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排序方式: 共有4996条查询结果,搜索用时 15 毫秒
991.
Y H Neggers G R Cutter R T Acton J O Alvarez J L Bonner R L Goldenberg R C Go J M Roseman 《The American journal of clinical nutrition》1990,51(4):678-684
A study was conducted on a cohort of 476 women (364 black, 112 white), who attended the Jefferson County Health Department clinic for their prenatal care, to ascertain the relationship between maternal serum zinc concentration measured early in pregnancy and birth weight. For all subjects maternal serum zinc was significantly related to birth weight after various independent determinants of birth weight were controlled for. The data in this study indicate a threshold for maternal serum zinc concentration below which the prevalence of low birth weight increases significantly. Pregnant women who had serum zinc concentrations in the lowest quartile had significantly higher prevalence of low birth weight than did those mothers who had serum zinc concentrations in the upper three quartiles during pregnancy. These findings suggest that maternal serum zinc concentration measured early in pregnancy could be used to identify those women at higher risk of giving birth to a low-birth-weight infant. 相似文献
992.
993.
T Goda K Go Y Matsui K Yasuda T Tanabe 《Kyobu geka. The Japanese journal of thoracic surgery》1992,45(7):604-606
Two cases of partial anomalous pulmonary venous return were reported in whom right pulmonary veins were totally drained to the coronary sinus and to the right atrium respectively. Re-routing of pulmonary veins was done by dilated atrial septal defect and making intra-atrial tunnel using equine pericardial patch. Postoperative courses were uneventful. MRI was useful to identify the pathway from right pulmonary veins to the left atrium. 相似文献
994.
Previous studies have shown that orally administered epidermal growth factor (EGF) enhances neonatal intestinal growth and that it may be absorbed in the intestine and bound by other organs. This study investigated whether the ingestion of EGF would be associated with growth of nonintestinal organs. In short-term studies, 87 newborn rat pups were fed artificial formula containing various concentrations of EGF for 39 h. In long-term studies, suckling newborn pups were fed EGF or an equal volume of distilled water for 5 days. The pups fed formula containing EGF for 39 h had a significant increase in hepatic incorporation of [3H]thymidine into DNA compared with pups not fed EGF. By 5 days of age, 13 pups fed EGF had heavier livers that contained more DNA and RNA compared with 14 control pups. Moreover, EGF-fed pups had heavier hearts and kidneys than pups fed no EGF. These data suggested that ingestion of EGF is associated with the growth of nonintestinal organs. 相似文献
995.
996.
Martha Go?l Brackett Petra E Lockwood Regina L W Messer Jill B Lewis Serge Bouillaguet John C Wataha 《Dental materials》2008,24(4):450-456
OBJECTIVES: The use of lithium disilicate dental ceramics is increasing in dentistry and previous reports have suggested that they may have greater biological risks than previously thought. We tested a hypothesis that composition and processing influence the biological properties of these ceramics. METHODS: The cytotoxicity of two machined and three pressed lithium disilicate materials (n=6) were tested in vitro using mouse fibroblasts in direct contact with the materials for 72h. Cellular response was estimated by mitochondrial succinate dehydrogenase activity (MTT method). Mitochondrial activity was expressed as a percentage of Teflon controls, then compared to Teflon using 2-sided t-tests (alpha=0.05). Polished materials were aged in artificial saliva and tested for cytotoxicity periodically over 6 weeks, then were repolished (320grit SiC paper), aged and tested again for 4 weeks. RESULTS: All materials significantly (50-70%) suppressed cellular mitochondrial activity in the initial week, but suppression decreased by 25-30% over the next 2 weeks. In weeks 4 and 6 some materials exhibited a cytotoxic 'relapse' of 10-20%. The cytotoxic response was no different for machined or pressed materials, but the presence of ZnO had at least an association with longer-term cytotoxicity and relapse. Repolishing to 320grit did not increase cytotoxicity significantly. SIGNIFICANCE: Our results suggest that lithium disilicates are not biologically inert, and that many have a similar cytotoxicity dynamic regardless of small differences in composition or processing. 相似文献
997.
N. H. Cho J. H. Go S. H. Jung W. H. Jung K. K. Lee 《Journal of Korean medical science》1995,10(5):342-351
Fifteen cases of papillary cystic tumor of the pancreas (PCTP) were studied (14 female patients, one male patient; mean age: 23.5 years). Most tumors developed in the head of the pancreas as a well circumscribed large mass. The tumor had a mean diameter of 6.7 cm(range; 2 to 15 cm). Histopathologically abundant delicate papillary fragments, monomorphic tumor cells and degenerative changes of the solid area of the tumor were characteristic. All but two cases had completely circumscribed capsules. Two cases had duodenal invasion; one of all cases had cul de sac metastasis. Compared with 12 non-aggressive tumors, the aggressive cases had larger tumor size (more than 9 cm) with a thicker capsule (more than 2 mm). In studies to investigate the prognostic index using nucleolar organizing region (NOR), proliferating cell nuclear antigen (PCNA) and flow cytometry as well as nuclear grade and mitotic index, we could not find the useful parameter to detect the malignant potential of PCTP. In the flow cytometric analysis of cellular DNA contents, two invasive cases and the only one case of the male patient among the non-aggressive group were aneuploid. In conclusion, although it is hard to predict the prognosis by microscopic findings only, those with a thick capsule and aneuploidy tend to be related to malignant potential. 相似文献
998.
