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131.
本文报道pH指示剂吸收度比值法测定盐酸乙胺丁醇的含量。该法采用指示剂为0.05%茜素黄R,测定波长374nm和500nm;标准液为0.1mol/L NaOH;仪器为WFZ-800D_2型分光光度计。测得三批盐酸乙胺丁醇的含量分别为99.5±0.04%,99.4±0.05%和99.6±0.03%.同时与药典法比较,结果一致。  相似文献   
132.
Background : A patient with a solitary pulmonary metastasis who had breast cancer in the past may benefit from pulmonary resection. Methods : Between 1984 and 1996, 17 patients underwent metastatectomy for metastatic breast cancer. There were 15 females and two males whose average age was 59 (range: 40–74 years). The median tumour-free interval after the primary breast-cancer operation was 5.1 years (range: 8 months-18.2 years). Sixteen patients had complete resections, which included six lobectomies and 10 lesser resections. Results : The postoperative mortality was nil and the morbidity rate was 6%. Follow-up was complete in all patients. Recurrent disease developed in four patients and two patients died of their disease. The 5-year survival was 62%. Conclusion : An aggressive surgical approach is warranted in patients with isolated resectable pulmonary metastases from breast cancer.  相似文献   
133.
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   
134.
对沈阳市某幼儿园99例3~6岁锌缺乏儿童的营养调查和生物样品(血液、尿液和毛发)的分析发现:同对照组儿童相比,锌缺乏儿童除Fe、维生素A外,其他主要营养素的摄入明显不足;缺锌儿童的发锌、RBC锌水平、血清ALP活性、尿锌/尿肌酐比值均明显低于对照组。经补锌治疗后血浆锌水平、血清ALP活性、尿锌/尿肌酐比值显著升高。应用临床诊断实验的评价方法分析发现结合血浆锌水平,联合使用发锌,血清ALP和尿锌/尿肌酐比值3项指标可以准确判断儿童边缘性锌缺乏,这时并联的灵敏度为96.18%,串联的特异度可高达到100%(血清ALP活性<104IU/L,同时发锌含量<110ppm.尿锌/尿肌酐比值<0.3μg/g)。  相似文献   
135.
Studies have shown that both food deprivation and response cost have important influences on the magnitude of self-administration of a wide variety of psychoactive drugs. In an attempt to extend these findings to the smoked route of drug self-administration, the effects of food allotment and fixed-ratio (FR) value were evaluated in four male rhesus monkeys trained to smoke cocaine base. In the first phase of the experiment, monkeys were trained to self-administer smoked cocaine base under a chained progressive-ratio (PR), fixed-ratio (FR) schedule during daily experimental sessions. Monkeys were required to make 20 lever-press responses and then five inhalations on a smoking spout to obtain the first smoke delivery. The lever ratio then increased to 60, 140, 300, 620, 1260, 2540, and 4940 for each successive smoke delivery. The initial lever ratio value was reset to 20 at the beginning of each daily session. The body weights of three monkeys were determined under free-feeding conditions. Monkeys were then restricted to 100 g food and, when body weights had stabilized, the daily food allotment was increased to 150 g, approximately 210 g, or greater than 400 g (satiation). As the daily food allotment and body weight increased, the mean number of smoke deliveries decreased in two of three monkeys. In the second phase of the experiment, three monkeys were maintained under either food-satiated or food-restricted conditions. Body weights were maintained at approximately 90% of their free-feeding weights under food-restricted conditions. The cost of the drug (lever FR value) was constant within each experimental session, but was increased after 3 consecutive days of stable responding. Fixed-ratio values were increased from 128 to 256, 512, 1024, and 2048. Monkeys were required to complete the lever FR value and then to make five inhalations on the smoking spout to gain access to 1.0 mg/kg per delivery cocaine base. The mean number of smoke deliveries increased at FR 256, 512, and 1024 when monkeys were food-restricted as opposed to food-satiated. Correspondingly, the mean number of responses increased under food-restricted conditions. Responding continued to increase over a wider range of FR values, and the peak number of responses was higher under food-restricted, as opposed to food-satiated conditions. These results, using the smoking route of administration, are consistent with the hypothesis that food deprivation increases the self-administration of reinforcing drugs.  相似文献   
136.
空洞型肺转移瘤的CT表现及与原发灶病理类型的关系   总被引:13,自引:1,他引:12  
目的:探讨空洞型肺转移瘤的C表现及其与原发灶病理类型的关系。资料与方法:报告空洞型肺转移瘤40例131枚,分析其CT表现并与原发灶病理类型进行对比。结果:全部空洞瘤灶均与肺多发实性结节共存。共有泡样空洞41枚,不规则空洞33枚,囊样空洞26枚,小环形空洞31枚。壁厚度均匀者61枚,不均匀者70枚。瘤灶直径<15mm者44枚,15-25mm者66枚,25-40mm者17枚,>40mm者4枚。洞壁厚度<4mm者69枚,4-15mm者44枚,>15mm者18枚。空洞型瘤灶多见于腺瘤(22例)与鳞癌(13例),二者在CT表现上各有一定特征。空洞型瘤灶的发生与其在肺内的部位无关。结论:空洞型肺转移瘤的CT表现具有一定特点,并与原发灶病理类型有关。  相似文献   
137.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义   总被引:1,自引:1,他引:0  
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。  相似文献   
138.
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c…  相似文献   
139.
香烟烟雾吸入对大鼠局灶性脑缺血后梗死灶的影响   总被引:1,自引:1,他引:0  
目的 观察香烟烟雾吸入对大鼠局灶性脑缺血后梗死灶的影响,探讨其机制。方法 建立吸烟大鼠模型。用TTC染色法测定梗死灶体积,检测大鼠局灶性脑缺血后神经功能缺陷评分及梗死灶体积占同侧半球百分比。结果 除戒烟组外各吸烟组大鼠神经功能缺陷评分及梗死灶体积与对照组相比显著增加,吸烟4周、8周及12周依次增加。戒烟组神经功能评分及梗死体积明显低于吸烟4周组,与对照组无显著差别。结论 吸烟可加重大鼠局灶性脑缺血后脑组织损害,且随着吸烟时间增加而加重,戒烟可使这种脑损害得到一定程度的恢复。  相似文献   
140.
Investigators have tried to identify a level of seric specific immunoglobulin E (IgE) that had a sufficient predictive value to diagnose a food allergy without having will resort to the food challenge. To search in literature, all the studies that have estimated the possibility to identify a level of seric specific cow milk IgE with a positive predictive value (PPV) of 95% for the first diagnosis of cow's milk allergy (CMA) in pediatric age. We have identified six studies, nearly all studies suffer from relevant methodological bias. Proposed cut-off are all different. The studied pediatric populations were highly selected. Also neglecting the methodological bias of the studies and the great difference of value between the proposed cut-off, it always remains to consider that the pre-test probability of having a CMA between the children enrolled in the six studies included in this review is particularly high. The likelihood ratio helps to transfer the results of a study on a diagnostic test just to our population, and it is more realistic rather than to entrust itself to the PPV or the negative predictive value, that are much influenced from the prevalence of the disease in the studied population.  相似文献   
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