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91.
A case of right atrial myxoma is described. The patient had vague and variable symptoms and it was not until five years after first presentation that she had developed clinical and electrocardiographic evidence of right atrial hypertrophy, and angiocardiographic evidence of a fist-sized myxoma which was subsequently removed surgically. 相似文献
92.
MB Rall' 《Canadian Metallurgical Quarterly》1976,116(6):116-118
93.
SME市场对那些能够带来些有用东西的新进者们开了大门.在对中小型企业(SME)的调研中我们试图预测他们的期望是什么?以及他们对目前的产品是否满意.我们在门户网站www.crm4sme.com的会员中进行了投票,有近2500位中小企业的经理/职员参与.其中约10%(228人)的人作出了响应. 相似文献
94.
95.
MB Danielov 《Canadian Metallurgical Quarterly》1977,13(7):1305-1309
In the course of investigation of 262 families with non-differentiated forms of oligophrenias it is established that in 48 families (18.3%) mental deficiency in sibs is caused by pathological mutations in the X-chromosome. Besides, it is not excluded that in certain inbred families oligophrenia in female persons is also, due to mutations linked with X-chromosome. This is supported by the dependence established between the frequency of the cases of oligophrenia among female persons and the inbreeding coefficient for the X-linked loci. The possibility of manifestation of the recessive genes of oligophrenia linked with X-chromosomes in heterozygous state is discussed. 相似文献
96.
MB Poh-Fitzpatrick 《Canadian Metallurgical Quarterly》1977,3(2):199-204
Adverse effects of excessive cutaneous exposure to solar radiation are hazards of considerable importance. As public health measures, new attitudes about sunbathing and new practices to counteract those adverse effects, especially for high-risk individuals, appear warranted. 相似文献
97.
We have developed an optical delivery device (catheter) capable of transmitting broadband infrared light (IR wavelengths from 2 to 10 microm) for both diagnostic and therapeutic applications. The catheter is 1.68 mm in outer diameter and 1 m in length. It consists of two hollow glass waveguides coupled to a high-refractive-index optic tip. The IR light interacts with the tissue at the optic-tissue interface to measure the spectral signatures and perform therapy on the tissue at this interface. Fourier-transform IR spectrophotometer light is used to obtain the spectral signatures, and an IR free-electron laser (FEL) is used to study the therapeutic interaction of evanescent waves with the tissue. We present our catheter design; preliminary IR spectroscopy of aorta, blood, fatty tissue, and muscle; and IR FEL therapy on atheroslerotic aorta. 相似文献
98.
Belyea RL Curry RD Mesyats GA Filatov AL Clevenger TE Miller MA Youngquist RS 《Journal of dairy science》2001,84(12):2777-2781
A study was carried out to measure the growth and germinal tissue responses of young bull calf whose testicles were exposed to different levels of high energy, pulsed beams (X rays). Treatments (absorbed doses) were 0, 1530, 1980, 3060, or 6300 rads. Body weights were measured monthly for 10 mo; testosterone concentrations were measured in mo 2 and 5. At the end of the study, scrotal circumferences were measured, and testes were removed and weighed. Sections of testes were taken, processed, and evaluated for effects on germinal epithelium. Treatments did not affect body weights or weight gains. Testosterone concentrations at mo 5 generally decreased with increased energy dose. Testicular weights were not different among treatments; generally, scrotal circumferences decreased and germinal tissue degeneration increased as the absorbed dose was increased. 相似文献
99.
P Cocco P Todde S Fornera MB Manca P Manca AR Sias 《Canadian Metallurgical Quarterly》1998,91(2):706-709
The objective of this study was to test the hypothesis of a lower mortality from cancer and cardiovascular diseases among men expressing glucose-6-phosphate dehydrogenase (G6PD) deficiency. We designed a mortality study based on death certificates from January 1, 1982 through December 31, 1992 in a cohort of G6PD-deficient men. Cohort members were 1,756 men, identified as expressing the G6PD-deficient phenotype during a 1981 population screening of the G6PD polymorphism. The setting was the island of Sardinia, Italy. Outcome measures were cause-specific standardized mortality ratios (SMRs), which were computed as 100 times the observed/expected ratio, with the general Sardinian male population as the reference. Deaths from all causes were significantly less than expected due to decreased SMRs for ischemic heart disease (SMR, 28; 95% confidence interval [CI], 10 to 62), cerebrovascular disease (SMR, 22; 95% CI, 6 to 55), and liver cirrhosis (SMR, 12; 95% CI, 0 to 66), which explained 95.6% of the deficit in total mortality. All cancer mortality was close to the expectation, with a significant increase in the SMR for non-Hodgkin's lymphoma (SMR, 545; 95% CI, 147 to 1,395). A decrease in mortality from cardiovascular diseases was one of the study hypotheses, based on an earlier human report and experimental evidence. However, selection bias is also a likely explanation. Further analytic studies are warranted to confirm whether subjects expressing the G6PD-deficient phenotype are protected against ischemic heart disease and cerebrovascular disease. This cohort study is consistent with more recent case-control studies in rejecting the hypothesis of a decreased cancer risk among G6PD-deficient subjects. The observed increase in mortality from non-Hodgkin's lymphoma and decrease in mortality from liver cirrhosis were not previously reported. 相似文献
100.
Mibefradil is a new cardiovascular drug with peculiar Ca++ antagonistic properties. The most remarkable feature of mibefradil is its unique relative selectivity for T type calcium channels, a property that has been proposed to explain in part the beneficial pharmacological and clinical profiles of this drug. In adrenal glomerulosa cells, aldosterone biosynthesis and secretion in response to angiotensin II or extracellular potassium is dependent on a sustained influx of Ca++ through T type Ca++ channels. The effect of mibefradil on the steroidogenic function of glomerulosa cells was therefore investigated. Using the patch clamp technique, we found that mibefradil inhibits selectively and in a concentration-dependent manner (IC50 = 3 microM)++ T type currents in bovine glomerulosa cells. In addition to this tonic (voltage independent) inhibition, the drug also induced a shift of the steady-state inactivation curve of these channels toward hyperpolarized voltages, contributing to its efficacy to prevent Ca++ influx into the cell through T type channels. Concomitantly, mibefradil reduced the cytosolic calcium responses to potassium and angiotensin II (as assessed with fluorescent probes), without affecting the capacitative Ca++ influx, and inhibited pregnenolone and aldosterone formation. This inhibition of steroidogenesis was not exclusively due to mibefradil action on voltage-operated Ca++ channels, because this agent also partially reduced steroid synthesis induced by adrenocorticotropic hormone or forskolin, two activators of the cyclic AMP pathway. In conclusion, mibefradil is highly effective in adrenal glomerulosa cells in reducing T type channel activity and aldosterone biosynthesis, two actions that should contribute to the beneficial effect of the drug in the treatment of hypertension. 相似文献