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21.
Recent years have seen increasing interest in devising methods of studying psychodynamic phenomena. These efforts have had confront difficulties, first, in specifying the data, the observation language, and rules of inference for psychodynamic propositions, and second, in determining the reliability and validity of the measures used. Given how "fuzzy" traditional psychodynamic concepts are, it is no wonder that psychodynamic clinicians from Freud onward have achieved more success in generating new hypotheses than in testing their validity. As Reichenbach (1938) has observed, science requires that discovery be followed by systematic validation of all new propositions, regardless of their degree of popular acceptance. At the core of efforts to study psychodynamics have been methods to study ego functioning (Bellak and Goldsmith 1984), defense mechanisms (Perry and Copper 1988), and psychodynamic conflicts. This paper reports on the reliability of the Idiographic Conflict Formulation (ICF), a guided method for formulating an individual's psychodynamic conflicts.  相似文献   
22.
Free-living, Amphizoic and Opportunistic Amebas   总被引:9,自引:0,他引:9  
Amebas belonging to the genera Naegleria, Acanthamoeba and Balamuthia are free-living, amphizoic and opportunistic protozoa that are ubiquitous in nature. These amebas are found in soil, water and air samples from all over the world. Human infection due to these amebas involving brain, skin, lung and eyes has increased significantly during the last 10 years. The epidemiology, immunology, protozoology, pathology, and clinical features of the infections produced by these protozoa differ strikingly. Infection by the pathogenic Naegleria fowleri is acquired by exposure to polluted water in ponds, swimming pools and man-made lakes. Raised temperatures during the hot summer months or warm water from power plants facilitate the growth of N. fowleri. N. fowleri is a thermophilic ameba that grows well in tropical and subtropical climates. The CNS infection, called Primary Amebic Meningoencephalitis (PAM), produced by N. fowleri is characterized by an acute fulminant meningoencephalitis leading to death 3–7 days after exposure. Victims are healthy, young individuals with a history of recent water-related sport activities. The portal of entry is the olfactory neuroepithelium. The pathologic changes are an acute hemorrhagic necrotizing meningoencephalitis with modest purulent exudate, mainly at the base of the brain, brainstem and cerebellum. Trophozoites can be seen within the CNS lesions located mainly around blood vessels. Thus far 179 cases have been reported; 81 in the USA alone. Balamuthia mandrillaris and several species of Acanthamoeba are pathogenic “opportunistic” free-living amebas which cause Granulomatous Amebic Encephalitis (GAE) in humans and animals. GAE is an infection, usually seen in debilitated, malnourished individuals, in patients undergoing immunosuppressive therapy for organ transplants and in Acquired Immunodeficiency Syndrome (AIDS). The granulomatous component is negligible, particularly in immunocompromised individuals. Pathologically these amebas produce a patchy, chronic or subacute granulomatous encephalitis with the presence of trophozoites and cysts. The portal of entry is probably through the respiratory tract or an ulceration of the skin reaching the CNS by hematogenous spread. As of October 1, 1996, 166 cases 1103 due to Acanthamoeba and 63 due to Balamothial of GAE have been reported from around the world. Of these 103 cases due to Acanthamoeba (72 have been reported in the USA alone, > 50 in AIDS). It is well known that several species of Acanthamoeba can also produce, chronic sight threatening ulceration of the cornea called Acanthamoeba keratitis (AK), mostly in contact lens wearers or in individuals with minor corneal abrasions. Hundreds of cases of AK have been documented world wide.  相似文献   
23.
Granular cell tumors (GCT) are uncommon benign neoplasms that have a predilection for the head and neck region. These tumors can frequently be associated with pseudoepitheliomatous hyperplasia (PEH), which in turn may be mistaken for squamous cell carcinoma. Although epidermal growth factors are overexpressed in squamous cell carcinomas of the head and neck, their presence in PEH, especially its relation to GCT, is unknown. We hypothesize that the expression of epidermal growth factor receptor (EGFR), epidermal growth factor (EGF), and transforming growth factor alpha (TGFalpha) in GCT have a role in the development of PEH overlying some GCT. Sections from 13 cases of GCT (five with overlying PEH) were examined histologically and evaluated immunohistochemically using monoclonal antibodies for EGFR, EGF, and TGFalpha. These were compared with nine cases of PEH independent of GCT. Two of five GCT with overlying PEH and two of six GCT without overlying PEH stained positively for TGFalpha. None of the GCT stained with EGFR or EGF. All cases of PEH, whether or not associated with GCT, were reactive for EGFR and EGF. Four of the five cases of PEH overlying GCT stained with TGFalpha. The staining pattern and intensity of all three antibodies were comparable to that of the adjacent normal squamous mucosa. Among the three antibodies, only TGFalpha in GCT appears to be related to the development of PEH. Epidermal growth factor receptor and EGF do not seem to be directly involved. The reason of PEH formation associated with GCT in the absence of growth factors is unknown.  相似文献   
24.
