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101.
David S. K. Lu Shantanu Sinha John Lucas Keyvan Farahani Robert Lufkin Klaus Lewin 《Journal of magnetic resonance imaging : JMRI》1997,7(2):303-308
The purpose of this study was to test the feasibility of MR-guided percutaneous ethanol ablation of liver tissue on a .2-T open MR scanner. Needles were placed by MR guidance first into an ex vivo sheep liver and then into livers of three anesthetized pigs, and injection of 10 ml of 96% alcohol was performed. T1 fast low-angle shot (FLASH), T2 turbo spin echo (TSE), and T1 spin echo (SE) images were obtained after incremental volumes of injection. In one pig, simultaneous injection of saline into normal liver was also performed with subsequent pathological correlation. Ethanol-infiltrated liver was hypointense to liver on all sequences, whereas saline caused no tissue signal changes on T1 SE and either isointense or hyperintense changes on T2 TSE images. Pathological examination confirmed ethanol-induced acute liver changes as compared with the control. MR guidance of needle placement and monitoring of ethanol effects on liver tissue is feasible. This may have implications for potential MR-guided hepatic tumor ablation. 相似文献
102.
Patrick J. Bindels Dieke K. Mulder-Folkerts Kees Boer Maarten F. Schutte Wouter J. van der Velde Frans J. Wong Anneke J. A. R. van den Hoek Gerard J. van Doornum Roel A. Coutinho 《European journal of epidemiology》1994,10(3):331-338
The objective of the study was to monitor the HIV prevalence in the years 1988–1991 among pregnant women in the Amsterdam region, visitors to an abortion clinic and 3 outpatient infertility clinics. All women attending these clinics were asked to participate in the study on a voluntary basis and were tested with informed consent. The women were questioned about risk-bearing behaviour of themselves and their sexual partner(s). In the period 1988–1991, of the 23,827 eligible pregnant women, 22,165 women participated (93.0%). Twenty-seven women were found to be positive for HIV antibodies (0.12%, 95% CI: 0.08%–0.17%), of whom twenty belonged to a known HIV risk group or had a partner who belonged to one of these groups and 7 women had no known HIV risk. Seventeen of the 27 women had a foreign nationality. The annual HIV prevalence among pregnant women was: 1988: 0.28%; 1989: 0.10%; 1990: 0.10%; 1991: 0.11%. In the years 1990 and 1991, of the 1,128 eligible women visiting the abortion clinic 953 (84.5%) were tested. Eleven women were HIV-seropositive (1.15%, 95% CI: 0.6%–2.0%), of whom 9 were from an AIDS endemic region, 1 woman had a partner from this region and 1 woman had no known HIV risk. Four African women had HIV-2 antibodies. At the 3 outpatient infertility clinics 1 woman was found to be HIV-positive (0.13%; 95% CI: 0.02–0.9). She had no other risk than a partner from an AIDS endemic area. In the Amsterdam region there was a steady and low HIV prevalence (0.1%) among pregnant women through the years 1988–1991. The prevalence in the abortion clinic was ten times higher. The program was able to detect possible high risk groups within the population. Migration and travelling can play an important role in the spread of HIV in the general heterosexual population. 相似文献
103.
Edward H.C. Wong MRCP Thomas W.H. Leung MRCP K.S. Lawrence Wong FRCP 《Journal of neuroimaging》2007,17(1):87-88
We report a 33-year-old man with seronegative arthritis who had an acute infarct at the left lentiform nucleus while taking etoricoxib and thalidomide regularly. Extensive investigations did not find any evidence of large artery atherosclerosis, vasculitis, cardioembolic source or anti-phospholipid antibodies. While it is possible that a short smoking history, hyperlipidemia, and the use of thalidomide could have contributed to the thrombosis of a small penetrator vessel, we postulated that the prolonged use of etoricoxib is another possible contributing factor. 相似文献
104.
Manohar Bance Alfredo Campos Lillian Wong David P Morris Rene van Wijhe 《Otolaryngology--head and neck surgery》2007,137(1):70-73
OBJECTIVES: The transmission of vibrations from the tympanic membrane to the stapes footplate by an ossicular reconstruction prosthesis is affected by the size of the prosthesis head. We sought to determine if augmenting or reducing the head size of prosthesis had a systematic effect on transmission of vibrations to the stapes. STUDY DESIGN: We conducted a fresh cadaveric temporal bone middle ear study. METHODS: The incus was replaced with a prosthesis using a tympanic membrane to stapes head (TASH)-type hydroxyapatite prosthesis in nine fresh cadaveric temporal bones. Three prosthesis head sizes were created: unaltered, reduced, and augmented. Stapes vibrations were measured with a laser Doppler vibrometer in response to acoustic frequency chirps at 90 dB SPL. RESULTS: All three head size prostheses resulted in smaller stapes vibrations than the intact ear. There was no difference in the vibration transmission between the three different head sizes. All prostheses showed a vibration loss of 10 to 15 dB compared to the intact ear. CONCLUSIONS AND SIGNIFICANCE: Within the range of sizes tested, prosthesis head size had little impact on vibration transmission to the stapes footplate. 相似文献
105.
