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21.
T. P. Poon M. Behbahani I. Matoso B. Kim 《Journal of the National Medical Association》1994,86(7):550-552
A pineal mass in a patient with acquired immunodeficiency syndrome (AIDS) is reported. Computed tomography (CT) scan revealed a nodular mass in the pineal region with foci of calcification and obstruction of the aqueduct mimicking a pineal tumor. At autopsy, the brain revealed a well-circumscribed lesion with central necrosis in the pineal region suggestive of toxoplasma and involving the periaqueductal area. Susceptibility of a patient with AIDS to opportunistic infections should be considered. 相似文献
22.
D. A. Stewart D. Guo J. A. Sutherland B. A. Ruether A. R. Jones M.-C. Poon C. deMetz J. Klassen A. Chaudhry C. B. Brown J. A. Russell 《Annals of oncology》1997,8(12):1277-1279
Background: Few data are available on the cost, safety, and long-termefficacy of single agent high-dose melphalan (HDM) followed by autologousbone marrow (ABMT) or blood stem cell (ABSCT) transplantation in the salvagetherapy of Hodgkins disease (HD).Patients and methods: From February 1981 to September 1996, 23 patientswith relapsed (n = 15) or refractory (n = 8) HD received salvage therapywith HDM 140–200 mg/m2 followed by non-cryopreservedABMT (n = 18) or cryopreserved ABSCT (n = 5). The cost of HDM/ABSCT in 1996,from initial consultation until transfer back to referring physician, wasdetermined and compared to the estimated costs of two multi-agent regimenscommonly used for HD.Results: HDM was well tolerated with no early transplant-relatedmortality. The five-year overall and progression-free survival rates were52% and 50%, respectively. The average total cost in Canadianfunds of HDM/ABSCT in 1996 was $34,400/patient. This cost wasestimated to be $4,700–6,800 cheaper per patient than themulti-agent high-dose regimens.Conclusion: These data suggest that HDM is safe, feasible, active, andreasonably inexpensive salvage therapy for patients with relapsed/refractoryHD. 相似文献
23.
Parasitic nematode worms which produce filariasis in humans place approximately one billion people at risk in more than 75 countries. More than 100 million people are infected with these diseases and are recognized as being of significant military importance. During World War II, filariasis was among the leading causes of medical evacuation from the entire South Pacific area. Agents available to treat the diseases exhibit significant toxicity. Better drugs are urgently needed. Data are reported from work using a Mongolian jird animal model on a new class of potential drugs, thiosemicarbazones. These compounds exhibit activity against the parasites which cause both lymphatic filariasis and the "onchocerciasis type" of the disease. 相似文献
24.
25.
BACKGROUND: A study was performed to determine the type and frequency of ocular injuries in patients with major trauma. METHODS: All patients with ocular and adnexal injuries (n = 178) among 1,119 patients admitted with major trauma (Injury Severity Score >15) to the Royal Prince Alfred Hospital from July 1990 to December 1997 were analyzed. RESULTS: Sixteen percent of the major trauma cohort had ocular or orbital trauma. Fifty-five percent of patients with injuries involving the face had ocular or orbital injuries. A range of ocular injuries was seen. Analysis of the major trauma cohort showed that motor vehicle drivers, orbital and base of skull fractures, eyelid lacerations, and superficial eye injuries were strongly associated with vision-threatening injury. CONCLUSION: Patients with major trauma and facial injuries have a high risk of vision-threatening injury. Patients with orbital fractures, base of skull fracture, eyelid lacerations, and superficial eye injuries should be assessed by an ophthalmologist as part of the early management of their trauma to determine whether an ocular injury is present. 相似文献
26.
