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81.
Neurological Sciences - Autoimmune encephalitis (AE) is caused by the antibodies that target receptors and intracellular or surface proteins. To achieve the appropriate therapeutic results, early...  相似文献   
82.
Source Apportionment of Volatile Organic Compounds in Tehran, Iran   总被引:3,自引:0,他引:3  
Identifying the sources of volatile organic compounds (VOCs) is key issue to reducing ground-level ozone and PAN. A multivariate receptor model (Unmix) was used for the determination of the contributions of VOCs sources in Tehran-Iran. Concentrations of ambient C2–C10 VOCs were measured continuously and online at the center of Tehran city during the winter of 2012. A high correlation coefficient existed between measured and predicted values (R 2 = 0.99), indicating that the data were well modeled. Five possible VOCs source categories were identified and mobile sources such as vehicle exhaust (61 %) and fuel evaporation (12 %) more than half of the total VOC concentration. City gas and CNG sources, biogenic source, and industrial solvent source categories accounted for 17 %, 8 % and 2 % of the total VOC, respectively. Result showed Unmix for VOCs source apportionment can be used to analyze and generate air pollution control strategies and policies.  相似文献   
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After treatment with continuous positive airway pressure (CPAP) via nasal masks and a face mask, three neonates developed pressure necrosis involving their central forehead and left eyebrow. The pressure necrosis resulted in permanent scarring in all three infants. We describe a case series of a new cutaneous iatrogenic complication of CPAP.  相似文献   
86.
In this study, we evaluated the effect of dexamethasone used as a prophylaxis for nausea and vomiting on the incidence of postdural puncture headache (PDPH) in pregnant women receiving spinal anesthesia for cesarean section. In a prospective, randomized, double-blind, placebo-controlled study, 372 women under spinal anesthesia received 8?mg of dexamethasone or placebo intravenously just after the umbilical cord was clamped. The rate of PDPH and correlated risk factors were evaluated. The prevalence of nausea and vomiting in the dexamethasone and placebo groups was 54.4 and 51.7?%, respectively. There was no statistically meaningful difference between the results (P value?=?0.673). The overall incidence rate of PDPH was 10.8?%, with 28 cases from the dexamethasone group compared with 11 subjects from the placebo group (P value?=?0.006). This effect was most prominent on the first day (P value?=?0.046) and disappeared on the second day after spinal anesthesia (P value?=?0.678). Prophylactic treatment with 8?mg of dexamethasone not only increases the severity and incidence of PDPH, but is also ineffective in decreasing the prevalence of intra-operative nausea and vomiting during cesarean section. The treatment is a significant risk factor for the development of PDPH.  相似文献   
87.

Aim

Based on previous investigations, the progress of gastritis may lead to gastric carcinomas. In some epithelial tumors, macrophage migration inhibitory factor (MIF), which is an inflammatory cytokine may inactivate p53 and play a role in tumorigenesis process. We decided to evaluate clinicopathological significance of MIF expression and the relation between p53 and MIF expressions in gastric adenocarcinomas.

Methods

Seventy-three consecutive cases of gastric adenocarcinomas, the tissue samples of which were available, were included in this study. Tissue sections were stained for MIF and p53 expression by immunohistochemistry and the expression was defined as positive (for more than 10%) and negative (for less than 10%) groups. Location of the tumor, histological subtypes, and grade of the tumor were determined by using routine H&;E staining. Distant metastasis, lymph node involvement, and consequently the stage of tumor were specified. The patients?? age and gender were obtained from their medical records. The relationship between expression of MIF and these variables was determined.

Results

Overexpression of MIF was observed in the cytoplasm of cancer cells in 46.6% (34/73) of cases and nuclear immunostaining of p53 was observed in 37% (27/73) of cases. Expression of MIF was significantly correlated with the location of tumor, but this expression has no statistically significant correlation with variables including: age, gender histological subtypes, distant metastasis, and lymph node involvement, stage and grade of the tumor, and p53 tumor suppressor gene expression.

Conclusions

Our study suggests that MIF in gastric adenocarcinomas versus many other epithelial tumors cannot have a prominent role in tumor progress and inactivation of p53 tumor suppressor gene.  相似文献   
88.
Cell migration and spreading involve the coordination of membrane trafficking, actomyosin contraction, and modifications to plasma membrane tension and area. The biochemical or biophysical basis for this coordination is however unknown. In this study, we show that during cell spreading, lamellipodia protrusion flattens plasma membrane folds and blebs and, once the plasma membrane area is depleted, there is a temporary increase in membrane tension by over twofold that is followed by activation of exocytosis and myosin contraction. Further, an artificial increase in plasma membrane tension stopped lamellipodia protrusion and activated an exocytotic burst. Subsequent decrease in tension restored spreading with activation of contraction. Conversely, blebbistatin inhibition of actomyosin contraction resulted in an even greater increase in plasma membrane tension and exocytosis activation. This spatiotemporal synchronization indicates that membrane tension is the signal that coordinates membrane trafficking, actomyosin contraction, and plasma membrane area change. We suggest that cells use plasma membrane tension as a global physical parameter to control cell motility.  相似文献   
89.

