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311.
The purpose of this study was to assess the possible correlation between Brucella and HIV infections. Iran is a country where HIV infection is expanding and Brucellosis is prevalent. In the present study, 184 HIV infected patients were assigned and for all of them HIV infection was confirmed by western blot test. In order to identify the prevalence rate of Brucella infection and systemic brucellosis in these subjects, sera samples were obtained and Brucella specific serological tests were performed to reveal antibody titers. Detailed history was taken and physical examination was carried out for all of patients. 11 (6%) subjects had high titers but only 3 of them were symptomatic. Most of these subjects were injection drug user (IDU) men and one was a rural woman. Considering both prevalence rates of Brucella infection (3%) and symptomatic brucellosis (0.1%) in Iran, our HIV positive patients show higher rates of Brucella infection and systemic brucellosis. Preserved cellular immunity of participants and retention of granulocytes activity may explain this poor association; whereas other explanations such as immunological state difference and non-overlapping geographical distribution of the 2 pathogens have been mentioned by various authors.  相似文献   
312.
Recent studies have determined that low sexual desire affects between one quarter to one third of adult premenopausal women, leading to distress. The prevalence of distress from low desire may suggest management gaps in the clinicians managing these patients, as recent studies have shown a reluctance to discuss sexual concerns. A survey based on the Theory of Planned Behavior, a predictive model linking attitudes and behavior, was designed to determine what factors influenced behavioral intent and behavior of nurse practitioners and physician assistants when managing decreased sexual desire and sexual concerns in premenopausal women. A path analysis found that attitudes and subjective norms were associated with behavioral intent in both groups and explained roughly one third of the intent to initiate a discussion about sexual health. In general, nurse practitioners and physician assistants had positive attitudes toward managing sexual concerns in female patients but were still at times reluctant to initiate sexual health discussions. This study shows that increased education is needed on female sexual dysfunction in the allied health professional community, as well as techniques for communicating with patients about their sexual concerns.  相似文献   
313.
The visual cortex of cats is highly evolved. Analogously to the brains of primates, large numbers of visual areas are arranged hierarchically and can be parsed into separate dorsal and ventral streams for object recognition and visuospatial representation. Within early primate visual areas, V1 and V2, and to a lesser extent V3, the two streams are relatively segregated and relayed in parallel to higher order cortex, although there is some evidence suggesting an alignment of V2 and V3 to one stream over the other. For cats, there is no evidence of anatomical segregation in areas 18 and 19, the analogs to V2 and V3. However, previous work was only qualitative in nature. Here we re-examined the feedback connectivity patterns of areas 18/19 in quantitative detail. To accomplish this, we used a genetically modified rabies virus that acts as a retrograde tracer and fills neurons with fluorescent protein. After injections into area 19, many more neurons were labeled in putative ventral stream area 21a than in putative dorsal stream region posterolateral suprasylvian complex of areas (PLS), and the dendrites of neurons in 21a were significantly more complex. Conversely, area 18 injections labeled more neurons in PLS, and these were more complex than neurons in 21a. We infer from our results that area 19 in cat is more aligned to the ventral stream and area 18 to the dorsal stream. Based on the success of our approach, we suggest that this method could be applied to resolve similar issues related to primate V3.  相似文献   
314.
Lung immunopathology is the main cause of influenza-mediated morbidity and death, and much of its molecular mechanisms remain unclear. Whereas tumor necrosis factor-α (TNF-α) is traditionally considered a proinflammatory cytokine, its role in influenza immunopathology is unresolved. We have investigated this issue by using a model of acute H1N1 influenza infection established in wild-type and TNF-α-deficient mice and evaluated lung viral clearance, inflammatory responses, and immunopathology. Whereas TNF-α was up-regulated in the lung after influenza infection, it was not required for normal influenza viral clearance. However, TNF-α deficiency led not only to a greater extent of illness but also to heightened lung immunopathology and tissue remodeling. The severe lung immunopathology was associated with increased inflammatory cell infiltration, anti-influenza adaptive immune responses, and expression of cytokines such as monocyte chemoattractant protein-1 (MCP-1) and fibrotic growth factor, TGF-β1. Thus, in vivo neutralization of MCP-1 markedly attenuated lung immunopathology and blunted TGF-β1 production following influenza infection in these hosts. On the other hand, in vivo transgenic expression of MCP-1 worsened lung immunopathology following influenza infection in wild-type hosts. Thus, TNF-α is dispensable for influenza clearance; however, different from the traditional belief, this cytokine is critically required for negatively regulating the extent of lung immunopathology during acute influenza infection.  相似文献   
315.