Tissue factor expression correlates with tumor angiogenesis and invasiveness in human hepatocellular carcinoma. 总被引:23,自引:0,他引:23
Ronnie Tung-Ping Poon Cecilia Pik-Yuk Lau Joanna Wen-Ying Ho Wan-Ching Yu Sheung-Tat Fan John Wong 《Clinical cancer research》2003,9(14):5339-5345
PURPOSE: Recent studies have shown that tissue factor (TF) may be involved in tumor angiogenesis and metastasis. The role of TF in hepatocellular carcinoma (HCC) was unknown. This study evaluated whether TF expression correlates with microvessel density (MVD), vascular endothelial growth factor (VEGF) expression, tumor invasiveness, and prognosis in human HCC. EXPERIMENTAL DESIGN: Tissue samples were obtained from 58 specimens of resected HCC. Immunohistochemical expression of TF was examined, and tumor MVD was evaluated using CD34 as the endothelial marker. TF and VEGF protein levels in the tumor cytosol were quantified by ELISA. Clinicopathologic and follow-up data of patients were prospectively collected. RESULTS: The immunohistochemical expression of TF in the tumors correlated significantly with tumor MVD (P = 0.002). The median cytosolic TF protein level in the tumors was 720 pg/mg total protein (range, 67-2406 pg/mg total protein). A significant positive correlation was found between TF and VEGF levels in the tumor cytosol (r = 0.475, P < 0.001). High tumor cytosolic TF level was associated with venous invasion (P = 0.004), microsatellite nodules (P = 0.024), unencapsulated tumor (P = 0.007), and advanced tumor stage (P = 0.010). A higher than median tumor cytosolic TF level was an independent predictor of poor survival (risk ratio, 1.836; 95% confidence interval 1.130-5.312, P = 0.023). CONCLUSIONS: This study shows that TF is related to tumor angiogenesis and invasiveness in HCC. Evaluation of tumor TF expression may be useful as a prognostic indicator in patients with HCC. 相似文献
27.
AIMS: To study the effect of prone and supine sleep on infant behaviour, peripheral skin temperature, and cardiorespiratory parameters to aid understanding of why prone sleeping is associated with an increased risk of sudden infant death syndrome. METHODS: Of 33 enrolled infants, 32 were studied at 2.5 and 28 at 5 months of age. A computer aided multichannel system was used for polysomnographic recordings. Behaviour was charted separately. RESULTS: Prone REM (active) sleep was associated with lower frequencies of short arousals, body movements and sighs, and a shorter duration of apnoeas than supine REM sleep at both ages. At 2.5 months there were less frequent episodes of periodic breathing during prone sleep in non-REM (quiet) and REM sleep. Heart rate and peripheral skin temperature were higher in the prone position during both sleep states at both ages. CONCLUSIONS: The observation of decreased variation in behaviour and respiratory pattern, increased heart rate, and increased peripheral skin temperature during prone compared with supine sleep may indicate that young infants are less able to maintain adequate respiratory and metabolic homoeostasis during prone sleep. 相似文献
28.
Janet Martin Stephen M. Stribbling Grace K. Poon Richard H. J. Begent Mark Napier Surinder K. Sharma C. J. Springer 《Cancer chemotherapy and pharmacology》1997,40(3):189-201
Antibody-directed enzyme prodrug therapy (ADEPT) was administered to ten patients in a phase I clinical trial. The aim was
to measure plasma levels of the prodrug 4-[(2-chloroethyl)(2-mesyloxyethyl) amino] benzoyl-l-glutamic acid (CMDA) and the bifunctional alkylating drug (CJS11) released from it by the action of tumour-localised carboxypeptidase
G2 (CPG2) enzyme. New techniques were developed to extract the prodrug and drug from plasma by solid-phase adsorbtion and
elution and to measure CPG2 activity in plasma and tissue. All extracts were analysed by high-performance liquid chromatography
(HPLC) and liquid chromatography-mass spectrometry (LC-MS). CPG2 activity was found in metastatic tumour biopsies but not
in normal tissue, indicating that localisation had been successful. The clearing agent SB43-gal, given at 46.5 mg/m2, achieved the aim of clearing non-tumour-localised enzyme in the circulation, indicating that conversion of prodrug to drug
could take place only at the site of localised conjugate. Plasma prodrug did not always remain above its required threshold
of 3 μM for the “therapeutic window” of 120 min after dosing, but the presence of residual prodrug after the first administration
of each day indicated that this could be achieved during the remaining four doses over the following 8 h. Despite considerable
inter-patient prodrug plasma concentration variability, the elimination half-life of the prodrug was remarkably reproducible
at 18 ± 8 min. Rapid appearance of the drug in plasma indicated that successful conversion from the prodrug had taken place,
but also undesirable leakback from the site of localisation into the bloodstream. However, drug plasma levels fell rapidly
by at least 50% at between 10 and 60 min with a half-life of 36 ± 14 min. Analysis of the plasma extracts by LC/MS indicated
that this technique might be used to confirm qualitatively the presence of prodrug, drug and their metabolites.
Received: 21 July 1996 / Accepted: 20 January 1997 相似文献
29.
This paper describes a PC-based system for simultaneous monitoring of locomotor and sound activities on small rodents. The displacement and location signals of the animal were first determined across consecutive video-frames, followed by marked data reduction to cater for long-term studies. At the same time, sounds generated by the animal were detected and the sound level was recorded as root-mean-square values at 1 s intervals. Preliminary data showed that such a multi-parametric monitor system could provide comprehensive information on the animal's activity. 相似文献
30.