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991.
In a prospective randomized trial, 361 male patients with histologically proven adenocarcinoma of the rectum, judged preoperatively to require abdominoperineal resection (APR), were treated by surgery alone or were given 3,150 rads of preoperative radiotherapy. Surgical resection was done on 320 patients, 262 having "curative" APR. Only moderate symptoms from radiotherapy were noted and postoperative complications and 30-day mortality were similar in both groups. Five-year survival for curative APR was the same in both groups (50% for both treated and control patients). The incidence of positive lymph nodes in the resected specimens was 35% in treated and 41% in controls. In the first preoperative radiotherapy trial conducted by the group, 5-year survival in patients undergoing "curative" APR was 47% in treated versus 34% in control groups. Additionally, the difference in positive lymph nodes in the resected specimens was substantially greater in the first trial (26% in treated versus 44% in controls).  相似文献   
992.
3'-Radiohalogenated (36Cl, 82Br and 123I) "arabino" pyrimidine nucleosides were evaluated as potential tumor diagnostic agents in tumor bearing animals. No preferential tissue uptake was observed. The compounds were excreted mainly unchanged in the urine. The 3'-[36Cl]- and 3'-[82Br]-3'-deoxyarabino nucleosides exhibited biliary uptake. The low uptake of injected radioactivity by the tumor was probably due to the combined effects of the lack of a C-3' hydroxyl group in the "ribo" configuration, the presence of a halogen, the structural rigidity imposed by the presence of a halogen and the short biological half-lives of the compounds.  相似文献   
993.
994.
Single doses of procarbazine (MIH) were injected IP at 0, 50, 100, 200, and 400 mg/kg body weight to CD-1 male mice. Activities of hyaluronidase, lactate dehydrogenase isoenzyme-X, and the dehydrogenases of sorbitol, -glycerophosphate, glucose-6-phosphate, malate, isocitrate, and glyceraldehyde-3-phosphate in the testes of the mice were determined and correlated with changes in spermatogenic cell types in seminiferous tubules. All enzyme activities were higher than controls or remained unchanged on days 10–20 after drug treatment. Activities of hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X decreased significantly to below normal levels on day 30 after drug treatment for all doses, whereas those of the other five dehydrogenases remained significantly higher than controls. All enzyme activities approached control levels with the concomitant recovery of spermatogenesis by day 60 after drug treatment. Histological examination of seminiferous tubules revealed that premeiotic spermatocytes were significantly reduced on days 10–20 but reappeared on day 30 after MIH treatment (400 mg/kg). The postmeiotic spermatogenic cells were unaffected at the time of MIH treatment, but had disappeared completely on day 30 after drug treatment. MIH, at the highest dosage, selectively destroyed spermatogonia and premeiotic spermatocytes; however spermatozoa and elongated spermatides were unaffected. This study demonstrated that the cytotoxic effect of MIH on spermatogenesis could be evaluated via changes in testicular enzyme activities. The present studies demonstrated that hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X could serve as useful biochemical markers for assessing testicular toxicity induced by drugs and chemicals.  相似文献   
995.
A study was carried out to determine the health effects of rice husk dust in Malaysian rice millers. The study population consisted of 122 male Malay workers from three rice mills, with 42 controls of similar age, sex, ethnic group, and agricultural work background. Interviews using standardised questionnaires, physical examination, total and differential white cell counts, chest radiographs, and lung function tests were performed on each of the millers and the controls. Environmental dust monitoring was also carried out in the three rice mills. Clinical, haematological, and radiological findings suggest that a distinct clinical syndrome seems to be associated with exposure to rice husk dust. The manifestations of this "rice millers' syndrome" include acute and chronic irritant effects affecting the eyes, skin, and upper respiratory tract; allergic responses such as nasal catarrh, tightness of chest, asthma, and eosinophilia; and radiological opacities in the chest, probably representing early silicosis or extrinsic allergic alveolitis.  相似文献   
996.
A simple geometrical method of measuring anterior chamber dimensions   总被引:1,自引:0,他引:1  
Equations are described to derive the true anterior chamber dimensions of an eye from a photograph of its optical section. If the surface of the eye is assumed to be spherical, the three-dimensional coordinates of rays emanating from the anterior chamber to a camera can be transformed to two-dimensional coordinates on a plane, which contains rays both inside and outside of the "eye." The actual dimensions of the anterior chamber then were computed on the basis of the ray tracing over the entire corneal surface. The accuracy of the equations was checked using scales prepared from photographs of curvilinear grids inside an artificial anterior chamber. The advantages of this method are that the true anterior chamber dimensions can be measured in an eye of any corneal curvature and with any type of slit-lamp camera. It appears sufficiently accurate and convenient to be used for clinical and animal studies.  相似文献   
997.
