.0% (7354 mg/kg/day and 8966 mg/kg/day for male and female mice, respectively.  相似文献   
998.
This study retrospectively analyzes the CT findings of 50 patients with spontaneous intracerebral haematomas and correlates them with the clinical condition at admission and the outcome. The volume of the haematoma was well correlated with the outcome and was a very useful indicator for surgery. In patients with haematoma volume lower than 25 ml and above 80 ml there was no indication for surgery; in patients with haematoma volume between 25 and 50 ml the operation does not significantly modify the survival rate, but favours a more rapid and complete recovery of the neurological deficits, whereas a haematoma volume between 50 and 80 ml favours the rate of survival.  相似文献   
999.
Thirty-five patients who had thirty-seven mucous cysts excised from the distal interphalangeal joints were reviewed not less than one year later. Seven out of 25 which had been treated by simple excision recurred, whereas only one out of twelve treated by excision and skin closure with a rotation flap recurred.  相似文献   
1000.
Hydrocephalus and cavernoma of the cauda equina   总被引:1,自引:0,他引:1  
F Ramos  B de Toffol  B Aesch  M Jan 《Neurosurgery》1990,27(1):139-142
The association of a tumor of the cauda equina and hydrocephalus is unusual. We report a case of hydrocephalus with normal pressure associated with an equally rare affliction, a cavernous angioma of the cauda equina, which regressed after surgical ablation. The physiological mechanism involved is discussed.  相似文献   
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