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81.
EK Molchanova 《Canadian Metallurgical Quarterly》1976,76(5):736-741
The author examined 131 patients with conditions of deep and durative remissions who had not been hospitalized during the past 20 years. Clinically they were characterized by some common traits. In most of the cases the premorbid personality and the character during the state of remission had hypersthenic traits. Manifest psychoses were seen mainly from 25-45 years. The subsequent development of the disease had infrequent prevalently affective-delusional attacks with a tendency to an intensification of phasic disorders in the involutional period and a subsequent regressive development of the disease in all cases in senescence. 相似文献
82.
Dipyridamole, which is known to alter platelet function, has also been shown to reduce hypoxic pulmonary vasoconstriction. This latter effect could result from dipyridamole either acting on a platelet-mediated system, or acting directly on pulmonary vascular smooth muscle. To investigate these two possibilities, normal dogs were compared with dogs rendered thrombocytopenic by a platelet antiserum. Compared with the hypoxic pressor response before drug treatment, the hypoxic response following dipyridamole was only 32% as great in the normal dogs and only 38% as great in the thrombocytopenic dogs. Thus, dipyridamole was no less effective in reducing the hypoxic pressor response in the virtual absence of platelets. This supports a direct effect of dipyridamole on pulmonary vascular smooth muscle, which could be mediated by an increase in adenosine levels. 相似文献
83.
S. LIPOVEK DELAKORDA I. LETOFSKY-PAPST† T. NOVAK M. GIOVANNELLI‡ F. HOFER† & M.A. PABST§ 《Journal of microscopy》2008,231(1):38-46
In this case study we present an application of different analytical electron microscopic methods in biology, to elucidate their usefulness in such investigations. Using analytical electron microscopy, spherites in the digestive gland cells of the helicid snail Chilostoma lefeburiana were examined at three stages: just before the non-feeding period of over-wintering in November, in the middle of over-wintering in February and at its end in March. A detailed characterization of changes in the elemental composition of the spherites was characterized by a combination of transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDXS), electron energy-loss spectroscopy (EELS) and energy filtering TEM (EFTEM). During over-wintering, the spherites passed the following changes. Before over-wintering in November, they consisted of striking concentric layers of electron-dense and electron-lucent zones, while in February and March they showed clear empty zones between materials of different electron density. In November spherites, C, O, Ca, P, Cl, Fe, Si, Na, K, Mg and S were detected, whereas in February ones C, O, N, Cl, Si and S were found and only C, O, N, Si and Cl were detected in March spherites. It is suggested that the elements missing in February and March were used in different physiological processes during over-wintering, like (1) the maintenance of the appropriate elemental composition of the internal environment, (2) accumulation of non-toxic waste materials that cannot be metabolized and (3) avoiding potential intoxication by contamination with toxic metals. 相似文献
84.
Magnetic resonance imaging findings of median nerve hamartoma are presented in three patients with palpable wrist masses and median neuropathy. Fat-suppressed T1-weighted images demonstrated adipose tissue separating the neural and fibrous tissue bundles in two of three patients, which results in the distinctive appearance of these tumors on magnetic resonance imaging. Fibrous tissue appeared as enhancing longitudinal bundles within the tumor on gadolinium enhanced fat-suppressed T1-weighted images. 相似文献
85.
EK Khusnutdinova TV Viktorova IM Khidiiatova RI Fatkhlislamova TE Ivashchenko 《Canadian Metallurgical Quarterly》1997,33(9):1291-1296
Data on allelic polymorphism of MET and D7S23 DNA loci linked to the human cystic fibrosis gene studied in three Bashkir ethnic groups and some Volga-Ural populations (Tartars, Maris, Mordovians, Udmurts, Chuvashs, and Komis) are presented. Udmurts were found to be substantially different from Bashkirs, Tartars, Mordovians, and Chuvashs by the allele frequency distribution observed for MET, while Komis and Bashkirs differed by this parameter from Mordovians and Maris. Comparative analysis of restriction fragment length polymorphism (RFLP) at the D7S23 locus revealed statistically significant differences in genotype frequencies between Bashkirs of the Arkhangel' skii region and populations of Mordva and Udmurtia. In this respect, the Mordovian population appeared to be notably different from the populations of Bashkortostan, Tatarstan, Marii-El, Udmurtiya, Chuvashiya, and Komis. Genetic distances were calculated and corresponding dendrograms were constructed on the basis of data on Met-H, CS.7, and the ApoB locus hypervariable region allelic frequencies. Three ethnogeographic Bashkir groups belonging to one tree branch were found to be closely related to the populations of Tartars, Maris, Udmurts, and Chuvashs and substantially different from Komis and Mordovians. Thus, the position of Volga-Ural populations on the dendrogram corresponds to the degree of relationship between the Finno-Ugric and Turkic populations, confirming the usefulness of DNA polymorphism analysis for the study of the genetic structure of populations. 相似文献
86.
