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排序方式: 共有1046条查询结果,搜索用时 15 毫秒
1.
E L Engelhardt M Sankar C Y Wu-Wang M R Thomas W R Walker J Neu 《Journal of pediatric gastroenterology and nutrition》1991,12(4):494-500
Using the neonatal piglet, the effects of dietary cholesterol deprivation on growth, intestinal enzyme activity, intestinal and hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase), and serum lipid were studied. Six litters of piglets were randomly assigned to one of two feeding regimens: restricted (800 ml of formula/24 h) versus unrestricted (1,200 ml of formula/24 h). Within litters, piglets were separated by sex, then randomly assigned to a formula containing low cholesterol (less than 2 mg/dl) or high cholesterol (145 mg/dl). Piglets were fed for 2 weeks. Male piglets in the restricted low cholesterol group gained significantly less weight per milliliter of formula than the restricted high cholesterol males. No effect was observed in the females. Microvillus membrane lactase activity was greater in males fed a high versus low cholesterol diet. Intestinal and hepatic HMG-CoA reductase activities and serum lipid profiles showed a trend toward compensation for dietary cholesterol deprivation but did not differ statistically between the cholesterol-fed versus -deprived groups. It is concluded that dietary cholesterol deprivation in the male neonatal pig causes alterations in growth, but no other statistically significant responses were detectable in this study. 相似文献
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3.
We report on an 22-month-old white girl with tetraploidy who is growing well, but who is extremely delayed in psychomotor development. When counseling parents it is important to realize that, although quite rare, tetraploid individuals can be born alive and live for at least 22 months. The implications are also relevant to prenatal diagnosis. 相似文献
4.
O. Kempski F. Staub F. V. Rosen M. Zimmer A. Neu A. Baethmann 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1988,9(1-3):109-125
The pathophysiological chain of events occurring during cerebral ischemia is still poorly understood on a molecular level. Therefore, an in vitro model to study glial swelling mechanisms, using C6 glial cells under controlled extracellular conditions, has been established. Flow cytometry serves to determine even small cell volume changes. In this report, the effects of anoxia and acidosis on glial swelling are summarized. Anoxia alone, or in combination with iodoacetate to inhibit anaerobic glycolysis, did not cause an increase of glial volume for up to 2 h. Acidification of the incubation medium below pH 6.8, on the other hand, was immediately followed by cell swelling to 115% of normal. Amiloride or the absence of bicarbonate and Na+ in the medium significantly reduced glial swelling. The data support the contention that swelling results from an activation of the Na+/H+-antiporter to control intracellular pH. It is suggested that swelling in an ischemic penumbra is promoted by this mechanism. Therapeutic approaches to control cerebral pH might be useful to protect brain tissue in cerebral ischemia. 相似文献
5.
Inclusion of satellites in an 18/21 translocation chromosome shown by ammonical-silver staining (sat-banding) in case of partial trisomy 18. 下载免费PDF全文
R L Neu C C Ortega G A Barg W Pinto Jr L I Gardner W M Howell T E Denton 《Journal of medical genetics》1976,13(6):520-522
A male infant with a partial trisomy 18 and a 46,XY, --21, t(18;21)(18qter replaced by 18q12::21 p13 replaced by 21 qter) chromosome complement is described. The translocation chromosome is of special interest because it includes the satellites of chromosome 21. This was shown by differential satellite staining with the ammoniacal-silver technique. 相似文献
6.
N. X. Chin J. W. Gu H. C. Neu 《European journal of clinical microbiology & infectious diseases》1990,9(9):685-691
The activity of the new oral cephalosporin Bay v 3522 was compared to that of six other beta-lactam agents. Bay v 3522 inhibited methicillin-susceptibleStaphylococcus aureus andStaphylococcus epidermidis at 2 µg/ml, compared to MICs of 8 µg/ml for the other cephalosporins tested. It was more active againstStreptococcus pyogenes (MIC 0.06 µg/ml) than cefuroxime, cefixime, cephalexin and cefaclor. Groups B, C and G streptococci were inhibited at 0.12 µg/ml, while the MIC90 forStreptococcus bovis and viridans streptococci was 0.5 and 2 µg/ml, respectively. The MIC90 for enterococci andListeria monocytogenes was 8 µg/ml.Clostridium perfringens was inhibited by 0.12 µg/ml, but mostBacteroides spp. were resistant. The MIC90 for beta-lactamase positiveEscherichia coli (producing primarily TEM-1) was >64 µg/ml and for beta-lactamase negative strains 16 µg/ml. The MIC90 for high-level beta-lactamase producingKlebsiella pneumoniae was >64 µg/ml versus 4 µg/ml for other isolates. The MIC90 forMoraxella catarrhalis was 2 µg/ml, forHaemophilus influenzae 1 µg/ml, and forNeisseria gonorrhoeae 4 µg/ml.Enterobacter cloacae, Citrobacter freundii, Proteus mirabilis, Providencia spp. andPseudomonas aeruginosa were resistant. Bay v 3522 was destroyed by TEM-1, SHV-1, TEM-3 and P99 beta-lactamases. 相似文献
7.
