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31.
O. Díaz Rizo S. Olivares Reumont J. Viguri Fuente O. Díaz Arado N. López Pino K. D’Alessandro Rodríguez D. de la Rosa Medero A. Gelen Rudnikas G. Arencibia Carballo 《Bulletin of environmental contamination and toxicology》2010,84(1):136-140
Levels of iron, copper, zinc and lead were determined in sediments and soft tissue of the oyster Crassostrea rhizophorae collected from Guacanayabo Gulf, Cuba. Metal-to-Iron ratio in sediments shows an average enrichment for Cu (5,1), Pb (11,7)
and Zn (1,3) in the last 20 years. Metal concentrations found in soft tissue of C. rhizophorae are site dependent. The average biota-sediment accumulation factors (BSAFs) obtained for Fe, Cu and Pb are less than unity
in all cases, indicating that only a little fraction of Cu and Pb in the sediments is bioavailable, independently of their
enrichments. Zinc has an average BSAF value of 2.4 and may represent a serious impact in the area. The concentrations of zinc
and copper in some of the oysters are above typical public health recommended limits. 相似文献
32.
Background: Peritonitis continues to be an important cause of morbidity and mortality and often an etiologic diagnosis is unclear. To
evaluate the efficacy and safety of laparoscopy the authors analyzed their 5-year experience with this modality of treatment.
Methods: A review was made of 107 consecutive nonselected laparoscopic procedures performed between October 1990 and November 1995.
The diagnosis was established by clinical, laboratory, and imaging findings and confirmed by laparoscopy and/or laparotomy.
Results: An etiologic diagnosis was unclear in 35% of the cases and was established in all by laparoscopy; 94 patients (87.9%) were
successfully treated by laparoscopy while 13 (12.1%) required conversion. Mortality was 4.6%; 14% had postoperative complications
and 7.4% had reoperations.
Conclusions: Laparoscopic surgery is safe and very efficient in the diagnosis and treatment of patients with peritonitis. In most instances
a definitive treatment can be carried out without conversion and has the additional and well-known advantages of minimally
invasive surgery.
Received: 15 March 1996/Accepted: 29 August 1996 相似文献
33.
Association of HLA-DQA1*03011-DQB1*0301 haplotype with the development of respiratory scleroma. 总被引:1,自引:0,他引:1
Luis Alberto Sánchez-Marín Daniel Bross-Soriano José Arrieta Simón Kawa-Karasik Víctor Martínez-Vilchis Rocío Jiménez-Lucio Angélica Olivo-Díaz 《Otolaryngology--head and neck surgery》2007,136(3):481-483
OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS. 相似文献
34.
Open microsurgical autograft of adrenal medulla to the right caudate nucleus in two patients with intractable Parkinson's disease 总被引:12,自引:0,他引:12
I Madrazo R Drucker-Colín V Díaz J Martínez-Mata C Torres J J Becerril 《The New England journal of medicine》1987,316(14):831-834
Recent experimental studies and one clinical case have suggested that grafting tissue from the adrenal medulla into the brain may ameliorate the signs of Parkinson's disease. We describe the treatment of two young patients (35 and 39 years old) with intractable and incapacitating Parkinson's disease, in whom fragments of the adrenal medulla were autotransplanted to the right caudate nucleus. Clinical improvement was noted in both patients at 15 and 6 days (respectively) after implantation and has continued in both. Rigidity and akinesia had virtually disappeared in the first patient at 10 months after surgery, and his tremor was greatly reduced. A similar degree of improvement was present in the second patient at three months. We conclude that autografting of the adrenal medulla to the right caudate nucleus was associated with a marked improvement in the signs of Parkinson's disease in two patients, but our results are preliminary and further work is necessary to see whether this procedure will be applicable over the long term in other types of patients with Parkinson's disease. 相似文献
35.
36.
