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1.
Due primarily to the increasing shortage of allogeneic donor organs, xenotransplantation has become the focus of a growing field of research. Currently, micropigs are the most suitable donor animal for humans. However, no standard method has been developed to evaluate the systemic vascular anatomy of micropigs and standard reference values to aid in the selection of normal healthy animals as potential organ donors are lacking. Using 64-channel multidetector row computed tomographic angiography (MDCTA), we evaluated morphological features of the major systemic vessels in micropigs and compared our results to published human data. The main vasculature of the animals was similar to that of humans, except for the iliac arterial system. However, diameters of the major systemic vessels were significantly different between micropigs and humans. Specifically, the diameter of the aortic arch, abdominal aorta, external iliac artery, and femoral artery, were measured as 1.50 ± 0.07 cm, 0.85 ± 0.06 cm, 0.52 ± 0.05 cm, and 0.48 ± 0.05 cm, respectively, in the micropigs. This MDCTA data for micropig major systemic vessels can be used as standard reference values for xenotransplantation studies. The use of 64-channel MDCTA enables accurate evaluation of the major systemic vasculature in micropigs.  相似文献   

2.
Pigs are the most likely source animals for cardiac xenotransplantation. However, an appropriate method for estimating the cardiac function of micropigs had not been established. Computed tomography (CT) analysis aimed at estimating cardiac function and assessing the coronary arteries has not been carried out in micropigs. This study determined the feasibility of evaluating cardiac function in a micropig model using multidetector row computed tomography (MDCT) and compared the cardiac function values with those of conventional pigs. The mean age of the conventional pigs and micropigs was approximately 80 days and approximately 360 days, respectively. The mean body weight in the conventional pigs and micropigs was 29.70 ± 0.73 and 34.10 ± 0.98 kg, respectively. Cardiac MDCT detected ejection fractions of 52.93 ± 3.10% and 59.00 ± 5.56% and cardiac outputs of 1.46 ± 0.64 l/min and 1.21 ± 0.24 l/min in conventional pigs and micropigs, respectively. There were no significant differences in cardiac function between conventional pigs and micropigs in the reconstructed CT images. There were also no differences in the coronary angiographic images obtained by MDCT. It is expected that the results of this study will help improve understanding of cardiac function in micropigs. The data presented in this study suggest that MDCT is a feasible method for evaluating cardiac function in micropigs.  相似文献   

3.
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors.  相似文献   

4.
Multidetector row computed tomography (MDCT) provides anatomical information about the kidney and other internal organs. Presently, the suitability of 64-channel MDCT to assess the kidney of healthy micropigs was evaluated. Morphological evaluations of the kidney and the major renal vessels of six healthy micropigs were carried out using MDCT, recording kidney volume and the diameter and length of renal arteries and veins. The mean diameters and lengths of the renal artery were 0.44 ± 0.05 and 4.51 ± 0.55 cm on the right side and 0.46 ± 0.06 and 3.36 ± 0.27 cm on the left side, respectively. The mean diameters and lengths of the renal vein were 1.44 ± 0.52 and 4.22 ± 1.29 cm on the right side and 1.38 ± 0.17 and 5.15 ± 0.87 cm on the left side, respectively. The mean volume of the right kidney was 79.3 ± 14.5 mL and of the left kidney was 78.0 ± 13.9 mL. The data presented in this study suggest that the MDCT offers a noninvasive, rapid, and accurate method for the evaluation of the renal anatomy in living kidney donors. It also provides sufficient information about extra-renal anatomy important for donor surgery and determination of organ suitability.  相似文献   

