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991.
992.
GN Piquette JL Tilly LE Prichard C Simón ML Polan 《Canadian Metallurgical Quarterly》1994,1(4):297-301
OBJECTIVE: The purpose of this study was to determine whether cells acquired from individual human preovulatory follicles undergo apoptosis (physiologic cell death) and, if so, to correlate the degree of apoptosis with characteristics of the follicles or the oocytes derived from the follicles. METHODS: We devised a sensitive nonradioactive method for detecting apoptotic DNA fragmentation in small numbers of cells derived from rat atretic follicles and follicular aspirates of patients undergoing assisted reproductive technologies. RESULTS: Using this method, apoptotic DNA was detected in rat atretic follicles, with optimal detection at 10-100 ng. Furthermore, apoptotic DNA was detected in some, but not all individual human follicular aspirates from several patients, and was found in follicles that produced oocytes that fertilized and developed into embryos. CONCLUSION: Apoptosis occurs in cells from human ovarian preovulatory follicles and may be a normal physiologic process of the follicle during luteinization. 相似文献
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996.
JM van Baalen AB Kluit J Maas JL Terpstra JH van Bockel 《Canadian Metallurgical Quarterly》1996,83(12):1729-1734
A retrospective study was carried out of patients from a single institution over a 30-year period. Thirty-one patients presented with 33 fistulas, four non-enteric and 27 enteric. In 25 of 27 patients with a prosthesis-related enteric fistula gastrointestinal bleeding was present. Angiography revealed the fistula in five patients endoscopy in three, and barium studies, echography and computed tomography each revealed one fistula. Six patients died before and five died during operation. In 20 patients various techniques were used for treatment. In-hospital mortality decreased from six of eight patients before 1970, to seven of ten between 1971 and 1980, and to four of 13 after 1981. In the long term, patients treated with an extra-anatomic reconstruction had a poorer prognosis than those treated by in situ reconstruction. This experience shows that diagnostic tests often fail to reveal a prosthesis-related fistula and that mortality can be substantially reduced by early exploration in patients with negative diagnostic studies. 相似文献
997.
The effect of pH on the bleeding of FD&C yellow No. 5 aluminum lake and FD&C red No. 40 aluminum lake was investigated. The pH-bleeding profiles corresponded to the pH-solubility profile of aluminum hydroxide. The similarity of the bleeding profiles of both lake dyes and the pH-solubility profile of aluminum hydroxide indicates that pH related bleeding, other than that occurring by competition with anions, is a result of dissolution of the aluminum hydroxide substrate. This dissolution is related to the properties of the substrate rather than to the structure of adsorbed dye. 相似文献
998.
C de Chillou P Doevendans E Cheriex LM Rodriguez J Metzger F Pieters JL Smeets HJ Wellens 《Canadian Metallurgical Quarterly》1993,14(6):795-798
We studied the relationship between wall motion abnormalities determined by echocardiography and the signal-averaged electrocardiogram in 82 consecutive patients during the acute phase of a first myocardial infarction. An abnormal signal-averaged electrocardiogram was defined as the presence of two of the following criteria: a QRS duration > or = 114 ms, a root mean square voltage (RMS) of the last 40 ms < or = 25 microV and an amplitude signal lower than 40 microV lasting > or = 39 ms. The left ventricle was divided into 13 segments and the contraction pattern divided into akinesia alone (including dyskinesia) (group A), hypokinesia alone (group B) and both hypokinesia and akinesia (group C). An abnormal signal-averaged electrocardiogram was found in 14/82 patients (17%) and was correlated with the persistence of occlusion of the infarct-related vessel (32% vs 9%, P < 0.02). In patients with a patent vessel, the incidence of an abnormal signal-averaged electrocardiogram was 14% in group A, 9% in group B and 0% in group C (NS). In patients with an occluded vessel an abnormal signal-averaged electrocardiogram was found in 10% of group A patients, in 36% in group B patients and in 75% of group C patients (P = 0.05). Our study suggests that the presence of hypokinetic areas during the acute phase of a first myocardial infarction and an abnormal signal-averaged electrocardiogram indicate an occluded infarct-related vessel. 相似文献
999.
TJ Nusbaum JL Graves LD Mueller MR Rose 《Canadian Metallurgical Quarterly》1993,260(5114):1567; author reply 1567-1567; author reply 1569
1000.
An HPLC method has been developed for the analysis of sesquiterpene lactones of the neurotoxic plant Centaurea solstitialis (Asteraceae). The presence of sesquiterpene lactone chlorohydrins in extracts was investigated by means of liquid chromatography-thermospray mass spectrometry. In contrast to earlier reports of a series of mono- and dichlorohydrins from this plant, traces only of two monochlorohydrins could be detected in lipophilic extracts. Model studies carried out with extracts and with the genuine sesquiterpene diepoxide repin and its epimer subluteolide showed that (i) monochlorohydrins can be formed in CHCl3 under usual laboratory conditions; (ii) the epoxide moiety at C-4 of the sesquiterpenes is extremely labile, reacting immediately and quantitatively with traces of HCl to the corresponding monohydrins; (iii) epoxide ring opening at the acyl side chain occurs only at higher HCl concentrations. Confirmation of the peak identity was obtained by the isotope ratio of chlorinated compounds and comparison with authentic samples. The structures of the mono- and dichlorohydrins were established by NMR spectroscopy. 相似文献