Computer analysis showed that the gene encoding the latex test-reactive protein of Clostridium difficile exhibited high levels of homology with glutamate dehydrogenases from various sources. Further analysis demonstrated that the recombinant protein possessed glutamate dehydrogenase activity. Our results show that the protein that reacts in commercial latex tests for C. difficile is a glutamate dehydrogenase.  相似文献   
25.
A frame-shift 9254del5 mutation was independently identified in 12 families, eleven of them with Spanish ancestors, in a BRCA2 screening performed in 841 breast and/or ovarian cancer families and in 339 women with breast cancer diagnosed before the age of 40 at different centers in France and Spain. We sought to analyze in detail the haplotype and founder effects of the 9254del5 and to estimate the time of origin of the mutation. Eight polymorphic microsatellite markers and two BRCA2 polymorphisms were used for the haplotype analyses. The markers were located flanking the BRCA2 gene spanning a region of 6.1 cM. Our results suggest that these families shared a common ancestry with BRCA2 9254del5, which is a founder mutation originating in the Northeast Spanish, with an estimated age of 92 (95% CI 56-141) generations.  相似文献   
26.
The effects of tolerance to Escherichia coli endotoxin on the phagocytic and bactericidal activity of the hepatic reticuloendothelial system against viable E. coli were examined using ex vivo perfused rat livers. Livers were isolated from control and endotoxin-tolerant rats and perfused with a medium containing 5% homologous serum from either control or tolerant rats. After the addition of the E. coli (2 × 107 cells per ml) to the perfusate, the hepatic clearance of the bacteria was followed for 30 min. The highest activation of the hepatic reticuloendothelial system was observed when serum from tolerant animals was added to the perfusate. Under these conditions phagocytosis was 47% (12% in controls), and 37 to 38% of the bacteria were killed (5% in controls). This activation was less when livers obtained from tolerant rats were perfused with serum from controls or with saline only. The data suggests that, during endotoxin tolerance, humoral factors play an important role in the activation of the hepatic reticulendothelial system, although a direct stimulation of Kupffer cells also occurs. The enhancement of phagocytosis by tolerant serum did not require the presence of homologous antibodies and involved the activation of the alternative complement pathway, since it was lost after removal of factor B activity. On the other hand, stimulation of intracellular killing required both complement and specific antibodies. The data suggest a role of endotoxin in the activation of humoral and cellular mechanisms involved in the host resistance to gram-negative bacterial infection.  相似文献   
27.
28.
Since its inception in November 1997, the Cervical Cancer Screening Program of Paraná (CCSPP), Brazil, has resulted in the cytological screening of 2,244,158 women, the coverage of the female population increasing from 43% to 86%. One thousand six hundred one cases screened by cytology, submitted to colposcopy, and subjected to treatment were selected. Cytopathological results were compared with those obtained on the basis of histological analyses of the loop electrical excision procedure specimens, and were subjected to statistical analyses. The data obtained were then compared with cytohistological correlation results from the first year of the program. Considering the exact correlation between cytological and histological diagnoses, the correlation index increased from 53.34% in the first year to 67.3% at the end of 5 yr of the program. Variations that occurred in each diagnostic category are discussed. This study demonstrates a significant improvement in the concordance between cytological and histological results for the 5-yr period compared with the first year of the CCSPP.  相似文献   
29.
We report 3 cases of a new renal cell tumor entity with a review of the literature. These 3 cases were retrieved from the files of this institution from 1991 to 2002. The clinical data and all histologic slides were reviewed and an immunohistochemical study was performed. Patients were all females. Tumors were almost similar with well-defined margins. Tumor architecture was tubular and focally fusiform with an abundant myxoid stroma. Tumor cells were low cuboidal, slightly eosinophilic with low nuclear grade. Immunohistochemistry was in favor of a distal nephron differentiation. All patients were healthy after surgery. We describe 3 cases of a new clinicopathological entity entitled low-grade tubular myxoid renal tumor with a benign clinical course.  相似文献   
30.
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms.  相似文献   
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