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991.
目的为了寻求一种实际工作中准确实用的便潜血检测方法。方法使用化学法及免疫法对100例患者进行潜血实验检测。结果化学法假阳性率为12%,免疫法假阴性率为9%。结论胶体金单克隆抗体。免疫法特异性、灵敏度高,抗干扰性强,但可出现假阴性结果化学法易出现假阳性结果。在临床工作中两种方法结合使用可获得准确的实验结果,有较好的临床应用价值。 相似文献
992.
目的 为了探讨男性不育症患者的发病机理。方法通过检测20例对照组(生育组)与140例观察组(不育组)精浆中的果糖、锌、酸性磷酸酶、中性α-葡糖苷酶、弹性硬蛋白酶、LDH—X、项体酶,综合分析两组精浆中的化学成分变化。结果不育症组精浆中的果糖、锌、中性α-葡糖苷酶、顶体酶每次射精含量都显著低于生育组(P≤0.01);酸性磷酸酶、LDH—X每次射精含量稍低于生育组,但无统计学意义(P>0.01);而不育组弹性硬蛋白酶浓度明显高于生育组(P〈0.01)。结论精浆中的果糖、锌、酸性磷酸酶、中性α-葡糖苷酶、弹性硬蛋白酶、LDH—X、项体酶浓度可以用来综合评估男性患者的生育能力。 相似文献
993.
Purpose Rectal instillation of 4 percent formalin solution has been described as a successful treatment for hemorrhagic radiation
proctitis recalcitrant to medical treatment. We present our experience with a new method of treatment involving the topical
application of 10 percent buffered formalin, which is well tolerated and suitable for office use.
Methods Patients with marked or refractory rectal bleeding and clinical features consistent with radiation proctitis were reviewed.
Treatment involved direct application of a 10 percent buffered formalin solution to the affected mucosa using a 16-inch cotton
tip applicator applied through a proctoscope in the office setting.
Results A total of 100 patients with a mean age of 75 (range, 49–91) years were followed for 18 (range, 1–79) months. The interval
from radiation exposure to formalin treatment was 21 months. Overall, 93 percent of patients had cessation of bleeding after
an average of 3.5 formalin applications at two-week to four-week intervals. Patients with severe (Grade 3) proctitis and those
taking aspirin required an average of 1.5 additional treatments. A total of eight patients rebled at a mean of 24 months from
treatment; however, all responded to further applications of formalin. Three patients complained of anal pain and one experienced
dizziness postprocedure for a complication rate of 1.1 percent.
Conclusions We present a simple, cost-effective, and well-tolerated method of controlling hemorrhagic radiation proctitis. It is performed
by using materials readily available in the office of a colon and rectal surgeon, eliminating the need for bowel preparation,
anesthesia, or a surgical suite.
Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, New Orleans, Louisiana, June 21 to
26, 2003. 相似文献
994.
Zhuoma Dawa Yang Bai Yan Zhou Suolang Gesang Ping A Lisheng Ding 《Journal of natural medicines》2009,63(3):327-330
The chemical constituents of the traditional Tibetan medicine of Saussurea medusa Maxim. (Compositae) were investigated and a new flavonoid glucoside, together with 14 known compounds, was isolated. The
structure of the new compound was established as 6″-O-crotonoylhomoplantaginin by using one- and two-dimensional nuclear magnetic resonance spectroscopy and mass spectrometry
analyses. 相似文献
995.
Optimized conditions for the extraction of secondary volatile metabolites in Angelica roots by accelerated solvent extraction 总被引:1,自引:0,他引:1
Cho SK Abd El-Aty AM Choi JH Kim MR Shim JH 《Journal of pharmaceutical and biomedical analysis》2007,44(5):1154-1158
Accelerated solvent extraction (ASE) of three common Angelica species found in Asia: Angelica sinensis (Oliv.) Diels from China, Angelica acutiloba (Sieb. et Zucc.) Kitagawa from Japan, and Angelica gigas Nakai from Korea was investigated. Preliminary experiments, including the selection of the solvent, extraction time, pressure, static cycle and time were investigated to optimize experimental parameters. Kováts indices and mass spectra were used to identify the components in the various fractions. These were then confirmed using gas chromatography–mass spectrometry (GC–MS). A total of 18 compounds were identified, with qualitative differences and similarities observed among the cultivars. From the 18 compounds found in the ASE extract of danggui cultivars, the major components were decursin, decursinol angelate (A. gigas); butylidene dihydrophthalide, 4-hydroxy-4-methyl-2-pentanone (A. sinensis); and 9,12-octadecanoic acid in Angelica acutiloba. The optimum ASE operating conditions were n-hexane as extraction solvent, extraction temperature and pressure of 80 °C and 1500 atm, respectively, static cycle of 2 min, and static time of 10 min. Under these conditions, the percentages of main analytes were increased. 相似文献
996.
Colocating buprenorphine with methadone maintenance and outpatient chemical dependency services 总被引:1,自引:0,他引:1
Whitley SD Kunins HV Arnsten JH Gourevitch MN 《Journal of substance abuse treatment》2007,33(1):85-90
Buprenorphine may be used to treat opioid dependence in office-based settings, but treatment models are needed to ensure access to psychosocial services needed by many patients. We describe a novel buprenorphine treatment program colocated with methadone maintenance and outpatient chemical dependency services. We conducted a retrospective chart review of the first 40 consecutive patients initiating buprenorphine treatment in this program to determine characteristics associated with treatment retention. Exclusion criteria were current alcohol or benzodiazepine dependence. Secondary drug users and patients who were psychiatrically or medically ill were included. At 6 months, 60% (n = 24) were retained, 13% (n = 5) tested positive for opiates, and 25% (n = 10) tested positive for secondary substances. Patients who were older (odds ratio [OR] per year of age = 1.1, confidence interval [CI] = 1.0-1.2) and those who were employed (OR = 9.8, CI = 1.8-53.1) were more likely to remain in treatment, but other variables were not associated with retention. Our experience demonstrates that buprenorphine can be successfully integrated into outpatient substance abuse treatment. 相似文献
997.