5.
Contrast-enhanced ultrasound is one of method for evaluating renal perfusion. The purpose of this project was to assess perfusion patterns and dynamics in normal micropig kidney using ultrasonographic contrast media. Eight young healthy micropigs were included in this study. Micropigs were anesthetized with propofol and received an intravenous bolus of microbubble contrast media through an ear vein. Time/mean pixel value (MPV) curves were generated for selected regions in the right renal cortex and medulla. The parenchyma was enhanced in two phases. The cortex was first enhanced followed by a more gradual enhancement of the medulla. A significant difference in perfusion was detected between the cortex and medulla. Following the bolus injection, the average upslope was 0.68 ± 0.27 MPV/sec, downslope was -0.27 ± 0.13 MPV/sec, baseline was 73.9 ± 16.5 MPV, peak was 84.6 ± 17.2 MPV, and time-to-peak (from injection) was 17.5 ± 6.6 sec for the cortex. For the medulla, the average upslope was 0.50 ± 0.24 MPV/sec, downslope was -0.12 ± 0.06 MPV/sec, baseline was 52.7 ± 7.0 MPV, peak was 65.2 ± 9.3 MPV, and time-to-peak (from injection) was 27.5 ± 5.0 sec. These data can be used as normal reference values for studying young micropigs.  相似文献   

6.
Serum bile acids as an indicator of liver disease in dogs   总被引:1,自引:0,他引:1  
Total serum bile acids were determined in 62 dogs with different primary or secondary liver diseases, using 3α-hydroxysteroid dehydrogenase coupled to nitrobluetetrazolium in a centrifugal analyzer. A reaction time of 4 min was sufficient, yielding a within run coefficient of variation of 7% at 6 µmol/1 and 3% at 27 µmol/1. A reference range of 0–4.4 µmol/1 2 h post prandially was observed. The sensitivity of bile acids as a liver function test was superior to that of alanine and aspartate aminotransferase, alkaline phosphatase, γ-glutamyltransferase and combinations of two of these. The bile acids test detected 36 of 39 patients with a morphological or clinical liver diagnosis. For dogs with heart failure the bile acids test was a markedly more sensitive indicator of secondary liver involvement than alanine aminotransferase or alkaline phosphatase. For secondary liver affections associated with pyometra or epilepsy medication the opposite was the case. Bile acid values in the pooled patient material was not correlated to any of the 4 enzymes measured. For cirrhosis there was positive correlation, however, with the amino transferase values.  相似文献   

7.

Background

Genetic and environmental factors, including dietary copper intake, contribute to the pathogenesis of copper‐associated hepatitis in Labrador retrievers. Clinical disease is preceded by a subclinical phase in which copper accumulates in the liver.

Objective

To investigate the effect of a low‐copper, high‐zinc diet on hepatic copper concentration in Labrador retrievers with increased hepatic copper concentrations.

Animals

Twenty‐eight clinically healthy, client‐owned Labrador retrievers with a mean hepatic copper concentration of 919 ± 477 mg/kg dry weight liver (dwl) that were related to dogs previously diagnosed with clinical copper‐associated hepatitis.

Methods

Clinical trial in which dogs were fed a diet containing 1.3 ± 0.3 mg copper/Mcal and 64.3 ± 5.9 mg zinc/Mcal. Hepatic copper concentrations were determined in liver biopsy samples approximately every 6 months. Logistic regression was performed to investigate effects of sex, age, initial hepatic copper concentration and pedigree on the ability to normalize hepatic copper concentrations.

Results

In responders (15/28 dogs), hepatic copper concentrations decreased from a mean of 710 ± 216 mg/kg dwl copper to 343 ± 70 mg/kg dwl hepatic copper after a median of 7.1 months (range, 5.5–21.4 months). Dogs from a severely affected pedigree were at increased risk for inability to have their hepatic copper concentrations normalized with dietary treatment.

Conclusions and Clinical Importance

Feeding a low‐copper, high‐zinc diet resulted in a decrease in hepatic copper concentrations in a subset of clinically normal Labrador retrievers with previous hepatic copper accumulation. A positive response to diet may be influenced by genetic background. Determination of clinical benefit requires further study.  相似文献   

8.
The concentrations of copper, zinc and molybdenum were measured in the liver of goats from western and south-eastern Norway. The mean copper concentrations in the liver of goats from these two districts were 23±19 µg Cu/g and 59±31 µg Cu/g wet weight, respectively. As for zinc and molybdenum, no difference was found between the two groups of animals. No correlations were detected between copper and zinc, zinc and molybdenum, or copper and molybdenum. The copper levels in Norwegian goat liver are considerably lower than in sheep liver, and the ranges are significantly more narrow. The concentrations of molybdenum in goat liver are at the same levels as in sheep and swine, while the levels of zinc are somewhat lower.  相似文献   