Background

The importance of resting heart rate as a prognostic factor was described in several studies. An elevated heart rate is an independent risk factor for adverse cardiovascular events and total mortality in patients with coronary artery disease, chronic heart failure, and the general population. Also heart rate is elevated in the Multi Organ Dysfunction Syndrome (MODS) and the mortality due to MODS is highly correlated with inadequate sinus tachycardia.To evaluate the value of resting heart rate in predicting mortality in patients with traumatic brain injury along scoring systems like Acute Physiology and Chronic Health Evaluation(APACHE II), Sequential Organ Failure Assessment (SOFA) and Glasgow Coma Score (GCS).

Method

By analyzing data which was collected from an open labeled randomized clinical trial that compared the different means of osmotherapy (mannitol vs bolus or infusion hypertonic saline), heart rate, GCS, APACHE II and SOFA score were measured at baseline and daily for 7 days up to 60 days and the relationship between elevated heart rate and mortality during the first 7 days and 60th day were assessed.

Results

After adjustments for confounding factors, although there was no difference in mean heart rate between either groups of alive and expired patients, however, we have found a relative correlation between 60th day mortality rate and resting heart rate (P=0.07).

Conclusion

Heart rate can be a prognostic factor for estimating mortality rate in brain injury patients along with APACHE II and SOFA scores in patients with brain injury.  相似文献   
90.
1. NK1 and NK2 tachykinin receptors were characterized in guinea-pig and rat bronchopulmonary systems and in the vasculature of the rat by use of radioligand binding and/or functional studies. 2. The radioligands for NK1 and NK2 receptors ([3H]-SP and [3H]-pNKA, respectively) did not label tachykinin receptors in homogenates of rat lungs or bronchi. In contrast, in the guinea-pig, [3H]-SP bound with high affinity to these tissues (KD = 0.23 +/- 0.08 nM and 0.34 +/- 0.05 nM, for lungs and bronchi, respectively). The total number of binding sites was 4.6 fold greater in bronchus (Bmax = 135 +/- 27 fmol mg-1 protein) than in lung homogenates (Bmax = 29.3 +/- 0.1 fmol mg-1 protein). Furthermore, this binding was markedly displaced by CP-96,345 (pKi = 9.5 +/- 0.1) and RP 67580 (pKi = 7.6 +/- 0.1), antagonists of NK1 receptors, slightly displaced by SR 48968 (pKi = 6.6 +/- 0.1), but not affected by actinomycin D or L-659,877, antagonists of NK2 receptors. Specific binding of [3H]-pNKA, detected in guinea-pig bronchi (KD = 5.2 +/- 0.1 nM, and Bmax = 203 +/- 19 fmol mg-1 protein) but not in lungs, was similarly (40 to 53%) displaced by RP 67580 (1 microM), CP-96,345 (10 and 100 nM) or SR 48968 (10 and 100 nM). The displacement approximately doubled (87 to 91%) when SR 48968 (10 nM) was combined with either RP 67580 (1 microM) or CP-96,345 (10 nM), but not when RP 67580 was combined with CP-96,345. 3. In urethane-anaesthetized guinea-pigs, i.v. injections of the NK1 receptor agonists SP, [Pro9]-SP, [Sar9,Met(O2)11]-SP and septide, as well as the NK2 receptor agonists NKA and [Lys5,MeLeu9,NLeu10]-NKA(4-10) (0.1-10 micrograms kg-1, i.v.), dose-dependently increased lung inflation pressure. The most potent of these peptides were septide and [Lys5, MeLeu9,NLeu10]-NKA(4-10) (EC50 = 0.38 +/- 0.07 and 0.07 +/- 0.02 microgram kg-1, respectively). Interestingly, septide was 130 fold less potent than SP in displacing [3H]-SP from its binding sites in the guinea-pig lung, whereas it was 14 fold more potent than SP as a bronchoconstrictor. RP 67580 (0.3-5 mg kg-1, i.v.) and CP-96,345 (0.01-3 mg kg-1, i.v.) dose-dependently reduced the bronchoconstriction produced by the NK1 receptor agonists.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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