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排序方式: 共有3101条查询结果,搜索用时 46 毫秒
221.
Tang WK Chan SS Chiu HF Wong KS Kwok TC Mok V Ungvari GS 《International journal of geriatric psychiatry》2003,18(8):706-710
BACKGROUND: Little is known about the performance of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) in the screening of post-stroke dementia (PSDE). METHODS: At 3 months after the index stroke, a research assistant administered the IQCODE to relatives of 189 Chinese patients with acute stroke who were consecutively admitted to a general hospital. A psychiatrist, who was blind to the IQCODE scores, interviewed all 189 patients and made DSM-IV diagnosis of dementia, which served as the benchmark for judging the performance of IQCODE in screening PSDE. RESULTS: The optimal cut-off point of IQCODE was 3.40. The sensitivity, specificity, and positive and negative predictive values of IQCODE, and the area under the receiver operating characteristic curve, were 88%, 75%, 33%, 98%, and 0.88, respectively. CONCLUSIONS: When used as a sole instrument, IQCODE does not appear to be useful in screening PSDE in Chinese elderly. 相似文献
222.
Hartsel SC Baas B Bauer E Foree LT Kindt K Preis H Scott A Kwong EH Ramaswamy M Wasan KM 《Journal of pharmaceutical sciences》2001,90(2):124-133
The purpose of the present study was to examine the influence of heat-induced superaggregation of Amphotericin B (AmB) in the Fungizone (FZ) formulation on its interaction with human serum components and relate this to reduced toxicity. Whole serum distribution studies showed that a significantly lower percentage of AmB from HFZ was recovered in the high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglyceride-rich lipoprotein (TRL) fractions and a greater percentage recovered in the lipoprotein-deficient plasma (LPDP), though the majority of both preparations were recovered in LPDP. Circular dichroism (CD) and difference absorption spectroscopy were used to determine the stability of FZ and heat-treated FZ (HFZ) in the presence of HDL, LDL, serum, and albumin. The CD studies indicate that the "core" aggregate of HFZ is more stable in the presence of HDL and LDL, whereas the FZ is less stable and more dynamic with the core aggregate dissociating to a greater extent in the presence of either purified lipoprotein. Absorption studies with whole serum and purified albumin suggest that FZ aggregates are far less stable in the presence of albumin than HFZ and that interaction with serum albumin is a dominant feature for both drug preparations. HFZ also has a different effect on the cytokine response in vitro. Studies using THP-1 human monocytes show that HFZ provokes a smaller release of tumor necrosis factor (TNF)-alpha than FZ. This cytokine may be associated with the unpleasant side effects of AmB. These findings suggest that heat-induced superaggregation of AmB alters its interaction with HDL, LDL, serum proteins, and monocytes, and these findings may be important in explaining the reduced toxicity of the superaggregated form of AmB. 相似文献
223.
Primary CD56 positive lymphomas of the gastrointestinal tract 总被引:2,自引:0,他引:2
BACKGROUND: Primary CD56 positive lymphoma of the gastrointestinal (GI) tract is rare. Genotypically, these tumors can be classified into natural killer (NK)-like T-cell lymphoma or NK cell lymphoma by the presence or absence of T-cell receptor (TCR) gene rearrangement. However, they have a considerable degree of morphologic and immunophenotypic overlap, making a definitive diagnosis difficult. METHODS: The clinicopathologic features of three patients with primary CD56 positive lymphoma of the small and large bowel are presented. This is followed by a review of the English literature from 1966 to the present. RESULTS: All patients had CD56 positive/CD3epsilon positive disease on paraffin section. Two patients were positive for Epstein-Barr virus-encoded early nuclear RNAs (EBER) according to in situ histochemistry results and were negative for TCR gene rearrangement, consistent with primary NK lymphoma of the GI tract. The other patient was EBER negative with rearranged TCR, consistent with NK-like T-cell lymphoma. There was no clinical or histologic evidence of enteropathy in any of the patients. The major presenting symptoms included fever, weight loss, and intestinal perforation. All patients died between 1 week and 6 months after diagnosis despite undergoing surgery and intensive chemotherapy. CONCLUSIONS: These results, together with a literature review, suggest that primary NK cell lymphoma of the GI tract may be considered a distinct clinicopathologic entity. Both primary NK and NK-like T-cell lymphoma pursue an aggressive clinical course. EBER and TCR gene rearrangement are useful in distinguishing NK cell lymphoma from NK-like T-cell lymphoma, particularly when frozen tissue is not available for immunophenotyping. 相似文献
224.
