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991.
In the operative treatment of appendicitis the so called negative appendectomy is an important issue because of its increased morbidity. From the hypothesis that the intestinal diamine oxidase activity is a suitable marker of mucosal integrity, the distribution pattern of the enzyme in appendices histologically classified as inflamed or not inflamed was studied. Histologically apparent inflammation of the appendix was connected with a significant reduction of diamine oxidase activity. The determination of this enzymic activity may be a simple and sensitive test for mucosal inflammation of the appendix even at a very early state. This could reduce the rate of negative appendectomies and influence thereby risk-cost-benefit calculations.  相似文献   
992.
Recent reports have shown that alpha-naphthoflavone (alpha-NF) in vivo enhances the sister chromatid exchange (SCE) frequency in lymphocytes from human populations exposed to cigarette smoke or polychlorinated biphenyls and dibenzofurans. In this study, female Sprague-Dawley rats (9-11 weeks old) were administered a single oral dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and killed 6 days after treatment. Blood cultures were established with or without alpha-NF. The baseline and alpha-NF-induced SCE frequencies were assessed in lymphocytes after a 72-hr culture period. No effect on the SCE baseline frequency (cultures without alpha-NF) was detected in rats exposed to 0-30 micrograms TCDD/kg. However, the SCE frequencies from cultures incubated in the presence of alpha-NF were significantly higher in lymphocytes from rats treated with TCDD. Moreover, delta SCE values (SCE alpha-NF minus SCE baseline) were significantly higher in lymphocytes from rats treated with TCDD than in controls. A dose-dependent increase in delta SCE values was observed between 0 and 3 micrograms TCDD/kg, followed by a plateau at higher doses. This induction pattern closely resembled the induction of the liver microsomal aryl hydrocarbon hydroxylase activity by TCDD. In contrast to TCDD, phenobarbital treatment of rats (75 mg/kg/day) had no effect on alpha-NF-induced SCE frequencies in lymphocytes. Liver microsomes from TCDD-treated rats metabolized alpha-NF at a rate much faster than that of control microsomes. These studies indicate that TCDD-exposed rats provide a useful model to investigate the mechanism of enhanced in vitro induction of SCE frequency in lymphocytes from humans exposed to toxic halogenated aromatics or cigarette smoke.  相似文献   
993.
994.
A new technology is developed for the production of activated charcoal (AU-L) tablets from cotton lignin, a readily available local raw plant material. The physicochemical and technological properties of the parent substance (powder) have been studied and the optimum composition of tablets has been determined. The best technological characteristics of both the initial mass and the ready-to-use tablets are achieved for the composition involving a 3% methyl cellulose gel as a binding component and microcrystalline cellulose as a filler. The qualitative characteristics of AU-L tablets have been studied and their sorption capacity has been determined. The new technology will be implemented at the Tashkent Pharmaceutical Plant (Uzfarmprom Company). __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 5, pp. 49–52, May, 2007.  相似文献   
995.
A highly sensitive method for the quantitative determination of a potential antiarrhythmic drug (OF-7976) in the blood plasma has been developed. The method is based on the electron spray ionization/mass spectrometry (ESI-MS) technique without preliminary chromatographic separation and makes use of nibentan as the internal standard. A linear relationship between drug concentration and the peak intensity of ions of the analyzed substance (m/z = 398) and the internal standard (m/z = 382) is established. The detection limit is 3 ng/(0.5 ml plasma). The method is linear from 3 to 25 ng/(0.5 ml plasma) with a correlation coefficient of 0.98. The coefficient of variation was less than 7 %. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 3, pp. 45–48, March, 2007.  相似文献   
996.
Growth of malignant tumors is dependent on sufficient blood supply. Thus, inhibition of tumor angiogenesis is emerging as a promising target in the treatment of malignancies. Human angiostatin (hANG) is one of the most potent inhibitors of endothelial cell proliferation, angiogenesis, and tumor growth in vivo. However, its mechanisms operating in vivo are not well understood. METHODS: To obtain more information about functional changes in the angiogenic process, we established Morris hepatoma (MH3924A) cell lines expressing hANG (hANG-MH3924A). The effects of hANG expression on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) were measured in coculture experiments in vitro. To evaluate changes in tumor perfusion and blood volume, H2 15O and 68Ga-DOTA-albumin (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid) were used for PET studies in vivo. Additionally, immunohistologic quantification of vascularization, apoptosis, and proliferation as well as gene array analyses were performed. RESULTS: Our in vitro experiments demonstrate reduced proliferation and increased apoptosis in HUVECs when being cocultured with hANG-MH3924A. In support, tumor growth of hANG-MH3924A is diminished by 95% in vivo. However, tumor perfusion and blood volume are increased in hANG-MH3924A corresponding to an increased microvessel density. Furthermore, hANG-transfected tumors show changes in expression of genes related to apoptosis, stress, signal transduction, and metabolism. CONCLUSION: hANG expression leads to inhibition of tumor growth, increased apoptosis, and changes in the expression of multiple genes involved in stress reactions, signal transduction, and apoptosis, which indicates a multifactorial reaction of tumors. An enhanced microvessel density is seen as part of these reactions and is associated with increased perfusion as measured by PET.  相似文献   
997.
