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971.
S Rahman RB Blok HH Dahl DM Danks DM Kirby CW Chow J Christodoulou DR Thorburn 《Canadian Metallurgical Quarterly》1996,39(3):343-351
The morphology and number of cells in the trophectoderm (TE) and inner cell mass (ICM) of buffalo blastocysts derived from in vitro fertilization and cultured in the presence or absence of insulin-like growth factor-I (IGF-I) were analyzed by differential fluorochrome staining technique. The total cell number (TCN), TE number, and ICM cell number were significantly higher in blastocysts developed in vitro in the presence of IGF-I as compared to blastocysts developed without IGF-I (P < 0.01). It was observed that the buffalo blastocyst took 5-9 days postfertilization to develop in vitro. In order to correlate the time required for blastocyst development and the allocation of cells to TE and ICM, blastocysts were designated as fast (developing on or before day 7) or slow (developing after day 7). The TCN, TE, and ICM cells of fast-developing blastocysts cultured in the presence of IGF-I were significantly higher than slow-developing blastocysts (P < 0.01). The blastocysts developed on day 6 had a mean total cell number 118.6 +/- 21.4, which significantly decreased to 85.6 +/- 17.4, 62.0 +/- 14.5, and 17.0 +/- 4.0 on days 7, 8, and 9, respectively (P < 0.05). Normal development of buffalo embryo showed that, on average, embryos reached compact morula stage at the earliest between days 4.5-5.5. Blastocysts developed, at the earliest, between days 5.0-6.0, and it took them, on average, 6.5 days to hatch from the zona pellucida. TCN, TE, and ICM increased three times from morula to blastocyst; however, the proportion of ICM to TCN remained the same, in both embryonic stages. TE approximately doubled in hatched blastocysts, as compared to unhatched blastocysts (P < 0.05). However, ICM cells were decreased. The time required for development of parthenogenetic blastocysts was observed to be greater as compared to in vitro fertilized (IVF) blastocysts. The total cell number of parthenogenetic blastocysts was 100.8 +/- 11.3, including 59.2 +/- 8.4 cells of TE and 42.1 +/- 6.9 cells of ICM. 相似文献
972.
DG Federman JT Trent CW Froelich J Demirovic RS Kirsner 《Canadian Metallurgical Quarterly》1998,44(5):58-62, 64, 66 passim
It is estimated that peripheral vascular disease (PVD) affects 30 percent of the adult population, and two-thirds of all cases are asymptomatic. Detecting PVD can be relatively easy and inexpensive, and based either on subjectively supplied historical information (claudication) or upon physical examination findings [ankle-brachial index (ABI)]. The ABI may serve as a marker for increased risk for systemic vascular disease as an abnormally low ABI has been shown to be associated with systemic vascular disease. Epidemiology of and risk factors for PVD are in similar to coronary heart disease. PVD is uncommon until middle age and then increases dramatically. Prevalence of PVD is slightly higher in men than women, yet this tends to diminish with age. Cigarette smoking is probably the most important risk factor for PVD. Hypertension, hypercholesterolemia, and diabetes are also risk factors for the development of symptomatic PVD. Conversely, the presence of a high degree of physical activity and higher levels of HDL-cholesterol as well as a lower body mass index (BMI) are protective. Patients who have vascular disease in one organ system often exhibit evidence of vascular disease elsewhere. Presence of coronary artery disease among patients with symptomatic PVD is between two and four times higher than those without PVD, and PVD is also associated with cerebrovascular disease. 相似文献
973.
