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41.
The effect of some anesthetic drugs on intraocular pressure (IOP) was studied in 120 normal healthy patients undergoing non-ophthalmic surgical procedures. IOP rose significantly following the injection of succinylcholine (SCh) alone, or when such injection had been preceded by a pretreatment with a "self-taming" dose of SCh or d-tubocurarine (d-Tc). Though the rise in IOP after diazepam pretreatment was significant, the magnitude was lower than that observed in the groups pretreated with the other two agents. Halothane brought the IOP down faster and lower than ether. SCh is unsafe for intubation for the administration of general anesthesia in cases involving penetrating ocular injuries. It can, however, be used safely for routine ophthalmic surgery, providing that 8 minutes are allowed to elapse between injection and corneal or scleral incision. Halothane is preferred to ether, since the former lowers IOP faster and in a greater amount than the latter.  相似文献   
42.
Assay of hexosaminidase A and B enzymes in four cases with developmental regression and cherry red spot on fundus examination confirmed that three cases had Tay-Sachs disease, and one case had Sandhoff disease. Prenatal diagnosis was carried out by hexosaminidase enzyme assay in amniotic fluid and cells in one family, and chorionic villus sample in the second family. The fetus was diagnosed to be unaffected in one, and affected in the other family. Assay of hexosaminidase A and B is useful for specific diagnosis of GM2 gangliosidosis, and for prenatal diagnosis to reduce the burden of these disorders.  相似文献   
43.
Kaur C  Ling EA 《Neuroscience letters》1999,262(3):183-186
This study was aimed to ascertain the effects of hypoxia on regulation of iron in the brain of newborn rats. At 3 h and 1 day after hypoxic exposure transferrin receptor expression as detected immunohistochemically with the antibody OX-26, and the iron content as shown by Perls' staining of amoeboid microglial cells was markedly increased. The induced changes, however, were not evident at 10 min and in longer surviving rats killed at 3 and 7 days. It is suggested that the upregulation of transferrin receptor expression coupled with iron uptake by amoeboid microglial cells in the periventricular regions is a protective mechanism to facilitate the sequestration of excess iron that may have been released either from the iron-rich oligodendrocytes, or accumulated due to a disruption of its normal transportation following the hypoxic insult. This would help protect the brain from harmful effects of iron.  相似文献   
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45.
Traditionally, it has been accepted that chronic suppurative Otitis media is associated with a breakdown in meekanical conduction of sound leading to conductive hearing loss, On;the contrary, there are two schools of thought when it come, to the issue of cpchlear involvement leading to sensorineural hearing loss (SNIIL) in chronic suppura the Otitis media. The present study was undertaken to find out whether a sensorineural component exists in hearing loss associated with chronic suppurative otitis media, A sample of 100 patients of unilateral chronic suppurative otitis media was selected for the Study and their bone conduction thresholds Mere analyzed in relation to the duration of disease using audiometric data. A 24 per cent incidence of sensoineural hearing loss was found in this series, garticularly involving the higher frequencies. Moreover, the incidence of sensorineural hearing loss progressively increased with the increase in duration of chonic suppurative Ouns meadia  相似文献   
46.
PURPOSE: The purpose of this study was to investigate the antiangiogenic properties of 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG; NSC707545), a water-soluble benzoquinone ansamycin. EXPERIMENTAL DESIGN: The activity of 17-DMAG, in vivo, was evaluated for inhibition of fibroblast growth factor (FGF)-2-induced angiogenesis in s.c. implanted Matrigel in mice. In vitro, the activity of 17-DMAG on endothelial cells (human umbilical vein endothelial cells; HUVEC) was tested in FGF-2; and vascular endothelial growth factor (VEGF)-induced proliferation and apoptosis, motility, and extracellular matrix invasion; and on the alignment of capillary like structures in Matrigel. The protein level of heat shock protein (Hsp)90 and client proteins was examined by Western blot in FGF-2 and VEGF-stimulated HUVEC. RESULTS: Daily oral administration of 17-DMAG affected the angiogenic response in Matrigel in a dose-dependent manner. The hemoglobin content in the Matrigel implants was significantly inhibited, and the histological analysis confirmed a decrease of CD31(+) endothelial cells and of structures organized in cord and erythrocyte-containing vessels. In vitro, the compound inhibited dose-dependently the migration and the extracellular matrix-invasiveness of HUVEC and their capacity to form capillary like structures in Matrigel. 17-DMAG treatment also inhibited FGF-2 and VEGF-induced HUVEC proliferation and resulted in apoptosis. Accordingly, the expression of Hsp90 direct client proteins (pAkt and c-Raf-1) or their downstream substrates including pERK was also affected. 17-DMAG consistently increased the expression of Hsp70. Throughout the study similar results were obtained with 17-allylamino-17-demethoxygeldanamycin (17-AAG; NSC330507), the analog compound currently undergoing clinical trials. CONCLUSIONS: We show that the Hsp90 targeting agents 17-DMAG and 17-AAG inhibit angiogenesis. The strong effects on endothelial cell functions, in vitro, indicate that the antiangiogenic activity of 17-DMAG/17-AAG could also be due to a direct effect on endothelial cells. The oral bioavailability of 17-DMAG might be of advantage in investigating the potential of this compound in clinical trials with antiangiogenic as well as antiproliferative endpoints.  相似文献   
47.
The purpose is to determine breast cancer risk factors and correlates of mammographic parenchymal patterns among Alaska Native women. A retrospective review was performed of mammograms and mammogram records among 528 sequential screening mammogram examinations performed in Anchorage, Alaska. Mammogram density was classified by American College of Radiology (Breast Imaging Reporting and Data System) density patterns 1-4 (fat-->dense) and by percent density. Clinical data, including risk factors, ethnic group (Indian, Aleut, or Eskimo), and smoking status were obtained. Results were analyzed by univariate and multivariate analyses. Of 528 women, 164 were Indian, 155 were Aleut, and 209 were Eskimo. Mean age at first birth was lower and parity higher compared with published data in white women. Breast cancer risk factors were similar across ethnic groups. In multivariate analysis, patient age, parity, hormone replacement therapy, hysterectomy, and history of biopsy were associated, and smoking was not associated with density scores. Aleut and Indian women were less likely to have high-density mammograms than were Eskimo women (P = 0.0448). No significant differences were found between ethnic group for conventional breast cancer risk factors. Mammogram density was associated with age at screening, parity, hormone replacement therapy, hysterectomy, history of biopsy, and ethnicity but not smoking status. Eskimo women had higher mammogram density than Aleuts or Indians.  相似文献   
48.
PURPOSE: We examined the role of paclitaxel and cisplatin as first line therapy for metastatic urothelial cancer. MATERIALS AND METHODS: A total of 34 patients were enrolled in this study, and all were eligible for treatment and assessable for response. Patients received 135 mg./m.2 paclitaxel intravenously for 3 hours followed by 70 mg./m.2 cisplatin for 2 hours every 3 weeks to a maximum of 6 cycles. RESULTS: Of the patients 70% experienced a major response to treatment, which was partial/regression in 38% and complete in 32%. Toxicity was manageable with no episodes of grade 4 leukopenia or thrombocytopenia. Nonhematological toxicities included primarily nausea, anorexia and neuropathy, which rarely were severe. CONCLUSIONS: This regimen of paclitaxel and cisplatin is effective, safe and convenient to administer in an outpatient setting for advanced urothelial cancer.  相似文献   
49.
Tracheoesophageal fistula is a life threatening condition. Patients not managed surgically ultimately die of their disease. Surgical management is the treatment of choice. We present a case of a patient that developed a tracheoesophageal fistula after tracheostomy. Surgical repair was done which failed due to infection. The patient was managed with the help of an esophageal stent and Trichloroacetic Acid cautery. This approach can be used in selected patients, depending upon the size and site of TEE Larger fistulae and those situated lower down e.g. supra carinal cannot be managed by this technique.  相似文献   
50.
Objectives: The present study was designed to evaluate the efficacy of Lactuca sativa (LS) Linn. (Asteraceae) against scopolamine-induced amnesia and to validate its traditional claim as memory enhancer.

