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81.
Quantitative buffy coat (QBC) analysis has been reported to have a high degree of methodical sensitivity in the detection of human filariasis. This study was conducted to evaluate its usefulness in the diagnosis of filariasis using a Dirofilaria immitis/dog model. By necropsy of 244 stray dogs, 40.6% of the animals were found to harbor 1-58 worms of D. immitis (mean 6.5 +/- 8.4 worms/infected dog). The QBC analysis and thick blood smear (TBS) method detected microfilaremia in 31.6% and 21.3% of these dogs, respectively. The results of these two methods were highly correlated with the presence of bisexual worms in the dogs. The QBC analysis was more sensitive (55% versus 39%) and efficient (79% versus 72%) than the conventional TBS method. However, accurate speciation of the microfilariae was impossible using the QBC analysis. Although this technique is more sensitive, simpler, and less time-consuming and does not require as much skill or experience in comparison with the conventional TBS method, the failure in speciation of the parasites may limit its usefulness.  相似文献   
82.
Spontaneous intracranial hypotension is an unusual syndrome of postural headache and low cerebrospinal fluid pressure without an established cause. We present four cases, analyze those previously reported in the literature, examine the MRI, CT, angiographic and cisternographic finding and discuss the clinical picture, proposed pathophysiologic mechanisms and potential treatment.  相似文献   
83.
As reported before, the metabolic activity of nucleus basalis neurons is reduced significantly in Alzheimer patients. Because the apolipoprotein E (ApoE) epsilon4 genotype is a major risk factor for Alzheimer's disease (AD), we determined whether the decrease in metabolic activity in nucleus basalis neurons in AD is ApoE-type dependent. The size of the Golgi apparatus (GA) was determined as a measure of neuronal metabolic activity in 30 controls and 41 AD patients with a known ApoE genotype by using an image analysis system in the nucleus basalis of Meynert. A polyclonal antibody directed against MG-160, a sialoglycoprotein of the GA, was used to visualize this organelle. There was a very strong reduction in the size of the GA in the nucleus basalis of AD patients. Furthermore, a strong and significant extra reduction in the size of the GA was found in the nucleus basalis neurons of AD patients with either one or two ApoE epsilon4 alleles compared with Alzheimer patients without ApoE epsilon4 alleles. Our data show that the decreased activity of nucleus basalis neurons in AD is ApoE epsilon4 dependent and suggest that ApoE epsilon4 participates in the pathogenesis of AD by decreasing neuronal metabolism.  相似文献   
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Protein shedding, or the proteolytic cleavage of a protein from the surface of a cell, is emerging as an important mechanism in the regulation of cellular activity but it is poorly understood. Growing evidence suggesting that protein shedding and protein function are closely linked may lead to new strategies for the treatment of a wide range of diseases.  相似文献   
86.
Migration of non-volatile and volatile compounds from 'microwave and roasting bags' (MRB), made of Nylon 6,6 (and some Nylon 6), into chicken meat, skin, and juices during roasting (200 degrees C/2 h) in a conventional oven was determined. For measurement of migration of non-volatile compounds, cooked chicken was freeze-dried, extracted with methanol after addition of 2-azacyclononane (internal standard) and the extract cleaned-up using liquid-solid adsorption chromatography (silica gel). High performance liquid chromatography (HPLC) in the reverse phase mode using a linear gradient of methanol in water was used to quantify seven Nylon 6 and Nylon 6,6 cyclic monomers and oligomers of molecular mass up to 678 daltons. Migration into chicken was 7.48 micrograms/g (8.26 mg/bag; 3.94 micrograms/cm2), 16% of the total non-volatile compounds contained in the MRB material. Individual migrants were also quantified. Migration of one volatile compound, 2-cyclopentyl cyclopentanone, into the roast chicken parts was measured. Extraction with diethyl ether, using a modified Likens-Nickerson system of concurrent steam distillation-solvent extraction with an internal standard (cyclohexanone) was performed for 10 h. Gas chromatography/mass spectrometry (GC/MS) in the selected ion mode (SIM) was used for quantification. An average of 14.0 (+/- 4.36) micrograms/bag (or micrograms/chicken) migrated, being 0.08% of the total 2-cyclopentyl cyclopentanone present in MRB. Loss of volatile compounds to the atmosphere is believed to have occurred since there was another, more volatile compound (cyclopentanone), present in MRB, at levels higher than 2-cyclopentyl cyclopentanone, but this was not detected in roast chicken. In general, the transference of MRB components into roast chicken can be considered not to present a hazard.  相似文献   
87.
SBMV-S is a resistance-breaking mutant of an Arkansas isolate of the bean strain of southern bean mosaic virus (SBMV-BARK) that is able to move systemically in Phaseolus vulgaris cvs. Pinto and Great Northern, whereas the wild-type SBMV-BARK causes local necrotic lesions and is restricted to the inoculated leaves of these hosts. Sequence analysis of the 4136 nucleotide genomes of SBMV-BARK and SBMV-S revealed seven nucleotide differences, but only four deduced amino acid changes. A single amino acid change occurred in the C-terminal region of the putative RNA-dependent RNA polymerase and three differences were identified in the N-terminal portion of the virus coat protein. SBMV-BARK and SBMV-S were compared with other sobemoviruses and were found to contain a high level of nucleotide sequence identity (91.3%) to SBMV-B. Unlike SBMV-B however, SBMV-BARK and SBMV-S contained four putative overlapping open reading frames, making them more similar in genome organization to the cowpea strain, SBMV-C. The possibility exists that mutations or even errors, that resulted in mis-identification of open reading frames, occurred in previously published information on nucleotide sequence and genomic organization for SBMV-B.  相似文献   
88.
