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991.
992.
Whipple's disease is a multisystem bacterial disease usually characterized by malabsorption, diarrhea and polyarthritis. Ocular manifestations include uveitis, vitreitis, retinis, myositis, papilledema and optic atrophy. We report a case of a chronic bilateral vitreitis in a 63 year-old man who had been treated for a Whipple's disease with gastrointestinal involvement 30 years before. The jejunal biopsy was negative but the polymerase-chain-reaction (PCR) revealed the presence of Trophyrema Whippelii in the vitreous prelevement of both eye. This new, original strategy of PCR is specific and more sensitive than histological diagnosis. 相似文献
993.
AM Yip MC Gorman K Stadnyk WG Mills KM MacPherson K Rockwood 《Canadian Metallurgical Quarterly》1998,38(6):735-742
The traditional anion gap [AG = Na-Cl-(total CO2)] mean value of 12 mEq/L was established during the 1970s with analyzer methods that are no longer used widely. No studies have systematically compared mean AG values from analyzers in current use. We used data from healthy subjects obtained from 27 clinical laboratories, 5 manufacturers, and 8 publications to compute mean AG values from 1970s analyzers and 8 current analyzers. We also compared mean AG values by evaluating Na, Cl, and total CO2 data from the College of American Pathologists Chemistry Surveys (1990-1996). Data from healthy subjects showed that overall mean AG values of the 9 analyzers ranged from 5.9 to 12.4 mEq/L. The pooled (i.e., average) AG SD was 2.3 mEq/L. We then used the data of the Surveys and the mean value from 1 analyzer to compute predicted mean values for the other 7 current analyzers. Almost all mean AG values predicted from the Surveys agreed (within 1.5 mEq/L) with mean values from healthy subjects. These results show that mean values of analyzers vary widely, indicating that analytic bias strongly influences the AG. The results should be a useful guide for the AG measurements that can be expected from different analyzers. 相似文献
994.
CF Lau PK Hui KL Mak AM Wong KS Yee CK Loo KM Lam 《Canadian Metallurgical Quarterly》1998,93(12):2559-2564
Currently, upper gastrointestinal endoscopies are frequently performed for patients with various gastrointestinal symptoms. From time to time, lumps and bumps in the stomach are encountered on endoscopy. Four cases of gastric polypoid lesions are presented. The classification, differentiation, and management approach to these lesions are discussed. Although there is consensus that all gastric adenomatous polyps should be removed, as should gastric hyperplastic polyps that are symptomatic and/or bear dysplastic foci on forceps biopsy, controversy still exists over the management of asymptomatic gastric hyperplastic polyps that do not bear any dysplastic focus on forceps biopsies. Endoscopic ultrasonography (EUS) has a promising role in the evaluation of gastric submucosal polypoid lesions. 相似文献
995.
A Martinez D Sun PB Billings KM Swiderek KF Sullivan SO Hoch 《Canadian Metallurgical Quarterly》1998,11(6):611-619
Previous studies have shown that administration of gamma-hydroxybutyric acid (GHBA) or the GABA(B) receptor agonist baclofen are associated with a decrease in firing rate, a regularisation of firing pattern and a decrease in burst activity of midbrain dopamine (DA) neurons in the substantia nigra (SN). In the present study we compared the ability of the novel GABA(B) receptor antagonist SCH 50911 and the selective antagonist of GHBA binding sites, NCS-382, to antagonise the effects of baclofen or GHBA, respectively, on the neuronal activity of DA neurons in anaesthetised rats. SCH 50911 (75 mg/kg, i.v.) was found to antagonise the decrease in firing rate, the regularisation of firing rhythm and the decrease of burst activity in DA cells, induced by baclofen (1-32 mg/kg, i.v.) or GHBA (12.5-1600 mg/kg, i.v.). NCS-382 (100 mg/kg, i.v.) did not affect the baclofen-induced changes in neuronal activity. Neither was the drug able to influence the GHBA-induced alterations in firing rate or in burst activity, although NCS-382 to some extent antagonised the regularisation of the firing pattern observed following low doses of GHBA (< or =100 mg/kg). The results of the present study give further support for the notion that the GHBA-induced changes in neuronal activity of nigral dopamine neurons are mediated by stimulation of GABA(B) receptors. 相似文献
996.
