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41.

Objective

To analyze trends in the use of partial nephrectomy, we evaluated which individual factors of renal nephrometry score (RNS) influenced the operative approach bi-annually from 2008 to 2014.

Materials and Methods

We performed a retrospective review of renal cell carcinoma treated by surgery in 2008, 2010, 2012, and 2014. The complexity of renal masses was measured using the R.E.N.A.L. nephrometry scoring system with CT or MRI. Group comparison in terms of operation year and surgical type (partial nephrectomy versus radical nephrectomy) was performed. We developed a nomogram to quantitate the likelihood of selecting partial nephrectomy over radical nephrectomy.

Results

A total of 1106 cases (237 in 2008, 225 in 2010, 292 in 2012, and 352 in 2014) were available for the study. Over the study period, the proportion of partial nephrectomies performed increased steadily from 21.5% in 2008 to 66.5% in 2014 (p < 0.05). Furthermore, use of partial nephrectomy increased steadily in all RNS complexity groups (low, moderate, and high) (p < 0.05). In the analysis of individual components of RNS, values of the R and N components increased statistically by year in the partial nephrectomy group (p < 0.05). Average AUC was 0.920.

Conclusions

The proportion of partial nephrectomies performed sharply increased over the study period. Additionally, over the study period, more partial nephrectomies were performed for renal masses of larger size and closer to the collecting system and main renal vessels. A nomogram developed based on this recent data set provides significant predictive value for surgical decision making.  相似文献   
42.
43.
Kim MK  Kim SD  Lee HY  Lee SY  Shim JW  Yun J  Kim JM  Min do S  Yoo YH  Bae YS 《FEBS letters》2008,582(23-24):3379-3384
The collagen-binding motif (CBM) peptide, a cleavage product of osteopontin (OPN), stimulated intracellular calcium increase in human neutrophils. CBM peptide-stimulated calcium was inhibited by pertussis toxin (PTX), suggesting the influence of PTX-sensitive G-proteins. In addition CBM peptide stimulated the chemotactic migration of human neutrophils and human monocytes. CBM peptide-induced neutrophil chemotaxis was completely inhibited by PTX, once again indicating the influence of Gi proteins. CBM peptide was also found to induce mitogen activated protein kinase activation. CBM peptide-induced neutrophil chemotaxis was mediated by p38 kinase as well as an extracellular signal-regulated protein kinase. Taken together, the results suggest that a cleavage product of OPN, CBM peptide, initiates immune responses by inducing neutrophil trafficking via certain PTX-sensitive cell surface receptors.  相似文献   
44.
Hybridization has long been considered a process that prevents divergence between species. In contrast to this historical view, an increasing number of empirical studies claim to show evidence for hybrid speciation without a ploidy change. However, the importance of hybridization as a route to speciation is poorly understood, and many claims have been made with insufficient evidence that hybridization played a role in the speciation process. We propose criteria to determine the strength of evidence for homoploid hybrid speciation. Based on an evaluation of the literature using this framework, we conclude that although hybridization appears to be common, evidence for an important role of hybridization in homoploid speciation is more circumscribed.  相似文献   
45.
Phosphotyrosyl phosphatase activator (PTPA) is decreased in the brains of Alzheimer's disease (AD) and the AD transgenic mouse models. Here, we investigated whether down‐regulation of PTPA affects cell viability and the underlying mechanisms. We found that PTPA was located in the integral membrane of mitochondria, and knockdown of PTPA induced cell apoptosis in HEK293 and N2a cell lines. PTPA knockdown decreased mitochondrial membrane potential and induced Bax translocation into the mitochondria with a simultaneous release of Cyt C, activation of caspase‐3, cleavage of poly (DNA ribose) polymerase (PARP), and decrease in Bcl‐xl and Bcl‐2 protein levels. Over‐expression of Protein phosphatase 2A (PP2A) catalytic subunit (PP2AC) did not rescue the apoptosis induced by PTPA knockdown, and PTPA knockdown did not affect the level of and their phosphorylation of mitogen‐activated protein kinases (MAPKs), indicating that PP2A and MAPKs were not involved in the apoptosis induced by PTPA knockdown. In the cells with over‐expression of tau, PTPA knockdown induced PP2A inhibition and tau hyperphosphorylation but did not cause significant cell death. These data suggest that PTPA deficit causes apoptotic cell death through mitochondrial pathway and simultaneous tau hyperphosphorylation attenuates the PTPA‐induced cell death.