W. Queißer M. Dietrich J. Finke B. Kubanek G. Neu A. Olischläger H. Heimpel 《Journal of molecular medicine (Berlin, Germany)》1972,50(10):498-503
Zusammenfassung Bei 47 Patienten mit akuter Leukämie wurden die Ergebnisse einer voneinander unabhängigen Klassifizierung aufgrund der panoptischen Färbung einerseits und dem Ausfall cytochemischer Reaktionen andererseits (Peroxydase, PAS-Reaktion, Naphthol-AS-Acetat-Esterase) sowie das Ansprechen auf eine adäquate Induktionstherapie in den cytologisch und cytochemisch definierten Gruppen miteinander verglichen. In 42 Fällen stimmte die cytologische und cytochemische Differenzierung miteinander überein. Hinsichtlich des Ansprechens auf Therapie ergeben sich keine signifikanten Unterschiede, gleichgültig, ob man die AL nach cytologischen oder cytochemischen Kriterien gruppiert. Eine Ausnahme bildet der bei undifferenzierten AL cytochemisch charakterisierbare PAS-Typ, bei dem ein besseres Ansprechen auf Therapie als bei den Fällen ohne diagnostisch verwendbare cytochemische Aktivität wie auch bei den granulocytär differenzierten AL gefunden wurde. Hinsichtlich des Ansprechens auf Therapie verhalten sich die Erwachsenen mit PAS-Typ ähnlich günstig wie die Kinder.Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
8.
Ivana Vančurová Miroslav Flieger Jindřich Volc Milan J. Beneš Jana Novotná Jiří Neužil Vladislav Běhal 《Journal of basic microbiology》1987,27(9):529-533
Anhydrotetracycline oxygenase was purified both by affinity chromatography and by hydrophobic interaction chromatography. Molecular weight of anhydrotetracycline oxygenase was determined to be 115,000 by Sephadex G-200 gel filtration. Using preparative isoelectric focusing the isoelectric point of the enzyme was estimated to be 5.3. The enzyme showed a sensitivity to thiol-specific inhibitors. During the hydrophobic interaction purification step, the activity dropped considerably. Reactivation occurred when a heat treated crude extract was added to the reaction mixture. 相似文献
9.
Sarah Neu Humberto Vigil Jennifer A. Locke Sender Herschorn 《Canadian Urological Association journal》2021,15(3):E175
IntroductionWe aimed to evaluate the success of bladder neck injections of triamcinolone at the time of transurethral bladder neck incision (BNI) for prevention of recurrent vesicourethral anastomotic stenosis (VUAS) following prostate cancer treatment.MethodsThis is a retrospective cohort study examining patients with recurrent VUAS post-radical prostatectomy (RP) ± radiation treated with triamcinolone injections at the time of BNI. VUAS was diagnosed by symptoms followed by cystoscopy or urethrography. The outpatient procedures were done under general anesthesia. Cold knife incisions were made at the three, nine, and 12 o’clock BN positions, followed by triamcinolone injections (4 mg/mL) into the three and nine o’clock incision sites. Treatment outcomes were determined with cystoscopy.ResultsEighteen men underwent 25 procedures over a four-year period. Median age at diagnosis of VUAS was 65 (interquartile range [IQR] 61–68); median time to VUAS from RP was eight months (IQR 5–12). Fourteen patients (78%) had radiation treatment. The cohort had 128 unsuccessful VUAS treatments, with a median of five failed treatments per patient (IQR 3–10). Failed treatments included BN dilation, BNI, BN injection of mitomycin C, and urethral stent placement. Success rate after a mean of 16.3 months (standard deviation [SD] 8.1) from the time of triamcinolone injection was 83% (15/18). Six patients went on to have successful incontinence surgery. Five patients (28%) had treatment complications (bleeding, urinary tract infection, pain, and urinary extravasation). The three non-responders are stable and awaiting re-treatment with triamcinolone injection.ConclusionsTriamcinolone bladder neck injections for post-RP VUAS are a useful and safe treatment for recurrent stenosis. 相似文献
10.
The glycopeptide antibiotic, teicoplanin, is increasingly used in Europe in the treatment of Gram-positive infection. It is administered as a bolus once daily, it has little potential for nephrotoxicity, and serum monitoring is usually unnecessary. However, poor results were reported in early trials at a daily dose of 200 mg and, more recently, at 400 mg/day in monotherapy of staphylococcal endocarditis. While 400 mg (6 mg/kg day(-1)) is now standard, US trials have tried very high doses in an attempt to improve its efficacy in monotherapy of deep-seated staphylococcal sepsis. European centres continue to use 6 mg/kg day(-1) as the usual maintenance dose and 6-12 mg/kg as the loading dose. For the more difficult cases, teicoplanin is used in combination with other agents. All available published and unpublished literature was reviewed to try to solve these problems. With the exception of endocarditis, failure rates in the 84 European open studies varied more between trials than between the dosages used. In 32 European and eight US randomized trials, a dose of 6 mg/kg day(-1) of teicoplanin was effective, except in staphylococcal endocarditis if teicoplanin was used as monotherapy. In that case, 12 mg/kg day(-1) or more was needed to achieve a cure rate similar to that of vancomycin. Treatment was most successful with trough levels over 20 mg/l. However, lower doses were effective in combination with aminoglycosides, as is common in clinical practice. An open trial suggested that 12 mg/kg day(-1) was needed for treatment of septic arthritis. It is suggested that 6 mg/kg day(-1) of teicoplanin be used for all indications except staphylococcal endocarditis and septic arthritis when it should be given in a dose of 12 mg/kg day(-1) or in combination with other agents. 相似文献