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991.
992.
Several in vitro and in vivo models have revealed the key role of CXCR4/CXCL12 axis in tumor-stroma interactions. Stromal cells present in the tumor microenvironment express high levels of CXCL12 protein, directly stimulating proliferation and migration of CXCR4-expressing cancer cells. This specific prosurvival influence of stromal cells on tumor cells is thought to protect them from cytotoxic chemotherapy and is postulated as a possible explanation for the minimal residual disease in hematological and solid cancers. Therefore, CXCR4/CXCL12 signaling is an attractive therapeutic target in cancer, as proven in preclinical leukemia mouse models, where CXCR4 inhibition sensitized cancer cells to conventional chemotherapy. This study investigates whether inhibition of CXCR4 with the specific inhibitor AMD3100 sensitizes human prostate cancer cells to docetaxel. We showed that both mouse and human stromal cell lines have a protective effect on PC3-luc cells by promoting their survival after chemotherapy. Furthermore, we demonstrated that AMD3100 sensitizes PC3-luc cells to docetaxel. In a subcutaneous xenograft mouse model of human prostate carcinoma, we showed that a combination of docetaxel and AMD3100 exerts increased antitumor effect compared with docetaxel alone. We concluded that CXCR4 inhibition chemosensitizes prostate cancer cells, both in vitro and in vivo. To explore the relevance of these findings, we analyzed CXCR4 expression levels in human prostate cancer samples. We found that cancer cells present in bone metastatic lesions express higher CXCR4 levels relative to the cells present in primary tumors and lymph node metastatic lesions. These findings underscore the potential of CXCR4 inhibitors as chemosensitizing agents.  相似文献   
993.

Background  

Patients with juvenile dermatomyositis (JDM) often present strong exercise intolerance and muscle weakness. However, the role of exercise training in this disease has not been investigated.  相似文献   
994.
Objective: To ascertain that antibiotics have no role in the management of bronchiolitis. Design: Multicentre randomized control trial (RCT). Setting: Five purposively selected teaching hospitals in Bangladesh. Patient: Children under 24 months old with bronchiolitis. Interventions: Children were randomized into three groups of therapeutic interventions: parenteral ampicillin (P‐Ab), oral erythromycin (O‐Ab) and no antibiotic (N‐Ab) in adjunct to supportive measures. Main outcome measures: Clinical improvement was assessed using 18 symptoms/signs which were graded on a two‐point recovery scale of ‘rapid’ and ‘gradual’, indicating improvement within ‘four days’ and ‘beyond four days’, respectively. Results: Each intervention group consisted of 98 ± 1 children having comparable clinico‐epidemiological characteristics at the baseline. The trial revealed that most chesty features (features appearing to arise from chest, i.e. cough, breathing difficulty, wheeze, chest indrawing, tachypnoea, tachycardia, rhonchi and crepitation) demonstrated a gradual recovery, beyond 4th admission day and, not differing among the three intervention groups (p > 0.23, p < 0.62, p = 0.54, p < 0.27, p = 0.75, p = 0.76, p = 0.81, p > 0.98, respectively). Most non‐chesty features (features appearing to arise away from chest, i.e. feeding/sleeping difficulties, social smile, restlessness, inconsolable crying, nasal flaring, fever and hypoxaemia) demonstrated a rapid recovery, within 4 days, remaining comparable among the three intervention groups (p < 0.07, p = 0.65, p = 0.24, p < 0.61, p = 0.22, p = 0.84, p = 0.29 and p = 0.96, respectively). However, nasal symptoms (runny nose and nasal blockage) also showed no difference among groups (p = 0.36 and p = 0.66, respectively). Thus, the dynamics of clinical outcome obviates that children not receiving antibiotics had similar clinical outcome than those who did. Conclusion: In hospital settings, managing bronchiolitis with only supportive measures but without antibiotics remains preferable.  相似文献   
995.
