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991.
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In this study, we examined whether melatonin treatment would increase new cell formation in the hippocampus in ovariectomized (OVX) mice. Chronic exogenous melatonin administration increased bromodeoxyuridine (BrdU) (OVX-sham 72 ± 3.2 versus OVX-mel 122 ± 12.0; P < 0.05) and doublecortin (DCX) (OVX-sham 88 ± 3.1 versus OVX-mel 176 ± 9.9; P < 0.05) immunoreactive cells in the hippocampus of ovariectomized mice. This neuronal development was correlated with synaptic plasticity, identified using the Golgi impregnation method to quantify dendritic spines in mouse dentate gyrus (DG). Finally, the antidepressant-like state of the animals was evaluated by the tail suspension test. The results indicate that melatonin acts on birth, survival, and differentiation of new neurons in the hippocampus, stimulates maturation of spines, and exerts an antidepressant-like action under estrogen-deprived conditions, in both a strain- and gender-independent manner, suggesting that this indoleamine may be useful in improving brain functions.  相似文献   
994.
We present the angiograms of a patient after transmyocardial laser revascularization (TMR), which were performed 10 years before by the application of holmium laser pulses. Thirteen years before the TMR procedure, the patient underwent coronary artery bypass graftings complicated by graft occlusion with no longer possibility of direct revascularization. Then, refractive angina required an alternative approach for symptom relief as the indirect revascularization by the application of the holmium laser pulses. Interestingly, the late angiograms, taken when the patient suffered from effort dyspnea for ongoing left ventricular dysfunction, showed a network of small vessels (absent before the TMR procedure) that supplies blood to the heart with no flow through the coronary arteries because of their complete occlusion. This is a historical presentation of the results of TMR to understand the effects of the indirect revascularization on the blood circulation through the heart over the long-term follow-up.  相似文献   
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996.

OBJECTIVE

Metformin is associated with reduced cancer-related morbidity and mortality. The aim of this study was to assess the effect of metformin on cancer incidence in a consecutive series of insulin-treated patients.

RESEARCH DESIGN AND METHODS

A nested case-control study was performed in a cohort of 1,340 patients by sampling, for each case subject, age-, sex-, and BMI-matched control subjects from the same cohort.

RESULTS

During a median follow-up of 75.9 months, 112 case patients who developed incident cancer and were compared with 370 control subjects. A significantly lower proportion of case subjects were exposed to metformin and sulfonylureas. After adjustment for comorbidity, glargine, and total insulin doses, exposure to metformin, but not to sulfonylureas, was associated with reduced incidence of cancer (odds ratio 0.46 [95% CI 0.25–0.85], P = 0.014 and 0.75 [0.39–1.45], P = 0.40, respectively).

CONCLUSIONS

The reduction of cancer risk could be a further relevant reason for maintaining use of metformin in insulin-treated patients.Several studies have shown that metformin is associated with reduced cancer-related morbidity and mortality (14), due to improvement in insulin sensitivity (5) or to the activation of AMP-activated protein kinase (6). In insulin-treated patients, the reduction in insulin doses determined by metformin (7) could theoretically produce a decrease in cancer incidence.  相似文献   
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AIM:To compare long-term results of gastric cancer patients undergoing laparoscopic and open gastrec-tomy in a single unit.METHODS:From February 2000 to September 2004,all patients with adenocarcinoma of the stomach were assessed to entry in this longitudinal prospective non-randomized trial.Primary endpoint was cancer-related survival and secondary endpoints were overall survival,evaluation of surgical complications and mortality.RESULTS:Fifty-eight patients were enrolled.Forty-seven patients were followed...  相似文献   
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It is well known that viewing graspable tools (but not other objects) activates motor-related brain regions, but the time course of affordance processing has remained relatively unexplored. In this study, EEG was continuously recorded from 128 scalp sites in 15 right-handed university students while they received stimuli in the form of 150 pictures of familiar non-tool objects and 150 pictures of manipulable tools, matched for size, luminance and perceptual familiarity. To select the 300 images for the study, a wider set of preliminary stimuli was screened for motoric content by 20 judges using a 3-point scale (0 = absent; 2 = strong); pictures that scored below 1.5 or above 0.6 were excluded from the tool and non-tool categories, respectively. Tools and non-tools were presented in random order, interspersed with 25 photos of live plants. Each slide was presented for 1000 ms, with an interval ranging from 1500 to 1900 ms. The task consisted of responding to the photos of plants while ignoring the other stimuli. Both an anterior negativity (210-270 ms) and a centroparietal P300 (550-600 ms) were larger in response to tools than objects, particularly in the left hemisphere. swLORETA inverse solution identified the occipito-temporal cortex (BA19 and BA37) as the most significant source of activity (in the 210-270-ms time window) for both types of visual objects and the left postcentral gyrus (BA3) and the left and right premotor cortex (BA6) as the most significant source of activity for tools only. These data hint at an automatic access to motoric object properties even under conditions in which attention is devoted to other stimulus categories.  相似文献   
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