9.
The incidence and severity of fat infiltration in the liver of Finnish Ayrshire cows at 1 and 8 weeks after calving were studied. All multiparous (n = 88) and some primiparous (n = 17) cows that calved in 20 commercial milk recorded herds were investigated. The cows lost weight and a condition score decreased significantly (p < 0.05) during early lactation. Blood samples were taken at 1, 4 and 8 weeks after calving. Ketone body concentrations were highest at 4 weeks after calving. Albumin and total protein concentrations and ornithine carbamyltransferase activity in the blood increased significantly (p = < 0.05) from 1 to 8 weeks after calving. The percentage of liver fat (v/v) was significantly (p < 0.05) greater at 1 (3.9 ± 0.5 %) than at 8 weeks (1.2 ± 0.3 %) after calving. Eighty-nine of 102 cows had less than or equal to 9 % of fat in the liver (mean 2.3 ± 0.2 %), and 13 cows had more than 9% (mean 14.9 ± 1.2%) at 1 week after calving. Only blood acetoacetate and plasma aspartate aminotransferase differed significantly between the groups. In the fatty liver group the incidence rate of treated cases of ketosis was 30.8 ± 13.3 % and of parturient paresis 23.1 ± 12.2 %. In the non-fatty liver group the rates were 10.1 ± 3.2 % and 7.8 ± 2.9 %, respectively. The differences were not significant.  相似文献   

10.
The objective of this work was to study the effect of mild fat infiltration in the liver on the reproductive performance of Finnish Ayrshire cows. Eighty-five multiparous and 17 primiparous cows were investigated. The mean percentage of fat in the liver at 1 week after parturition was 3.9 ± 0.5. Cows with ≤ 9 % fat in the liver at 1 week after calving conceived slightly earlier than those with > 9% (87.1 ± 2.7 and 102.2 ± 15.0 days post partum, respectively). The difference was not statistically significant. The incidence rate of retentio secundina-rum and/or endometritis was significantly higher in the > 9 % fat group than in the ≤ 9 % fat group. Unobserved oestrus and ovarian cysts occurred with equal frequency in both groups.  相似文献   

11.
The objective of the present study was to examine the feasibility of the production of autologous porcine somatic cell nuclear transfer (SCNT) blastocysts using oocytes and donor cells from slaughtered ovaries. Therefore, we attempted to optimize autologous SCNT by examining the effects of electrical fusion conditions and donor cell type on cell fusion and the development of SCNT embryos. Four types of donor cells were used: 1) denuded cumulus cells (DCCs) collected from in vitro-matured (IVM) oocytes; 2) cumulus cells collected from oocytes after 22 h of IVM and cultured for 18 h (CCCs); 3) follicular cells obtained from follicular contents and cultured for 40 h (CFCs); and 4) adult skin fibroblasts. The DCCs showed a significantly (p < 0.01) lower rate of fusion than the CCCs when two pulses of 170 V/mm DC were applied for 50 µsec (19 ± 2% vs. 77 ± 3%). The rate of DCC fusion with oocytes was increased by the application of two DC pulses of 190 V/mm for 30 µsec, although this was still lower than the rate of fusion in the CCCs (33 ± 1% vs. 80 ± 2%). The rates of cleavage (57 ± 5%) and blastocyst formation (1 ± 1%) in the DCC-derived embryos did not differ from those (55 ± 6% and 3 ± 1%, respectively) in the CCC-derived SCNT embryos. Autologous SCNT embryos derived from CFCs (5 ± 2%) showed higher levels of blastocyst formation (p < 0.01) than CCC-derived autologous SCNT embryos (1 ± 0%). In conclusion, the results of the present study show that culturing cumulus and follicular cells before SCNT enhances cell fusion with oocytes and that CFCs are superior to CCCs in the production of higher numbers of autologous SCNT blastocysts.  相似文献   

