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91.
Eugenia Arias Horacio Martinetto Marcelo Schultz Sebastian Ameriso Santiago Rivera Oscar Lossetti Gustavo Sevlever 《Diagnostic molecular pathology》2006,15(3):174-179
A polymerase chain reaction (PCR) method for the detection of the glmM gene, selected as Helicobacter pylori target sequence, was improved. While performing pathogenicity island cagA gene detection to discriminate pathogenic strains in atherosclerotic carotid samples, several cagA-positive but glmM-negative samples were found. Polymorphisms present in the region amplified in the nested PCR reaction could explain this result; primers were therefore designed to perform a seminested reaction; this modification optimized sensitivity while maintaining specificity. A real-time PCR for Helicobacter DNA detection was also setup. The combination of all 4 PCR reactions detected 83% of H. pylori DNA-positive samples in atherosclerotic carotid tissue, 64% of which were cagA gene positive. 相似文献
92.
Paulo Roberto Ferreira Cerqueira Belmiro Cavalcanti do Egito Vasconcelos Ricardo Viana Bessa-Nogueira 《Journal of oral and maxillofacial surgery》2004,62(1):57-61
PURPOSE: Postoperative variables such as pain, swelling, and trismus after surgery of the impacted lower third molars are the main concerns of dental clinicians and surgeons. Many authors claim that the use of a drain could help control these variables. The purpose of this study was to evaluate the effect of the use of a tube drain in impacted lower third molar surgery. MATERIALS AND METHODS: Fifty-three patients of both genders with bilateral impacted lower third molars comprised our comparative study. The patients were divided into 2 groups: in the first the suture procedure was accomplished using a drain, and in the second the suture procedure was accomplished without a drain. The postoperative pain, swelling, and trismus were evaluated at 24 hours, 72 hours, 7 days, and 15 days. RESULTS: In the group in which the drain was used, the control of the swelling variable was statistically significant at 24 and 72 hours (P <.001) in comparison with the group in which the drain was not used. However, pain and trismus were not statistically significant at the evaluation period. CONCLUSION: The use of the drain helps to control swelling. However, it had no effect on pain or trismus. 相似文献
93.
Separate visual pathways for perception of actions and objects:
evidence from a case of apperceptive agnosia 下载免费PDF全文
C. T. Ferreira M. Ceccaldi B. Giusiano M. Poncet 《Journal of neurology, neurosurgery, and psychiatry》1998,65(3):382-385
Recognition of different kinds of visual stimuli was studied ina patient who acquired apperceptive visual agnosia after a bilateraloccipitotemporal lesion which partially spared the primary visualcortex. Impairment in recognising static objects perceived visuallysharply contrasts with the relatively well preserved ability torecognise objects from gestures illustrating their use, and torecognise actions shown in line drawings. It is suggested that theoccipitoparieto-frontal pathway is involved in the recognition ofactions, and in the recognition of objects when sensorimotor experienceis evoked.
相似文献
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94.
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
95.
In a catamnestic study an analysis of the clinical results as well as of the spermatograms are reported on 545 andrological patients with "atrophy" (that means reduced testis volume) or absence of one testis and a contralaterally normal developed testis. It can be demonstrated that there do not exist any differences concerning the size and consistency of the present testis and with regard to absence or lost of one testis (hemicastration). In case of testicular atrophy exists a more disadvantageous reproductive function. In case of tumor as a reason for hemicastration the teratoma shows better conditions for the quality of the spermatograms and for reproduction. Accordingly the histological findings of the testis after hemicastration/absence are not so large in the present remained testis. In cases of one-sided orchitis the spermatogram quality is better than in one-sided varicocele with atrophy at the same side. 相似文献
96.