BK Ko HR Cho DW Choi CW Nam CJ Park GY Kim SS Kim YJ Woo J Huh MY Kim 《Canadian Metallurgical Quarterly》1998,13(3):286-290
The abuse of zipeprol, an antitussive agent, was found to be most prevalent among young people in Korea. Because abusers take large doses of this drug for its hallucinogenic effects, fatalities from zipeprol overdose abuse have been on the rise since 1991. Since 1991, a total of 69 zipeprol-related deaths have occurred throughout the nation. A demographic study shows that in ninety six percent of cases involving ziperol alone, the victims were in their teens and twenties. The male/female ratio in zipeprol related death was 3.5:1. Most of these zipeprol-associated deaths occurred in the larger cities of Seoul and Inchon. The blood concentration of zipeprol ranged from 0.8 to 38.3 micrograms/mL in single drug involved deaths, while zipeprol varied from 0.1 to 35.3 micrograms/mL in zipeprol and dextromethorphan victims. 相似文献
974.
FR Cagampang HD Piggins WJ Sheward AJ Harmar CW Coen 《Canadian Metallurgical Quarterly》1998,813(1):218-222
A receptor for pituitary adenylate cyclase activating polypeptide (PACAP), denoted as PAC1, is expressed in the suprachiasmatic nuclei (SCN). Since the circadian clock demonstrates phase-dependent sensitivity to PACAP, we have used in situ hybridization histochemistry to examine whether PAC1 mRNA is differentially expressed in the rat SCN across the 24-h cycle. There was a significant variation in PAC1 mRNA within the SCN and supraoptic nuclei during the light-dark cycle and in constant darkness, with peaks at the middle of both the real and subjective day and night; no significant variation was observed in the cingulate cortex. The results suggest that the phase-dependent actions of PACAP on the clock may involve phase-specific changes in the availability of PAC1 receptors within the SCN. 相似文献
975.
A Felcher C Commichau Q Cao MJ Brown A Torres CW Francis 《Canadian Metallurgical Quarterly》1998,51(2):629-631
Status epilepticus has been associated with disseminated intravascular coagulation (DIC), but little is known regarding the pathogenesis of this uncommon association. We describe a 41-year-old woman with status epilepticus resulting in death in whom laboratory data demonstrated profound activation of the coagulation and fibrinolytic systems; autopsy findings were consistent with DIC. The occurrence of DIC in status epilepticus may be related to widespread endothelial damage secondary to seizure-induced hyperpyrexia. Body temperature should be closely monitored in patients with prolonged seizures. 相似文献
976.
Findings from empirical research serve as the foundation for neuropsychological assessment of individuals suspected of exposure to formaldehyde. Insofar as conclusions regarding causal relationships between exposure and neuropsychological deficits are based on research methodologies that are reliable, findings can be informative. Unfortunately, existing research is not rooted in sound methodology and findings may mislead rather than enlighten clinicians. Two prominent shortcomings in formaldehyde research are discussed: selection bias in recruitment of research participants and unreliability of participant recall for obtaining data on important background variables and exposure levels. Selected examples illustrate the influence of these shortcomings on research showing a causal relationship between long-term, low-level exposure to formaldehyde and chronic neurobehavioral deficiencies. The implications of these weaknesses for assessment of individual patients are discussed. 相似文献
977.
D Van Buren J Payne S Geevarghese R MacDonell W Chapman JK Wright JH Helderman R Richie CW Pinson 《Canadian Metallurgical Quarterly》1998,30(5):1830-1832
Following primary liver transplantation, immunosuppressive efficacy of Neoral and Prograf was similar and superior to that of Sandimmune. Rejection incidence was statistically increased with Sandimmune therapy. Incidence of hypertension, posttransplant diabetes mellitus, and infectious complications was not statistically different. Although early compromise in renal function was associated with Sandimmune, Neoral, and Prograf immunosuppression, no progressive renal dysfunction was identified. 相似文献
978.
Intraluminal stenting of the gastrointestinal (GI) tract in both multiple intestinal atresias and perforations was used in three patients. In the atresia patients (2), a piercing trocar was used to create continuity of the GI tract and as a guide to thread the intestine over the stent. All patients currently demonstrate normal growth and development on routine enteral feeds. None developed anastomotic leaks or strictures. 相似文献
979.
980.