12.
采用《GB 5413.38—2016 食品安全国家标准 生乳冰点的测定》测定生乳的冰点时,对冰点仪校准液的制备实施质量控制,使用该方法配制的冰点校准液(标准溶液A和标准溶液B)精密度和稳定性符合标准要求。试验结果表明,采用高纯度(99.90%)氯化钠配制的校准液精密度小于±1.0 m℃;在(5±1)℃的冷藏条件下保存73 天,冰点校准液测定值与理论值的偏差均小于±2.0 m℃,满足实验室的校准分析需求。  相似文献   

13.
Tracheal ultrasonography was performed to measure the width of the tracheal ring shadow and to assess the clinical relevance of these measurements for identifying tracheal collapse. The first tracheal ring width (FTRW) and thoracic inlet tracheal ring width (TITRW) were measured on both expiration and inspiration. The mean of the FTRW width (129 dogs) was greater in expiration (10.97 ± 1.02 mm, p = 0.001) than that in inspiration (9.86 ± 1.03 mm). For 51 normal dogs, the mean of the TITRW width was greater in expiration (9.05 ± 1.52 mm, p = 0.001) than in inspiration (8.02 ± 1.43 mm). For 78 tracheal collapse dogs, the mean of the TITRW width was greater in expiration (15.89 ± 1.01 mm, p = 0.001) than in inspiration (14.85 ± 1.17 mm). The TITRW/FTRW ratio of the normal dogs was higher (p = 0.001) in expiration (0.81 ± 0.09) than that in inspiration (0.79 ± 0.10). When compared between the normal and tracheal collapse dogs, the TITRW/FTRW ratio was also increased (p = 0.001) both in expiration (1.54 ± 0.09) and inspiration (1.47 ± 0.08), respectively. Based on these results, the cutoff level of the TITRW/FTRW ratio was statistically analyzed according to the receiver operating characteristic curve and it could be set at 1.16 in expiration and at 1.13 in inspiration. We have demonstrated that tracheal ultrasonography is a useful technique for the evaluation of tracheal collapse and it can be a supportive tool together with the radiographic findings for making the correct diagnosis.  相似文献   

14.
Management of fulminant hepatic failure (FHF) continues to be one challenging problem, and experimental animal models resembling its clinical conditions are still needed. Rabbit hemorrhagic disease (RHD) fullfils many requirements of an animal model of FHF. This work investigated changes in MAPK, NF-κB, AP-1 and STAT pathways during RHD-induced liver injury. Rabbits were infected with 2 × 104 hemagglutination units of an RHD virus isolate. Apoptosis was documented by the presence of caspase-3 activity and substantial PARP proteolysis at 36 and 48 h postinfection (pi). Infection induced a marked and maintained expression of TNF-α from 12 h pi, while there was only a transitory increase in IL-6 expression. Expression of phosphorylated (p)-JNK, p-p38 and p-ERK1/2 was significantly elevated at 12 h pi. At 48 h pi p-JNK expression was maintained at a maximum level, while that of p-p38 returned to normality and there was no p-ERK1/2 expression. Activation of NF-κB and AP-1 and increased expression of VCAM-1 and COX-2 were observed. No significant changes were detected in activation of STAT1 and STAT3, while SOCS3 expression increased significantly. The current findings suggest that activation of JNK is an essential component in liver injury mediated by the RHD virus and that lack of activation of STAT3, probably mediated by SOCS3 over-expression, would contribute to the inhibition of the regenerative response. Data show the presence of molecular mechanisms contributing to liver damage and the lack of regeneration and they support the usefulness of this model to investigate novel therapeutical modalities in FHF.  相似文献   

15.
本研究以瑞香狼毒为材料,采用常规营养指标测定方法对其营养成分进行测定。结果表明,瑞香狼毒的干物质(DM)(89.87±0.30)%,灰分(Ash)(5.59±0.62)%,单宁(0.0508±0.0037)%,粗蛋白(CP)(15.00±1.46)%,粗脂肪(EE)(3.47±0.20)%,中性洗涤纤维(NDF)(39.11±0.77)%,酸性洗涤纤维(ADF)(28.7±0.76)%,木质素(ADL)(6.87±0.26)%。同时,其氨基酸和矿质元素种类齐全,含量丰富。研究表明瑞香狼毒各营养成分含量与紫花苜蓿相当,如能实现植株脱毒,则可成为一种潜在的牧草资源。  相似文献   

