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31.
Significance of venous anastomosis in fingertip replantation   总被引:5,自引:0,他引:5  
Adequate venous outflow is the most important factor for successful fingertip replantation. The authors have attempted venous anastomosis in all cases of fingertip replantation to overcome postoperative congestion. In this article, the significance of venous repair for fingertip replantation is described from the authors' results of 64 complete fingertip amputations in 55 consecutive patients, which were replanted from January of 1996 to June of 2001. The overall survival rate was 86 percent. Of the 44 replantations in zone I, 37 survived, and the success rate was 84 percent. Of the 20 replantations in zone II, 18 survived, and the success rate was 90 percent. Venous anastomosis was attempted in all cases, but it was possible in 39 zone I and in all zone II replantations. For arterial repair, vein grafts were necessary in 17 of the 44 zone I and in one of the 20 zone II replantations; for venous repair, they were necessary in six zone I replantations and one zone II replantation. Postoperative vascular complications occurred in 15 replantations. There were five cases of arterial thrombosis and 10 cases of venous congestion. Venous congestion occurred in nine zone I and one zone II replantations. In five of these 10 replantations, venous anastomosis was not possible. In another five replantations, venous outflow was established at the time of surgery, but occlusion occurred subsequently. Except for the five failures resulting from arterial thrombosis, successful venous repair was possible in 49 of 59 replantations (83 percent). Despite the demand for skillful microsurgical technique and longer operation time, the authors' results using venous anastomosis in successful fingertip replantations are encouraging. By performing venous anastomosis, external bleeding can be avoided and a higher survival rate can be achieved. Venous anastomosis for fingertip replantation is a reliable and worthwhile procedure.  相似文献   
32.
Vertebrate Hedgehog signals are transduced through the primary cilium, a specialized lipid microdomain that is required for Smoothened activation. Cilia-associated sterol and oxysterol lipids bind to Smoothened to activate the Hedgehog pathway, but how ciliary lipids are regulated is incompletely understood. Here we identified DHCR7, an enzyme that produces cholesterol, activates the Hedgehog pathway, and localizes near the ciliary base. We found that Hedgehog stimulation negatively regulates DHCR7 activity and removes DHCR7 from the ciliary microenvironment, suggesting that DHCR7 primes cilia for Hedgehog pathway activation. In contrast, we found that Hedgehog stimulation positively regulates the oxysterol synthase CYP7A1, which accumulates near the ciliary base and produces oxysterols that promote Hedgehog signaling in response to pathway activation. Our results reveal that enzymes involved in lipid biosynthesis in the ciliary microenvironment promote Hedgehog signaling, shedding light on how ciliary lipids are established and regulated to transduce Hedgehog signals.  相似文献   
33.
The aim of current work was to determine essential oils (EOs) composition from three Eucalyptus species, including E. citriodora, E. camaldulensis and E. globulus and assess their α-glucosidase inhibitory activity. The EOs were collected using the hydrodistillation technique and characterized by GC/MS, GC-FID and NMR. The isolated EOs from leaves parts of Eucalyptus species varied from 0.56 to 1.0 % on fresh weight basis. The content of the EOs was distinct according to the species. The most abundant metabolites were identified as citronellal (0–83.0 %), 1,8-cineole (0.2–44.8 %), spathulenol (0.4–16.1 %) α-pinene (0.4–15.9 %), p-cymene (3.7–11.9 %), citronellol (0–8.6 %), β-eudesmol (5.3–8.6 %) and β-pinene (0–7.1 %). The EOs obtained from targeted samples exhibited strong α-glucosidase inhibitory activity. These results are encouraging and underline that the EOs of Eucalyptus species may be a promising alternative source of natural antidiabetic.  相似文献   
34.
In vitro responses of embryogenic sugarcane (Saccharum officinarum L.; cv. CoC-671) calli stressed with different levels of NaCl (0.0, 42.8, 85.6, 128.3, 171.1, 213.9 or 256.7 mM) were studied. The results showed that a significant decrease in callus growth and cell viability occurred with ≥85.6 mM NaCl. Higher amounts of free proline and glycine betaine were accumulated in NaCl-stressed calli. Although the leached and retained Na+ contents increased, the retained K+ content decreased with increasing levels of NaCl. Such a mechanism implies that sugarcane can be considered as a Na+-excluder. The accumulation of salt ions and osmolytes could play an important role in osmotic adjustment in sugarcane cells under salt stress.  相似文献   
35.