Attention and memory deficits are among the most prominent cognitive disturbances observed in schizophrenia. It has been suggested that a disruption in anatomical connectivity between areas involved in attentional control might be responsible for these abnormalities. We used Diffusion Tensor Tractography and Color Stroop/Negative Priming(NP) paradigm to investigate integrity of the Cingulum Bundle(CB), the main white matter tract interconnecting these regions, and its relationship with executive functions in patients with schizophrenia and matched controls. The Fractional Anisotropy(FA), was calculated along the CB pathways, and correlated with reaction times for each Stroop item, and both Stroop, and NP effects. Patients with schizophrenia demonstrated decreased CB integrity and diminished NP effect, compared with controls, but both groups showed Stroop effect. For patients only, reaction times for every item, as well as for Stroop effect, correlated with left CB FA. These findings suggest that CB integrity disruptions might compromise the executive processes in schizophrenia.  相似文献   
996.
BACKGROUND: Psoralen ultraviolet A (PUVA) bath photochemotherapy has been proved highly effective in the treatment of various dermatoses without potential side-effects of systemic therapy. Another form of topical PUVA therapy (PUVA cream) without the logistical requirements for bath tubs has recently been developed. OBJECTIVE: We sought to develop preparation and treatment standards to PUVA cream and to confirm its clinical efficacy in the treatment of various dermatoses. METHODS: In the first phase, the safety of a novel cream containing 0.002% 8-methoxypsoralen (8-MOP) was determined in six healthy volunteers. In a second phase, 40 patients with different dermatoses were treated with a minor concentration (0.001% 8-MOP), following the guidelines for topical PUVA of the British Photodermatology Group. RESULTS: Plasma levels of psoralen after the application of the novel cream containing 0.002% 8-MOP, were less than 34 ng/mL, the maximum 8-MOP concentration reported for topical PUVA. With a minor concentration (0.001% 8-MOP), important improvement or healing was found in 53.3% of the cycles, generally with a good response since the first month of treatment. Only mild side-effects were detected in 14 patients. CONCLUSIONS: Based on our data, PUVA cream photochemotherapy is well accepted by patients and may be a highly effective treatment even if previous therapy was unsuccessful. In addition, PUVA cream is easier to use than PUVA bath.  相似文献   
997.
998.
Migraine with aura (MA) is associated with cerebral hyper- and hypoperfusion during and after the attacks. Several attempts to estimate individual perfusion changes and asymmetries in patients with MA using transcranial Doppler (TCD) have not been consistent. In 70 patients with MA and 40 controls with migraine without aura (MoA) or without any history of migraine, interictally recorded TCD sequences were prospectively analysed. Formal curve analysis of the visually evoked flow response (VEFR) was performed semiautomatically. As a main parameter for functional vasomotor reactivity (fVMR), the visually evoked flow rate (VEFR%) was calculated. The VEFR% showed a significantly higher mean difference of 14.7 ± 12% in MA patients vs. 5.8 ± 4.4% ( P  < 0.001) in controls. The significant asymmetry of fVMR in MA patients is suggested to reflect interattack persisting vasomotor changes which are of pathophysiological interest and may be used as a monitoring tool under prophylactic medication.  相似文献   
999.
BACKGROUND: The caudate nucleus might contribute to the psychopathological and cognitive deficits observed in schizotypal personality disorder (SPD), a schizophrenia spectrum disorder. Here we focused on female patients, because this group is underrepresented in studies of SPD and schizophrenia, and we might learn more about the caudate and clinical and cognitive impairments that are unique to female patients diagnosed with SPD. METHODS: Magnetic resonance imaging scans, obtained on a 1.5-T magnet with 1.5-mm contiguous slices, were used to measure the caudate in 32 neuroleptic-na?ve women with SPD and in 29 female normal comparison subjects. Subjects were group-matched for age, parental socioeconomic status, and intelligence quotient. RESULTS: We found significantly reduced left and right caudate relative volume (8.3%, 7.7%) in female SPD subjects compared with normal comparison subjects. In female SPD subjects, we found significant correlations between smaller total caudate relative volume and worse performance on the Wisconsin Card Sorting test (nonperseverative errors) and on the California Verbal Learning Test (verbal memory and learning), and significant correlations between smaller total caudate relative volume and both positive and negative symptoms on the Structured Interview for Schizotypy. CONCLUSIONS: These findings demonstrate that, for female SPD subjects, smaller caudate volume is associated with poorer cognitive performance and more schizotypal symptomatology.  相似文献   
1000.
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