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991.
Sorghum and corn breeding lines were grown in soil in field and greenhouse experiments with and without an inoculum of N2-fixing in Spirillum strains from Brazil. Estimated rates of N2 fixation associated with field-grown corn and sorghum plants were less than 4 g of N2/ha per day. The mean estimated N2-fixation rates determined on segments of roots from corn inoculated with Spirillum and grown in the greenhouse at 24 to 27 degrees C were 15 g of N2/ha per day (16 inbreds), 25 g of N2/ha per day (six hybrids), and 165 g of N2/ha per day for one hybird which was heavily inoculated. The corresponding mean rates determined from measurements of in situ cultures of the same series of corn plants (i.e., 16 inbreds, six hybrids, and one heavily inoculated hybrid) were 0.4, 2.3, and 1.1 g of N2/ha per day, respectively. Lower rates of C2H2 reduction were associated with control corn cultures which had been treated with autoclaved Spirillum than with cultures inoculated with live Spirillum. No C2H2 reduction was detected in plant cultures treated with ammonium nitrate. Numbers of nitrogen-fixing bacteria on excised roots of corn plants increased an average of about 30-fold during an overnight preincubation period, and as a result acetylene reduction assays of root samples after preincubation failed to serve as a valid basis for estimating N2 fixation by corn in pot cultures. Plants grown without added nitrogen either with or without inoculum exhibited severe symptoms of nitrogen deficiency and in most cases produced significantly less dry weight than those supplied with fixed nitrogen. Although substantial rates of C2H2 reduction by excised corn roots were observed after preincubation under limited oxygen, the yield and nitrogen content of inoculated plants and the C2H2-reduction rates by inoculated pot cultures of corn, in situ, provided no evidence of appreciable N2 fixation. 相似文献
992.
HJ Gilfrich 《Canadian Metallurgical Quarterly》1976,29(10):229-236
993.
A 37-year-old woman was found to have pericarditis during the course of a Mycoplasma pneumoniae infection which also produced primary atypical pneumonia. Intrafamily spread of the infection was observed, with varying clinical manifestations. The case is described because there appears to be little information on mycoplasma pericarditis. 相似文献
994.
Rabbit spermatozoa stored at 37 degrees C for 5 hr, 5 degrees C for 5 hr or 5 days, and-196 degrees C for 5 hr, 5 days, or 1 year were used to artificially inseminate does induced to ovulate normal or excess numbers of eggs. Fertility and subsequent embryonic development were examined. Frozen spermatozoa stored for 5 hr fertilized fewer oocytes than those stored for 5 days or longer. Fewer embryos were recovered on Day 6 than on Day 2. Blastocysts were smaller when spermatozoa were stored for 5 days, were frozen or were placed in superovulating does, but no statistically significant differences in the % of fetal survival were found in the groups of normally ovulating does. Embryonic wastage associated with storage of spermatozoa resulted from a reduced fertilization rate and/or increased embryonic mortality before implantation. 相似文献
995.
The migration inhibition in vitro induced by measles virus material on leukocytes from 17 patients with multiple sclerosis (MS) was compared with that of 8 patients with various other central nervous system diseases and that of 12 healthy blood donors. Significant differences could not be demonstrated. The results do not indicate that MS patients' leukocytes show an altered behaviour to measles virus material in the migration inhibition test. 相似文献
996.
HJ Harder 《Canadian Metallurgical Quarterly》1976,10(4):192-203
Corresponding to the fact that flammable anaesthetics are still very seldron in use the possibility of fires an explosions has diminished; the frequency of accidents caused by flammable colonic gases and by desinficients is about unchanged whilst a new kind can and dose occur: Fires and (occassional) explosions with "nonflammable" anaesthetic technics. A survey about 16 cases (including oxygen-fires) should be of interest for surgeons and intensive-care-people as well as for anaesthetists. 相似文献
997.
Measles virus-specific antibodies were isolated from sera, cerebrospinal fluids (CSF), and brain extracts of patients with subacute sclerosing panencephalitis (SSPE) and multiple sclerosis (MS) by absorption with measles antigens and subsequent acid elution of the antigen-antibody precipitates. Electrophoretically homogeneous measles antibodies were isolated from CSF or brain extracts in five patients with SSPE and in five out of seven patients with MS. Homogeneous IgG antibodies were also demonstrated in the sera from all SSPE patients and from three of the MS patients. The antibodies isolated from various control sera and from pooled CSF were electrophoretically heterogeneous. The results support the concept of a local synthesis in the nervous system of oligoclonal IgG antibodies to measles virus in all patients with SSPE and in some patients with MS. In SSPE, most or all oligoclonal IgG proteins of the CSF or brain carry measles antibody activities. In MS, only part of the oligoclonal IgG appears to be associated with measles antibody activity. 相似文献
998.
Renal adenocarcinoma is an infrequent tumor in children. The clinical and radiographic findings in 4 adolescents with such tumors are described. The surgical therapies of these patients and the possible role of adjunctive chemotherapy and radiotherapy are discussed. 相似文献
999.
The presence of an ulcer beneath callus on the diabetic foot has been a well-documented and common clinical finding. We have conducted a prospective study to examine whether callus can be used to predict plantar intrinsic neuropathic diabetic foot ulcer formation. Sixty-three diabetic patients (43 male, 25 Type 1), median age 62 years (IQ range 52, 67), median diabetes duration 17 years (IQ range 8,25) participated in the study. All had neuropathy and peak plantar foot pressures (measured using a dynamic optical pedobarograph) > or = 10 kg cm-2. Calluses and previous ulcers were documented and classified. All ulcers occurring prior to and during the study were recorded, re-examination was 15.4 (range 10-22) months from baseline. Seven ulcers (6 patients) occurred during the study. Pressures were higher in the ulcer than non-ulcer sub-group (p = 0.04) with a relative risk of developing an ulcer of 4.7 for an area of elevated plantar pressure. This compares with a relative risk of 11.0 for an ulcer developing under an area of callus, and a relative risk of 56.8 for an ulcer developing on a site of previous ulceration. This study confirms that a history of previous ulceration is the highest risk factor for ulceration and demonstrates, for the first time, that the presence of plantar callus is highly predictive of subsequent ulceration. Careful history taking and examination of the foot to detect the presence of callus require no special training or equipment and callus should be recognized as a 'high risk' factor for foot ulceration. 相似文献
1000.
The utilization of conducting emeraldine salt (PANI‐ES) and intrinsic leucoemeraldine polyaniline (PANI‐LEB) in the synthesis of DGEBA‐grafted PANI via anionic copolymerization is described. The structures of copolymers obtained were characterized by FTIR, 13C and 1H NMR. The extent of grafting was verified by THF Soxhlet (solvent extraction). The thermal properties of these new copolymers were described and their conductivities were reported. Results obtained indicated that the graft copolymer exhibited higher electrical and thermal conductivities than that of the blend counterpart. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献