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1.
Cotinine elimination from plasma, saliva, and urine was studied over 11 days in five subjects (three nonsmokers and two occasional smokers). Half-lives for cotinine averaged 16-19 hours in the different body fluids (range 10 to 27 hours between subjects). There was no tendency for the half-life in saliva to be longer than in plasma or urine. We conclude that choice of body fluid for cotinine assay in smoking studies should depend on practical rather than pharmacokinetic considerations.  相似文献   
2.
The objective was to demonstrate bioequivalence between s.c. and i.m. administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio 3:1). In two randomized, single-centre, cross-over studies, 18 healthy volunteers on each formulation were assigned to one of the two administration sequences. Subjects were given single doses of one of the above gonadotrophins after endogenous gonadotrophin production had first been suppressed using high-dose oral contraceptive. Subsequently, rate (Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax and AUC, analysis of variance (ANOVA) was performed on log-transformed data and for tmax ANOVA was performed on ranks. Intramuscular and s.c. injections of Humegon were bioequivalent with respect to the main pharmacokinetic parameters, being AUC and Cmax of FSH absorption. Intramuscular and s.c. injections of Normegon were bioequivalent with respect to the AUC of FSH and not bioequivalent with respect to the Cmax of FSH. For tmax of FSH as well as for most LH variables of both preparations, bioequivalence could not be proven due to the high intra- and interindividual variability and/or concentrations being close to the detection limit. Thus, the main pharmacokinetic FSH variables after i.m. and s.c. administration of Humegon and Normegon were bioequivalent.   相似文献   
3.
Blood nicotine, cotinine, and carboxyhaemoglobin (COHb) concentrations were measured in 392 smokers (255 women and 137 men) of "middle tar" (17-22 mg), "low to middle" (11-16 mg), and "low tar" (less than 11 mg) cigarettes. Since tar intake cannot yet be measured directly, we devised an index to estimate it based on the use of measured levels of an intake marker (eg, blood nicotine) and the ratio of the tar to marker yields of the cigarettes. This approach was validated by its ability to enhance the prediction of levels of one marker by use of another. In a practical test, using COHb and the CO/nicotine yield ratio of the cigarettes, the mean blood nicotine concentration of the low tar smokers was predicted to be 31.9 ng/ml compared with the measured mean of 31.8 ng/ml. Our main findings were that despite substantial compensatory increases in inhalation, the low tar smokers took in about 25% less tar, about 15% less nicotine, and about 10% less carbon monoxide than smokers of middle and low to middle tar cigarettes. These results indicate that low tar cigarettes of the type available in Britain since the late 1970s are likely to prove less harmful than other brands. Monitoring of smoke intakes could supplement epidemiological approaches and provide earlier evidence of whether changing cigarette designs lead to any significant dosage reduction that could affect the risk of disease.  相似文献   
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5.

Purpose

Endoscopic resection is a widely used technique for treatment of large colorectal adenomas, but few data are available including only lesions larger than ≥2 cm. The aim of this study is to evaluate the complication and recurrence rate after endoscopic resection of high-risk colorectal adenomas ≥3 cm in size.

Methods

Retrospective analysis of a prospectively maintained database of patients undergoing polypectomy of large colorectal polyps of ≥3 cm.

Results

In 341 patients, 360 colorectal adenomas with a mean size of 3.9 cm were resected endoscopically. In 25 patients, a complication including 22 delayed bleedings (6.5 %) and three perforations (0.9 %) occurred. Single-variate analysis showed an increasing risk of complications for larger adenomas (3.9 vs. 4.6 cm; p?≤?0.05). Two hundred twelve patients with 224 adenomas had undergone at least one documented follow-up endoscopy with a medium follow-up period of 16 months. In 95 resected lesions (42.4 %), a residual adenoma occurred in the first follow-up colonoscopy (n?=?88, 92.6 %) or a recurrent adenoma occurred after at least one negative follow-up colonoscopy (n?=?7, 7.4 %). In multivariate analysis, risk factors were lesion size, sessile growth pattern, and the performing endoscopist. The complication and recurrence rate correlated inversely between endoscopists.

Conclusions

The present study is the largest study showing complication and recurrence rates after colorectal polypectomy of advanced colorectal adenomas of ≥3 cm in size. Polyp size was identified as the most important risk factor for complications. For the first time, this study shows that the complication rate after colorectal polypectomy of large adenomas is correlated inversely with the residual and/or recurrence rate.
  相似文献   
6.
目的 分析延边地区建立肺结核归口转诊模式对肺结核病人的转诊到位率的影响,探讨提高转诊到位率的方法。方法 对全州8个县(市)医院、中医医院、中心卫生院、大型厂矿企事业单位职工医院的执法检查考核资料进行评价。结果 1.建立归口转诊模式前期转诊率为48.3%,转诊到位率为29.0%,后期转诊率为89.0%,转诊到位率为72.4%,有明显提高;2.前期年平均涂阳病人新登记率为13.36/10万,后期为17.86/10万,实施归口转诊模式前期与实施后期的指标有显著性差异(P<0.01)。结论 延边地区实施的肺结核病人归口转诊模式,对提高肺结核病的转诊到位率十分有效,应不断完善并深入推广。  相似文献   
7.
T Feyerabend  E Richter  M Ptok  W Bohndorf  A Ptok 《HNO》1989,37(7):295-298
Small glomus jugulare tumors can be operated on successfully. The intraoperative risk of bleeding may be reduced by preoperative irradiation or angiographic embolisation. Patients with advanced tumors (bone destruction, paralysis or cranial nerves and/or invasion of brain) are at high risk if they are operated on. In these cases radiotherapy is an effective alternative with a fairly low complication rate. Prerequisites for successful irradiation are assessment of treatment volume and treatment planning by CT, sophisticated stereotactic irradiation techniques, application of high energy photons and reliable immobilisation measures. Furthermore it is possible to deliver higher doses, leading to regression of the tumor and its symptoms. The technique is illustrated by two characteristic cases. Although irradiation alone can achieve tumor remission the long term prognosis remains doubtful.  相似文献   
8.
目的 探讨复治肺结核病人形成原因。方法 使用调查表的方法 ,对前来诊治的复治涂阳肺结核病人的首次诊疗 ,管理情况进行问卷调查。结果 综合医院仍然为大多数患者的首次诊疗单位 ,因此部分肺结核患者未能得到正确的诊断、治疗和化疗管理。导致 67.2 %病人“中断”或“间断”治疗 ;另外结核病健康教育宣传做得不够 ,60 .3 %的患者诊断前未接受过防痨宣教 ,3 4.5 %的患者接受初次化疗时仍未得到宣教。这些均在导致复治病人的产生中起了重要作用。结论 加大DOTS覆盖面 ,加强归口管理力度 ,做好防治结核病教育工作是防止复治肺结核病人产生的重要环节。  相似文献   
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10.
A rapid method is described for the simultaneous measurement of nicotine and cotinine in biological fluids using capillary column gas-liquid chromatography. Using 100 microliters sample volume the lower limit of detection for both nicotine and cotinine was 100 pg mL-1, allowing the method to be used for the measurement of these compounds in both smokers and non-smokers. The extraction time is 3 min per sample, and by using multi-pipetting and vortexing systems 250 samples can be extracted per day. The average coefficient of variation over the nicotine range 1.0 to 100 ng mL-1 was 3.9% and for cotinine over the range 1.0 to 1000 ng mL-1 was 2.2%. Saliva cotinine concentrations were quantitatively related to passive exposure to parental smoking in a population study of 1118 non-smoking schoolchildren.  相似文献   
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