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91.
92.
The development of Babesia equi in salivary glands of adult female Boophilus microplus was observed under a light microscope using semithin sections stained with toluidine blue. Engorged nymphs were obtained
from splenectomized foals experimentally infected with B. equi. As adults, they were then fed on rabbits for 5 days and the salivary glands of manually collected individuals were removed
at intervals of 24 h. Sporozoites were found in type III granular acini cells between the 2nd and 5th days following feeding
on the rabbits. Sporoblasts and sporozoites were observed in the same or adjacent acini cells in all the glands examined.
The formation of the sporozoites occurred following the multiple division of the sporoblasts through a process of radial budding
from the periphery of bodies resulting from multiple fission. Sporozoites were detected in smears of adult males stained with
Giemsa, between the 2nd and 5th days following feeding by the ticks. Adults of B. microplus, fed during the nymphal phase on foals with patent parasitemia, transmitted sporozoites of B. equi to a splenectomized foal. The role of B. microplus in the transmission and epidemiology of B. equi is discussed.
Received: 16 June 1997 / Accepted: 2 September 1997 相似文献
93.
94.
Bruna Velasques Sergio Machado Cláudio Elidio Portella Julio Guilherme Silva Luis F.H. Basile Mauricio Cagy Roberto Piedade Pedro Ribeiro 《Neuroscience letters》2007
The present experiment aimed at investigating electrophysiologic changes observed as beta band asymmetry, by Quantitative Electroencephalography (qEEG), when individuals performed a reaching motor task (catching a ball in free fall). The sample was composed of 23 healthy individuals, of both sexes, with ages varying between 25 and 40 years old. All the subjects were right handed. A two-way ANOVA was applied for the statistical analysis, to verify the interaction between task moment (i.e., 2 s before and 2 s after ball's fall) and electrode (i.e., frontal, central and temporal regions). The first analysis compared electrodes placed over the somatosensory cortex. Central sites (C3–C4) were compared with temporal regions (T3–T4). The results showed a main effect for moment and position. The second analysis was focused over the premotor cortex, which was represented by the electrodes placed on the frontal sites (F3–F4 versus F7–F8), and a main effect was observed for position. Taken together, these results show a pattern of asymmetry in the somatosensory cortex, associated with a preparatory mechanism when individuals have to catch an object during free fall. With respect to task moment, after the ball's fall, the asymmetry was reduced. Moreover, the difference in asymmetry between the observed regions were related to a supposed specialization of areas (i.e., temporal and central). The temporal region was associated with cognitive processes involved in the motor action (i.e., explicit knowledge). On the other hand, the central sites were related to the motor control mechanisms per se (i.e., implicit knowledge). The premotor cortex, represented by two frontal regions (i.e., F3–F4 versus F7–F8), showed a decrease on neural activity in the contralateral hemisphere (i.e., to the right hand). This result is in agreement with other experiments suggesting a participation of the frontal cortex in the planning of the apprehension task. This sensorimotor paradigm may contribute to the repertoire of tasks used to study clinical conditions such as depression, alzheimer and Parkinson diseases. 相似文献
95.
Tyrer P Thompson S Schmidt U Jones V Knapp M Davidson K Catalan J Airlie J Baxter S Byford S Byrne G Cameron S Caplan R Cooper S Ferguson B Freeman C Frost S Godley J Greenshields J Henderson J Holden N Keech P Kim L Logan K Manley C MacLeod A Murphy R Patience L Ramsay L De Munroz S Scott J Seivewright H Sivakumar K Tata P Thornton S Ukoumunne OC Wessely S 《Psychological medicine》2003,33(6):969-976
BACKGROUND: We carried out a large randomized trial of a brief form of cognitive therapy, manual-assisted cognitive behaviour therapy (MACT) versus treatment as usual (TAU) for deliberate self-harm. METHOD: Patients presenting with recurrent deliberate self-harm in five centres were randomized to either MACT or (TAU) and followed up over 1 year. MACT patients received a booklet based on cognitive behaviour therapy (CBT) principles and were offered up to five plus two booster sessions of CBT from a therapist in the first 3 months of the study. Ratings of parasuicide risk, anxiety, depression, social functioning and global function, positive and negative thinking, and quality of life were measured at baseline and after 6 and 12 months. RESULTS: Four hundred and eighty patients were randomized. Sixty per cent of the MACT group had both the booklet and CBT sessions. There were seven suicides, five in the TAU group. The main outcome measure, the proportion of those repeating deliberate self-harm in the 12 months of the study, showed no significant difference between those treated with MACT (39%) and treatment as usual (46%) (OR 0.78, 95% CI 0.53 to 1.14, P=0.20). CONCLUSION: Brief cognitive behaviour therapy is of limited efficacy in reducing self-harm repetition, but the findings taken in conjunctin with the economic evaluation (Byford et al. 2003) indicate superiority of MACT over TAU in terms of cost and effectiveness combined. 相似文献
96.