16.
This study describes the transabdominal ultrasonographic findings in 54 goats with confirmed Johne’s disease (JD). Compared with the control group (0.8 ± 0.4 mm thick), the test group presented with mild (2.8 ± 0.2 mm), moderate (4.2 ± 0.4 mm), and severe (6.9 ± 1.1 mm) thickening of the intestinal wall. The most outstanding ultrasonographic findings were pronounced enlargement of the mesenteric lymph nodes in 49 goats. In 36 goats, the enlarged lymph nodes showed a hypoechoic cortex and a hyperechoic medulla. In 7 goats, the cortex and medulla were hypoechoic. In 5 goats, the cortex and the medulla could not be differentiated. In the remaining cases, the cortex and medulla contained small hypoechoic lesions. Necropsy findings included enlarged mesenteric lymph nodes in 52 goats and thickening of the small intestinal wall in 30 goats. Compared with the postmortem results, the antemortem ultrasound sensitivity in detecting intestinal wall thickness and enlarged mesenteric lymph nodes was 80% and 94%, respectively.  相似文献   

17.
The disposition kinetics of levofloxacin was investigated in six male crossbred calves following single intravenous administration, at a dose of 4 mg/kg body weight, into the jugular vein subsequent to a single intramuscular injection of paracetamol (50 mg/kg). At 1 min after the injection of levofloxacin, the concentration of levofloxacin in plasma was 17.2 ± 0.36 µg/ml, which rapidly declined to 6.39 ± 0.16 µg/ml at 10 min. The drug level above the MIC90 in plasma, was detected for up to 10 h. Levofloxacin was rapidly distributed from blood to the tissue compartment as evidenced by the high values of the distribution coefficient, α (17.3 ± 1.65 /h) and the ratio of K12/K21 (1.83 ± 0.12). The values of AUC and Vdarea were 12.7 ± 0.12 µg.h/ml and 0.63 ± 0.01 l/kg. The high ratio of the AUC/MIC (126.9 ± 1.18) obtained in this study indicated the excellent antibacterial activity of levofloxacin in calves. The elimination half-life, MRT and total body clearance were 1.38 ± 0.01 h, 1.88 ± 0.01 h and 0.32 ± 0.003 l/kg/h, respectively. Based on the pharmacokinetic parameters, an appropriate intravenous dosage regimen for levofloxacin would be 5 mg/kg repeated at 24 h intervals when prescribed with paracetamol in calves.  相似文献   

18.
A bioavailability and pharmacokinetics study of doxycycline was carried out on 30 healthy ostriches after a single intravenous (IV), intramuscular (IM) and oral dose of 15 mg/kg body weight. The plasma doxycycline concentration was determined by HPLC/UV at 0 (pretreatment), 0.08, 0.25, 0.5 1, 2, 4, 6, 8, 12, 24 and 48 h after administration. The plasma concentration-time curves were examined using non-compartmental methods based on the statistical moment theory for only the higher dose. After IV administration, the elimination half-life (t1/2β), mean residence time (MRT), volume of distribution at the steady-state (Vss), volume of distribution (Vdarea) and total body clearance (ClB) were 7.67 ± 0.62 h, 6.68 ± 0.86 h, 0.86 ± 0.16 l/kg, 1.67 ± 0.52 l/kg and 2.51 ± 0.63 ml/min/kg, respectively. After IM and oral dosing, the mean peak plasma concentrations (Cmax) were 1.34 ± 0.33 and 0.30 ± 0.04 µg/ml, respectively, which were achieved at a post-administration time (tmax) of 0.75 ± 0.18, 3.03 ± 0.48 h, respectively. The t1/2β, Vdarea and ClB after IM administration were 25.02 ± 3.98 h, 23.99 ± 3.4 l/kg and 12.14 ± 1.71 ml/min/kg, respectively and 19.25 ± 2.53 h, 61.49 ± 7 l/kg and 40.19 ± 3.79 ml/min/kg after oral administration, respectively. The absolute bioavailability (F) of doxycycline was 5.03 and 17.52% after oral and IM administration, respectively. These results show that the dose data from other animals particularly mammals cannot be extrapolated to ostriches. Therefore, based on these results along with those reported in the literature, further studies on the pharmacokinetic/pharmacodynamic, in vitro minimum inhibitory concentration values and clinical applications of doxycycline in ostriches are required.  相似文献   

19.