  相似文献   

46.
Hyaluronic acid (HA) hydrogel beads were prepared by photopolymerization of methacrylated HA and N-vinylpyrrolidone using alginate as a temporal spherical mold. Various fabrication conditions for preparing the hydrogel beads, such as the concentration of methacrylated HA and UV irradiation time, were optimized to control swelling properties and enzymatic degradability. A new concept for cell encapsulation is proposed in this paper. Viable cells were directly injected into the hydrogel beads using a microinjection technique. When bovine articular chondrocytes were injected into HA hydrogel beads and cultivated for 1 week, the cells could proliferate well within the HA beads. HA hydrogel beads could be potentially used as injectable cell delivery vehicles for regenerating tissue defects.  相似文献   
47.
The species of Prosopis (Leguminosae) are welladapted to grow in the arid regions of the world. In Mexico, nearly 70%of its territory accounts for arid lands and nine species of this genus arefound in the country which are currently utilized for multiple purposes. Giventhat a sustainable exploitation of this important natural resource is necessary,knowledge of the genetic variability of natural populations is required. Thegenetic variation among and within four wild populations of Prosopisglandulosa, P. juliflora, and two ofP. laevigata, located in the Mexican States of Chihuahua(1), Sinaloa (2), Guanajuato (3) and Hidalgo (4), respectively, was determinedusing random amplified polymorphic DNA (RAPDs). There was a genetic variation of72.48% among these four populations, and within them the estimated geneticvariation was 27.52%. Between the populations of P.laevigata the genetic variation obtained was 7.15%, and within them92.85% (AMOVA, P < 0.001). Based on the assumption ofWright's island model, the genetic variation found among populations correspondsto a gene flow (Nem) of 0.09, while the gene flow detected betweenthe populations of P. laevigata was 3.2. A total of 27 RAPDphenotypes were identified in the four populations; among them, 11 correspondedto P. laevigata. The phylogenetic analyses showed that thethree species are differentiated in three clades and that probably P.juliflora was the origin of the other two species. The protogynoustrait of their flowers and the outcrossing are the main factors that may explainthe genetic variation observed in these populations.  相似文献   
48.
Gain in 1q is a common abnormality in phyllodes tumours of the breast.   总被引:4,自引:0,他引:4  
We studied DNA copy number changes by CGH and allelic imbalance (AI) on 3p by LOH analysis on 22 phyllodes tumours (PT) of the breast in order to gain insight into the genetic basis of tumour progression in PT. Copy number changes were observed in 14 cases (63%). Gain in 1q with 1q21-23 as the minimal overlapping area was seen in 12 cases (55%). The gain was observed both in benign and malignant tumours. Our study did not reveal any DNA copy number changes or allelic loss on 3p. The results suggest that DNA copy number changes are not associated with the histological grade or clinical behaviour of PT and the chromosomal changes on 3p appear to be rare. Colour figure can be viewed on http://www.esacp.org/acp/2003/25-2/jee.htm  相似文献   
49.
Pretreatment of corn stover by aqueous ammonia   总被引:20,自引:0,他引:20  
Corn stover was pretreated with aqueous ammonia in a flow-through column reactor, a process termed ammonia recycled percolation (ARP). This method was highly effective in delignifying of the biomass, reducing the lignin content by 70-85%. Most lignin removal occurred within the first 20 min of the process. Lignin removal by ARP was further confirmed by FTIR analysis and lignin staining. The ARP process solubilized 40-60% of the hemicellulose but left the cellulose intact. The solubilized carbohydrate existed in oligomeric form. Carbohydrate decomposition during the pretreatment was insignificant. Corn stover treated for 90 min exhibited enzymatic digestibility of 99% with 60 FPU/g of glucan enzyme loading, and 92.5% with 10 FPU/g of glucan. The digestibility of ARP treated corn stover was substantially higher than that of alpha-cellulose. The enzymatic digestibility was related with the removal of lignin and hemicellulose, perhaps due to increased surface area and porosity. The SEM pictures indicated that the biomass structure was deformed and its fibers exposed by the pretreatment. The crystallinity index increased with pretreatment reflecting removal of the amorphous portion of biomass. The crystalline structure of the cellulose in the biomass, however, was not changed by the ARP treatment.  相似文献   
50.
The artificial gene coding for anticoagulant hirudin was placed under the control of theGAL10 promoter and expressed in the galactokinase-deficient strain (Δgal1) ofSaccharomyces cereivisiae, which uses galactose only as a gratuitous inducer in order to avoid its consumption. For efficient production of recombinant hirudin, a carbon source other than galactose should be provided in the medium to support growth of the Δgal1 strain. Here we demonstrate the successful use of glucose in the fed-batch fermentation of the Δgal1 strain to achieve efficient production of recombinant hirudin, with a yield of up to 400 mg hirudin/L.  相似文献   
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