R Mann EK Yeong ML Moore LH Engrav 《Canadian Metallurgical Quarterly》1997,18(2):160-3; discussion 159
This article introduces a new tool to measure the pressure that is under pressure garments. The Iscan (Tekscan, Inc.) system uses a patented ultra-thin (0.007 inch) sensor with multiple sensing locations that sample continuously at 100 times per second. It is noninvasive, convenient, and quick. The study had two parts. First, we established the validity and reliability of the device. Next, garment/scar interface pressures were measured on new garments with use of the Iscan system. Four garment types were studied, with 10 measurements made in each group: Isotoner gloves (Smith & Nephew Roylan, Inc.); custom-fit pressure gloves; Tubigrip forearm sleeves (Seton Health Care Group); and custom-fit pressure forearm sleeves. Mean garment/scar interface pressures were 18 +/- 2 mm Hg for the Isotoner glove, 34 +/- 5 mm Hg for the custom-fit pressure glove, 20 +/- 7 mm Hg for the Tubigrip sleeve, and 35 +/- 6 mm Hg for the custom-fit sleeve. We concluded that the Iscan system can be used to measure pressure under pressure garments accurately and reliably, and that custom-fit hand and forearm garments provide more pressure than Isotoner gloves or Tubigrip sleeves. 相似文献
87.
P Franz S Aharinejad A Miksovsky DE Schraufnagel EK Larson SC Marks 《Canadian Metallurgical Quarterly》1997,112(1-2):33-43
Serum levels of the vasoconstrictor endothelin-1 (ET-1) increase in ischemia and systemic hypertension. We examined the effects of ET-1 on the cochlear microvasculature. Blood vessels were cast with methacrylate in adult male Wistar Kyoto rats, 10 min after intravenous injection of ET-1 (1.0 microg/kg); control animals received saline. Systemic blood pressure was recorded continuously. ET-1 increased the average systolic pressure by 18% and average diastolic pressure by 22% (P < 0.01). Scanning electron microscopy of cast vessels showed multiple circumscribed luminal constrictions on: (1) postcapillary venules; (2) collecting veins; (3) where collecting veins merged with the spiral modiolar vein; (4) on the spiral modiolar vein itself. Circumscribed constrictions in arteries were not observed. In ET-1 injected animals focal contractions of collecting veins reduced luminal width by 13.4% +/- 2.9 (P < 0.01). In control rats, constrictions on venous casts were minimal and constrictions on arteries were not observed. The present study shows that ET-1 is involved in local control of cochlear blood flow in that it focally contracts cochlear veins. It is suggested that this might be due to the high affinity of ET-1 receptors and/or the large number of ET-1 receptors on contractile cells in venous walls. 相似文献
88.
