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61.
The patterns of exochorion ornaments on eggs of seven South American Lutzomyia sand fly species were analyzed by scanning electron microscopy (SEM): Lutzomyia (Lutzomyia) cruzi (Mangabeira 1938), Lutzomyia (Micropygomyia) evandroi (Costa Lima and Antunes 1936), L. (Nyssomyia) intermedia (Lutz and Neiva 1912), L. longipalpis (Lutz and Neiva 1912), L. migonei (Franca 1920), L. (Nyssomyia) neivai (Pinto 1926), and L. renei (Martins, Falcao, and Silva 1957). Different patterns were observed, which showed the distinction between some species. Egg ornaments in L. cruzi and L. longipalpis appear as single, parallel, unconnected ridges, whereas eggs of L. migonei appear as single, parallel, connected ridges. Eggs of L. (Nyssomyia) intermedia and L. (N.) neivai present a new variation of the single, unconnected, parallel ridges pattern: small tubercles are present, distributed between the ridges. Eggs of L. renei present an elliptical pattern, with most structures connected by straight ridges. Eggs of L. (M.) evandroi present a polygonal pattern, with alternate rows of small and large hexagons. Our data emphasize the advantages of the SEM approach in the study of the exochorion patterns of Lutzomyia eggs and in the distinction of the sand fly species.  相似文献   
62.
We used simultaneous multi-site neural ensemble recordings to investigate the representation of tactile information in three areas of the primate somatosensory cortex (areas 3b, SII and 2). Small neural ensembles (30-40 neurons) of broadly tuned somatosensory neurons were able to identify correctly the location of a single tactile stimulus on a single trial, almost simultaneously. Furthermore, each of these cortical areas could use different combinations of encoding strategies, such as mean firing rate (areas 3b and 2) or temporal patterns of ensemble firing (area SII), to represent the location of a tactile stimulus. Based on these results, we propose that ensembles of broadly tuned neurons, located in three distinct areas of the primate somatosensory cortex, obtain information about the location of a tactile stimulus almost concurrently.  相似文献   
63.
Monoclonal antibodies directed against the Thy-1 molecule or the CD3 complex were used to analyze the activation of T cells from mice acutely infected with Trypanosoma cruzi. When stimulated with G7, a mitogenic anti-Thy-1 monoclonal antibody, spleen cells from infected mice showed a markedly reduced or absent response that could not be restored by varying the culture time or the antibody concentration. However, cells from acutely infected animals proliferated to 145-2C11, an anti-CD3 monoclonal antibody. Flow cytometric analysis showed that the impaired response to G7 could not be attributed to a lack of expression of Thy-1 or CD3. Indeed, G7 seemed to deliver a positive signal to the cells since the proliferative response was completely restored by the addition of PMA. Moreover, purified T cells from infected mice responded to G7 in the presence of accessory cells from uninfected animals. These results suggest that a defective co-stimulatory cell function could be involved in the immunosuppression. In addition, our data present evidence against a generalized T cell anergy in the acute phase of the disease, since CD3-mediated activation was normal.  相似文献   
64.
Exploring an alternative to improve the clinical management of hypertension, we tested the hypothesis that food supplementation with coconut oil (EVCO), alone or combined with aerobic exercise training, could exert an antihypertensive effect (primary outcome) in patients with stage 1 hypertension. Forty-five hypertensive volunteers of both genders participated in a placebo-controlled clinical trial. The volunteers were submitted to 24-hour ambulatory blood pressure monitoring, analysis of blood pressure variability (BPV), measurement of serum malondialdehyde (MDA) and nutritional assessment. Results indicate that EVCO consumption had no adverse effects. The supplementation did not increase the caloric intake compared with placebo, and the dietary constituents were similar between groups, except for the saturated fats, especially lauric acid. The analysis of blood pressure indicated absence of antihypertensive effect of EVCO alone or combined with physical training. Furthermore, no effects on blood pressure variability and oxidative stress were observed in the supplemented hypertensive patients. Thus, despite the results observed in pre-clinical studies, the current clinical study did not provide evidence to support the use of coconut oil as an adjuvant in the management of hypertension in humans.  相似文献   
65.
Dry extracts from the Eurasian plants, Ajuga turkestanica, Eurycoma longifolia, and Urtica dioica have been used as anabolic supplements, despite the limited scientific data on these effects. To assess their actions on early sarcopenia signs, male and female castrated mice were supplemented with lyophilized extracts of the three plants, isolated or in association (named TLU), and submitted to resistance exercise. Ovariectomy (OVX) led to body weight increase and non-high-density cholesterol (HDL) cholesterol elevation, which had been restored by exercise plus U. dioica extract, or by exercise and TLU, respectively. Orchiectomy (ORX) caused skeletal muscle weight loss, accompanied by increased adiposity, being the latter parameter reduced by exercise plus E. longifolia or U. dioica extracts. General physical activity was improved by exercise plus herbal extracts in either OVX or ORX animals. Exercise combined with TLU improved resistance to fatigue in OVX animals, though A. turkestanica enhanced the grip strength in ORX mice. E. longifolia or TLU also reduced the ladder climbing time in ORX mice. Resistance exercise plus herbal extracts partly altered gastrocnemius fiber size frequencies in OVX or ORX mice. We provide novel data that tested ergogenic extracts, when combined with resistance exercise, improved early sarcopenia alterations in castrated male and female mice.  相似文献   
66.
Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in...  相似文献   
67.
Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial...  相似文献   
68.
Lasers in Medical Science - Physical activity raises body temperature. However, the literature does not contain studies about whether the employment of hotobiomodulation (PMB) could significantly...  相似文献   
69.
In peritoneal dialysis (PD), a cloudy dialysate is an alarming finding. Bacterial peritonitis is the most common cause, however, atypical infections and non‐infectious causes must be considered. A 46‐year‐old man presented with asthenia, paraesthesia, foamy urine and hypertension. Laboratory testing revealed severe azotaemia, anaemia, hyperkalaemia and nephrotic‐range proteinuria. Haemodialysis was started through a central venous catheter. Later, due to patient preference, a Tenckhoff catheter was inserted. Conversion to PD occurred 3 weeks later, during hospitalization for a presumed central line infection. A month later, the patient was hospitalized for neutropenic fever. He was diagnosed an acute parvovirus infection and was discharged under isoniazid for latent tuberculosis. Four months later, the patient presented with fever and a cloudy effluent. Peritoneal fluid (PF) cytology was suggestive of infectious peritonitis, but the symptoms persisted despite antibiotic therapy. Bacterial and mycological cultures were negative. No neoplastic cells were detected. Mycobacterium tuberculosis eventually grew in PF cultures, despite previous negative molecular tests. Directed therapy was then initiated with excellent response. Thus, facing a cloudy effluent, one must consider multiple aetiologies. Diagnosis of peritoneal tuberculosis is hampered by the lack of highly sensitive and specific exams. Here, diagnosis was only possible due to positive mycobacterial cultures.  相似文献   
70.
Intracranial subdural hematoma is a rare, but potentially lethal complication of neuraxial procedures. Considering the high frequency of neuraxial techniques in the obstetric population, parturients are more susceptible to this fearful complication. The diagnosis is often masked and delayed because it shares similar clinical characteristics with posdural puncture headache, with headache being the most common symptom. This case report describes a timely diagnosis and successful management of an intracranial subdural hematoma, after unintentional dural puncture during labour epidural analgesia. Postpartum headache following epidural analgesia, remains a clinical challenge for the caring team, requiring a close follow-up and awareness for non-benign causes that require prompt management, avoiding devastating consequences.  相似文献   
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