The effects of low-level lasers on bone cellular activity, bone structures, bone healing, fibroblasts activity and inflammation process have already been investigated. Considering orthodontic tooth movement, which is a complicated inflammatory process involving simultaneous bone apposition and resorption, the aim of this controlled study is to investigate the quantitative effects of a pulsed 850 nm laser (Optodan) and a continuous 630 nm laser (KLO3) on the orthodontic tooth movement in rabbits. This experimental study was conducted on 18 male albino rabbits divided into three equal groups of control, Optodan and KLO3. In all the groups, NiTi-closed coil springs were used on the first mandibular molars with 4-oz tension. The control group was not irradiated by laser, but the teeth in the laser groups were irradiated 9 days according to the periodontal therapeutic protocols. After 16 days, samples were sacrificed. The distance between the distal surface of the first molar and the mesial surface of the second molar was measured with 0.05-mm accuracy. The data were subjected to the statistical tests of Kolmogrov Smirnov and variance analysis. The mean orthodontic tooth movements of the first mandibular molars were 1.7 ± 0.16 mm in control group, 0.69 ± 0.16 mm in Optodan group and 0.86 ± 0.13 mm in KLO3 group. There were statistically significant difference between the control and the two other laser-irradiated groups (P < 0.001). The findings of the present study imply that the amounts of orthodontic tooth movement, after low-level laser therapy, are diminished. It could not be concluded that any low-level laser will reduce the speed of teeth movement in orthodontic treatments, and further studies with less or more energies may show different results.  相似文献   
316.
Dentine hypersensitivity has of long been known to be a common clinical problem in dental practices. Lasers have recently come to play a prominent role in the treatment of this disorder. They might, however, cause dental pulp damage. This study was conducted to evaluate the effect of Nd:yttrium-aluminum-garnet (YAG) laser on partial oxygen saturation of pulpal blood in sensitive anterior teeth. In this clinical trial, 65 hypersensitive teeth were selected and randomly allocated to two groups. The study group involved Nd:YAG laser treatment, while no treatment was employed for the control group. Using a pulse oximetry system, evaluations were preformed of the partial oxygen saturation in the pulpal blood before, immediately after, 1 week after, and 1 month after the treatment. The results were analyzed using the SPSS software and repeated-measures analysis of variance and paired-samples t tests. The mean partial oxygen saturation of the blood was found to be 85.4% in the study group, which was not significantly different from that of the control group. No significant differences were observed in the control group between the means obtained from pretreatment and post-treatment intervals (P > 0.05). The Post-treatment partial oxygen saturation mean rose to 89.3% (P = 0.001) and remained constant throughout the following week after it. However, no significant differences were found between the pretreatment partial oxygen saturation mean and the same measurement 1 month after treatment (P = 0.702). Nd:YAG laser therapy for dentine desensitization of anterior teeth caused no persistent changes in the partial oxygen saturation of pulpal blood. It may, therefore, be concluded that the diffusion of heat induced by the Nd:YAG laser into the pulp within the limit of the desensitization parameters cause no irreversible damages in the dental pulp.  相似文献   
317.
318.
Myelitis, including longitudinally extensive transverse myelitis (LTEM), is reported in more than forty patients after coronavirus disease 2019 (COVID-19). Among COVID-19 vaccines, only Oxford-AstraZeneca COVID-19 vaccine (AZD1222) has been associated with few cases of myelitis (1 LTEM). We report the first case of myelitis/LTEM after BBIBP-CorV/Sinopharm vaccine, interestingly presented as a hemicord syndrome. A 71-year-old male presented with left-side diplegia, right-side hemihyposthesis with facial sparing and impaired position sensation in left foot after vaccination with BBIBP-CorV. MRI revealed a longitudinal signal in left cervical hemicord. This is the first reported myelitis and LTEM with COVID-19 vaccines other than AZD1222.  相似文献   
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