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101.
The autopsy of an infant with the 4p- or Wolf-Hirschhorn syndrome revealed visceral abnormalities not previously described, i.e., agenesis of the gallbladder and spleen. The parent's chromosomes were normal.  相似文献   
102.
Phosphatidylinositol turnover and calcium movement in the rat pancreas   总被引:1,自引:0,他引:1  
Carbamylcholine, bombesin, pancreozymin, and pentagastrin elicited a similar increase in amylase secretion and phosphatidylinositol turnover in rat pancreatic fragments. The concentration of each secretagogue that provoked half-maximal stimulation of amylase secretion was three to six times lower than that which induced half-maximal stimulation of phosphatidylinositol turnover. The increased turnover of phosphatidylinositols due to carbamylcholine or pancreozymin, but not the secretory response, persisted in a calcium-free medium or in 90% heavy water. The replacement of the media Na+ with Li+ increased an atropine-resistant turnover of phosphatidylinositols, but did not stimulate secretion. The ionophore A-23187 (in a medium containing 2.5 mM Ca2+) and 10 mM NaF induced a high secretory response, but exerted no effect on phosphatidylinositol turnover. K+ at a 70 mM concentration provoked a phosphatidylinositol effect and hypersecretion. Secretin, vasoactive intestinal peptide, dibutyryl cAMP, dibutyryl cGMP, 8-bromo cGMP, and N2-monobutyryl cGMP stimulated amylase secretion without an increased turnover of phosphatidylinositols. It is concluded that, in the rat pancreas, the increased turnover of phosphatidylinositols was directly associated with secretagogues inducing calcium movements.  相似文献   
103.
Recent electrophysiological studies have identified novel ion channel activity in the host plasma membrane of Plasmodium falciparum -infected human red blood cells (RBCs). However, conflicting data have been published with regard to the characteristics of induced channel activity measured in the whole-cell configuration of the patch-clamp technique. In an effort to establish the reasons for these discrepancies, we demonstrate here two factors that have been found to modulate whole-cell recordings in malaria-infected RBCs. Firstly, negative holding potentials reduced inward currents (i.e. at negative potentials), although this result was highly complex. Secondly, the addition of human serum increased outward currents (i.e. at positive potentials) by approximately 4-fold and inward currents by approximately 2-fold. These two effects may help to resolve the conflicting data in the literature, although further investigation is required to understand the underlying mechanisms and their physiological relevance in detail.  相似文献   
104.
To study the role of Mycoplasma hominis and T-mycoplasmas (Ureaplasma urealyticum) in chorioamnionitis, we obtained culture from 249 puerperal women and their babies. The placentas were examined histologically. Infants whose placentas showed inflammation (chorioamnionitis) had cultures positive for T-mycoplasmas more frequently (37.5 per cent) than those with normal placentas (19.0 per cent) (P = 0.021). Colonization with M. hominis was found in 16.0 per cent of the babies and was not significantly associated with chorioamnionitis. Material colonization with mycoplasmas was more frequent (73.4 per cent) and was not correlated with placental inflammation. We conclude that a substantial proportion of cases of chorioamnionitis may be caused by prenatal infection with T-mycoplasmas. The fact that these organisms are not highly virulent could explain the frequent finding of inflammed placentas from otherwise normal pregnacies. No adverse clinical effects of the placental lesions or of mycoplasmal colonization could be detected in this small study.  相似文献   
105.
Male rats were submitted for 3 wk either to portacaval shunt or to portacaval transposition. In both cases, sham-operated pair-fed rats served as controls. After an overnight fast, insulinemia was similar in all groups, but glucagonemia was significantly higher (by 65%) and serum glucose significantly lower (by 35%) in rats with a portacaval shunt. The lipid metabolism of epididymal adipose tissue was studied in vitro, as well as in vivo. In rats with a portacaval shunt, in vitro lipogenesis from [U-14C]glucose, [1-14C]acetate, or 3H2o was 60-80% lower than in sham-operated pair-fed controls. Twice as much in vitro basal lipolysis could be determined. In addition, in vivo lipogenesis from 3H2O was markedly decreased (6 times). By contrast, in rats with portacaval transposition, in vitro lipogenesis was higher (by 80-140%) and basal lipolysis lower (by 63%) than in pair-fed controls. Thus, even when the nutritional state was taken into consideration, the type of portal diversion was the determining factor in influencing lipid metabolism in epididymal adipose tissue.  相似文献   
106.
