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1.
Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
  相似文献   
2.
Blastomycosis     
Blastomycosis is an uncommon, sometimes self-healing, sometimes fatal, infectious disease caused by the fungus Blastomyces dermatitidis. Although amphotericin B is still considered the drug of choice, ketoconazole and several other imidazole drugs--miconazole, itraconazole, econazole--have shown promise in the treatment of blastomycosis.  相似文献   
3.
4.
We studied 33 patients presenting with a peripheral neuropathy associated with non-malignant anti-myelin-associated glycoprotein (MAG) IgM monoclonal gammopathy (MG) in an attempt to delineate their clinical, immunological, electrophysiological and pathological characteristics; we also reviewed our experience concerning long-term follow-up and therapy. Peripheral neuropathy associated with non-malignant anti-MAG IgM MG was observed mostly in males (sex ratio 7.2), and mean age at onset was 67 years (range 46–81). A predominantly sensory pattern was noted in more than 80% of cases, although some patients were affected by a predominantly motor peripheral neuropathy. Although disease progression was slow in most cases, 45% of patients suffered severe disability, and in 2 cases, the patient's death appeared to stem directly from the neuropathy. The electrophysiological findings were indicative of a demyelinating process in 90% of cases, and electron microscopic examination of nerve biopsy specimens demonstrated widening of the myelin lamellae in more than 95% of cases. Most of our patients showed a disappointing response to steroids and chemotherapy or plasma exchanges. Intravenous immune globulin, evaluated in 17 patients, had a transient, mostly subjective effect in 35% and led to a clear-cut improvement in 24% of cases. We did not observe any correlation between the severity of the clinical picture and the anti-sulphoglucuronyl paragloboside antibody titre; in individual cases, clinical improvement occurred without lowering of IgM levels. Although the severity and the rate of progression may greatly vary from patient to patient, the combination of clinical, electrophysiological and pathological features delineates a characteristic pattern in peripheral neuropathy associated with non-malignant anti-MAG IgM MG.  相似文献   
5.
Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
  相似文献   
6.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
7.
Short-term stimulation of nonantigen-primed peripheral blood mononuclear leukocytes with interleukin-2 generates a population of oncolytic effectors designated "lymphokine-activated killer" (LAK) cells. These LAK cells express potent lytic activity against a wide spectrum of fresh or cultured autochthonous (patient's own) and allogeneic (unrelated) tumors, yet specifically spare normal tissues. In this study, cells derived from primitive neuroectodermal tumors of the posterior fossa (PNET-PF) were examined for their sensitivity to LAK cytolysis utilizing an in vitro 4-hour chromium-51-release assay. Five early-passage cell lines, derived from primary PNET-PF, demonstrated significant sensitivity to LAK cell cytolysis. Lysis was equally effective in culture medium and cerebrospinal fluid. Three freshly excised PNET-PF exhibited similar susceptibility to lysis by autochthonous LAK cells. Greatly increased expansion of LAK cell cultures could be achieved by short-term stimulation with monoclonal anti-CD3 antibodies in addition to interleukin-2 activation. These findings constitute the preliminary in vitro foundations for potential intrathecal adoptive immunotherapy of PNET-PF with LAK cells.  相似文献   
8.
Vaccinia virus phosphorylates myelin basic protein in the myelin membrane in vitro. In the presence of vaccinia virus cores maximally 1.5 mol and in the presence of intact virus 0.7 mol phosphate residues were incorporated into 1 mol of myelin basic protein in the myelin membrane. The peptides of myelin basic protein which were phosphorylated by the vaccinia virus kinase were clearly all different from the peptides which were phosphorylated by the endogenous myelin protein kinase.The viral modification of the encephalitogenic protein and its significance to immunological events is discussed.  相似文献   
9.
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.   相似文献   
10.
The response of human T lymphocytes against the nicotinic acetylcholine receptor (AChR) was studied in five patients with myasthenia gravis (MG) and in six healthy donors using either native Torpedo AChR or recombinant protein derived from the mammalian AChR α subunit (X4, residues 6–216 of mouse AChR α subunit). The present study demonstrates that (a) AChR-specific T helper cell lines can be generated from MG patients [either from peripheral blood lymphocytes (PBL) or from thymocytes] as well as from PBL of normal controls, (b) lymphocytes from MG patients, but not from controls, recognize the mammalian AChR but not the Torpedo receptor, (c) in humans, the HLA-DR2-associated T cell epitope is probably located in the region of residues 162–216 of the AChR α subunit and (d) there is a considerable heterogeneity of autoreactive T cell responses: (i) Tcell lines from different HLA-type donors have distinct epitope profiles; (ii) the epitope specificity of the PBL-derived T cell line is different from that of the thymocyte-derived line; (iii) the epitope specificities of patient-derived T cell lines are different from those generated from normal controls who share the same HLA phenotype.  相似文献   
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