The effects of plasma concentration and pH on the steady-state volume of distribution, Vss,of methotrexate (MTX) were studied in five conditioned male beagle-mongrel dogs. Steady-state plasma MTX concentrations of approximately 1, 20, and 100g/ml were targeted for by i.v. bolus doses followed by i.v. infusions. An isotonic solution of sodium bicarbonate or ammonium chloride was simultaneously infused for the purpose of inducing plasma pH change, while the infusion of an isotonic solution of sodium chloride served as a control. Plasma and urine concentrations of MTX were quantitated by a sensitive high-performance liquid chromatographic method, and the Vss of MTX was estimated by a recently reported physiologically based method of Chiou and Lam. Statistically significant (p<0.05) concentration and plasma pHdependent Vss of MTX were observed. Concentration dependence of Vss was noted in sodium chloride and ammonium chloride infused dogs, but not in bicarbonate treated dogs. There was an average 50.0 and 44.8% increase in Vss at 1 g/ ml relative to the two higher concentrations (20 and 100 g/ ml) for dogs treated with ammonium and sodium chloride, respectively. However, Vss of MTX at the targeted concentrations of 20 and 100 g/ml was relatively constant. Plasma pHdependence of Vss was observed only at the plasma concentration of 1 g/ml, and on the average, ammonium chloride and sodium chloride treatments resulted in 50.0 and 31.3% higher Vss,respectively, when compared with the bicarbonate treatment. These phenomena appear to be adequately explained by the reported tissue uptake kinetics of MTX.This research was supported in part by a grant from the National Cancer Institute, CA-29754.Abstracted from a dissertation submitted in 1984 by Chung Y. Lui to the Graduate College, University of Illinois at Chicago, in partial fulfillment of Doctor of Philosophy Degree requirements.  相似文献   
998.
目的明确颅脑肿瘤术后患者发生静脉血栓栓塞症(VTE)的危险因素。方法检索中国知网、万方、维普、中国生物医学文献、PubMed、The Cochrane Library、Web of Science、EMbase等数据库建库至2021年11月1日颅脑肿瘤术VTE危险因素的队列研究或病例对照研究。由两名研究人员独立进行文献筛选、资料提取以及文献质量评价。使用RevMan 5.4软件对纳入文献进行Meta分析。结果共纳入14篇文献,合计样本量40 552例,发生VTE1 801例。Meta分析结果显示,年龄>45岁、术前D-二聚体升高、肥胖、女性、术前日常生活活动能力处于依赖状态、术前呼吸机依赖、术前曾患脓毒血症、高级神经胶质瘤、手术时间>3.05 h、术后D-二聚体升高、术后下肢运动功能障碍、术后卧床不起、术后并发尿路感染为颅脑肿瘤术后患者发生VTE的危险因素。结论颅脑肿瘤术后VTE发生与多种因素有关。建议构建颅脑肿瘤术后VTE风险预测模型,关注高风险人群,落实规范化静脉血栓风险评估,注重血栓评估过程管控。  相似文献   
999.
Relational continuity of care (COC) is becoming an important concept related to improving healthcare quality, reducing medical costs and increasing patient satisfaction with primary care. While community pharmacy (CP) has a considerable role in primary care, there are few reports dedicated to the role of relational COC in CP. This study reviewed the existing evidence of relational COC in CP and its effect on patients. PubMed, Embase, CINAHL, Cochrane Library CENTRAL and Google Scholar were used to search for relevant studies from the date of database inception through to January 2021, which were appraised according to eligibility criteria. There were no limitations on the primary outcome or language. Case reports and studies without control groups were excluded. The Newcastle–Ottawa quality assessment scale was used to assess the quality of the studies. Database searches identified 13 records. Relational COC measures in the included studies were grouped in three kinds; pharmacy-visiting pattern, Continuity of Care Index and loyalty. The assessed outcomes were medication adherence behaviour (e.g., the proportion of days covered, medication possession ratio), adverse drug reactions, potentially inappropriate drug prescribing and clinical outcomes. The odds of patients adhering to their medication regimen were about 1.1~2.5 times higher among those who consistently visited a single pharmacy compared to patients visiting multiple pharmacies. Additionally, the care provision with a high level of relational continuity could lower inappropriate drug use by 21~32 per cent and the use of other costly services by 12~29 per cent. This study suggests that a high degree of relational COC in CP could improve safe use of medications among patients. Future research is needed to employ more rigorous methods to reduce heterogeneity and to measure effects on clinical outcomes.  相似文献   
1000.
Journal of Public Health - The present study aimed to examine the effects of primary social factors on the smoking behaviors according to the smoking stages—initiation and...  相似文献   
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