998.
Osteoporosis is a common disease with a strong genetic component characterized by reduced bone mass and an increased risk of fragility fractures. Bone mineral density (BMD) is the most important determinant of osteoporotic fracture risk, but the genes responsible for BMD regulation and fracture are incompletely defined. To enable multi-center studies to examine the genetic influences on BMD there is a requirement to standardize measurements across different manufacturers of bone densitometers, different versions of machines and different normative ranges. This paper describes a method developed to allow near-identical subjects with low age-adjusted BMD (based on Z-scores) to be recruited in 17 centers using 27 different densitometers. Cross-calibration was based on measurements using a European spine phantom circulated to all centers and measured ten times on each individual machine. From theses values an individual exponential curve, based on nominal versus observed BMD, was derived for each machine. As expected, there were large and significant variations in nominal BMD values, not only between scanners from different manufacturers but also between different versions of scanners from the same manufacturer. Hologic scanners tended to underestimate the nominal BMD, while Lunar scanners overestimated the value. Norland scanners gave mixed values over estimating BMD at the lower nominal value (0.5 g/cm2) while underestimating the value at the higher value (1.5 g/cm2). The validity of the exponential equations was tested using hip and spine measurements on 991 non-proband women from a familial osteoporosis study (FAMOS). After cross-calibration there was a considerable reduction in variation between machines. This observation, coupled with the absence of a similar reduction in variation attributable to a linear regression on age, demonstrated the validity of the cross-calibration approach. Use of the cross-calibration curves along with a standard normative range (in the case of this study, the Hologic normative range) allowed age-specific Z-scores to be used as an inclusion criterion in this genetic study, a method that will be useful for other trials where age-specific BMD inclusion criteria are required.  相似文献   
999.
OBJECTIVE: Conventional surgical management of prolapsing haemorrhoids is by excisional haemorrhoidectomy. Postoperative pain has restricted the application of such procedures in the day case setting. These operations remain associated with a period of restricted activity. The use of circular stapling devices as an alternative to the excisional approach in the management of haemorrhoids has been described. This study reports our experience of stapled haemorrhoidopexy as a day case procedure. METHODS: Patients with third or fourth degree haemorrhoids were eligible for the procedure. Patients were considered suitable candidates for day case surgery based on conventional parameters. Symptoms were assessed using a previously validated symptom severity rating score. Stapled haemorrhoidopexy was carried out using a circular stapling device. Pain scores were obtained prior to discharge. Patients were admitted if pain was uncontrolled despite oral analgesia. Symptoms were re-scored at six-week follow-up. RESULTS: Over a 70-month period 168 consecutive stapled haemorrhoidopexies were performed or directly supervised by one consultant colorectal surgeon. One hundred and ten (65%) patients were considered appropriate candidates for day case surgery by conventional criteria. Ninety-six (87.3%) patients successfully underwent stapled haemorrhoidopexy on a day case basis. Fourteen (12.7%) patients required admission on the day of surgery (5 for early postoperative bleeding, 4 for pain necessitating continuing opiate analgesia, two for urinary retention and three for surgery performed late in the day). Six (5%) patients were re-admitted postoperatively; four for pain relief and two because of urinary retention. Of the day case patients, 91 (82.7%) and 56 (50.9%) had been seen for 6 week and 6 month review, respectively, at the time of analysis. Symptom scores were 6 (pre-operatively) vs 0 (postoperatively) (P < 0.01). 76/91 (83.5%) patients reviewed at 6/52 were asymptomatic. CONCLUSION: Stapled haemorrhoidopexy is a safe and effective procedure that can be carried out on selected patients on a day case basis. Complications are of a similar nature to excisional haemorrhoidectomy.  相似文献   
1000.
Most of the papers published on spigelian hernia are either case reports or small retrospective series. In this prospective multicenter study, we aimed to outline the specific features of spigelian hernias and patients’ characteristics more clearly. Surgeons enrolled patients to be entered into the database as they diagnosed and treated the hernias at will. The baseline and surgical outcome parameters were noted in each patient. A painful mass was the main presenting complaint in half of 34 patients. Accurate preoperative diagnosis was possible in 31 patients. Open intraperitoneal mesh repair was the preferred technique. The mean hospital stay and time until return to normal daily activities were 4.1 and 15.6 days. Although a rare condition, diagnosis of a spigelian hernia is not difficult once remembered. Its surgical repair seems to cause few complications and is very well tolerated by the patient.  相似文献   
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