The purpose of this paper is to carry out an analysis of the term leukoplakia since its introduction in 1877 and to expose the most accepted concepts and present classification within specialists. For this purpose attention will be paid to definitions established in the international seminary developed in Malm? City, Sweden, in June 1983. A group of observations on present status of research and diagnostic methods and its limitations to pre-establish when a lesion of this type is going to evolve toward malignancy, is included. An important part of this paper is devoted to the linguistic analysis of leukoplakia and leukoplasia expressions. An extensive argumentation demonstrating the systematic impropriety in the Spanish Language of translating the English term "leukoplakia as leukoplasia, is presented. There is in Spanish the accurate translation, given by the expression leukoplakia, which is not only the adequate one for the exactness of its translation but also the one more conceptually adjusted to contemporary definition universally accepted, that is to say, a white plaque. Finally, a comment on importance of incorporates to our language the exact translation of scientific words, not only to fit it to present science, but also to a better fulfillment of its function in allowing the communication within Latin American researches themselves and with the world scientific community, is exposed. 相似文献
37.
Alvarez JC Díaz C Suárez C Fernández JA González del Rey C Navarro A Tolivia J 《Mechanisms of ageing and development》2000,114(3):149-172
The data concerning the effects of age on the brainstem are scarce and few works are devoted to the human vestibular nuclear complex. The study of the effects of aging in the vestibular nuclei could have clinical interest due to the high prevalence of balance control and gait problems in the elderly. We have used in this work eight human brainstems of different ages sectioned and stained by the formaldehyde-thionin technique. The neuron's profiles were drawn with a camera lucida and Abercrombie's method was used to estimate the total number of neurons. The test of Kolmogorov-Smirnov with the correction of Lilliefors was used to evaluate the fit of our data to a normal distribution and a regression analysis was done to determine if the variation of our data with age was statistically significant. Aging does not affect the volume or length of the vestibular nuclear complex. Our results clearly show that neuronal loss occurs with aging in the descending (DVN), medial (MVN), and lateral (LVN) vestibular nuclei, but not in the superior (SVN). There are changes in the proportions of neurons of different sizes but they are not statistically significant. The neuronal loss could be related with the problems that elderly people have to compensate unilateral vestibular lesions and the alterations of the vestibulospinal reflexes. The preservation of SVN neurons can explain why vestibulo-ocular reflexes are compensated after unilateral vestibular injuries. 相似文献
38.
Cristina Benito Eloína González-Mancebo M Dolores Alonso Díaz de Durana Rosa M Tolón Montserrat Fernández-Rivas 《Annals of allergy, asthma & immunology》2007,98(6):580-584
BACKGROUND: Coconut (Cocos nucifera) is a monocotyledonous plant of the Arecaceae family. Allergy to coconut is infrequent, with only 5 cases reported so far in the medical literature. OBJECTIVE: To identify coconut allergens in 2 patients allergic to this food. METHODS: We describe 2 patients allergic to coconut: an adult pollen-allergic patient monosensitized to coconut who presented with severe oropharyngeal symptoms and a child with a previous allergy to walnut, not allergic to pollen, who developed anaphylaxis on coconut ingestion. Both patients had positive skin prick test results and serum specific IgE (CAP) to coconut. IgE sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting was performed to identify the allergens involved, and a strong IgE binding band detected in both patients was further analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). Stability to pepsin digestion of the coconut extract and its cross-reactivity with tree nuts were studied. RESULTS: An immunoblot showed an almost identical profile of IgE binding proteins in the coconut extract in both patients who reacted strongly to a band of approximately 29 kDa. The peptide analysis by MALDI-TOF MS of this band obtained the sequence GHGKREDPEKR. The protein with the highest correlation with this peptide was found to be a 7S globulin from Elaeis guineensis, another oil palm species also belonging to the Arecaceae family. The 29-kDa band was digested by pepsin in less than 1 minute. Cross-reactivity among coconut, walnut, and hazelnut was demonstrated by CAP inhibition in patient 2. CONCLUSION: We have identified a 7S storage protein as a novel coconut allergen. 相似文献
39.
