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排序方式: 共有7952条查询结果,搜索用时 15 毫秒
31.
Giordano-Lanza G Guerra G Tafuri D 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》2002,107(4):215-223
Physical activity increases the work load of the heart. The adjustments of the heart depend on the quality and quantity of the work performed. These adjustments concern the function and the morphology of the cardiovascular system. It is important to underline that these adjustments are not permanent and can disappear when physical activity is stopped. In young subjects the risks are very few while the benefits may be shown on a better and more armonic body structure. In the elderly the benefits can be achieved with a lesser cost for submaximal activities, but the risks are of course more frequent due the possible onset of cardiovascular disease. It is important to correctly recognize the limits whitin which the physical activity can be allowed because beneficial. Echocardiography has given an important contribution to evaluate the morpho-functional adaptions of the athlete's heart. Similarly, it has proven useful in the detection of pathological cardiovascular modifications, asymptomatic or pausymptomatic, that do not allow certification to practise sport at agonistic levels. 相似文献
32.
Domenico de Aloysio Paola Altieri Paola Penacchioni Matteo Salgarello Vito Ventura 《Maturitas》1998,29(3):107-264
Objectives: To evaluate and to compare the bleeding patterns obtained with two regimens of hormone replacement therapy given to early postmenopausal women with asymptomatic uterine leiomyomas. Methods: In this randomised prospective 1-year study 50 early postmenopausal women with one to four asymptomatic uterine leiomyomas were enrolled into two study-groups to take two regimens of hormone replacement therapy for 12 28-day cycles: (A) Tibolone, 2.5 mg/day; (B) conjugated equine estrogens (CEE), 0.625 mg/day plus medroxyprogesterone acetate (MPA), 5 mg/day. The bleeding patterns and the changes in uterine volume of the 47 outpatients who completed the study were evaluated and compared. Results: Amenorrhea incidence was higher in group A (75.0% of the cycles) than in group B (65.6% of the cycles), while irregular bleeding and irregular spotting incidences were higher in group B (29.7 and 4.7% of the cycles, respectively) compared to group A (22.6 and 2.4% of the cycles, respectively). The mean bleeding and spotting lengths were not statistically different between patients in group A and those in group B. Finally, at the end of the study period transvaginal ultrasonography showed no significant change in leiomyoma size. Conclusions: The results demonstrate that, in early postmenopausal patients with asymptomatic uterine leiomyomas, Tibolone treatment seems to be preferable compared to CEE–MPA continuous combined treatment in relation to the lesser occurrence of irregular bleeding. Furthermore, neither Tibolone nor CEE–MPA therapy, at the doses used here, promote fibroid growth. 相似文献
33.
Reduction of capsular polysaccharide production in Klebsiella pneumoniae by sodium salicylate. 总被引:3,自引:3,他引:3
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Heavily encapsulated Klebsiella pneumoniae (serotypes 1 and 2) was cultured in the presence of sodium salicylate. The addition of salicylate (2 to 30 micrograms/ml) progressively decreased the amount of capsular polysaccharide produced by all strains without significantly inhibiting cell growth. Further addition of salicylate (50 to 200 micrograms/ml) was progressively inhibitory to cell growth and decreased the production of polysaccharide only slightly. The optimal concentration of salicylate that could reduce the polysaccharide production of heavily encapsulated, virulent strains by 50% or more was 30 micrograms/ml. Mutants of these bacteria that produced less capsule were affected by salicylate to a lesser degree. All concentrations of salicylate tested were physiologically achievable in humans and within the therapeutic range of aspirin. The addition of calcium and magnesium partially reversed the effects of salicylate on polysaccharide production. Chelating agents, particularly EGTA [ethylene-bis(oxyethylenenitrile)tetraacetic acid], reduce capsule production as salicylate did. Thus, the chelation of calcium and magnesium by salicylate could account, at least in part, for the reduction of capsule. Optical density measurements allowed for rapid monitoring of capsule production in various culture media because a large part of culture turbidity was apparently due to the capsule. Decreased production of the primary K. pneumoniae virulence factor with salicylate may have therapeutic potential. 相似文献
34.
