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991.
992.
A prospective multicenter study was conducted within the National Model Spinal Cord Injury System program to examine neurological deficits and recovery patterns following spinal cord injury (SCI) in individuals with cervical spondylosis and without a spinal fracture. Nineteen patients were evaluated. Sixty-eight percent presented initially with motor incomplete lesions. Of those who presented with motor incomplete injuries at their initial examination, 69 percent had less deficit in the lower than in the upper extremities, indicative of a central cord syndrome. At follow-up, 12 subjects were unable to ambulate, four required assistance and three were able to ambulate independently. On the average, subjects doubled their initial Asia Motor Score (AMS) scores by one year following injury. Residual upper extremity weakness, however, limited the ability to ambulate. Recovery of motor strength in this group is comparable to that of individuals with incomplete tetraplegia in general but the proportion who regain ambulatory function is less.  相似文献   
993.
The internalization of basic fibroblast growth factor (FGF-2) was studied in Chinese hamster lung fibroblasts (CCL39). Recombinant FGF-2 was derivatized with a photoactivable agent, N-hydroxysuccinimidyl-4-azidobenzoate (HSAB), iodinated, and used to visualize intracellular FGF-2-affinity-labeled molecules after internalization at 37 degrees C. Iodinated HSAB-FGF-2 maintained the properties of natural FGF-2 such as affinity for heparin, binding to Bek and Fig receptors, interaction with high- and low-affinity binding sites, and reinitiating of DNA synthesis in CCL39 cells. Affinity-labeling experiments at 4 degrees C with 125I-HSAB-FGF-2 led to the detection of several FGF-cell surface complexes with apparent molecular mass of 80, 100, 125, 150, 170-180, 220, 260, and about 320 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), whereas two specific bands at 80 and 130-160 kDa were obtained using the homobifunctional cross-linking reagent, disuccinimidyl suberate. When the cells, preincubated with 125I-HSAB-FGF-2 at 4 degrees C and then washed, were shifted to 37 degrees C, irradiation of the internalized labeled FGF-2 led to detection of a similar but fainted profile with one major specific band at 80 kDa. Heparitinase II treatment of the cells reduced binding of 125I-HSAB-FGF-2 to its cell surface sites by 80% and internalization by 55%, indicating the involvement of heparan sulfate proteoglycans in these processes. Among the heparitinase-sensitive bands was the 80-kDa complex.  相似文献   
994.
Results are reported on the sensitivity of various gynaecological tumour cell lines to 5-aminolaevulinic acid-induced protoporphyrin IX-sensitised photodynamic therapy (ALA-PDT) in vitro. All cell lines tested accumulated ALA-induced protoporphyrin IX (PpIX) and demonstrated good sensitivity to ALA-PDT. Localisation of PpIX in the mitochondria was demonstrated by fluorescence microscopy. Subcellular damage following ALA-PDT was observed using transmission electron microscopy. This damage was localised initially to the mitochondria, with damage to membranes and the nucleus and complete loss of intracytoplasmic organisation being observed subsequently. There was no apparent difference in ALA-PDT response between a multidrug-resistant ovarian carcinoma cell line and its parent line. These results indicate that ALA-PDT has potential for application to therapy of gynaecological malignancies.  相似文献   
995.
Potential reproductive effects from occupational exposures to ethylene glycol ethers (EGE) are of concern since these organic solvents have been used widely in industry, and their reproductive toxicity has been well documented in animal studies. For determination of whether occupational exposure to EGE was associated with increased risks of spontaneous abortion and subfertility (i.e., taking more than 1 year of unprotected intercourse to conceive), a retrospective cohort study was conducted among workers at two semiconductor manufacturing plants in the eastern United States in 1980-1989 as part of a larger evaluation of reproductive health. Reproductive and occupational histories were obtained from interviews of semiconductor manufacturing workers and spouses. Assessment of potential exposure to mixtures containing EGE (none, low, medium, and high) was based on reported processes and company records. There were 1,150 pregnancies to semiconductor manufacturers, 561 to female employees and 589 to wives of male employees. Among female manufacturers, potential exposure to mixtures containing EGE was associated with increased risks of spontaneous abortion (relative risk in the high exposure group = 2.8; 95% confidence interval (CI) 1.4-5.6) and subfertility (odds ratio in the high exposure group = 4.6; 95% CI 1.6-13.3). Both of these risks exhibited a dose-response relation with potential EGE exposure (p for trend = 0.02). Among spouses of male manufacturers potentially exposed to mixtures containing EGE, there was no increased risk of spontaneous abortion, but there was a nonsignificant increased risk of subfertility (odds ratio in the high exposure group = 1.7; 95% CI 0.7-4.3).  相似文献   
996.
997.
Samples of wheat harvested from 1988 to 1990 and stored in elevators in the south of Brazil (12 Brazilian, 4 Argentinian and 2 Uruguayan) were analysed in 1990 for 14 mycotoxins: deoxynivalenol (DON), nivalenol, diacetoxyscirpenol (DAS), T-2 and HT-2 toxins, T-2 triol, T-2 tetraol, aflatoxins B1, B2, G1, G2, ochratoxin A (OCHRA A), zearalenone and sterigmatocystin. One sample (1988 harvest) was contaminated with OCHRA A (0.04 microgram/g) and three other samples (1990 harvest) were contaminated with DON (0.40 microgram/g), DAS (0.30 microgram/g), T-2 (two samples, 0.35 and 0.36 gamma g/g) and T-2 tetraol (1.68 micrograms/g). Fusarium graminearum Schwabe was found in the 1990 samples with a relative incidence ranging from 1 to 22% and predominated in Argentinian and Uruguayan wheat (1990 harvest). Fusarium dimerum Penzig (8-75%) was the main Fusarium sp. in Brazilian wheat from the 1990 harvest.  相似文献   
998.
999.
We developed an intravenous and oral [13C]galactose breath test for the in vivo study of galactose metabolism. Following an intravenous bolus of 7 mg/kg of [1-13C]galactose in the fasting state, normal children and adults eliminated 3-6% and 21-47% of the bolus as 13CO2 in expired air collected over 1 and 5 h, respectively. Comparable fractional elimination was seen when the dose was given orally. Patients with galactosemia who have barely detectable or absent galactose-1-phosphate uridyltransferase (GALT) activity in erythrocytes and are homoallelic for the Q188R gene mutation, when given a 7 mg/kg intravenous bolus had barely detectable 13CO2 in air samples in the first hour, but eventually eliminated as much as 3.6% of the dose in 5 h. A galactosemia/Duarte (Q188R/N314D) compound heterozygote and a homozygous Duarte subject, as well as a subject with one normal allele and one Q188R allele, showed normal in vivo oxidation. An assessment of whole body galactose metabolism can be made with this procedure. Further use of this in vivo modality in patients with different genetic backgrounds should increase our understanding of genotype-phenotype relationships in hereditary galactosemia.  相似文献   
1000.
The author discusses problems in compiling and evaluating data and recommends a standard protocol for determing yield of food. The recent extensive revision of Agriculture Handbook No. 102, Food Yields Summarized by Different Stages of Preparation, points up the urgent need for guidelines and a standard protocol.  相似文献   
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