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801.
Elaiophylin (1) and two new methyl derivatives, 11-O-monomethylelaiophylin (2) and 11,11'-O-dimethylelaiophylin (3), were isolated from the mycelium cake of Streptomyces strains HKI-0113 and HKI-0114. The structures of 2 and 3 were determined by mass spectrometric and NMR investigations. Compounds 2 and 3 display antimicrobial and moderate cytotoxic activities. 相似文献
802.
Cells normally have five options. These include renewal or proliferation, terminal differentiation, quiescence, senescence, and apoptosis. Many factors interact with cell cycle regulators to direct the cells toward these different options. Tumor suppressor genes play a pivotal role in this process. Alterations in these genes may limit the options that cells have and thus play a significant role in the multistep process of carcinogenesis. We will focus on tumor suppressor genes and especially tumor suppressor genes that interact directly with the cell cycle proteins. 相似文献
803.
We present a case of a 50-year-old female evaluated for a 1-year history of numbness of the first and second toe of the right foot. Echocardiography performed in order to exclude cardiovascular compromise revealed a granular mass originating from the posterior part of the interatrial septum. On subsequent magnetic resonance imaging (MRI) with fat suppression sequences, the final diagnosis of lipomatous hypertrophy of the interatrial septum, a benign and underrecognized condition characterized by septal accumulation of fatty tissue, was made. Although no previous reports have focused on this, tailored cardiac MR with fat suppression sequences proved to be an excellent noninvasive method in assessing an accurate diagnosis and in differentiating lipomatous hypertrophy of the atrial septum from other cardiac neoplasms. 相似文献
804.
WF Knaus DH Beermann TF Robinson DG Fox KD Finnerty 《Canadian Metallurgical Quarterly》1998,76(5):1481-1487
Our objective was to determine to what extent rate and efficiency of protein gain in finishing cattle can be enhanced by feeding an amino acid-balanced mixture of undegraded intake proteins. The Cornell Net Carbohydrate and Protein System (CNCPS) model was used to formulate a corn-based diet that would meet the rumen requirements for 410-kg large-framed steers with an estrogen implant and fed an ionophore. The CNCPS model was also used to formulate a highly undegradable intake protein (UIP) mixture from meat and bone meal, blood meal, fish meal, and hydrolyzed feather meal to provide the amino acids needed to supplement those derived from microbial protein to better meet amino acid requirements for growth. Four Holstein steers weighing 407 kg were offered a 90:10 concentrate-forage diet at hourly intervals at 95% of ad libitum intake. The steers were injected with 500 microg of estradiol-17beta at 12-h intervals to mimic the effects of an estrogenic implant. Treatments planned consisted of inclusion of the UIP mixture at 0, 2.5, 5, and 7.5% of the diet DM. Dry matter intake was fixed at 6.4 kg/d, and DM digestibility was not significantly affected by varying the amount of UIP addition. Apparent digestibility of N increased (P = .011) from 63.8 to 65.8, 70.7, and 71.5%, the amount of N absorbed increased (P = .001) from 73 to 84, 100, and 106 g/d, and N balance increased (P = .003) from 20 to 30, 33, and 39 g/d when UIP was fed at 0, 2.6, 5.2, and 7.8% of diet DM, respectively. The efficiency of N use increased 39.7%, and biological value increased 31.6% when the UIP mixture was added to the diet. Circulating concentrations of plasma urea N (PUN) were increased (P = .017) from 4.5 for the control diet to 5.7, 6.2, and 6.1 mg/dL when the UIP mixture was added at 2.6, 5.2, and 7.8%, respectively. Corresponding IGF-I concentrations were also increased from 491 to 558 and 624 ng/mL with 2.6 and 5.2% levels of UIP addition. Plasma glucose, NEFA, and insulin concentrations were not affected by feeding the UIP mix. The rate and efficiency of N use for growth improved with addition of an amino acid-balanced UIP mixture to the diet. 相似文献
805.
806.