Evaluation of serological tests for diagnosis of Brucella melitensis infection of goats. 总被引:3,自引:2,他引:3 下载免费PDF全文
E Díaz-Aparicio C Marín B Alonso-Urmeneta V Aragn S Prez-Ortiz M Pardo J M Blasco R Díaz I Moriyn 《Journal of clinical microbiology》1994,32(5):1159-1165
Five serological assays were evaluated for the diagnosis of brucellosis in goats: the rose bengal test (RBT), complement fixation test (CFT), radial immunodiffusion (RID) with Brucella and Yersinia enterocolitica O:9 polysaccharides, counterimmunoelectrophoresis (CIEP) with cytosol, and enzyme-linked immunosorbent assay (ELISA) with polyclonal and protein G conjugates and smooth lipopolysaccharide (S-LPS), native hapten polysaccharide (NH), or cytosol antigens. For optimal sensitivity, RBT had to be used with sera-antigen at a 3:1 dilution. In the RID test, Brucella melitensis biotype 1 NH could not be replaced by Brucella abortus biotype 1 or Y. enterocolitica 0:9 polysaccharides. In the ELISA, S-LPS and NH gave similar results and the protein G conjugate increased the specificity. With the sera from 55 B. melitensis culture-positive goats, the sensitivity was 100% for RBT, CFT (titer > or = 4), and ELISA with S-LPS or NH; 94% for RID; and 93% for CIEP. All tests were negative (100% specific) when testing the sera from 127 brucella-free goats. Larger discrepancies among the results of the serological tests were obtained with sera from goats of areas where brucellosis is endemic. When the sera of 20 young goats vaccinated subcutaneously (10(9) CFU of B. melitensis Rev 1) and bled 6 months later were examined, the specificities were as follows: NH ELISA, 60%; CFT and S-LPS ELISA, 75%; RBT, 80%; CIEP, 90%; and RID, 94%. With the sera from 10 young goats vaccinated conjunctivally (10(9) CFU of B. melitensis Rev 1) all tests were 100% specific 4 months after vaccination. The proportion of goats giving a positive reaction after vaccination decreased faster in RID than in other tests. 相似文献
40.
HIV-1 vertical transmission is thought to mainly take place by virus crossing the placental barrier. However, the mechanism by which HIV-1-infects placental cells remains to be elucidated. We have found that purified cytotrophoblasts as well as trophoblastic cell lines are susceptible to infection by different HIV-1 isolates as detected by DNA-PCR and release of infectious virus, although with very low efficiency. Purified trophoblast or trophoblastic cell lines express low levels of chemokine receptors CCR-5 and CXCR-4 but not CD4 on the cell surface. To test if those molecules were used as receptors for HIV-1 infection, placental cells were pretreated with antibodies to CD4, CC-chemokines, C-X-C chemokines. None of those treatments inhibited HIV-1 infection. In contrast, we have found that HIV-1 infection of placental cells was increased in cocultures of infected T-cell blasts and placental cells. More interestingly, antibodies to beta(2) integrins and to LFA-1 were able to significantly block infection of placental cells. Cell surface expression of ICAM-1, an adhesion molecule involved in attachment of leukocytes to placenta, was upregulated in HIV-1-infected placental cells. Placental cells were able to transfer HIV-1 infection to T-cell blasts. This transmission required cell to cell contact and was also inhibited by anti-LFA-1 antibodies. In summary our results suggest that placental trophoblast could be infected by HIV-1 by a mechanism involving T cell to placental contact. Moreover, placental infection enhanced ICAM-1 expression and leukocyte adherence, an event which was required to transfer HIV-1 infection to T cells. This provides an explanation of the virus passing through the placental barrier during in utero HIV-1 vertical transmission. 相似文献