K L Wong 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》1991,9(2):125-129
Seven patients with systemic lupus erythematosus (SLE), persistent thrombocytopenia (TP), in whom it was considered undesirable to institute an increase in steroid or immunosuppressive agents, were treated with danazol. Five patients completed the minimum period of 8 weeks. Two patients showed early response to danazol but were switched over to cyclophosphamide or azathioprine after 4 weeks because of systemic disease. Of the remaining five patients, four had complete responses. In one patient who failed treatment the TP was considered to be related to another drug (ranitidine). Other manifestations of SLE also improved with treatment. Side effects included amenorrhea in one patient, and hypoglycemia and hyponatremia in another. Infections were absent. Danazol can be a useful alternative treatment of lupus TP. 相似文献
106.
Complications associated with maxillary nerve block anaesthesia via the greater palatine canal 总被引:2,自引:0,他引:2
Anthony M. Sved John D. Wong Head Peter Donkor James Horan Leesa Rix Justin Curtin and Russell Vickers 《Australian dental journal》1992,37(5):340-345
This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney. 相似文献
107.
Smooth muscle relaxant effect of dehydroindicolactone 总被引:1,自引:0,他引:1
Dehydroindicolactone, a novel linear furanocoumarin with an 8-substituted side chain carrying a 5-member ring lactone, showed spasmolytic activity in a number of smooth muscle preparations. The spasmolytic activity seems to lie in its ability to block the dihydropyridine-sensitive calcium channel. 相似文献
108.
A chemiluminescence technique (CLT) has been developed which measures the interaction between human monocytes and antibody-coated (opsonized) platelets. This technique has an objective end-point, is simple to perform and is of comparable sensitivity to the platelet suspension immunofluorescence test (PSIFT) when used to detect anti-platelet allo-antibodies. In contrast, only 4/20 sera from patients with clinically diagnosed autoimmune thrombocytopenia were opsonic in the CLT, while 8/20 of these same sera bound IgG to platelets in the PSIFT. Only one serum gave positive results in both tests. 相似文献
109.
4 cases of syringomyelia with type I Arnold Chiari malformation was seen presenting mainly with dissociated sensory loss, weakness of hands and upper motor neurone signs in the lower limbs. The first patient improved with posterior fossa decompression. The second and fourth patient appeared not to have improved after surgery, and the third case refused operation. One patient showed cord atrophy on myelogram presumably due to a collapse of the syrinx. One of the patients was unusual in that the syrinx extended down to segment T11. Magnetic resonance imaging of the posterior fossa and the cervical cord, to date, is the most useful procedure for diagnosis. 相似文献
110.
R C Peffer D J Abraham M A Zemaitis L K Wong J D Alvin 《Drug metabolism and disposition》1987,15(3):305-311
The metabolism of the antisickling agent 3,4-dichlorobenzyloxyacetic acid (3,4-DCBAA) was examined after ip administration to rats. Within 5 days after administration of radiolabeled 3,4-DCBAA, 77.4 +/- 4.6% of the dose was recovered in the urine and only 3.2 +/- 0.5% was recovered in the feces. Metabolites in the urine were isolated and characterized by HPLC, electron impact MS, and LC/MS, and their identities were confirmed by comparing their spectra with those of synthetic standards. Quantitation of these urinary metabolites revealed that the majority of the radioactive dose was excreted as a taurine conjugate (60.1 +/- 4.4%), while lesser amounts were excreted as 3,4-dichlorohippurate, unchanged 3,4-DCBAA, the glycine conjugate of 3,4-DCBAA, and a polar unknown which is believed to be glycolic acid. A pathway involving an initial O-dealkylation at the benzyl carbon of 3,4-DCBAA and proceeding through the glycine conjugation of 3,4-dichlorobenzoic acid has been proposed to explain the formation of 3,4-dichlorohippurate and the polar unknown. The extensive conjugation of 3,4-DCBAA with taurine is an unprecedented observation in rats, which usually utilize glycine for amino acid conjugation reactions. Further studies with 3,4-DCBAA may provide insight into the enzymatic mechanisms of taurine conjugation, which are not well defined at this time. 相似文献