HH Kuper MA van Leeuwen PL van Riel ML Prevoo PM Houtman WF Lolkema MH van Rijswijk 《Canadian Metallurgical Quarterly》1997,36(8):855-860
An assessment of the onset of radiographic damage in the large joints (hip, knees, shoulders, elbows, ankles and tarsus) in patients with early rheumatoid arthritis, and the relationship of the progression of large joint damage with joint damage in hands and feet, with physical disability, and with cumulative disease activity, was performed in a prospective 6 yr follow-up study. Large joint damage appeared to be an early phenomenon with 20% of the patients having some damage in at least one large joint within 1 yr, and 50% of the patients within 6 yr after disease onset. Radiographic damage in large joints was significantly related to the damage in hands and feet, the physical disability index, and the cumulative disease activity. The initial disease activity at study entry was the only prognostic factor that reached significance. 相似文献
807.
Parascalene block is a technique of blocking the brachial plexus at the lateral border of the anterior scalene muscle superior to the clavicle. The objective of this study was to define the position of the needle in parascalene block with relationship to the brachial plexus and the dome of the pleura, which is important in determining whether this technique minimizes the incidence of pneumothorax. In the first group, 10 patients scheduled for minor upper extremity surgery agreed to parascalene block, which was performed in the computed tomographic examination room. In the second group, 10 volunteers agreed to have markers placed at the point where a needle would be inserted for parascalene block. The computed tomographic study at the level of the needle insertion or the marker revealed that this level was superior to the dome of the pleura. The distances from the skin to the interscalene groove and the interscalene groove to the first rib at the level of the needle insertion or the marker in both groups were measured to be 17 +/- 4 mm and 15 +/- 3 mm, respectively. This study suggests that the level of the parascalene needle entry is superior to the dome of the pleura. At this level, the incidence of pneumothorax should be minimized. 相似文献
808.
GB Thompson CS Grant JA van Heerden RT Schlinkert WF Young DR Farley DM Ilstrup 《Canadian Metallurgical Quarterly》1997,122(6):1132-1136
BACKGROUND: Few controlled studies have compared laparoscopic transabdominal adrenalectomy (LA) to conventional open posterior adrenalectomy (PA). METHODS: Five patients have undergone successful LA at our institution between 1992 and 1996. A matched case-control study of 50 PA patients was performed during a similar time period. RESULTS: Follow-up was complete in 82% of patients with a mean follow-up time of 25 months. There were no statistically significant differences between the LA and PA groups with regard to the following demographic features: age, gender, endocrine disorder, side and size of tumor, and body habitus. Statistically significant differences (p < 0.05), however, were present (LA vs PA) when we compared the following results: mean hospital stay (3.1 versus 5.7 days), narcotic equivalents (28 versus 48), return to normal activity (3.8 versus 7 weeks), patient satisfaction (9 versus 7 [scale 1 to 10, 10 being most satisfied]), late morbidity (0 versus 54%), and operating room time (167 versus 127 minutes). Median hospital charges ($7,000 versus $6,000) were slightly higher in the LA group (p = 0.05). CONCLUSIONS: Although LA is technically more demanding and slightly more expensive to perform, advances appear to exist for LA with regard to patient comfort, patient satisfaction, hospital stay, and return to normal daily activities. Late incisional complications are dramatically less in the LA group. 相似文献
809.
DJ Fink PL Poliani T Oligino DM Krisky WF Goins JC Glorioso 《Canadian Metallurgical Quarterly》1997,144(1):103-121
The restricted pattern of neurodegeneration seen in Parkinson's disease, and the identification of trophic factors that prevent toxin-induced degeneration of dopaminergic neurons, has spurred research into potential gene therapy for this disease. Herpes simplex virus (HSV-1) is a neurotrophic virus which naturally establishes latency in neurons. HSV-based vectors have been demonstrated to transfer and transiently express transgenes in neurons in brain in vivo. Recent experiment have shown that deletion of multiple immediate-early HSV genes reduces the potential cytotoxicity of these vectors, and in addition results in altered patterns of transgene expression that may allow for long-term expression required for human gene therapy applications. 相似文献
810.