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One of the fundamental properties of a neuronal circuit is the map of its connections. The cellular and developmental processes that allow for the growth of axons and dendrites, selection of synaptic targets, and formation of functional synapses use neuronal surface receptors and their interactions with other surface receptors, secreted ligands, and matrix molecules. Spatiotemporal regulation of the expression of these receptors and cues allows for specificity in the developmental pathways that wire stereotyped circuits. The families of molecules controlling axon guidance and synapse formation are generally conserved across animals, with some important exceptions, which have consequences for neuronal connectivity. Here, we summarize the distribution of such molecules across multiple taxa, with a focus on model organisms, evolutionary processes that led to the multitude of such molecules, and functional consequences for the diversification or loss of these receptors.  相似文献   
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OBJECTIVE: The purpose of this study was to evaluate the CT findings of pulmonary artery aneurysms in patients being treated for Beh?et's disease. MATERIALS AND METHODS: Thirteen patients with Beh?et's disease who had a total of 46 aneurysms were included in the study. All patients underwent helical CT before and after treatment. Both initial and follow-up CT scans were evaluated for location, number, and size of aneurysms and for thrombosis and pulmonary parenchyma changes. RESULTS: Thirty-five (76%) of the 46 aneurysms completely disappeared during the 3-42 months of treatment (mean, 21 months), and the remaining 11 aneurysms (24%) became smaller. Both disappearance and regression of aneurysms were preceded by thrombus formation. In 15 initially thrombosed aneurysms (33%), the thrombus increased in size during treatment. After treatment, the thrombus regressed and the pulmonary artery aneurysms disappeared. Thirty-one initially nonthrombosed aneurysms (67%) first became thrombosed during treatment; later, the thrombus regressed and the aneurysm decreased in size. Perianeurysmal consolidation and air-space nodules detected in seven patients disappeared in the early stages of treatment. Mosaic attenuation areas were seen in eight patients and disappeared in seven (88%) after treatment. CONCLUSION: Pulmonary artery aneurysms in Beh?et's disease may become smaller or disappear with medical treatment. Mural thrombotic changes may be observed during the regression of pulmonary artery aneurysms. Helical CT is helpful in the diagnosis and follow-up of aneurysms and thrombosis in Beh?et's disease.  相似文献   
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Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model.  相似文献   
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Purpose: The aim of the study was to investigate whether maternal serum TSP-1 level was associated with PE.

Materials and methods: In our case control study, 84 pregnant women in the third trimester were included. Forty-one of them were healthy and 43 of them were with the diagnosis of PE. The diagnosis was based on the definitions of the National High Blood Pressure Education Program working Group on High Blood Pressure in Pregnancy. Preeclamptic patients were divided into two subgroups as mild and severe. Blood pressure (BP) of pregnant women were obtained in left-side lying position using a mercury sphygmomanometer after at least 10 minutes of rest. Ten milliliters of venous blood was taken from every pregnant women and dispensed into lithium heparin and serum was obtained. Samples were stored at ?80?°C until analyzed. Serum TSP-1 level was measured using enzyme-linked immunosorbent assay (ELISA). All tests were two-tailed and p < .05 was considered to be statistically significant.

Results: TSP-1 level was significantly lower in PE group than in controls (p?=?.003). Platelet counts were similar in two groups (p = .26). TSP-1 levels were significantly lower in severe PE than in mild PE cases. According to the subgroup analysis, TSP-1 level was found significantly lower in severe preeclampsia group compared to control group (p = .015).

Conclusions: In light of the association between endothelial dysfunction and preeclampsia, we claim that lower levels of TSP-1 which is released mostly from endothelial cells seem to reflect disease severity in PE. Our study reveals that maternal serum TSP-1 levels decrease in pregnant women presenting with PE and TSP-1 may be a new biomarker for the detection of PE and even severity of it. Further studies especially prospective ones with greater numbers of cases are needed.  相似文献   
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Cisplatin is a widely used antineoplastic agent in the treatment of various cancers. Peripheral neuropathy is a well‐known side effect of cisplatin and has potential to result in limiting and/or reducing the dose, decreasing the quality of life. Thus, effective treatments are needed. Agmatine is an endogenous neuromodulator that has been shown to exert antiallodynic effects in various animal studies. The first aim of this study was to investigate the in vitro effects of agmatine on cisplatin‐induced neurotoxicity. Primary cultures of dorsal root ganglia (DRG) which are the primary target of drug injury were prepared. DRG cells were incubated with cisplatin (100, 200, 500 μm ). Then, agmatine (10, 100, 500 μm ) was administered with the submaximal concentration of cisplatin. Cisplatin caused concentration‐dependent neurotoxicity, and agmatine did not alter this effect. The second aim was to investigate the effects of agmatine on cisplatin‐induced peripheral neuropathy in rats and the influence of nitric oxide synthase (NOS) inhibitor, L‐NAME, in this effect. Female Sprague Dawley rats received intraperitoneal saline (control), cisplatin (3 mg/kg), cisplatin+agmatine (100 mg/kg), or cisplatin+agmatine+L‐NAME (10 mg/kg) once a week for 5 weeks. The mechanical allodynia, hot plate, and tail clip tests were performed, and DRG cells and sciatic nerves were analyzed. Agmatine and agmatine+L‐NAME combination attenuated CIS‐induced mechanical allodynia and degeneration in DRG cells and sciatic nerves. However, L‐NAME did not potentiate the antiallodynic or neuroprotective effect of agmatine. These findings indicate that agmatine co‐administration ameliorates cisplatin‐induced neuropathy and may be a therapeutic alternative.  相似文献   
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