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101.
102.
Liquid microchannels on structured surfaces are built up using a wettability pattern consisting of hydrophilic stripes on a hydrophobic substrate. These channels undergo a shape instability at a certain amount of adsorbed volume, from a homogeneous state with a spatially constant cross section to a state with a single bulge. This instability is quite different from the classical Rayleigh Plateau instability and represents a bifurcation between two different morphologies of constant mean curvature. The bulge state can be used to construct channel networks that could be used as fluid microchips or microreactors. 相似文献
103.
Evaluation of small-intestinal submucosa implants for repair of meniscal defects in dogs 总被引:9,自引:0,他引:9
Welch JA Montgomery RD Lenz SD Plouhar P Shelton WR 《American journal of veterinary research》2002,63(3):427-431
OBJECTIVE: To assess the effects of porcine small intestinal submucosa (SIS) implants on the healing of meniscal lesions in dogs. ANIMALS: 16 adult Greyhounds of both sexes. PROCEDURE: Unilateral osteotomy was performed at time 0 to disrupt the medial collateral ligament attachment, and two (1 cranial and 1 caudal) 4-mm circular defects were created in the avascular portion of the medial meniscus. One defect was filled with an SIS graft, and the other defect remained empty (control). Three months later, the identical procedure was performed on the contralateral limb. Three months after the second surgery, dogs were euthanatized, and meniscal tissue specimens from both stifle joints were collected for gross, histologic, biomechanical, and biochemical evaluations. RESULTS: Regenerative tissue was evident in 4 (2 SIS-implanted and 2 control) of 16 defects examined histologically. In 3 defects, this thin bridge of tissue was composed of immature haphazardly arranged fibrous connective tissue with a relatively uniform distribution of fibroblasts. Aggregate modulus, Poisson ratio, permeability, and shear modulus were not significantly different between control and SIS-implanted defects either 3 or 6 months after surgery. Hydroxyproline content also did not differ between SIS-implanted and control defects at 3 or 6 months. CONCLUSIONS AND CLINICAL RELEVANCE: Implantation of porcine SIS into experimentally induced meniscal lesions in dogs did not promote tissue regeneration. 相似文献
104.
Lindsay DS Dykstra CC Williams A Spencer JA Lenz SD Palma K Dubey JP Blagburn BL 《Veterinary parasitology》2000,92(2):157-163
Equine protozoal myeloencephalitis (EPM) is a neurologic syndrome in horses from the Americas and is usually caused by infection with the apicomplexan parasite, Sarcocystis neurona. A horse model of EPM is needed to test the efficacy of chemotherapeutic agents and potential vaccines. Five horses that were negative for antibodies to S. neurona in their serum and cerebrospinal fluid (CSF) were injected in the subarachnoid space with living merozoites of the SN2 isolate of S. neurona. None of the horses developed clinical disease or died over a 132-day observation period. All five horses developed antibodies to S. neurona in their CSF and serum 3-4 weeks after injection. Two of the horses were examined at necropsy and no parasite induced lesions were observed in their tissues and no parasites were recovered from portions of their spinal cords inoculated on to cell cultures. Results of this study demonstrate that merozoites of the SN2 isolate of S. neurona will induce seroconversion but not clinical disease when inoculated directly into the CSF of nonimmune horses. 相似文献
105.
106.
EOS Batista GG Macedo RV Sala MDDV Ortolan MF Sá Filho TA Del Valle EF Jesus RNVR Lopes FP Rennó PS Baruselli 《Reproduction in domestic animals》2014,49(3):448-452
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers. 相似文献
107.
F. Lenz 《植物养料与土壤学杂志》1977,140(1):51-61
Fruit Effect on Photosynthesis and Respiration Several investigations about fruit effects on photosynthesis and respiration, mainly of Citrus madurensis (Lour.) and Solanum melongena (L) plants are reviewed. Fruiting plants had higher photosynthetic rates (mg CO2 · dm?2 · h?1) than non fruiting ones, particularly during stages of most intensive fruit growth. The photosynthetic rates could be stimulated by increasing fruit temperatures. No differences in dark respiration rates of fruiting and non fruiting plants were observed. However photorespiration was considerably higher in non fruiting plants as compared to fruiting ones. Leaves of non fruiting plants accumulated more sugars and starch in the leaves during the light periods than fruiting ones. The gaseous diffusive resistance of leaves was higher in non fruiting as compared to fruiting ones. The higher photosynthetic efficiency of fruiting plants is probably controlled by several mechanisms, some of which were discussed in the paper. 相似文献
108.
109.
The specific rate of CO(2) efflux (respiration) from roots of intact fruiting calamodin plants (Citrus madurensis Lour.) showed no diel trend, and did not respond significantly to short-term (2 day) changes in shoot irradiance. Mean root respiration rate was about 8.4 nmol CO(2) g(-1) s(-1) at 20 degrees C, and increased with temperature with a Q(10) of about 2. In calamodin plants, the proportion of total root length that was white averaged 6.0 mm m(-1). Respiration of roots of apple plants (Malus domestica Borkh.), planted in spring as rootstocks and grown at high irradiance and N supply, declined from about 5.3 to 2.8 nmol CO(2) g(-1) s(-1) between 46 and 138 days after bud burst. At 50% irradiance, root respiration was reduced more than 25% at 46 and 92 days after bud burst, but was not significantly affected later in the season. Reducing shoot irradiance reduced the proportion of total root length that was white, e.g., from 217 to 146 mm m(-1) at 46 days after bud burst. For plants previously grown at low irradiance, increasing shoot irradiance for 6 days increased the rate of root respiration by 5 to 10%. For plants previously grown at high irradiance, reducing shoot irradiance for 6 days reduced root respiration by about 20% early in the season, but had no significant effect later in the season. For plants grown with low-N supply (5% of the high-N), root respiration was reduced early in the season, but was not significantly affected later. Reducing the N supply increased slightly the proportion of total root length that was white. For plants previously grown with low-N, increasing the N supply for 6 days reduced further the rate of root respiration. For plants previously grown with high-N, reducing the N supply for 6 days did not significantly affect the rate of root respiration. Specific respiration rates of root systems excised from mature trees growing outdoors peaked in June, at about 2.4 nmol CO(2) g(-1) s(-1), and then declined for the remainder of the growing season. 相似文献
110.