Virus isolation and titration, electrocardiography, enzyme assays and light and electron microscopic studies were undertaken in male turkeys infected with influenza A/turkey/Ontario/7732/66 virus to determine its potential role in the genesis of heart disease. Virus was isolated from the heart initially before a demonstrable viremia and terminally in declining serum viral titer. Virus was isolated from the heart muscle as early as 1 day postinoculation. Highest viral titers were found in the heart at 6 days postinoculation and coincided with maximum elevations of serum glutamic-oxalacetic transaminase and lactic acid dehydrogenase, microscopic lesions in the heart and cardiac arrhythmias. Microscopic lesions in the heart were first detected at 4 days postinoculation and consisted of disseminated areas of necrosis, focal myocarditis, pericarditis and endocarditis. Alterations in myocardial ultrastructure which followed viral infection included fragmentation and dissolution of myofibrils, dilation of the sarcotubular system, increase in membrane vesicle formation in the region of the endoplasmic reticulum, discontinuity of the sarcolemma, proliferation of mitochondrial population, swelling of mitochondria with separation and disruption of the cristae, and the presence of intramitochondrial and perinuclear densities.  相似文献   
107.
108.
The increasing complexity of diseases and advancing medical technologies have recently raised the number of test items and their use. This has caused each department to ask for clinical support by medical technologists, including consultation services on clinical laboratory tests in Japan. Under these circumstances, we think it is necessary to consider a Japanese education system for medical technologists to foster people with advanced ability capable in providing adequate clinical support. It is important that we study medical technologist systems and education systems superior to than ours. Therefore, to investigate the state of the Japanese education system for medical technologists, we conducted a comparison between the medical technologist systems and education systems in foreign countries and those of Japan. The social background in which medical technologists are positioned, their scope of work, and the education systems overseas are different from Japan on many points and we were given many suggestions for what a system in Japan should be like.  相似文献   
109.
In order to approximate and adhere to mucosal epithelial cells, Candida must traverse the overlying mucus layer. Interactions of Candida species with mucin and human buccal epithelial cells (BECs) were thus investigated in vitro. Binding of the Candida species to purified small intestinal mucin showed a close correlation with their hierarchy of virulence. Significant differences (P < 0.05) were found among three categories of Candida species adhering highly (C. dubliniensis, C. tropicalis, and C. albicans), moderately (C. parapsilosis and C. lusitaniae) or weakly (C. krusei and C. glabrata) to mucin. Adherence of C. albicans to BECs was quantitatively inhibited by graded concentrations of mucin. However, inhibition of adherence was reversed by pretreatment of mucin with pronase or C. albicans secretory aspartyl proteinase Sap2p but not with sodium periodate. Saturable concentration- and time-dependent binding of mucin to C. albicans was abrogated by pronase or Sap2p treatment of mucin but was unaffected by beta-mercaptoethanol, sodium periodate, neuraminidase, lectins, or potentially inhibitory sugars. Probing of membrane blots of the mucin with C. albicans revealed binding of the yeast to the 66-kDa cleavage product of the 118-kDa C-terminal glycopeptide of mucin. Although no evidence was found for the participation of C. albicans cell surface mannoproteins in specific receptor-ligand binding to mucin, inhibition of binding by p-nitrophenol (1 mM) and tetramethylurea (0.36 M) revealed that hydrophobic interactions are involved in adherence of C. albicans to mucin. These results suggest that C. albicans may both adhere to and enzymatically degrade mucins by the action of Saps, and that both properties may act to modulate Candida populations in the oral cavity and gastrointestinal tract.  相似文献   
110.
In acute lymphoblastic leukaemia the combination prednisone-vincristine induces more than 85% complete remissions. L-asparaginase which was used in complete remissions, seemed to increase their duration. Actually the best maintenance treatment consists in the combination of 6-mercaptopurine and methotrexate interrupted by reinductions. In other respects C.N.S. prophylaxis with intrathecal methotrexate and craniospinal irradiation is necessary. The well-known prognostic factors are: age, leucocytosis, tumoral syndrome, and cytological type: 216 cases of long remission have been observed. One group of these patients was treated by old methods: this represents 0.8 to 1% of the material, while 20% were treated by recent protocols with reinductions (20%).  相似文献   
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