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61.
Metabolic parameters were determined in fasting blood serum, fasting first morning urine, and 24-hour urine of male patients with recurrent calcium oxalate stones (N = 26, age 39.1 +/- 6.2 years) as well as in male healthy controls (N = 18, age 35.0 +/- 7.1 years), recruited from the eastern part of Croatia. The 24-hour urinary calcium excretion was significantly higher (p < 0.01) for patients (5.6 +/- 2.5 mmol) than for controls (3.7 +/- 1.9 mmol), but potassium excretion was higher (p < 0.01) for controls (74.5 +/- 33.8 mmol) than for patients (49.2 +/- 15.7 mmol). The mean ionic activity product of calcium and oxalate ions, IAP(CaOx), calculated from the fasting first morning urine parameters, was 25% higher for patients than for controls, but the difference was not statistically significant (p > 0.05). Very strong correlation (r = 0.97) was obtained between IAP(CaOx) values and calculated Ogawa indices that were recommended for estimating the potential risk for calcium oxalate stone formation.  相似文献   
62.
Dissection of craniocervical arteries internal carotid artery (ICA), or vertebral artery (VA) is an increasingly recognized entity and infrequent cause of stroke. We investigated 8 patients (4 women and 4 men) with dissections of the craniocervical arteries. Diagnostic procedures for detection of craniocervical dissection included: extracranial ultrasound-color Doppler flow imaging (CDFI) of carotid and vertebral arteries, transcranial Doppler sonography (TCD) and radiological computed tomography (CT) and digital subtractive angiography (DSA) examinations. Ultrasound findings (CDFI of carotid and vertebral arteries) were positive for vessel dissection in seven patients (or 87.5 per cent) and negative in one patient. DSA was consistent with dissection in five patients (or 62.5 per cent), negative in one, while in two patients the examination was not performed due to known allergy to contrast media. Five patients (62.5 per cent) were treated with anticoagulants, one with suppressors of platelet aggregation, and two patients were operated. Six patients (75 per cent) after the treatment showed partial recovery of neurological defects, and an improvement of ultrasound finding of dissected arteries. In one patient, following operation, stroke developed with deterioration of motor deficit, and one patient was readmitted three months later due to a newly developed stroke and soon died. The diagnosis should be suspected in any young or middle-age patient with new onset of otherwise unexplained unremitting headache or neck ache, especially in association with transient or permanent focal neurological deficits.  相似文献   
63.
Insulin stimulates production of NO in vascular endothelium via activation of phosphatidylinositol (PI) 3-kinase, Akt, and endothelial NO synthase. We hypothesized that insulin resistance may cause imbalance between endothelial vasodilators and vasoconstrictors (e.g., NO and ET-1), leading to hypertension. Twelve-week-old male spontaneously hypertensive rats (SHR) were hypertensive and insulin resistant compared with control Wistar-Kyoto (WKY) rats (systolic blood pressure 202 +/- 11 vs. 132 +/- 10 mmHg; fasting plasma insulin 5 +/- 1 vs. 0.9 +/- 0.1 ng/ml; P < 0.001). In WKY rats, insulin stimulated dose-dependent relaxation of mesenteric arteries precontracted with norepinephrine (NE) ex vivo. This depended on intact endothelium and was blocked by genistein, wortmannin, or N(omega)-nitro-l-arginine methyl ester (inhibitors of tyrosine kinase, PI3-kinase, and NO synthases, respectively). Vasodilation in response to insulin (but not ACh) was impaired by 20% in SHR (vs. WKY, P < 0.005). Preincubation of arteries with insulin significantly reduced the contractile effect of NE by 20% in WKY but not SHR rats. In SHR, the effect of insulin to reduce NE-mediated vasoconstriction became evident when insulin pretreatment was accompanied by ET-1 receptor blockade (BQ-123, BQ-788). Similar results were observed during treatment with the MEK inhibitor PD-98059. In addition, insulin-stimulated secretion of ET-1 from primary endothelial cells was significantly reduced by pretreatment of cells with PD-98059 (but not wortmannin). We conclude that insulin resistance in SHR is accompanied by endothelial dysfunction in mesenteric vessels with impaired PI3-kinase-dependent NO production and enhanced MAPK-dependent ET-1 secretion. These results may reflect pathophysiology in other vascular beds that directly contribute to elevated peripheral vascular resistance and hypertension.  相似文献   
64.
R-spondin1 (Rspo1) is a secreted protein that enhances Wnt signaling, which has crucial functions in embryonic development and several cancers. C-mannosylation is a rare type of glycosylation and might regulate secretion, protein–protein interactions, and enzymatic activity. Although human Rspo1 contains 2 predicted C-mannosylation sites, C-mannosylation of Rspo1 has not been reported, nor have its functional effects on this protein. In this study, we demonstrate by mass spectrometry that Rspo1 is C-mannosylated at W153 and W156. Using Lec15.2 cells, which lack dolichol-phosphate-mannose synthesis activity, and mutant Rspo1-expressing cells that replace W153 and W156 by alanine residues, we observed that C-mannosylation of Rspo1 is required for its secretion. Further, the enhancement of canonical Wnt signaling by Rspo1 is regulated by C-mannosylation. Recently DPY19 was reported to be a C-mannosyltransferase in Caenorhabditis elegans, but no C-mannosyltransferases have been identified in any other organism. In gain- and loss-of-function experiments, human DPY19L3 selectively modified Rspo1 at W156 but not W153 based on mass spectrometry. Moreover, knockdown of DPY19L3 inhibited the secretion of Rspo1. In conclusion, we identified DPY19L3 as the C-mannosyltransferase of Rspo1 at W156 and found that DPY19L3-mediated C-mannosylation of Rspo1 at W156 is required for its secretion.  相似文献   
65.
Optimists hold positive a priori beliefs about the future. In Bayesian statistical theory, a priori beliefs can be overcome by experience. However, optimistic beliefs can at times appear surprisingly resistant to evidence, suggesting that optimism might also influence how new information is selected and learned. Here, we use a novel Pavlovian conditioning task, embedded in a normative framework, to directly assess how trait optimism, as classically measured using self-report questionnaires, influences choices between visual targets, by learning about their association with reward progresses. We find that trait optimism relates to an a priori belief about the likelihood of rewards, but not losses, in our task. Critically, this positive belief behaves like a probabilistic prior, i.e. its influence reduces with increasing experience. Contrary to findings in the literature related to unrealistic optimism and self-beliefs, it does not appear to influence the iterative learning process directly.  相似文献   
66.
67.
A novel class of benzimidazole NPY Y5 receptor antagonists was prepared exploiting a privileged spirocarbamate moiety. The structure-activity relationship of this series and efforts to achieve a profile suitable for further development and an appropriate pharmacokinetic profile in rat are described. Optimisation led to the identification of the brain penetrant, orally bioavailable Y5 antagonist 9b which significantly inhibited the food intake induced by a Y5 selective agonist with a minimal effective dose of 30mg/kg po.  相似文献   
68.
Ovarian carcinomas are often highly invasive, especially in the peritoneal cavity; however, the mechanism involved in invasion is not yet fully understood. In the present research, we studied the role of NF-κB in the invasiveness of ovarian carcinoma cells by using (−)-DHMEQ, a specific inhibitor of NF-κB. (−)-DHMEQ inhibited invasion in vitro and the expression of CXCL12 and CXCR4. We found that neutralizing antibody against CXCR4 or knockdown of CXCR4 suppressed the invasion. Proteomic analysis revealed that CXCR4-siRNA treatment lowered the secretion of several invasion-related proteins, such as MMP-9 and uPA. These data imply that (−)-DHMEQ suppressed ovarian cell invasion via inhibition of the NF-κB-regulated autocrine system of CXCL12-CXCR4.  相似文献   
69.
Conophylline (CNP) has various biological activities, such as insulin production. A recent study identified ADP-ribosylation factor-like 6-interacting protein 1 (ARL6ip1) as a direct target protein of CNP. In this study, we revealed that ARL6ip1 is a three-spanning transmembrane protein and determined the CNP-binding domain of ARL6ip1 by deletion mutation analysis of ARL6ip1 with biotinyl-amino-CNP. These results suggest that CNP is expected to be useful for future investigation of ARL6ip1 function in cells. Because of the anti-apoptotic function of ARL6ip1, CNP may be an effective therapeutic drug and/or a novel chemosensitizer for human cancers and other diseases.  相似文献   
70.
Summary