SG Cho YM Park H Moon KM Kim SS Bae GB Kim HS Cho CC Kim KS Lee 《Canadian Metallurgical Quarterly》1998,13(6):685-688
Colony-stimulating factors (CSFs) are commonly used for the treatment of neutropenia following chemotherapy and for the mobilization of peripheral blood stem cells (PBSC). We recently experienced a rare case of a new onset of psoriasiform eruption by GM-CSF (granulocyte-macrophage colony-stimulating factor) which was exacerbated by G-CSF (granulocyte colony-stimulating factor) in a patient with breast cancer. A 36-year-old woman had received neoadjuvant chemotherapy (cyclophosphamide, epirubicin and 5-fluorouracil), modified radical mastectomy and adjuvant chemotherapy with paclitaxel and mitoxantrone followed by GM-CSF administration for the treatment of locally advanced breast cancer. She had developed a psoriatic skin lesion on face and both upper arms during leukocyte recovery in spite of no previous history of psoriasis. Next, the chemotherapy course was complicated by a flare of mild psoriatic skin lesion, although CSF was changed into G-CSF due to GM-CSF-associated psoriasis. Subsequently, she had had high-dose chemotherapy and autologous peripheral blood stem cell transplantation for consolidation therapy. GM-CSF was administered for the mobilization of PBSC and post-transplant period, but psoriatic skin lesion did not appear. During 6 months after PBSCT, psoriasiform eruption did not appear. 相似文献
997.
Previous studies have implicated oxytocin (OT) in the control of surge-type PRL secretion in the pregnant and pseudopregnant rat. The present studies examined the relationship between mating-induced activation of OT neurons in the paraventricular (PVN), supraoptic (SON), and anterior commissural (ACN) nuclei and PRL secretion. Activity within OTergic neurons, as measured by increased c-fos expression, was examined immediately and 5 days following mating in ovariectomized, estrogen-plus-progesterone-treated rats at the time when nocturnal PRL surges are expressed (0600 h) and at an intersurge time (2400 h). Females received fifteen intromissions (15I), 15 mounts-without-intromission (MO), or no stimulation (homecage, HC) from a sexually experienced male. Receipt of 15I at 0600 h induced significantly higher numbers of OT immunoreactive (OT-IR) cells and FOS/OT-IR double-labeled cells in the parvocellular division of the PVN (PVNparv) and in the SON than did 15I at 2400 h. Numbers of OT-IR and FOS/OT-IR cells in the ACN and in the magnocellular compartment of the PVN (PVNmag) were not influenced by mating at either time. In contrast, acute PRL secretion induced within 5-30 min by 15I was not influenced by whether mating occurred at 1800 h (diurnal surge), 2400 h, or 0600 h, nor were plasma OT levels elevated during the 1 h following 15I or MO at these times. Examination of FOS-IR cells throughout the hypothalamus across the two times of day revealed previously unreported differences between 15I and control MO treatments in the PVN, SON, and the ventrolateral part of the arcuate nucleus (ARCvl). On day 5 post mating, numbers of OT-IR and FOS/OT-IR cells in the PVN, SON, and ACN were very low and were similar between 0600 h and 2400 h and between females that showed (15I) or did not show (MO) mating-induced PRL surges characteristic of pregnancy. The results of these studies demonstrate that intromissive but not mounts-only stimulation from males induces a rapid increase in OT-IR staining and OT neuron activation in the PVNparv and the SON. These mating-induced responses in OT neurons occurred within 1 h after mating only at 0600 h, suggesting a diurnal fluctuation in sensitivity to intromissive stimulation. Changes in OTergic function were not seen in response to mating at other times of day, nor at the time of the nocturnal PRL surge 5 days after mating. We conclude that OT activity induced by mating does not act to stimulate PRL secretion directly, but may be involved in the process(es) by which genitosensory stimulation initiates surge-type PRL secretion. 相似文献
998.
999.
