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81.
本试验探讨了华南双季稻区利用亚种同杂种优势的特点和问题,结果表明:当前,两系亚种问杂种一代主要存在的问题是结实率低和谷草比低;籼粳交杂种易受环境条件的影响;每穗实粒数和单株有效穗数是决定单株产量的重要因子;每穗实粒数增加的关键在于结实率的提高,本文还就提高结实率和谷草比等问题提出了意见。 相似文献
82.
根据嗜肺军团菌基因组DNA的种特异性DNA片段序列,合成一对引物进行聚合酶链反应(PCR)。经琼脂糖凝胶电泳、EB染色结果表明,一条870bp的核苷酸区带为嗜肺军团菌1~14血清型菌株所共有。PCR检测水中军团菌,其敏感性为350cfu/ml,而用同位素标记探针、斑点杂交法检测,其敏感性为43cfu/ml。PCR检测人工感染嗜肺军团菌的豚鼠组织标本,阳性率为83.3%,而细菌分离培养的阳性率仅为26.6%。在现场调查中,用PCR法初步验证了一起由Lp10引起的军团菌病爆发。上述结果表明,PCR法能快速、敏感、特异性检测嗜肺军团菌感染。 相似文献
83.
Peter Reimer Sanjay Saini Ken K. Kwong Mark S. Cohen Ralph Weissleder Thomas J. Brady 《Journal of magnetic resonance imaging : JMRI》1994,4(3):331-335
To develop guidelines for clinical magnetic resonance imaging of the liver, the authors undertook an animal study to investigate the effect of dose and pulse sequence on liver signal intensity in gadopentetate dimeglumine—enhanced echo-planar imaging. Serial imaging of the liver was performed in anesthetized rats after intravenous administration of five different doses (0.01, 0.05, 0.1, 0.2, and 0.5 mmol/kg) of contrast agent, with six different pulse sequences. The results show that gadopentetate dimeglumine—enhanced echo-planar images obtained during the perfusion phase can yield either positive (due to increased T1 relaxation rates) or negative (due to susceptibility-induced increased T2 relaxation rates) liver enhancement depending on choice of pulse sequence and dose. At the current clinically recommended dose of 0.1 mmol/kg, maximal liver signal enhancement was seen with a T1-weighted inversion-recovery sequence, while maximal liver signal diminution was seen with a T2*-weighted gradient-echo sequence. The authors conclude that gadopentetate dimeglumine—enhanced echo-planar imaging can provide T1, T2, and T2* contrast that may be exploited for both lesion detection and lesion characterization. 相似文献
84.
85.
Masayuki Imamura Yutaka Shimada Yuhji Kanda Manabu Fukumoto Ken Yanagibashi Tokiharu Miyahara Takayoshi Tobe 《Surgery today》1992,22(5):409-415
In order to decrease the perioperative complications by preoperative cisplatin chemotherapy, the preoperative single administration of cisplatin (30 mg/m2) was performed weekly from one to six times in 36 consecutive patients with esophageal cancer classified as higher than Stage II. The survival curve of 17 patients in Stage III was significantly better (P<0.05) than that of patients who had been treated without preoperative cisplatin treatment. In 3 of the 12 patients who had locally invasive cancer, either the main tumors or the metastatic lymph nodes, which had invaded the trachea or the left main bronchus, sufficiently receded, so that a curative esophagectomy became possible; 2 of them have survived over 33 months while 1 died of pneumonia 33 months after surgery. The number of perioperative complications was minimal, and thus, we consider that the postoperative use of cisplatin and fluorouracil is indicated in patients in whom a histological response is noted in the resected specimens.This work was partially supported by Grant No. 02454315 from the Japanese Ministry of Education 相似文献
86.
87.
Ken Kodama Osamu Doi Masahiko Higashiyama Hideoki Yokouchi Keiko Kuriyama 《Surgery today》1997,27(12):1123-1130
Between 1969 and 1995, 180 patients underwent complete resection of lung metastases during initial thoracotomy at our institute,
involving the resection of 917 pulmonary nodules at 202 thoracotomy procedures. The overall postmetastasectomy 5- and 10-year
survival rates were 46% and 30%, respectively. Of 111 patients who underwent segmentectomy and/or local excision, 57 had multiple
metastases, 39 of whom were treated by Nd:YAG laser after 1986, and 18 by conventional procedures before 1985. The average
number of tumors resected per patient treated with the Nd:YAG laser was significantly greater than that of those treated with
conventional procedures. However, the survival curve of the laser-treated group was better than that of the laser-nontreated
group. Moreover, slightly better survival was achieved in patients operated on after 1992 compared with those operated on
before 1991. We conclude that the laser technique may be warranted to afford complete resection of metastases and adequate
pulmonary reservation in combination with a selected approach for thoracotomy under the exact detection of tumor localization
using the most recent high-quality computed tomography (CT) scan. Furthermore, a one-stage operation to control synchronous
intra- and extrapulmonary malignamcies may become a possible option in combination with selective adjunctive therapy. 相似文献
88.
本文运用模糊数学原理,对东台市1993年7月份市面上的全脂乳粉抽查监测结果进行卫生质量综合评价,结果令人满意,从而为乳粉卫生质量评比建立了客观有效的评价模型。 相似文献
89.
Measurement of patient satisfaction is an essential part of health outcome assessment. The purpose of this study is (a) to compare the stability of an aggregate summary measure and two separate summary measures of patient satisfaction; and, (b) to examine causal effects between two separate summary measures at two points in time. Data were collected from 1,451 Medicare HMO beneficiaries. In conclusion, (a) separate summary measures are recommended for constructing the measure of patient satisfaction and (b) moderate causal relationships and cross-lagged effects between the patient satisfaction measures of qualify of care and access to care were found. 相似文献
90.
消化道恶性肿瘤确诊初期患者社会支持与生命质量的调查 总被引:6,自引:1,他引:5
目的 调查消化道恶性肿瘤确诊初期的患者半年中的社会支持和生命质量变化。方法 采用社会支持评定量表和CARES-SF对146名患者的社会支持和生命质量进行为期半年的追踪调查。结果 消化道恶性肿瘤确诊初期患者的生命质量为中等,其中婚姻关系维度、性关系维度得分半年后下降。患者所获得的社会支持最多的是情感支持,其次是实际支持,信息支持为第三位。情感支持大多来源于家庭成员,信息支持大多来源于医务人员。患者大多很少参与社交活动。在半年中情感支持、实际支持、信息支持的变化模式不一。诊断初期的患者不能有效地利用社会支持。结论 应对确诊初期患者加强咨询,以充分识别和利用社会资源。应持续评估患者的生命质量和社会支持,并制订干预方案,提高消化道恶性肿瘤确诊初期患者的社会支持程度,最终提高其生命质量。 相似文献