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41.
Fractures of the femur in newborn calves   总被引:1,自引:1,他引:0       下载免费PDF全文
A retrospective study of femoral fractures in 77 calves revealed that most occurred in the femoral shaft or in the proximal physis, with thin cortices and periosteal stripping significant problems in fractures of the femoral shaft. Most cases were related to forced extraction, with more left femurs being affected than right. The existence of concurrent disease reduced the success rate by 50% and, when significant additional trauma was present, no calves survived. When all cases were considered regardless of condition, the “longterm” success rate was 43%.  相似文献   
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Background

Central renin angiotensin system has an important role on the cerebral microcirculation and metabolism. Our previous work showed that inhibition of angiotensin converting enzyme () activity prior to induction of ischemia protected the brain from severe ischemia/reperfusion (I/R) injuries. This study evaluated the impacts of post-ischemic inhibition of , enalapril, on brain infarction in normotensive rats.

Methods

Rats were anesthetized with chloral hydrate (400 mg/kg). Focal cerebral ischemia was induced by 60-min intraluminal occlusion of right middle cerebral artery (MCA). Intraperitoneal injection of enalapril (0.03 or 0.1 mg/kg) was done after MCA reopening (reperfusion). Neurological deficit score (NDS) was evaluated after 24 h and the animals randomly assigned for the assessments of infarction, absolute brain water content (ABWC) and index of brain edema

Results

Severe impaired motor functions (NDS = 2.78 ± 0.28), massive infarction (cortex = 214 ± 19 mm3, striatum = 86 ± 5 mm3) and edema (ABWC = 83.1 ± 0.46%) were observed in non-treated ischemic rats. Non-hypotensive dose of enalapril (0.03 mg/kg) significantly reduced NDS (1.5 ± 0.22), infarction (cortex = 102 ± 16 mm3, striatum = 38 ± 5 mm3) and edema (ABWC = 80.9 ± 0.81%). Enalapril at dose of 0.1 mg/kg significantly lowered arterial pressure could not improve NDS (2.0 ± 0.45) and reduce infarction (cortex = 166 ± 26 mm3, striatum = 71 ± 11 mm3).

Conclusion

Post-ischemic ACE inhibition in the normotensive rats without affecting arterial pressure protects the brain from reperfusion injuries; however, this beneficial action is masked by hypotension. Key Words: Angiotensin converting enzyme (ACE) inhibitors, Enalapril, Brain edema, Cerebral infarction  相似文献   
44.
The aim of this research is to study the feasibility of removing nitrates from water by means of anion exchange. In the purposed work an attempt was made to utilize strong basic anion resin to remove nitrate in the presence of competitive anion. Amberjet Cl- 4200 ion exchange resin was used in a batch scale. The fixation rate of nitrate without the presences of any competitive anion was almost constant (94.60-96.43) when the nitrate concentrations are in the range of 100-150 mg L(-1). The fixation rate of nitrate in the presences of two competitive anions (sulphate and chloride) was reduced to 82% when the concentration of nitrate was 100 mg L(-1).  相似文献   
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We sought to determine the ultrastructure of pancreatic islet beta cells of streptozotocin-induced diabetic rats treated with oral vanadyl sulphate. Diabetes was induced in male Wistar rats by intravenous injection of 40 mg kg(-1) streptozotocin. The same volume of normal saline was injected in sham animals. Animals were divided into treated and control groups. Vanadyl sulphate was added to the drinking water of the treated animals at a concentration of 1 mg mL(-1) up to three months. Two months after vanadyl sulphate withdrawal animals were killed. Ultrastructure of islet beta cells were studied by transmission electron microscope. In diabetic treated rats plasma glucose and fluid intake returned to normal levels within three months while control animals remained diabetic. Well granulated cytoplasm, well developed endoplasmic reticulum, increase in the number of immature granules in the cytoplasm with no clear signs of cell injury were found in the islet beta cells of diabetic treated rats. Lymphocyte filteration, nuclear picnosis, cytoplasmic vacuolization were found frequently in the islet beta cells of untreated diabetic rats. In conclusion as was evident in thin sections of panceatic islet beta cells of treated diabetic rats in this study, vanadyl sulphate through preserving islet beta cells structure and ultrastructure contributes in reversing diabetic signs and symptoms in streptozotocin induced diabetic rats.  相似文献   
47.
A complete diallel cross study of six local populations of Iranian melon (Eyvanaki, Abasali, Tashkandi, Hose-sorkh, Mashhadi and Nahavand) and one foreign cultivar (Ananasi) was carried out. We investigated maturity, average weight per fruit, yield and acceptable yield in the pruning conditions over a period of two planting seasons. The analysis of variance for all of the characteristics indicated highly significant differences among genotypes. Additive gene effects were most important with respect to average weight per fruit and yield, while genetic dominance effects mainly controlled fruit maturity and acceptable yield. The reciprocal effects were significant for yield, acceptable yield and fruit maturity. Nahavand and Tashkandi had significant positive general combining ability effects for yield and acceptable yield. Favourable heterosis over the better parent was found for average weight per fruit, yield and acceptable yield. Thus, there is the potential to generate superior cultivars in segregant generation and hybrid production.  相似文献   
48.
Journal of Crop Science and Biotechnology - Salinity stress is one of the most important abiotic stresses which reduce crop production worldwide. In this study, 17 morphological and agronomic...  相似文献   
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50.

Background:

Oral vanadyl sulfate (vanadium) induces normoglycemia, proliferates beta cells and prevents pancreatic islet atrophy in streptozotocin-induced diabetic rats. Soteriological method is used to quantitate the proliferative effects of vanadium on beta-cell numbers and islet volumes of normal and diabetic rats.

Methods:

Adult male Sprague-Dawley rats were made diabetic with intravenous streptozotocin injection (40 mg/kg). Normal and diabetic rats were divided into four groups. While control normal and diabetic (CD) groups used water, vanadium-treated normal (VTN) and diabetic (VTD) groups used solutions containing vanadyl sulfate (0.5-1 mg/mL, VOSO4+5H2O). Tail blood samples were used to measure blood glucose (BG) and plasma insulin. Two months after treatment, rats were sacrificed, pancreata prepared, and stereology method was used to quantitatively evaluate total beta cell numbers (TBCN) and total islet volumes (TISVOL).

Results:

Normoglycemia persisted in VTN with significantly decreased plasma insulin (0.190.08 vs. 0.970.27 ng/dL, P<0.002). The respective high BG (53249 vs. 14446 mg/dL, P<0.0001) and reduced plasma insulin (0.260.15 vs. 0.540.19 ng/dL, P<0.002) seen in CD were reversed in VTD during vanadium treatment or withdrawal. While the induction of diabetes, compared to their control, significantly decreased TISVOL (1.90.2 vs. 3.030.6 mm3, P<0.003) and TBCN (0.990.1 vs. 3.20.2 x 106, P<0.003), vanadium treatment significantly increased TISVOL (2.90.8 and 4.071.0 mm3, P<0.003) and TBCN (1.50.3 and 3.80.6 x 106, P<0.03).

Conclusion:

Two-month oral vanadium therapy in STZ-diabetic rats ameliorated hyperglycemia by partially restoring plasma insulin. This action was through proliferative actions of vanadium in preventing islet atrophy by increasing beta-cell numbers.Key Words: Vanadium, Pancreas, Islet volumes, Rats  相似文献   
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