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81.
82.
Bulletin of Environmental Contamination and Toxicology - Halogenated compounds are one of the largest groups of environmental-hazardous chemicals. The removal of the halogen atom from the substrate...  相似文献   
83.
Tuberculosis of the middle ear it a rare disease. Due to change in the typical clinical pattern and decrease in incidence, there is a delayed or missed diagnosis and can lead to increased morbidity. We pretent 5 cases of Tuberculous Otitis Media treated over a period of 2 years, highlighting the fact that it must be considered as a differential diagnosis of persistent suppurative otitis media.  相似文献   
84.
Conventional cancer therapies such as surgery, chemotherapy and/or radiotherapy, are not always successful in providing long-term survival for cancer patients. One of the major problems with conventional cancer therapies is their inability to eradicate residual/metastatic tumor cells that are resistant to therapy. Therefore, it is necessary to develop new methods for treating such cancer cells in order to improve the clinical outcome of these patients. Despite antitumor effector mechanisms working against cancer cells in the host's body, tumor-cell-induced immunosuppression and or antigenic modulation by the tumor cells often help tumor cells escape host defense mechanisms. Therefore, one approach for treating residual cancer would be to enhance the host's own immunological/antitumor defense mechanisms. Immune cells that have a significant role in mediating antitumor responses include: T lymphocytes; natural killer (NK) cells; macrophages; and B lymphocytes. The ability of these immune cells to effectively destroy malignant cells is carefully governed by chemical mediators in the form of proteins otherwise known as cytokines. Many cytokines (interleukins, interferons, and tumor necrosis factor) have been shown to enhance in vitro and in vivo effector cell antitumor cytotoxic activities. Utilization of cytokines in conjunction with effector cells can also mediate significant antitumor responses in both animal models and cancer patients. One of the major problems associated with systemic treatment with cytokines is the development of dose limiting toxicities. Currently, attempts to reduce this problem include developing techniques to allow for the preferential release of cytokines in proximity to the tumor cell. In this regard, effector cells or tumor cells that have been genetically engineered to secrete cytokine(s) may be useful in localizing an immune response, preferably at the tumor site. Clinical trial using cytokine gene transfected cells for treating cancer are currently under investigation. With the availability of recombinant lymphokines and with our ability to genetically modify effector cells and tumor cells this hopefully will allow us to improve current therapeutic modalities for treating cancer.  相似文献   
85.
OBJECTIVES: This study examined client and program characteristics that predict posttreatment cocaine abstinence among cocaine abusers with different treatment histories. METHODS: Cocaine abusers (n = 507) treated in 18 residential programs were interviewed at intake and 1-year follow-up as part of the nationwide Drug Abuse Treatment Outcome Study (DATOS). Program directors provided the program-level data in a mail survey. We applied the hierarchical linear modeling approach for the analysis. RESULTS: No prior treatment and longer retention in DATOS programs were positive predictors of posttreatment abstinence. The interactive effect of these 2 variables was also significantly positive. Program that offered legal services and included recovering staff increased their clients' likelihood of cocaine abstinence. Crack use at both the client and program level predicted negative impact. None of the program variables assessed differentially affected the outcomes of first-timers and repeaters. CONCLUSIONS: Although treatment repeaters were relatively difficult to treat, their likelihood of achieving abstinence was similar to that of first-timers if they were retained in treatment for a sufficient time. First-timers and repeaters responded similarly to the treatment program characteristics examined. The treatment and policy implications of these findings are discussed.  相似文献   
86.
87.