Go ITO Eizo KANEKO Terue SAKAKIBARA Yasushi TAKEUCHI Hirofumi KITAHARA Hiroshi KOBASHI Atsushi ARAKI Tadashi TOKUNAGA Jun HASEGAWA Nagaharu KOBAYASHI Kiyoshi INOUE 《Digestive endoscopy》1989,1(1):10-17
Abstract: Fasting gastric juice acidity was assessed to elucidate its role in the cause of acute gastric mucosal lesions (AGML). Gastric juice was aspirated through an auxiliary endoscopic channel during routine endoscopic examinations, and its pH was measured with a glass electrode PH meter. The pH of 100 cases with AGML (acute hemorrhagic erosions (AHE), acute gastric ulcer and acute hemorrhagic gastritis), and 586 cases with other ulcerative or inflammatory lesions were compared with the gastric juice pH in 1775 endoscopically normal subjects. The pH value was classgied into four acid groups: Hyperacidity (pH < 1.4), Normoacidity (1).5 < pH < 2.0), Hypoacidity (2).1 < pH <4.0) and Anacidity (4). 1 < pH). In cases with AHE, a signifcant hyperacidity was recognized both in the periods preceding and just after the onset. This hyperacidity was followed by signgicant anacidity, and thereafter a return to normoacidity. These pH changes coincided well with endoscopic appearances; preceding stage-hypernormacidity, black-slough stage—hyperacidity, white-slough stage-anacidity and scarring stage-;normoacidity. These results suggest that an elevation of gastric acidity etiologically relates with the formation of AGML, especially Shin. 相似文献
999.
John Yiannikas Setsuo Takatani William J. MacIntyre Ph.D. Donald A. Underwood Sebastian A. Cook Raymundo T. Go Leonard Golding Yukihiko Nose Floyd D. Loop 《European journal of nuclear medicine and molecular imaging》1986,11(10):375-380
Using pusher-plate-type artificial hearts, changes in the degree of synchrony and stroke volume were compared to phase and amplitude calculations from the first Fourier component of individual-pixel time-activity curves generated from gated radionuclide images (RNA) of these hearts. In addition, the ability of Fourier analysis to quantify paradoxical volume shifts was tested using a ventricular aneurysm model by which the Fourier amplitude was correlated to known increments of paradoxical volume. Predetermined phase-angle differences (incremental increases in asynchrony) and the mean phase-angle difference calculated from RNAs showed an agreement of -7°±4.4° (mean ±SD). A strong correlation was noted between stroke volume and Fourier amplitude (r=0.98; P<0.0001) as well as between the paradoxical volume accepted by the aneurysm and the Fourier amplitude (r=0.97; P<0.0001). The degree of asynchrony and changes in stroke volume were accurately reflected by the Fourier phase and amplitude values, respectively. In the specific case of ventricular aneurysms, the data demonstrate that using this method, the paradoxically moving areas may be localized, and the expansile volume within these regions can be quantified. 相似文献
1000.
Anna Brzozowska Tomasz Powrózek Iwona Homa-Mlak Radosław Mlak Marzanna Ciesielka Paweł Gołębiowski Teresa Małecka-Massalska 《Pathology oncology research : POR》2018,24(1):135-143
Every year, about 650 thousand new cases of Head and Neck Cancer (HNC) are diagnosed globally. Apart from surgery, radiotherapy (RTH), chemotherapy (CHT) or its combination is used in the treatment of HNC. One of the most frequent complications and, at the same time, limitations of RTH is oral mucositis (OM). Proinflammatory cytokines (including TNF-α) play a key role in the development of OM. Genetic alterations, i.e. single nucleotide polymorphisms (SNPs) within genes encoding for receptors for TNF (ie. TNFRSF1A) may change their function. The aim of this study was to investigate relationship between a polymorphism of TNFRSF1A and occurrence and severity of acute reaction after RTH for HNC patients. Data from 58 HNC patients (stages I-IV) were analyzed. All of them were irradiated using IMRT technique with doses 50-70Gy. Oral mucositis (OM) was evaluated according to RTOG/EORTC guidelines. DNA from HNC patients were isolated from whole blood and genotypes were determined by sequencing method. Patients with TT or GT genotype demonstrated higher risk of manifestation of grade 3 OM in 5th week of RTH (p=0.041; OR=9.240; 95% CI: 1.101–77.581) compared to GG carriers. Similarly, high risk of grade 3 OM in patients with T allele presence was noted in 6th week (p=0.030; OR=10.50; 95%CI:1.257–87.690) and in 7th week (p=0.008; OR=5.625; 95% CI: 1.584–19.975) of treatment compared to patients with GG homozygote. Our results indicate an association between SNP of TNFRSF1A (rs4149570) gene and risk of more severe OM related to radiation therapy for HNC patients. 相似文献