Background

Gastric acid suppressants frequently are used in cats with acid‐related gastric disorders. However, it is not known if these drugs effectively increase intragastric pH in cats.

Objectives

To examine the effects of PO administered ranitidine and omeprazole on intragastric pH in cats and to compare the efficacy of once‐daily versus twice‐daily dosage regimens for omeprazole.

Animals

Eight domestic shorthair cats.

Methods

Using a randomized 4‐way cross‐over design, cats were given enteric‐coated omeprazole granules (1.1–1.3 mg/kg q24h and q12h), ranitidine (1.5–2.3 mg/kg q12h), and placebo. Intragastric pH was monitored continuously for 96 hours using the Bravo system1, starting on day 4 of treatment, followed by a median washout period of 12 days. Mean percentage of time pH was ≥3 and ≥4 was compared among groups using repeated measures ANOVA.

Results

Mean ± SD percentage of time intragastric pH was ≥3 and ≥4 was 67.0 ± 24.0% and 54.6 ± 26.4% for twice‐daily omeprazole, 24.4 ± 22.8% and 16.8 ± 19.3% for once‐daily omeprazole, 16.5 ± 9.0% and 9.6 ± 5.9% for ranitidine, and 9.4 ± 8.0% and 7.0 ± 6.6% for placebo administration. Twice‐daily omeprazole treatment significantly increased intragastric pH, whereas pH after once‐daily omeprazole and ranitidine treatments did not differ from that of placebo‐treated cats.

Conclusion and Clinical Importance

Only twice‐daily PO administered omeprazole significantly suppressed gastric acidity in healthy cats, whereas once‐daily omeprazole and standard dosages of ranitidine were not effective acid suppressants in cats.  相似文献   

20.
为寻求控制水土流失适宜坡耕地利用方式,开展如下试验:1) 采用完全随机设计,研究不同坡度(0°、5°和10°)集雨垄的径流效率和临界产流降水量;2) 采用裂区设计,坡度(5°和10°)为主区,耕作模式(传统平作、开敞垄和打结垄)为副区,研究坡地打结垄沟集雨种植对土壤水分、径流、泥沙损失、养分损失、紫花苜蓿干草产量和水分利用效率的影响。结果表明:0°、5°和10°集雨垄的临界产流降水量分别为1.55、1.33和1.00 mm,径流效率分别为88.2%、91.1%和92.7%;与传统平作相比,开敞垄和打结垄的小区径流量分别减少62.3%~67.9%和76.4%~79.9%,小区径流效率分别减少51.0%~54.5%和67.8%~68.2%;泥沙流失量分别减少95.6%~96.4%和98.4%,全氮流失量分别减少95.3%~96.2%和98.1%~98.2%,全磷流失量分别减少95.3%~96.1%和98.2%,有机质流失量分别减少94.1%~95.6%和97.8%~97.9%;开敞垄和打结垄明显增加浅层(0~60 cm)土壤剖面含水量;开敞垄和打结垄紫花苜蓿全年干草产量分别提高40.3%~50.4%和16.0%~18.7%,水分利用效率分别提高4.4~11.5 kg·hm-2·mm-1和2.0~5.3 kg·hm-2·mm-1。坡度10°的径流量、径流效率、小区泥沙流失量、全氮流失量、全磷流失量和有机质流失量分别是坡度5°的1.44、1.40、2.34、2.24、2.39和1.97倍;坡度5°的紫花苜蓿全生育期根系层(0~200 cm)土壤贮水量、紫花苜蓿全年干草产量和水分利用效率分别是坡度10°的1.05、1.28和1.41倍。开敞垄增加紫花苜蓿干草产量和水分利用效率效果最为明显,打结垄减少径流、泥沙流失和养分损失效果最为明显。  相似文献   

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