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141.
142.
Three sequential experiments were conducted with rabbits to 1) determine the effect of endophyte-infected (E+) tall fescue seed on rabbit performance and examine the effect of anti-ergot alkaloid immunization on rabbit performance and protectiveness against fescue toxicosis, 2) compare immunogens designed to elicit systemic anti-ergot alkaloid antibodies, and 3) select a superior adjuvant. In Exp. 1, rabbits (n = 6/treatment) fed E+ fescue seed diets (20%, 340 ppb total ergot alkaloids) had reduced (P < .05) intake and weight gain compared with endophyte-free (E-) controls, whereas apparent diet digestibility was not different between E+ and E-. Rabbits immunized against ergot alkaloids (E+ vac) with lysergol conjugated to human serum albumin (Ly-HSA) had greater (P < .05) intake than E+ rabbits during the wk 1 of a 3-wk dietary challenge. In Exp. 2, rabbits (n = 4/treatment) were immunized with Ly-HSA, with H100-B (ergot alkaloid hapten, H100-different protein carrier, B conjugate), or combinations of both with alum as adjuvant. Greatest (P < .001) anti-ergot alkaloid antibody (Ab) titer developed in the group immunized with H100-B. In Exp. 3, rabbits (n = 4/treatment) were immunized with the immunogen H100-B in conjunction with six adjuvants. Freund's incomplete adjuvant (FIA) in combination with DEAE-dextran and FIA alone gave highest anti-ergot titers. In summary, rabbit weight gain and intake were reduced by feeding E+ fescue seed diets, immunization against ergot alkaloids provided temporary improvement in intake, and H100-B conjugate with FIA or FIA + DEAE-dextran as adjuvants elicited a superior anti-ergot immune response. We believe that rabbits may serve as a model animal for fescue toxicosis research.  相似文献   
143.
Autoimmunity can manifest clinically in many ways; however, despite the various efforts to classify autoimmune disorders into specific disease entities, the borders between these disorders remain, in many cases, unclear. In this report we describe a young woman with subclinical Sj?gren's syndrome and biliary cirrhosis, who presents clinically with symptoms exclusively from the central nervous system. This neurological syndrome is consistent with a progressive myelopathy. Although the patient has a serologically and histologically confirmed multisystemic autoimmune disorder, she fulfills none of the classification criteria for the diagnosis of a specific connective tissue disease.  相似文献   
144.
The effect of moderately high dietary zinc (Zn) on the activities of plasma (PL) ceruloplasmin (CP), and PL and erythrocyte (RBC) copper (Cu), Zn superoxide dismutase (SOD) was determined in weanling rats fed Cu-deficient (DEF; < 1 mg Cu/kg), marginal (MAR; 2 mg Cu/kg), or control (CON; 5 mg Cu/kg) copper diets containing normal or high Zn (HZn; 60 mg/kg) for 4 wk and supplemented with oral Cu (CuS; 5 mg/L) in drinking water for 0, 1, 3, or 7 d. PL Cu decreased (67% compared to CON; p < or = 0.05) in the DEF and increased to control level after 3 d of CuS; increased in the MAR group after 1 d of CuS. HZn reduced overall PL Cu by 27% in all groups, but did not alter the linear increase in PL Cu between 0 and 3 d of Cu S. PL CP activity altered concomitantly with PL Cu levels: The time course of increase in CP activity after 0-3 d of CuS was not influenced by HZn in the diet and CP declined in the DEF group by 92%. There was no correlation between dietary Cu level and PL CP. PL SOD activity decreased by 46% (p < or = .05) in the DEF group, increased to control activity after 1 d of CuS and declined slightly after 7 d; MAR diet did not alter PL SOD. HZn diet increased PL SOD activity in all groups by 150%, reduced activity in the DEF and MAR groups by 65 and 37% and delayed the recovery of PL SOD after CuS. RBC SOD declined in the DEF and MAR groups by 56 and 33% (p < or = 0.05) and did not respond to CuS; HZn diet did not influence RBC SOD activity. These data indicate that moderately high Zn in the diet reduces PL Cu, but not PL CP activity or the recovery of PL Cu or CP activity after oral CuS of Cu-deficient rats, modifies the response of PL SOD to dietary Cu, but does not influence RBC SOD activity.  相似文献   
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146.
We established in culture two colony clones of rMTC 44-2 cells, rMTC 44-2B and 44-2C which secrete substantially greater quantities of neurotensin (NT) than the parent cell line. We describe here the effects of the synthetic glucocorticoid, dexamethasone, on NT and cAMP release. Medium and intracellular levels of NT and cAMP were measured by specific RIAs. Long-term release experiments were performed in Dulbecco's Modified Eagle's Medium supplemented with 15% horse serum (DMEM). Short-term release experiments were performed in Krebs-Ringer-bicarbonate-glucose buffer (KRBG) supplemented with 1.0 mm Ca2+. Dexamethasone stimulated NT release and increased intracellular NT levels. The ED50 values for stimulation of NT release following 24 or 48 h incubation of cells in DMEM with dexamethasone were 5 X 10(-9) and 7 X 10(-9) M, respectively. Dexamethasone markedly enhanced intracellular levels of NT in rMTC 44-2 cells while it decreased cell growth. Cells pretreated with dexamethasone for 48 h released greater amounts of NT in response to Ca2+ (1.0 mM) with or without K+ (50 mM) or NE (10(-6) M) following a 10 min incubation with these substances in KRBG. This experimental paradigm was also used to measure the efflux of cAMP following a brief (10 min) exposure of cells to NE. We conclude that the rMTC 44-2B and 44-2C cells are useful tools for studying the effects of dexamethasone on the regulation of cell growth, as well as the secretion of NT and cAMP.  相似文献   
147.