Non-secretion of mutant proteins of the glaucoma gene myocilin in cultured trabecular meshwork cells and in aqueous humor 总被引:11,自引:0,他引:11
Jacobson N Andrews M Shepard AR Nishimura D Searby C Fingert JH Hageman G Mullins R Davidson BL Kwon YH Alward WL Stone EM Clark AF Sheffield VC 《Human molecular genetics》2001,10(2):117-125
Until recently, very little was known about the molecular mechanisms responsible for the development of glaucoma, a leading cause of blindness worldwide. Mutations in the glaucoma gene myocilin (MYOC, GLC1A) are associated with elevated intraocular pressure and the development of autosomal dominant juvenile glaucoma and a subset of adult-onset glaucoma. MYOC is expressed in the trabecular meshwork (TM), a tissue responsible for drainage of aqueous humor from the eye, and the tissue involved in elevated intraocular pressure associated with glaucoma. To better understand the role of MYOC in glaucoma pathogenesis, we examined the expression of normal and mutant myocilin in cultured ocular (TM) and non-ocular cells as well as in the aqueous humor of patients with and without MYOC glaucoma. Normal myocilin was secreted from cultured cells, but very little to no myocilin was secreted from cells expressing five different mutant forms of MYOC. In addition, no mutant myocilin was detected in the aqueous humor of patients harboring a nonsense MYOC mutation (Q368X). Co-transfection of cultured cells with normal and mutant myocilin led to suppression of normal myocilin secretion. These studies suggest that MYOC glaucoma is due either to insufficient levels of secreted myocilin or to compromised TM cell function caused by congestion of the TM secretory pathway. 相似文献
97.
The present study has been designed to: (1) evaluate the adequacy of a psychosocial-appraisal health model posited to explain the decision-making processes associated with the intention as well as the (non)practice of protective behaviours; and (2) test for sex differences in the hypothesized structural relations (both direct and indirect) between the model's exogenous (psychosocial) and endogenous (cognitive appraisal) factors in representing the way health decisions are made. Results obtained from path analysis (N=1269) provided overall support for the 'fit' of the hypothesized health model. The implications of the findings with regard to differences in male and female health status are discussed. 相似文献
98.
Bacterial Clearance and Cytokine Profiles in a Murine Model of Postsurgical Nosocomial Pneumonia 下载免费PDF全文
Patricia A. Manderscheid Ryan P. Bodkin Bruce A. Davidson Erik Jensen Thomas A. Russo Paul R. Knight 《Clinical and Vaccine Immunology : CVI》2004,11(4):742-751
The development of a nosocomial pneumonia is facilitated by alterations in host innate pulmonary antibacterial defenses following surgical trauma, which can result in decreased pulmonary bacterial clearance and increased morbidity and mortality. In a murine model of postoperative nosocomial infection, surgical stress (laparotomy) decreased Escherichia coli clearance from the lungs of animals that underwent surgery. Consistent with previous studies, (i) pulmonary levels of tumor necrosis factor alpha at 6 h and of interleukin-1β (IL-1β), IL-6, and gamma interferon (IFN-γ) at 24 h post-bacterial infection (PBI) were decreased in animals that underwent laparotomy 24 h prior to E. coli infection (LAP/E. coli) compared to animals that received E. coli only; (ii) KC and macrophage inhibitory protein 2 were elevated at 6 h PBI in LAP/E. coli animals compared to E. coli-only animals; however, at 24 h PBI, levels were higher in the E. coli-only group; (iii) at 24 h PBI, monocyte chemoattractant protein 1 was lower in the LAP/E. coli group compared to the E. coli-only group; (iv) IL-10 levels were unaffected at all time points evaluated; and (v) the total number of neutrophils present in the lungs of LAP/E. coli animals at 6 h PBI was decreased in comparison to that in E. coli-only animals, resulting in decreased bacterial clearance and increased mortality in LAP/E. coli animals by 24 h PBI. Similar changes in cytokine profiles, pulmonary bacterial clearance, and mortality were consistent with reported findings in patients following surgical trauma. This model, therefore, provides a clinically relevant system in which the molecular and cellular mechanisms that lead to the development of nosocomial pneumonia can be further explored. 相似文献
99.
The fragile X chromosome, associated with a common form of X-linked mental retardation, is cytologically observed most often as a gap or fragile site near the distal end of the long arm in band Xq28. Expression of this site is variable and dependent upon lowered thymidylate pools. In order to examine the behavior of this fragile site in a foreign genetic background, interspecific somatic cell hybrids were isolated from crosses of hamster cells and lymphoblastoid cells derived from male patients with fragile X-linked mental retardation. Three hybrid cell lines containing the human X chromosome were analyzed. Following induction with 5-fluorodeoxyuridine, all three hybrids expressed the fragile site in approximately 10% of the metaphases examined. Our data indicate that expression of the fragile site in band Xq27 is dependent neither on the integrity of the human genome nor on the expression of human autosomal genes. 相似文献
100.
Balbo SL Mathias PC Bonfleur ML Alves HF Siroti FJ Monteiro OG Ribeiro FB Souza AC 《Research communications in molecular pathology and pharmacology》2000,108(5-6):291-296
In order to study the role of vagus nerve activity at the onset of obesity induced by monosodium glutamate (MSG), 30-day-old MSG-rats were vagotomized or sham operated. Body weight and food intake were recorded until animals were 90 days old and then sacrificed. Naso-anal length was recorded for all animals. Periepididymal and retroperitoneal fat pads were isolated and weighed. Reduction of body weight and naso-anal length were registered in 30-day-old MSG-rats. Obesity could also be observed, as increase of Lee index indicated. Results were most evident in 90-day-old MSG-rats. In both groups neither body weight gain nor food intake was changed by vagotomy. However, fat accumulation on tissues was reduced by vagotomy in MSG-rats. The results showed that MSG-obesity is not related to an increment in food intake behavior. Vagotonia might play a role at the onset of MSG-obesity. 相似文献