SR Leadley KM Shakesheff MC Davies J Heller NM Franson AJ Paul AM Brown JF Watts 《Canadian Metallurgical Quarterly》1998,19(15):1353-1360
Due to poly(orthoesters) being susceptible to acid catalysed hydrolysis, these polymers have attracted considerable interest for the controlled delivery of therapeutic agents within biodegradable matrices. The pH-sensitivity of the poly (orthoesters) has lead to several drug delivery systems being developed, whose rate of drug release is predominantly controlled by the rate of polymer hydrolysis. This study reports on the use of X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and atomic force microscopy (AFM) in a multitechnique approach to probe the effect of acid catalysed hydrolysis at the interface of poly(orthoesters). The molecular specificity of SIMS was successfully employed, suggesting that the preferred mechanism for hydrolysis was via the cleavage of an exocyclic alkoxy bond in the 3,9,-diethylidene-2,4,8,10-tetraoxaspiro [5,5] undecane(DETOSU) unit. The resulting change in the surface chemical structure of the partially hydrolysed poly(orthoester) is such that it was not detectable by XPS analysis. Images acquired from an in situ AFM study of the hydrolysis ofa poly(orthoester), showed changes in the surface morphology, seen as the formation of pits, and an overall thinning of the polymer film. The use of SIMS, XPS and AFM has enabled changes in surface chemistry to be compared with changes in surface morphology. These complementary data, on the behaviour of the polymer during degradation have important implications for the further design of novel biodegradable materials. 相似文献
1000.
NS Kleiman AM Lincoff DJ Kereiakes DP Miller FV Aguirre KM Anderson HF Weisman RM Califf EJ Topol 《Canadian Metallurgical Quarterly》1998,97(19):1912-1920
BACKGROUND: After angioplasty, major complications and ischemic events occur more frequently in diabetic than nondiabetic patients. To determine whether treatment with abciximab is effective in reducing these events in diabetics, we analyzed characteristics and outcomes of diabetic patients enrolled in a large multicenter study (EPILOG). METHODS AND RESULTS: Of 2792 patients enrolled, 638 (23%) were diabetic. Diabetic patients were older, shorter, and heavier; more likely to be female and have three-vessel disease, prior coronary artery bypass graft surgery, a history of hypertension, or a recent myocardial infarction; and less likely to be current smokers than their nondiabetic counterparts. During hospitalization, death, myocardial infarction, or urgent revascularization occurred in 7.1% of diabetics and 7.5% of nondiabetics. By 6 months, the composite of death and myocardial infarction had occurred in 8.8% of diabetic patients and 7.4% of nondiabetics, whereas death, myocardial infarction, or revascularization had occurred in 27.2% and 22.6%, respectively. Abciximab treatment reduced death or myocardial infarction among diabetic and nondiabetic patients (hazard ratios, 0.28 [95% confidence interval (CI), 0.13 to 0.57] and 0.47 [95% CI, 0.33 to 0.70] at 30 days for diabetics and nondiabetics, respectively, and 0.36 [95% CI, 0.21 to 0.61] and 0.60 [95% CI, 0.44 to 0.82] at 6 months for diabetics and nondiabetics, respectively). Abciximab reduced target vessel revascularization among nondiabetic patients (hazard ratio, 0.78 [95% CI, 0.63 to 0.96]) but not among diabetics (hazard ratio, 1.4 [95% CI, 0.94 to 2.08]). When standard- and low-dose heparin adjuncts were compared, diabetics receiving abciximab with standard-dose heparin had marginally greater reductions in the composite of death and myocardial infarction and in target vessel revascularization than diabetics assigned to abciximab with low-dose heparin. CONCLUSIONS: Abciximab treatment in diabetic patients led to a reduction in the composite of death and myocardial infarction, which was at least as great as that seen in nondiabetic patients. However, target vessel revascularization was reduced in nondiabetic but not diabetic patients. This effect may be associated in part with lower doses of heparin. These differences may be related to differences in the platelet and coagulation systems between diabetics and nondiabetics, the greater extent of coronary artery disease in diabetics, or patient selection and management factors. 相似文献