Dynamic graciloplasty for urinary incontinence: the potential for sequential closed-loop stimulation
Zonnevijlle ED Perez-Abadia G Stremel RW Maldonado CJ Kon M Barker JH 《Medical engineering & physics》2003,25(9):755-763
Muscle tissue transplantation applied to regain or dynamically assist contractile functions is known as 'dynamic myoplasty'. Success rates of clinical applications are unpredictable, because of lack of endurance, ischemic lesions, abundant scar formation and inadequate performance of tasks due to lack of refined control. Electrical stimulation is used to control dynamic myoplasties and should be improved to reduce some of these drawbacks. Sequential segmental neuromuscular stimulation improves the endurance and closed-loop control offers refinement in rate of contraction of the muscle, while function-controlling stimulator algorithms present the possibility of performing more complex tasks. An acute feasibility study was performed in anaesthetised dogs combining these techniques. Electrically stimulated gracilis-based neo-sphincters were compared to native sphincters with regard to their ability to maintain continence. Measurements were made during fast bladder pressure changes, static high bladder pressure and slow filling of the bladder, mimicking among others posture changes, lifting heavy objects and diuresis. In general, neo-sphincter and native sphincter performance showed no significant difference during these measurements. However, during high bladder pressures reaching 40 cm H(2)O the neo-sphincters maintained positive pressure gradients, whereas most native sphincters relaxed. During slow filling of the bladder the neo-sphincters maintained a controlled positive pressure gradient for a prolonged time without any form of training. Furthermore, the accuracy of these maintained pressure gradients proved to be within the limits set up by the native sphincters. Refinements using more complicated self-learning function-controlling algorithms proved to be effective also and are briefly discussed. In conclusion, a combination of sequential stimulation, closed-loop control and function-controlling algorithms proved feasible in this dynamic graciloplasty-model. Neo-sphincters were created, which would probably provide an acceptable performance, when the stimulation system could be implanted and further tested. Sizing this technique down to implantable proportions seems to be justified and will enable exploration of the possible benefits. 相似文献
97.
Free-living, Amphizoic and Opportunistic Amebas 总被引:9,自引:0,他引:9
Augusto Julio Martinez Govinda S. Visvesvara 《Brain pathology (Zurich, Switzerland)》1997,7(1):583-598
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
98.
A Ferreira M C García Rodríguez F Ome?aca A Jiménez L M Villar P Gonzalez-Porqué G Fontán 《Clinical and experimental immunology》1991,84(1):167-169
In this work we have quantified soluble class I histocompatibility antigens (s-HLA) and beta 2-microglobulin (beta 2 m) in sera of HIV+ or HIV- mothers at delivery and in cord blood sera of their newborn children. The results obtained for beta 2 m show that cord blood sera of newborn children have higher concentrations than their mothers, implying that most of the beta 2 m in the newborn is self-produced as described previously. s-HLA serum concentrations in the newborn children are significantly lower than in their mothers or in age-matched controls. Moreover, HIV+ mothers have significantly higher serum concentrations than HIV- mothers or an age-matched control group. These results suggest that s-HLA does not cross the placental barrier. 相似文献
99.
Evaluation of stromal metalloproteinases and vascular endothelial growth factors in a spontaneous metastasis model 总被引:5,自引:0,他引:5
Donadio AC Durand S Remedi MM Frede S Ceschin DG Genti-Raimondi S Chiabrando GA 《Experimental and molecular pathology》2005,79(3):259-264
This study aims to investigate MMP2 and MT1-MMP protein as well as VEGF-C and VEGF-D mRNA expression in tumor cells and distant organs considered to be targets for metastasis in a tumor spontaneous metastasis model previously described. Cultured tumor cells, able to express pro-MMP2, MMP2, pro-MMP9, and MT1-MMP, develop tumor growth and metastasis, mainly in the liver and spleen, when they are injected in the mammary pad gland of Wistar rats. Immunohistochemical studies of tumor masses showed small groups of tumor cells staining for MT1-MMP but not for MMP2. In the liver, tumor metastatic foci and a stromal positive staining for both MMP2 and MT1-MMP were shown. The spleen and lymph nodes, with only scattered metastatic cells, did not show MMPs immunostaining. Using RT-PCR, a significantly higher VEGF-C and VEGF-D gene expression was shown in the liver of tumor-bearing rats respect to normal rats, whereas spleen and lymph nodes did not show significant differences in mRNA VEGF-C/D levels. Taken together, our results suggest that the stroma microenvironment of target organs for metastasis has the ability to produce MMPs and VEGFs that facilitate the anchorage of tumor cells and promote tumor cell growth and angiogenesis. 相似文献
100.
Performance characteristics of a rapid new immunochromatographic test for detection of antibodies to human immunodeficiency virus 总被引:1,自引:0,他引:1
Ribeiro-Rodrigues R Ferreira da Silva Pinto Neto L Cunha CB Cabral VP Dietze R 《Clinical and diagnostic laboratory immunology》2003,10(2):303-307
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers. 相似文献