Studies on the weeds of cultivated land in Italy. IV: Weeds of a small farm near Montecatini Terme.

In the first part of this researche, the author gives the chief climatic data of the Montecatini Terme zone together with pedological informations about the stations offered by a small farm on which biological and statistical investigations are conducted.

All weeds (241 species) found on the area of the small farm are listed. For each species is indicated Raunhiaer's biological form, its occurence in cultivated fields or in path lanes, graves and fences.

The most of them are Therophytes (55%) and Hemicriptophytes (30%). Scarcely represented are the Geophytes (8,33%), Chamaephytes (3,75%), Phanerophytes (2,92%). Therophytes increase very much (till 78%) if only are considered the species which occur in cultivated ground.

In the second part of the work is conducted a bio-statistical study on the weeds behaviour in eight fields. Once a month, on thiese fields, statistical relieves have been made after Raunkiaer's method. The results are condensed in graphics in which, besides the percent frequences of the various weeds, are also reported the various biological stages, the types of root-system and the influence of the tillages.

Follows an examination of the weeds which have been found in the various cultivations (wheat, patatoes, corn, legumes ecc). The most important weeds (36 species) are, then, biologically and phyto-geografically classified in accordance with Korsmo's and Eig's systems, respectively. Of these weeds 81% are «seed plants» and 19% are «wandering plant» 52,7% belong to «liason group», 36,1% are polychorous or adventicious, 11,2% belong to mediterranean Element. «Stationary plants» are missing, it depends upon the fact that there are only annual crops.

At last, for the most important weeds, details are given about germination, blossoming and dissemination time, their relations with crops, their occurrence in the low or in the high part of the farm.

For a resume, conclusions are as follow:

1°) The slope of the ground influences weed distribution on the fields of the farm; many of them (specially the winter-spring species) prefer cool fields of the low part of the farm, so that the high one is infested by a relatively small number of weeds;

2°) the greatest number of weeds is found in the fields in spring time;

3°) annual plants are prevailing over perennial ones;

4°) the most infested crop is weat, the least is potatoes;

5°) Variations of winter precipitations and, sometimes, of the sowing time may influence gravity of infestation by weeds.  相似文献   
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