Genotype-phenotype relationship in human ATP6i-dependent autosomal recessive osteopetrosis 总被引:5,自引:0,他引:5
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Taranta A Migliaccio S Recchia I Caniglia M Luciani M De Rossi G Dionisi-Vici C Pinto RM Francalanci P Boldrini R Lanino E Dini G Morreale G Ralston SH Villa A Vezzoni P Del Principe D Cassiani F Palumbo G Teti A 《The American journal of pathology》2003,162(1):57-68
Autosomal-recessive osteopetrosis is a severe genetic disease caused by osteoclast failure. Approximately 50% of the patients harbor mutations of the ATP6i gene, encoding for the osteoclast-specific a3 subunit of V-ATPase. We found inactivating ATP6i mutations in four patients, and three of these were novel. Patients shared macrocephaly, growth retardation and optic nerve alteration, osteosclerotic and endobone patterns, and high alkaline phosphatase and parathyroid hormone levels. Bone biopsies revealed primary spongiosa lined with active osteoblasts and high numbers of tartrate-resistant acid phosphatase (TRAP)-positive, a3 subunit-negative, morphologically unremarkable osteoclasts, some of which located in shallow Howship lacunae. Scarce hematopoietic cells and abundant fibrous tissue containing TRAP-positive putative osteoclast precursors were noted. In vitro osteoclasts were a3-negative, morphologically normal, with prominent clear zones and actin rings, and TRAP activity more elevated than in control patients. Podosomes, alphaVbeta3 receptor, c-Src, and PYK2 were unremarkable. Consistent with the finding in the bone biopsies, these cells excavated pits faintly stained with toluidine blue, indicating inefficient bone resorption. Bone marrow transplantation was successful in all patients, and posttransplant osteoclasts showed rescue of a3 subunit immunoreactivity. 相似文献
35.
George Capone Mary Stephens Stephanie Santoro Brian Chicoine Peter Bulova Moya Peterson Joan Jasien Anna Jo Smith Down Syndrome Medical Interest Group Adult Health Workgroup 《American journal of medical genetics. Part A》2020,182(7):1832-1845
Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed. 相似文献
36.
Enhanced Phagocytosis and Bactericidal Activity of Hepatic Reticuloendothelial System During Endotoxin Tolerance 总被引:1,自引:3,他引:1
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Giuseppe Ruggiero Augusto Andreana Riccardo Utili Domenico Galante 《Infection and immunity》1980,27(3):798-803
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
37.
Expression of the Bovine Leukemia Virus Envelope Glycoprotein (gp51) by Recombinant Baculovirus and Its Use in an Enzyme-Linked Immunosorbent Assay
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Antonio De Giuseppe Francesco Feliziani Domenico Rutili Gian Mario De Mia 《Clinical and Vaccine Immunology : CVI》2004,11(1):147-151
The gene encoding the major envelope glycoprotein (gp51) with its signal sequence, represented by an additional NH2-terminal 33-residue amino acid sequence of bovine leukemia virus (BLV), was inserted into a baculovirus transfer vector. A recombinant virus expressing a secreted gp51 protein in insect cells was isolated. The recombinant gp51 expressed was characterized by using an anti-BLV monoclonal antibody by both Western blotting analysis and enzyme-linked immunosorbent assay (ELISA). The secreted gp51 was used as an antigen, and an ELISA with recombinant gp51 (rgp51) was developed for the detection of BLV antibodies. This new procedure was compared with a previous ELISA method for the detection of BLV antibodies and an agar gel immunodiffusion test performed with an unpurified BLV antigen preparation. The comparative testing of field samples showed that the ELISA with rgp51 is more specific and also suitable for the testing of pooled sera. 相似文献
38.
