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Thirty-two Holstein cows (8 primiparous) were assigned to negative control or to one of three treatments to assess three forage harvesting and conservation techniques. Forage was harvested as low moisture silage by either a cylinder-type forage harvester, a self-loading forage harvester, or a round baler. Treatment diets were fed from wk 4 to 15 of lactation and consisted of silages harvested by the respective methods supplemented with concentrate at 1.1% of BW. Unsupplemented silage harvested by a cylinder-type forage harvester was used as a control. Daily DMI was higher for cows fed supplemented heap silage cut with either a cylinder-type forage harvester (23.7 kg) or a self-loading forage harvester (22.6 kg) than for cows fed the control (20.0 kg) or supplemented round bale silage (20.1 kg). Milk yield was highest for cows fed supplemented heap silage cut with a cylinder-type forage harvester (26.6 kg/d) and lower for those fed supplemented heap silage cut with a self-loading forage harvester (22.7 kg/d) or the control (20.8 kg/d). Milk composition and digestibilities of DM, N, ADF, and energy were similar among treatments. Postfeeding NEFA concentration decreased more for control cows than for those fed supplemented silage, which was related to greater BW loss. The high milk yield for cows fed supplemented heap silage cut with a cylinder-type forage harvester could be related to a high DMI and low BW gain.  相似文献   
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Cognitive and psychomotor impairments can be unwanted adverse effects of antiepileptic drugs. The present double-blind, cross-over study with healthy volunteers was designed to assess the effects of two doses of oxcarbazepine (OXCZ) (150 mg b.i.d.; 300 mg b.i.d.) and a placebo, each given over a two week period. Twelve subjects completed a battery of tests before and 4 h after morning doses on days 1, 8 and 15. Results of objective tests indicated that OXCZ improved performance on a focussed attention task and increased manual writing speed. Subjective ratings showed OXCZ increased feelings of altertness, clear-headedness and quickwittedness. OXCZ had no effect on the range of long-term memory processes assessed in this study. It is concluded that at the doses employed, OXCZ has a slightly stimulant effect on some aspects of psychomotor functioning.  相似文献   
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To evaluate the therapeutic effects of high dose pulse oral calcitrol, 3.5 micrograms calcitrol three times a week and calcium carbonate were administered to 13 patients with end-stage renal disease on chronic hemodialysis with hyperparathyroidism refractory to conventional calcitrol therapy. Serum parathyroid hormone and osteocalcin were detected by radioimmunoassay. Serum parathyroid hormone level of the patients decreased from 1111 +/- 344 ng/L to 492 +/- 218 ng/L by 57.5 +/- 11.5 percent (P < 0.01) in 6 months after the beginning of treatment. Both serum alkaline phosphatase and osteocalcin levels declined markedly, and correlated positively with that of parathyroid hormone. Plasma calcium concentration was markedly elevated, but no obvious increase of plasma phosphate was found. High dose pulse oral calcitrol was effective on secondary hyperparathyroidism. During the course of treatment timely and individual adjustment of calcitrol dose and dialysate calcium concentration is essential.  相似文献   
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Gallstones are common and occur asymptomatically or symptomatically with or without complications. Treatment is only required for symptomatic gallstones and complications in gallstones. Laparoscopic cholecystectomy is the treatment of choice for symptomatic gallstones and is performed with an increasing frequency. One may fear, that the indications for cholecystectomy have changed, and surgery is now undertaken for a lesser degree of morbidity. Cholecystectomy does not increase life expectancy, and 20-30% of patients cholecystectomized for symptomatic gallstones complain of abdominal pain of unknown origin after the operation. New valid parameters in order to predict which patients will benefit from cholecystectomy are therefore necessary. Symptoms specific to gallstones are not precisely known, and greatest success in treatment seems to be related to the occurrence of severe, often steady pain, of hours' duration, often located in the epigastrium or upper right quadrant, with or without radiation and/or vomiting. Dyspepsia alone is not an indication for cholecystectomy. Psychological vulnerability may predict a poor outcome after cholecystectomy and should lead to reconsideration of the indication for surgery.  相似文献   
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Vascular endothelial growth factor (VEGF) expression in various cell types is induced by hypoxia and other stimuli. VEGF mediates endothelial cell proliferation, angiogenesis, vascular growth, and vascular permeability via the endothelial cell receptors, kinase insert domain-containing receptor (KDR)/fetal liver kinase 1 (Flk-1) and FLT-1. Alanine-scanning mutagenesis was used to identify a positively charged surface in VEGF that mediates binding to KDR/Flk-1. Arg82, Lys84 and His86, located in a hairpin loop, were found to be critical for binding KDR/Flk-1, while negatively charged residues, Asp63, Glu64, and Glu67, were associated with FLT-1 binding. A VEGF model based on PDGFb indicated these positively and negatively charged regions are distal in the monomer but are spatially close in the dimer. Mutations within the KDR site had minimal effect on FLT-1 binding, and mutants deficient in FLT-1 binding did not affect KDR binding. Endothelial cell mitogenesis was abolished in mutants lacking KDR affinity; however, FLT-1 deficient mutants induced normal proliferation. These results suggest dual sets of determinants in the VEGF dimer that cross-link cell surface receptors, triggering endothelial cell growth and angiogenesis. Furthermore, this mutational analysis implicates KDR, but not FLT-1, in VEGF induction of endothelial cell proliferation.  相似文献   
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A 44-year-old man with a St. Jude mitral valve was admitted because of progressive pulmonary edema. He was diagnosed with prosthetic heart valve thrombosis (PHVT) based on the findings of "muffled" prosthetic valve clicks. Doppler echocardiographic evidence of severe mitral stenosis and transesophageal echocardiographic evidence of limited mitral valve motility. Because the patient hesitated to undergo our recommended surgical treatment, he was immediately treated with intravenous recombinant tissue plasminogen activator (100 mg over 3 h) followed by heparinization. Two hours after the thrombolytic therapy, the prosthetic valve clicks became clearly audible and his congestive symptoms were dramatically improved. Follow-up echocardiography no longer-showed significant mitral valve obstruction. A transient cerebral ischemic attack occurred at the end of thrombolytic therapy but there were no neurologic sequalae. The patient, on warfarin therapy, was well at follow-up 8 months after discharge. Surgical intervention has long been the standard therapy for patients with PHVT. Our case experience suggests that thrombolytic therapy may be considered as an effective alternative to surgical intervention for selected patients with PHVT. In this report, we also review the current literature regarding the indications, effectiveness and safety of thrombolytic therapy in PHVT.  相似文献   
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