In a prospective, randomized trial, 205 febrile episodes in granulocytopenic cancer patients were treated with ceftazidime with or without tobramycin (C±T), both agents being administered only if the initial granulocyte count was below 200/l, or ceftazidime plus piperacillin (C+P). The overall response rate was 71% (39 of 60 for C±T and 45 of 58 for C+P). Logistic regression analyses documented no evidence of a significant difference between the two regimens in overall treatment effect after accounting for the linear effects of potentially important variables, such as infection type and granulocyte count. Although the response rates for the subgroup of patients with bacteremias was better with the C+P regimen (P=0.06), there was no difference in response for patients with bacteremia and profound (<100/gml) sustained granulocytopenia. The double -lactam combination demonstrated in vitro synergism in 73%; antagonism was not seen. Both regimens produced execllent serum bactericidal levels (C±T geometric mean peak 1:170; C+P peak 1:137) against gram-negative but not gram-positive pathogens (1:4; 1:7 respectively) that had caused bacteremia. Emergence of resistance and significant coagulopathy and/or bleeding did not occur during therapy. Antibiotic-related nephrotoxicity was noted in 7 of 95 trials in the C+P and in 6 of 89 trials in the C±T group (P=0.19). The incidence of secondary infections in patients with profound (<100/l) sustained granulocytopenia was lower in the C±T group (P=0.04). Alimentary canal anaerobic flora preservation with C±T, and suppression with C+P, was demonstrated. These results suggest that these regimens are of similar effectiveness and neigher is associated with major toxicity.  相似文献   
88.
OBJECTIVE: The diagnosis of early local recurrence of soft tissue sarcomas, especially in those treated with surgery and radiotherapy, is a difficult clinical problem. Financial constraints led us to use ultrasonography instead of CT or MR imaging. The aim of this study was to evaluate the role of ultrasonography (US) in detecting local recurrence. METHODS AND RESULTS: Fifty patients with previous treatment for soft tissue sarcomas were evaluated prospectively for recurrence by US and histopathology. Seven of the 50 patients were clinically suspected to have recurrent tumour. Ultrasonography showed recurrence in 26, no recurrence in 18, benign disease in four and was indeterminate in two cases. Ultrasonography was instrumental in guiding fine needle aspiration biopsies of small local recurrences and indeterminate lesions in 17 patients. In the sonographically tumour positive patients, histopathology confirmed recurrence in 24; one case had benign disease and one patient refused surgery. Thirteen of the 18 sonographically tumour negative patients were operated upon; all were negative for tumour on histopathology. Both the indeterminate cases showed recurrence on histopathology. The benign cases were confirmed by histopathology correlation. Ultrasound guided fine needle aspiration cytology (FNAC) was positive in 14 out of 17 patients (88%). The sensitivity and specificity of US was 92.30% and 94.4% respectively. CONCLUSION: Our study concludes that US is an extremely useful and cost effective method in the detection of early local recurrences of soft tissue sarcomas and should therefore be used for initial routine follow-up and guided biopsies.  相似文献   
89.
We report the results of a series of 59 unconstrained total arthroplasties of the elbow after a mean follow-up of 6.5 years (4 to 10). All the patients had rheumatoid arthritis. The indication for surgery was pain in all but one. Outcome was assessed by the Mayo Elbow Performance Index (MEPI). Of the 59 arthroplasties, two were lost to follow-up. Ten patients died, but as two of their arthroplasties were failures we included them in the results. The outcome in the remaining 49 was excellent in 26 (53%), good in 15 (31%), fair in one (2%) and poor or a failure in seven (14%). There was an improvement in the pain score (p < 0.001), movement (p < 0.001) and function (p < 0.001). Two patients developed instability, but neither required further surgery. There was a mean increase of 21 degrees in flexion and of 7 degrees in extension. The overall rate of complications was 33.9%. Lesions of the ulnar nerve, one of which did not recover, occurred in four patients, deep infection in two and stiffness in five. The rates of complications were similar to those in recent reports of other elbow arthroplasties. We carried out a radiological analysis of 39 arthroplasties which showed radiolucent lines around the humeral component in 22 and the ulnar component in 15. There were lower scores on the MEPI for those with radiolucent lines around the humeral component.  相似文献   
90.
Ultrastructural investigation of human sperm using atomic force microscopy   总被引:3,自引:0,他引:3  
Ultrastructural investigation of human sperm in its natural environment (without fixation, dehydration, embedding, sectioning, etc.) was carried out by using atomic force microscope (AFM) in its tapping mode. This technique permits the examination of fine structural details of undamaged sperm and its topography with precision. Moreover, it allows 3D reconstruction of images and enhances the contrast to resolve details such as mitochondria that surround the axoneme at the sperm middle piece. An organized structure has been found in the flageller axoneme region. Ultrastructure also reveals folding and details of the depression of the membrane that cannot be examined with conventional techniques.  相似文献   
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