Oumhani K Canossi A Piancatelli D Di Rocco M Del Beato T Liberatore G Aureli A Benjoaud A El Aouad R Adorno D Casciani CU Ben Jouad AE 《Human immunology》2002,63(2):129-138
To examine the genetic diversity in Morocco, the polymorphism at the HLA-DRB1 locus was investigated in two populations: the Metalsa group consisting of Berbers from north Morocco (who speak the Tarifit language and live in the Nador area), and the Chaouya group who are Arabic-speaking people from west Morocco (Atlantic coast) living in the Settat area. The DRB1 alleles of 197 healthy unrelated individuals were identified by direct DNA sequencing of exon 2 using fluorescently-labeled primers. A total of 28 and 29 alleles at DRB1 locus were identified in the Metalsa and Chaouya groups, respectively. The most frequent alleles in the Metalsa group are DRB1*03011 (20.2%), DRB1*0701 (12.12%), and DRB1*1302 (11.11%). In the Chaouya group, DRB1*0701 (16.33%), DRB1*15011 (12.76%), and DRB1*03011 (11.73%) are most common. Each population exhibits some specific variants and some uncommon alleles. The frequency of the DRB1*03011 allele differs significantly between the two populations (p = 0.0311). The DRB1 frequency distributions in the two groups suggest the effects of balancing selection. The interpopulation analysis highlighted a strong relatedness, based on genetic distances, between the two Moroccan groups and the other north Africans (the Moroccans from El Jadida area, Moroccan Souss Berbers, Algerians, and Tunisians), and to a lesser extent with the Iberians, French, and Ethiopians. 相似文献
39.
Massimiliano Valeriani Domenico Restuccia Vincenzo Di Lazzaro Domenica Le Pera Carmen Barba Pietro Tonali François Mauguiere 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(3):306-315
Brain electrical source analysis (BESA) of the scalp electroencephalographic activity is well adapted to distinguish neighbouring
cerebral generators precisely. Therefore, we performed dipolar source modelling in scalp medium nerve somatosensory evoked
potentials (SEPs) recorded at 1.5-Hz stimulation rate, where all the early components should be identifiable. We built a four-dipole
model, which was issued from the grand average, and applied it also to recordings from single individuals. Our model included
a dipole at the base of the skull and three other perirolandic dipoles. The first of the latter dipoles was tangentially oriented
and was active at the same latencies as the N20/P20 potential and, with opposite polarity, the P24/N24 response. The second
perirolandic dipole showed an initial peak of activity slightly earlier than that of the N20/P20 dipolar source and, later,
it was active at the same latency as the central P22 potential. Lastly, the third perirolandic dipole exaplaining the fronto-central
N30 potential scalp distribution was constantly more posterior than the first one. In order to evaluate the effect of an increasing
repetition frequency on the activity of SEP dipolar sources, we applied the model built from 1.5-Hz SEPs to traces recorded
at 3-Hz and 10-Hz repetition rates. We found that the 10-Hz stimulus frequency reduced selectively the later of the two activity
phases of the first perirolandic dipole. The decrement in strength of this dipolar source can be explained if we assume that:
(a) the later activity of the first perirolandic dipole can represent the inhibitory phase of a “primary response”; (b) two
different clusters of cells generate the opposite activities of the tangential perirolandic dipole. An additional finding
in our model was that two different perirolandic dipoles contribute to the centro-parietal N20 potential generation.
Received: 5 August 1997 / Accepted: 26 November 1997 相似文献
40.
Domenico Schiavino Eleonora Nucera Emanuela Pollastrini Tiziana De Pasquale Alessandro Buonomo Francesco Bartolozzi Carla Lombardo Chiara Roncallo Giampiero Patriarca 《Annals of allergy, asthma & immunology》2004,92(4):409-413
BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers. 相似文献