Sams R Wolf DC Ramasamy S Ohanian E Chen J Lowit A 《Toxicology and applied pharmacology》2007,222(3):245-251
The chronic exposure of humans through consumption of high levels of inorganic arsenic (iAs)-contaminated drinking water is associated with skin lesions, peripheral vascular disease, hypertension, and cancers. Additionally, humans are exposed to organic arsenicals when used as pesticides and herbicides (e.g., monomethylarsonic acid, dimethylarsinic acid (DMA(V)) also known as cacodylic acid). Extensive research has been conducted to characterize the adverse health effects that result from exposure to iAs and its metabolites to describe the biological pathway(s) that lead to adverse health effects. To further this effort, on May 31, 2006, the United States Environmental Protection Agency (USEPA) sponsored a meeting entitled "Workshop on Arsenic Research and Risk Assessment". The invited participants from government agencies, academia, independent research organizations and consultants were asked to present their current research. The overall focus of these research efforts has been to determine the potential human health risks due to environmental exposures to arsenicals. Pursuant in these efforts is the elucidation of a mode of action for arsenicals. This paper provides a brief overview of the workshop goals, regulatory context for arsenical research, mode of action (MOA) analysis in human health risk assessment, and the application of MOA analysis for iAs and DMA(V). Subsequent papers within this issue will present the research discussed at the workshop, ensuing discussions, and conclusions of the workshop. 相似文献
998.
Teuschler LK 《Toxicology and applied pharmacology》2007,223(2):139-147
The most commonly used chemical mixtures risk assessment methods involve simple notions of additivity and toxicological similarity. Newer methods are emerging in response to the complexities of chemical mixture exposures and effects. Factors based on both science and policy drive decisions regarding whether to conduct a chemical mixtures risk assessment and, if so, which methods to employ. Scientific considerations are based on positive evidence of joint toxic action, elevated human exposure conditions or the potential for significant impacts on human health. Policy issues include legislative drivers that may mandate action even though adequate toxicity data on a specific mixture may not be available and risk assessment goals that impact the choice of risk assessment method to obtain the amount of health protection desired. This paper discusses three important concepts used to choose among available approaches for conducting a chemical mixtures risk assessment: (1) additive joint toxic action of mixture components; (2) toxicological interactions of mixture components; and (3) chemical composition of complex mixtures. It is proposed that scientific support for basic assumptions used in chemical mixtures risk assessment should be developed by expert panels, risk assessment methods experts, and laboratory toxicologists. This is imperative to further develop and refine quantitative methods and provide guidance on their appropriate applications. Risk assessors need scientific support for chemical mixtures risk assessment methods in the form of toxicological data on joint toxic action for high priority mixtures, statistical methods for analyzing dose-response for mixtures, and toxicological and statistical criteria for determining sufficient similarity of complex mixtures. 相似文献
999.
Intake of chemical contaminants through fish and seafood consumption by children of Catalonia, Spain: health risks. 总被引:4,自引:1,他引:3
Roser Martí-Cid Ana Bocio Juan M Llobet José L Domingo 《Food and chemical toxicology》2007,45(10):1968-1974
The intake of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated diphenylethers (PBDEs), polychlorinated diphenylethers (PCDEs), hexachlorobenzene, and polycyclic aromatic hydrocarbons through fish and seafood consumption by children of Catalonia, Spain, was assessed. In 2005, samples of the 14 most consumed marine species in Catalonia were randomly acquired in various cities of the country. Analysis of the above chemical contaminants were determined according to the appropriate analytical techniques and the daily intakes were estimated. For most pollutants, intake was higher in boys than in girls. Average exposure of children to contaminants through fish and seafood consumption did not exceed the respective tolerable daily intake of those pollutants for which it has been already established (metals, PCDD/Fs plus dioxin-like PCBs, HCB, and PAHs). In relation to body weight, intake by children of most contaminants was higher than that found for other age groups of the general population of Catalonia. 相似文献
1000.
In recent years, and based on the importance of fish as a part of a healthy diet, there has been a notable promotion of fish and seafood consumption. However, a number of recent studies have shown that fish may be a potential source of exposure to chemical pollutants, some of them with well known adverse effects on human health. Recently, we determined in 14 edible marine species the concentrations of eicosapentaenoic acid (EPA) and docosohexaenoic acid (DHA), as well as those of a number of chemical contaminants: Cd, Hg, Pb, polychlorinated dibenzo-p-dioxins and furans, polychlorinated biphenyls, hexachlorobenzene, polycyclic aromatic hydrocarbons, polychlorinated naphthalenes, polybrominated diphenylethers and polychlorinated diphenylethers. To quantitative establish the intake of these pollutants (risks) versus that of EPA + DHA (benefits), we designed a simple computer program, RIBEPEIX. The concentrations of EPA, DHA, and the chemical pollutants were introduced into the program. We here present how RIBEPEIX may be used as an easy tool to optimize fish consumption: most suitable species, frequency of consumption, and size of meals. RIBEPEIX can be useful not only for professionals (cardiologists, general physicians, nutritionists, toxicologists, etc.), but also for the general population. It is available at: http://www.fmcs.urv.cat/portada/ribepeix/. 相似文献