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41.
Phialemonium curvatum arthritis of the knee developed in a diabetic man following intra-articular injection of a corticosteroid. Cure was achieved with a 6-week course of intravenous amphotericin B deoxycholate. P.curvatum is commonly found in the environment and is often considered a contaminant; yet, its pathogenic potential should be seriously considered in selected patients.  相似文献   
42.
Primitive Neuroectodermal Tumors of the Central Nervous System   总被引:2,自引:0,他引:2  
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.  相似文献   
43.
Fifty cytologically malignant, five suspicious, and 27 cytologically benign serous effusions were assessed morphometrically for differences in mean and outlying nuclear and cytoplasmic variables. Significant differences were found between benign and malignant specimens for all nuclear morphometric variables measured, the most significant being largest nuclear area and diameter. No significant differences were found for cytoplasmic size variables. Although measurement of outlying values in serous effusions enhanced the difference between benign and malignant cell populations, it was of insufficient sensitivity or specificity to be of clinical diagnostic use. Increasing the sample size improved test performance but would be tedious to perform manually.  相似文献   
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BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors.  相似文献   
46.
We report a case of a life-threatening, recurrent, and azole-resistant pulmonary coccidioidomycosis in a patient receiving long-term fluconazole therapy for a history of coccidioidal meningitis. Since this diagnosis, the patient has received weekly amphotericin B for more than four years and remains in remission with a stable serum Coccidioides complement fixation antibody titer.  相似文献   
47.
An improved method for production of cirrhosis of the liver in rats is described. Rats are given CCl4 and phenobarbitone simultaneously. The method doubles the yield of cirrhotic animals and halves the time taken for their production, in comparison with CCl4 alone.CCl4 inhalation results in fewer intercurrent deaths than oral dosing of CCl4. The cirrhosis as observed histologically is accompanied by gross nodularity of the liver, splenomegaly, portal hypertension and testicular atrophy. About 50 per cent of animals have measurable ascites. Animals killed during application of the new method show that cirrhosis develops only after 4 weeks of CCl4 dosage.  相似文献   
48.
Y chromosome deletions encompassing the AZFc region have been reported in 13% of azoospermic men and 7% of severely oligozoospermic men. We examined the impact of these Y deletions on the severity of testicular defects in 51 azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after testicular sperm extraction (TESE) and 30 men with severe oligozoospermia undergoing ICSI after ejaculation of spermatozoa. In addition, five azoospermic patients shown previously to have Y chromosome deletions underwent histological evaluation of their previously obtained testis biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y chromosome AZFc region. Of these 10, five had spermatozoa retrievable from the testis, and in two cases the wives became pregnant. Of the 41 azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa retrievable from the testis, and in 12 cases (29%) the wives became pregnant. Four of 30 (13%) severely oligozoospermic patients were found to be deleted for AZFc and in three (75%) of these pregnancy was achieved. The other 26 severely oligozoospermic couples who had no AZFc deletions underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The embryo implantation rate was not significantly different for azoospermic (22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the total of 19 infertile men who had Y chromosome deletions, 14 had deletions within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14 had some spermatozoa (however few in number) in the ejaculate or testis. Five of the Y-deleted men had deletions that extended more proximally on the Y chromosome, and in none of these could any spermatozoa be observed in either ejaculate or testis. These results support the concept that, in azoospermic or oligozoospermic men with Y chromosome deletions limited to intervals 6D-6F (AZFc), there are generally very small numbers of testicular or ejaculated spermatozoa. Larger Y deletions, including and extending beyond the AZFc region and encompassing more Y genes, tend to be associated with a total absence of testicular spermatozoa. In those cases where spermatozoa were retrieved, the presence of Y deletions had no obvious impact on fertilization or pregnancy rate.   相似文献   
49.
50.
Differences between hyperkinetic children and normal children and the effects of methylphenidate on hyperkinetic children were investigated under conditions of differential attentional demands. Auditory average evoked potentials were recorded from vertex using a single/double click guessing paradigm under conditions of certainty and uncertainty. Under conditions of certainty (low attention), in which the subject was told the identity of each stimulus in advance, few significant group differences were found. Under conditions of uncertainty (high attention), in which the subject was asked to guess which stimulus would be presented, large group differences were found. In response to the second click the P200 component was found to be smaller and the N250 component was larger in hyperkinetic children than in normal children. Treatment with methylphenidate “normalized” the evoked potentials of the hyperkinetic children making them more like those of normal children. The findings are believed: 1) to reflect the deficit in attention observed behaviorally in hyperkinetic children, 2) to support a model of hypoarousal in hyperkinetic children, and 3) to reflect the behavioral “normalization” observed in hyperkinetic children treated with melhylphenidate.  相似文献   
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