Crude venom from two elapid snakes Pseudechis australis and Pseudechis butleri was fractionated by gel filtration chromatography and selected fractions screened for in vitro insulin-releasing activity using clonal pancreatic BRIN-BD11 cells. Following acute 20-min incubation at 5.6 mM glucose, 9 fractions exhibited significant (P < 0.001) insulin-releasing activity. Structural characterisation of active fractions was achieved primarily using MALDI–TOF MS and N-terminal Edman degradation sequencing. The partial N-terminal sequences are reported for a total of 7 venom components. Their homology to existing sequences as determined using BLAST searching uncovered the main insulin-releasing families as being phospholipases A2 and short α-neurotoxins. A number of sequences are reported for the first time from P. butleri venom which is much less studied than the related P. australis.  相似文献   
36.
Flor yeasts grow and survive in fino sherry wine where the frequency of respiratory-deficient (petite) mutants is very low. Mitochondria from flor yeasts are highly acetaldehyde- and ethanol-tolerant, and resistant to oxidative stress. However, restriction fragment length polymorphism (RFLP) of mtDNA from flor yeast populations is very high and reflects variability induced by the high concentrations of acetaldehyde and ethanol of sherry wine on mtDNA. mtDNA RFLP increases as the concentration of these compounds also increases, but is followed by a total loss of mtDNA in petite cells. Yeasts with functional mitochondria (grande) are target of continuous variability, so that flor yeast mtDNA can evolve extremely rapidly and may serve as a reservoir of genetic diversity, whereas petite mutants are eventually eliminated because metabolism in sherry wine is oxidative.  相似文献   
37.
The influence of Zn2+ (6.0 × 10–3 –18.0 × 10–3 M) and Cu2+ (4 × 10–4 –1.2 × 10–4 M) in the basal medium on mycelial growth (dry weight), activities of lignin peroxidase (Lip), manganese peroxidase (Mnp), solubilization, and mineralization (14CO2 evolution) of lignin during a period of 3 weeks was studied in Phanerochaete chrysosporium strain MTCC-787. Highest mycelial growth was obtained at 0.6 M Zn2+ and 0.4 M Cu2+ levels. Enzyme activities were found to increase up to the highest levels of both the trace elements. However, Zn2+ had a relatively more stimulatory effect on Lip production and the reverse was true in case of Cu2+. [14C]Lignin solubilization was also promoted by higher levels of both trace elements. Mineralization of [14C]lignin was optimal at 6.0 M Zn2+ and 1.2 M Cu2+. The stimulatory effect of Zn2+ on Lip production was correlated with higher rates of [14C]lignin mineralization.  相似文献   
38.
39.
Calcium ion (Ca2+) is a ubiquitous second messenger that transmits various internal and external signals including stresses and, therefore, is important for plants’ response process. Calcineurin B-like proteins (CBLs) are one of the plant calcium sensors, which sense and convey the changes in cytosolic Ca2+-concentration for response process. A search in four leguminous plant (soybean, Medicago truncatula, common bean and chickpea) genomes identified 9 to 15 genes in each species that encode CBL proteins. Sequence analyses of CBL peptides and coding sequences (CDS) suggested that there are nine original CBL genes in these legumes and some of them were multiplied during whole genome or local gene duplication. Coding sequences of chickpea CBL genes (CaCBL) were cloned from their cDNAs and sequenced, and their annotations in the genome assemblies were corrected accordingly. Analyses of protein sequences and gene structures of CBL family in plant kingdom indicated its diverse origin but showed a remarkable conservation in overall protein structure with appearance of complex gene structure in the course of evolution. Expression of CaCBL genes in different tissues and in response to different stress and hormone treatment were studied. Most of the CaCBL genes exhibited high expression in flowers. Expression profile of CaCBL genes in response to different abiotic stresses and hormones related to development and stresses (ABA, auxin, cytokinin, SA and JA) at different time intervals suggests their diverse roles in development and plant defence in addition to abiotic stress tolerance. These data not only contribute to a better understanding of the complex regulation of chickpea CBL gene family, but also provide valuable information for further research in chickpea functional genomics.  相似文献   
40.
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