The various leukemias in Hokkaido for the past 20 years are analysed in its change of the mortality rate, the type of leukemia, and the clinical picture. The observation years are divided into 4 periods: I (1951-1957), II (1958-1962), III (1963-1967), IV (1968-1972). 1. The adjusted mortality rate of leukemia shows a rising tendency through these periods: I (1.7), II (3.0), III (3.5), IV (3.6). 2. The adjusted age-specific mortality rate of leukemia in period II, III, and IV, show a remarkable increase in all age brackets compared with period I, especially in older age brackets. The rate of the "60-69 years old" bracket gradually rises as I (3.1), II (4.8), III (5.9), IV (7.2). The rate of the "over 70 years old" bracket is I (1.3), II (1.8), III (5.0), IV (9.3). It is characteristic that these brackets has the highest mortality rate in period IV. 3. Some comparisons between period I and IV are described as follows: (1). Monocytic leukemia had decreased from 10.6% (I) to 1.4% (IV) and chronic myelogenous leukemia has slightly increased in period IV. (2). In acute type, the cases of aleukemic leukemia tends to increase in period IV and its initial symptoms changes into mild gradually. (3). In chronic type in period IV, splenomagaly is common in the initial symptom and while blood cell counts in these cases are above 10 x 10(4)/cmm.  相似文献   
148.
INTRODUCTION: New possibilities for transcatheter treatment of the cardiovascular system are guaranteed with the improvement of materials and the availability of new devices. Nevertheless, a rationalization of the potential activity in this sector seems to be necessary, and it could arise through the presence of Catheterization Laboratories "open" to diagnostic procedures and therapy that are not confined to the coronary system. This clinical study reports the experiences and results of our work in this field. MATERIALS AND METHODS: During the period from May 1995 to May 1997, our laboratory performed 205 diagnostic procedures that did not involve the coronary system. Based on this diagnostic work, there emerged 91 cases with an indication for transcatheter intervention, which was subsequently performed at our laboratory. There were 68 peripheral angioplasty procedures on the iliofemoral axis, 2 angioplasties of the subclavian artery, 8 of the renal artery, 2 procedures involving the treatment of A-V fistulas, one case of femoral pseudoaneurysm treatment and 10 cases of transcutaneous pericardiotomy performed with a balloon catheter. All the procedures were performed by our laboratory staff using materials that are normally at our disposal. RESULTS: Successful results were obtained in 65 out of the 68 peripheral angioplasty procedures and in all of the 8 renal and 2 subclavian angioplasties. The positioning of the endoprosthesis for the closure of the A/V fistula was effective in one of the two cases. The transcatheter treatment of the femoral pseudoaneurysm was successful. In all cases where a pericardiotomy was performed with a balloon catheter, there was no reoccurrence of cardiac tamponade during the follow-up period. No complications were noted as a result of any of the procedures. CONCLUSIONS: Our experience documents how it is possible to increase the diagnostic and therapeutic options in a Catheterization Laboratory. However, willingness on the part of the staff to update their skills continually and collaborate with other specialists is necessary in order to maintain optimal operative standards.  相似文献   
149.
A new-technology cigarette has been developed. While the new cigarette burns some tobacco, it does not use tobacco as the fuel to sustain combustion and provide heat to the cigarette. Rather, the new cigarette primarily heats tobacco thereby reducing products of smoke formation mechanisms such as tobacco combustion, tobacco pyrolysis and pyrosynthesis. The mainstream smoke composition from a cigarette based on the new design (TOB-HT) has been characterized in comparative chemical testing with two reference cigarettes using the FTC puffing regimen. Thermal properties, UV absorption characteristics, elemental composition and materials balance studies all suggest a simplified smoke aerosol. Twenty-five smoke constituents ("target compounds") identified by the scientific community as compounds that may contribute to the diseases statistically associated with smoking have also been measured. Mainstream smoke concentrations of most target compounds are significantly lower with the TOB-HT cigarette when compared with reference cigarettes in the ultra-light "tar" and light "tar" categories. Taken together, chemical analysis results suggest simplified TOB-HT smoke chemistry with marked reductions in specific chemicals reported to be biologically active.  相似文献   
150.
BACKGROUND: Many experts have suggested that blunt splenic trauma in patients older than 55 years should not be managed by observation because of supposed increased fragility of the spleen and decreased physiologic reserve in elderly patients. We sought to determine the outcome of nonoperative management of blunt splenic trauma in patients older than 55 years. METHODS: For the years 1994 through 1996, data for patients with splenic injury older than 55 years from seven trauma centers in a single state were reviewed. RESULTS: Blunt splenic trauma occurred in 41 patients older than 55 years. Eight patients were excluded from further analysis because of death from massive associated injuries within 24 hours of admission. The remaining 33 patients (mean age, 72+/-10 years) were divided into two groups: immediate exploration (10 patients) and observation (23 patients). Observation of blunt splenic injury failed in 4 of 23 patients (17%). No patient deaths were related to the method of management of the splenic injury. CONCLUSIONS: Observation of the elderly patient with blunt splenic trauma has an acceptable failure rate of 17%.  相似文献   
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