MK Mau A Grandinetti RF Arakaki HK Chang EK Kinney JD Curb 《Canadian Metallurgical Quarterly》1997,20(9):1376-1380
OBJECTIVE: To investigate whether fasting hyperinsulinemia is associated with a clustering of cardiovascular disease (CVD) risk factors, manifesting as the insulin resistance syndrome (IRS), in a population of native Hawaiians. RESEARCH DESIGN AND METHODS: A total of 574 native Hawaiians > or = 30 years of age were examined for blood pressure, waist-to-hip ratio (WHR), BMI, oral glucose tolerance, and fasting lipid, insulin, and C-peptide concentrations. All statistical analyses (n = 384) excluded 190 individuals who had NIDDM or who were taking hypertension medication. Using logistic regression analysis, fasting insulin and C-peptide levels were compared with CVD risk factors (glucose intolerance, hypertension, central adiposity, elevated triglyceride levels, and low HDL cholesterol levels) after adjusting for age and obesity. RESULTS: Sixty-six percent of native Hawaiians were overweight or obese, and 70% were found to have central adiposity. Fasting insulin concentrations were correlated with BMI, WHR, blood pressure, and triglyceride, HDL cholesterol, and glucose concentrations. Fasting insulin was also significantly associated with an increasing number of CVD risk factors in each participant (P < 0.001). Fasting insulin and C-peptide concentrations were independently associated with glucose intolerance, high triglyceride levels, and low HDL cholesterol levels. However, only fasting C-peptide concentrations were independently associated with hypertension and central adiposity. Apparent differences in the correlates of fasting insulin and C-peptide may be related to multiple factors and warrant further evaluation. CONCLUSIONS: This study provides cross-sectional data confirming the existence of the IRS in native Hawaiians. However, further longitudinal studies are needed to examine the relationship of insulin resistance and/or surrogate markers to increased rates of NIDDM and CVD mortality in native Hawaiians. 相似文献
89.
The method of determination of the gamma-radiation absorption distribution in microstructures of a biosystem is proposed. The absorption capacity and energy absorption distribution of some biomolecules, mass coefficients and optical density of blood and thyroid gland are calculated. Influence of the pollution of biosystem microstructures (liver, blood, thyroid, gland) by hard elements on the energy absorption distribution is demonstrated. 相似文献
90.
EK Barbour SK Hamadeh C Hilan M Kallas A Eid W Sakr 《Canadian Metallurgical Quarterly》1997,16(3):770-775
From 1992 to mid-1996, a national survey of poultry diseases in Lebanon was conducted. This surveillance included meat breeder, layer breeder, commercial layer and chicken broiler flocks. The history, signs, lesions and laboratory tests of poultry were used in the diagnosis of prevalent poultry diseases. Culture techniques were used to screen for bacterial diseases; serological techniques and, to a lesser extent, culture techniques were used to diagnose viral diseases; and both serological and culture techniques were used to diagnose Mycoplasma infections. The outbreaks of diseases detected in broiler breeder flocks and the number of such flocks experiencing these diseases were as follows: femoral head necrosis (6), egg-drop syndrome (3), reovirus-associated malabsorption syndrome (3), synovitis (Mycoplasma synoviae infection) (7), swollen head syndrome (SHS) (3), tenosynovitis (viral arthritis) (1), lymphoid leukosis (3), avian encephalomyelitis (1), fowl pox (1) and aortic rupture (1). The disease outbreaks detected in layer breeders were as follows: SHS (2), bumble foot (2), egg-drop syndrome (3) and avian infectious bronchitis (IB) (1). The disease outbreaks detected in commercial layer flocks were as follows: egg-drop syndrome (5), avian infectious laryngotracheitis (2), avian IB (nephrogenic strain) (1), malabsorption (1), avian tuberculosis (Mycobacterium avium) (1), Marek's disease (1), fowl pox (1), Salmonella enterica subsp. enterica Enteritidis infection (1), salpingitis (1) and Heterakis gallinae infestation (1). The disease outbreaks detected in broiler flocks were as follows: colibacillosis (40), infectious bursal disease (Gumboro disease) (15), malabsorption syndrome (8), avian infectious laryngotracheitis (8), paratyphoids (salmonellosis) (7), femoral head necrosis (8), SHS (6), avian mycoplasmosis (Mycoplasma gallisepticum infection) (6), synovitis (7), avian IB (6), botulism (1), avian encephalomyelitis (1) and gangrenous dermatitis (1). Diseases which occurred and which were reported for the first time in Lebanon were as follows: bumble foot, femoral head necrosis, avian IB (nephrogenic strain), malabsorption syndrome and SHS. This surveillance helped to establish baseline data concerning the predominant poultry diseases in Lebanon. Such information is a prerequisite for future regional and international collaboration to identify the source of the aetiological agents and to control their spread to neighbouring countries. 相似文献