Methods: Ethanol extract of fresh LS leaves (LSEE), standardized on the basis of quercetin content, was successively partitioned using various solvents viz., hexane, ethyl acetate, and n-butanol in increasing order of polarity. LSEE (50, 100, and 200?mg/kg) and its various fractions (at a dose equivalent to dose of LSEE exhibiting maximum activity), administered orally for 14 days, were evaluated for their memory enhancing effect against scopolamine-induced (1?mg/kg, i.p.) amnesia in 3–4 months old male Laca mice (n?=?6 in each group). The memory enhancing effect was evaluated using behavioural (elevated plus maze, novel object recognition and Morris water maze tests) and biochemical parameters (acetylcholinesterase activity, malonaldehyde, superoxide dismutase, nitrite, catalase, and reduced gultathione content). The results of the test substances were compared with both scopolamine and donepezil that was used as a standard memory enhancer and acetylcholinesterase inhibitor.

Results: Scopolamine elicit marked deterioration of memory and alteration in biochemical parameters in comparison to the control group. LSEE and its n-butanol and aqueous fractions significantly (P?n-butanol fraction (15?mg/kg) exhibited maximum anti-amnesic effect among various tested dose levels.

Discussion: The results exhibited that LS prophylaxis attenuated scopolamine-induced memory impairment through its acetylcholinesterase inhibitory and antioxidant activity validating its traditional claim.  相似文献   
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