Lal G Ash C Hay K Redston M Kwong E Hancock B Mak T Kargman S Evans JF Gallinger S 《Cancer research》2001,61(16):6131-6136
Epidemiological studies suggest that nonsteroidal anti-inflammatory agents decrease the risk of colorectal cancer. This is believed to be mediated, at least in part, by inhibition of cyclooxygenase (COX) activity. There are two COX isoenzymes, namely the constitutively expressed COX-1 and the inducible COX-2. COX-2 is overexpressed in adenomas and colorectal cancers, and COX-2-specific inhibitors have been shown to inhibit intestinal polyps in Apc(Delta716) mice more effectively than dual COX-1/COX-2 inhibitors such as sulindac. Various Apc knockout mice, including the multiple intestinal neoplasia (Min) mouse and the Apc(Delta716) mouse, are limited by their lack of large numbers of colonic adenomas and aberrant crypt foci, the putative precursors of large-bowel polyps and cancers. Our DNA mismatch-repair-deficient Min mouse model (Apc+/-Msh2-/-) has genetic features of both familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer, and most importantly, rapidly develops numerous small- and large-bowel adenomas, as well as colonic aberrant crypt foci. The purpose of this study was to determine the effects of COX inhibitors on intestinal adenomas and colonic aberrant crypt foci in this accelerated polyposis, mismatch-repair-deficient Min mouse model, in addition to a standard Min mouse model. Weanling Apc+/-Msh2-/- and Min mice were fed diets containing no drug, sulindac, or a specific COX-2 inhibitor (MF-tricyclic). Apc+/-Msh2-/- and Min mice were sacrificed after 4 weeks and 5 months on diet, respectively. Apc+/-Msh2-/- mice treated with MF-tricyclic had significantly fewer small-bowel polyps (mean +/- SD, 178 +/- 29) compared with mice on sulindac (278 +/- 80), or control diet (341 +/- 43; P < 0.001). There was no difference in numbers of large-bowel polyps or aberrant crypt foci in mice in the three groups. MF-tricyclic was also effective in reducing both small- and large-bowel polyps in Min mice. Western analysis demonstrated COX-2 expression in both large- and small-bowel polyps from mice of both genotypes. This study demonstrates that a specific COX-2 inhibitor is effective in preventing small-bowel polyps in mismatch-repair-deficient Min mice and both small- and large-bowel polyps in standard Min mice. Therefore, specific COX-2 inhibitors may be useful as chemopreventive and therapeutic agents in humans at risk for colorectal neoplasia. 相似文献
225.
Acute myeloid leukemia precipitated by dengue virus infection in a patient with hemoglobin H disease
We report a unique case of refractory acute myeloid leukemia (AML) precipitated by dengue virus induced marrow aplasia in a Chinese patient with hemoglobin (Hb) H disease. The quick temporal sequence of the three marrow abnormalities: hereditary hemoglobinopathy, reactive viral induced marrow change and malignant neoplastic process is highly unusual. Neither HbH disease nor viral induced marrow aplasia has known associations with AML. We propose that this unique case of AML may be caused by cytokine hyperstimulation in a stressed marrow. 相似文献
226.
Multicentric Castleman's disease (MCD) of plasma cell type is a reactive lymphoproliferative disease. While 67Ga scanning is useful in the detection of malignant lymphomas, its role in reactive lymphadenopathy is unknown. We report the absence of 67Ga uptake in three patients with MCD of plasma cell type and present a review of the English literature on this condition. 相似文献
227.
228.
Bioactive transforming growth factor-beta in the lungs of extremely low birthweight neonates predicts the need for home oxygen supplementation 总被引:4,自引:0,他引:4
Lecart C Cayabyab R Buckley S Morrison J Kwong KY Warburton D Ramanathan R Jones CA Minoo P 《Biology of the neonate》2000,77(4):217-223
Transforming growth factor-beta (TGF-beta) is a peptide implicated in tissue injury and repair but its role in the premature human lung remains unclear. In the present study, we used a TGF-beta responsive-promoter-luciferase construct in mink lung epithelial cells to quantify levels of biologically active TGF-beta (BA-TGF-beta) in the endotracheal aspirate (ETA) fluid from 16 extremely low birthweight neonates [6 M/10 F, mean GA 26 weeks (range 23-30), mean BW 774 g (range 555-1,075)]. ETA fluid was obtained on day 1 and then every 4 days up to 32 days. BA-TGF-beta levels were low (92 +/- 19 pg/ml) in the first 24 h of life and then increased 5- to 10-fold with peak BA-TGF-beta levels (400 +/- 50 pg/ml) on day 20-25. BA-TGF-beta levels were higher in male than female infants (p = 0.0056). Prenatal steroids decreased significantly the amount of BA-TGF-beta recovered. High initial levels of BA-TGF-beta persisted over time and were predictive of the need for oxygen therapy at home. We conclude that abundant BA- TGF-beta is present in the lungs of preterm infants and speculate that it may be involved in inflammatory and repair processes encountered in acute and chronic lung disease. 相似文献
229.
Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested. 相似文献
230.
BACKGROUND AND PURPOSE: Physical therapists often use positioning to assist in the reexpansion of collapsed lung segments. An increase in lung sound intensity on auscultation is considered indicative of lung expansion. This study was designed to examine whether clinical interpretation of auscultatory findings is warranted. SUBJECTS: The subjects (5 male, 6 female) were young physical therapist students without pulmonary dysfunction (mean age=20.4 years, mean height=166.3 cm, mean weight=57.5 kg). Subjects with lung disease were excluded because pulmonary pathology is difficult to standardize. METHODS: Lung sounds electronically recorded over the posterior chest wall of subjects in sitting and side-lying positions were compared. Measures included peak intensity, frequency at maximum power, and median frequency. RESULTS: In the sitting position, inspiratory sounds recorded over the left posterior chest wall were louder than those recorded on the right side. In the side-lying positions, the sound intensity recorded from the dependent chest wall was louder than that recorded from the nondependent chest wall. In side-lying positions, the upper hemithorax is "nondependent," and the side in contact with the bed is "dependent." Sound intensities recorded over both posterior chest walls in the sitting position were louder than those recorded over the same lung area in the nondependent side-lying position. There was no difference in the sound intensity recorded between the sitting and dependent side-lying postures. CONCLUSION AND DISCUSSION: When comparative auscultation of the chest wall is used by physical therapists to assess the adequacy of pulmonary ventilation, patient posture and regional differences in breath sound intensity can influence clinical interpretation. 相似文献