OBJECTIVE: To study the effect of adjuvant chemotherapy after curative hepatic resection in patients with hepatocellular carcinoma. DESIGN: A randomized controlled trial. SETTING: A tertiary referral center. PATIENTS: During a 54-month period, 142 patients with hepatocellular carcinoma underwent hepatic resection at 1 institution. Sixty-six patients who survived the operation and had no demonstrable evidence of residual disease on ultrasonographic examination and hepatic angiographic testing at 1 month after surgery agreed to participate in the study. The median follow-up time was 28.3 months. INTERVENTION: Thirty patients received a combination of intravenous epirubicin hydrochloride (8 doses of 40 mg/m2 each at 6-week intervals) and transarterial chemotherapy using an emulsion of iodized oil and cisplatin (3 courses with a maximum dose of 20 mL each at 2-month intervals). Thirty-six patients had no adjuvant treatment. MAIN OUTCOME MEASURES: Recurrence rate and disease-free survival. RESULTS: A total of 138 courses of intravenous epirubicin was given to the 30 patients. Sixty-one courses of transarterial chemotherapy were given to only 29 of the 30 patients assigned to the treatment group, because the hepatic artery in 1 patient was thrombosed. Six patients (20%) had chemotherapy-related complications with no mortality. Twenty-three of 30 patients in the treatment group and 17 of 36 patients in the control group had recurrences (P=.01). Patients who received adjuvant chemotherapy had a higher incidence of extrahepatic metastases (11 patients vs 5 patients; P=.03). The respective disease-free survival rates at 1, 2, and 3 years were 50%,36%, and 18% for the treatment group and 69%, 53%, and 48% for the control group (P=.04). CONCLUSION: In a group of patients who underwent curative resection of hepatocellular carcinoma, postoperative adjuvant chemotherapy using the present regimen was associated with more frequent extrahepatic recurrences and a worse outcome.  相似文献   
89.
We investigated heat tolerance and growth rate in two trials under ambient conditions in central Florida. Trial 1 (1994) involved 38 Brahman (B), 21 Senepol (S), 19 B x Angus (A), 20 S x A, and 20 Tuli (T) x A heifers. Trial 2 (1995) involved 13 A, 35 B, 30 S, 23 B x A, 17 S x A, and 28 T x A heifers. Measurements were made on three consecutive weeks during the hotter and cooler seasons of each year and included rectal temperature (RT, degrees C), respiration rate (RR, bpm), temperament score (TS; 1 = very docile, 5 = very aggressive), blood packed-cell volume (PCV), and plasma cortisol concentration (CORT). Data for RT were transformed (log10 [RT - 37]) before analysis. On the hottest date in Trial 1, log10 RT was not different between B (.39 +/- .011) and B x A (.37 +/- .016) or between T x A (.35 +/- .015) and B x A, but log10 RT was lower (P < .05) in S x A (.30 +/- .015) than in either S (.35 +/- .015) or T x A. On all dates in Trial 1, RR was lower (P < .05 to .001) and PCV was higher (P < .05 to .001) in B than in B x A. There were few differences in TS except on two dates when B scored higher (P < .01 to .001) than B x A, and these differences were associated with higher (P < .05) CORT in B than in B x A. Using initial BW as a covariate, adjusted ADG (kg) of T x A (.52 +/- .023) was not different from adjusted ADG of B x A (.57 +/- .024) or S x A (.54 +/- .023). On the hottest date in Trial 2, log10 RT and RR were higher (P < .001) in A (.59 +/- .017, 74 +/- 2.7) than in B (.47 +/- .010, 39 +/- 1.6), S (.42 +/- .011, 50 +/- 1.8), and crossbred heifers (.47 +/- .011, 60 +/- 1.8; .43 +/- .014, 55 +/- 2.4; and .50 +/- .012, 48 +/- 2.0 for T x A, S x A and B x A, respectively), and RR was higher (P < .001) in B x A than in B. On the coolest date in Trial 2, RR was slightly lower in B (32 +/- .5) than in A(34 +/- .7, P < .01) and B x A (36 +/- .6, P < .001) and was associated with higher PCV in B than in A. On both dates, TS and CORT were higher (P < .01) in B than in A. In Trial 2, adjusted ADG (kg) was higher (P < .01) in B (.43 +/- .017) than in A (.32 +/- .033), higher (P < .001) in S (.45 +/- .018) than in A, and higher (P < .001) in crossbreds (B x A [.53 +/- .023] + S x A [.44 +/- .025] + T x A [.46 +/- .019]) than in A. These data indicate that heat tolerance in F1 crosses of tropically adapted breeds (Tuli, Senepol, Brahman) with a temperate breed (Angus) is similar to heat tolerance displayed by purebred tropical breeds (Senepol, Brahman).  相似文献   
90.
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