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排序方式: 共有418条查询结果,搜索用时 1 毫秒
101.
Moacyr S Junior Luci Correa Alexandre R Marra Luis FA Camargo Carlos AP Pereira 《BMC infectious diseases》2007,7(1):88
Background
Vancomycin use is considered inappropriate in most hospitals. A particular concern is the recent emergence of S. aureus with decreased susceptibility to vancomycin, making it important to reduce overall exposure to vancomycin to minimize the incidence of VRE (vancomycin-resistant enterococci). The aim of this work was to analyze the use of vancomycin and the risk factors associated with inappropriate treatment. 相似文献102.
去氢甲基睾丸素的合成工艺研究 总被引:2,自引:0,他引:2
目的 :研究蛋白同化激素去氢甲基睾丸素的合成工艺。方法 :以去氢表雄酮醋酸酯为原料 ,经格氏反应 ,水解 ,沃氏氧化 ,DDQ脱氢等四步反应制得。结果 :该合成路线不仅收率高 ,产品纯 ,而且无需过柱分离。结论 :该工艺路线适合工业化生产。 相似文献
103.
异型缝隙连接通道和磷酸化对心脏缝隙连接的调变 总被引:5,自引:0,他引:5
目的 检测由缝隙连接蛋白(connexin,Cx)43和Cx45组成的多种异型缝隙连接通道(her—eromultimeric gap junction channels,HGJC)和磷酸化对缝隙连接(gap junction,GJ)的调变作用。方法 将转染了编码为Cx43或Cx45的DNA后的Hela细胞放置在一起共同培养组成双侧和单侧异型GJ通道。显微注射若丹明123(rhodamine123,Rh)检测经200nmol/L十四(烷)酰佛波醇乙酸酯(12-0-tetrade—canoylphorbol-13-acetae,TPA)处理前后,在紫外光显示下由Cx43和Cx45所组成的不同GJ通道对荧光染料的偶联率(coupling ratio)。结果 在不同的GJ中,同型GJ通道Cx43(homotypie Cx43,HoCx43)偶联率最高。从Cx45侧注入荧光染料的单侧异型GJ通道45(mono-heteromeric Cx45-Cx43/45,MH45)偶联率较之从Cx43/45侧注入荧光染料的MH45、双侧异型GJ通道Cx43/45(bi-heteromeric Cx43/45,BH43/45)及同型GJ通道Cx45(homotypic Cx45,HoCx45)等的偶联率是最低的。根据HoCx43或HoCx45通道的偶联率对各型通道偶联率进行标准化处理。BH43/45和MH43通道的偶联率均较HoCx43降低。对MH45通道来说,从Cx43/45侧注射的通道偶联率大于从Cx45侧注射的偶联率。TPA处理后HoCx43的偶联率降低,而当Cx43和Cx45组合成BH43/45和MH43通道后其偶联率下降更显著。结论 Cx43和Cx45共同表达可构成BH43/45、MH43和MH45等异型通道,而这些通道可降低细胞间的通讯并对磷酸化的作用不敏感。单侧异型GJ通道的偶联率取决于染料注射的方向。 相似文献
104.
A 22-year-old male patient underwent a segmental resection of the ileum due to clinical symptoms of bowel obstruction and radiological evidence of ileal wall thickening and enlarged mesenteric nodes. Histopathological examination of the resected specimen revealed an extranodal marginal zone B-cell lymphoma(MALToma) of the intestine and tuberculous lesions along with a solitary Peutz-Jeghers polyp. The case is presented for its rarity and to stress upon the clinical and radiological challenges that arise when lymphomas and tuberculous lesions co-exist at the same site.KEY WORDS: Intestinal lymphoma, MALToma, marginal zone lymphoma, Peutz-Jeghers polyp, tuberculosis 相似文献
105.
Alistair AP Slesser Sufian Sultan Faris Kubba David P Sellu 《World journal of emergency surgery : WJES》2010,5(1):27
Background
Endometriosis is a benign condition affecting females of reproductive age. Although intestinal endometriosis is common it is rare for the condition to manifest as an acute bowel obstruction secondary to ileocaecal and appendicular endometriosis. This case is important to report as it highlights the diagnostic difficulty this particular condition presents to an emergency surgeon. 相似文献106.
AP Schmidt AE B?hmer C Antunes C Schallenberger LO Porciúncula E Elisabetsky DR Lara DO Souza 《British journal of pharmacology》2009,156(1):163-172
Background and purpose
Allopurinol is a potent inhibitor of the enzyme xanthine oxidase, used primarily in the treatment of hyperuricemia and gout. It is well known that purines exert multiple effects on pain transmission. We hypothesized that the inhibition of xanthine oxidase by allopurinol, thereby reducing purine degradation, could be a valid strategy to enhance purinergic activity. The aim of this study was to investigate the anti-nociceptive profile of allopurinol on chemical and thermal pain models in mice.Experimental approach
Mice received an intraperitoneal (i.p.) injection of vehicle (Tween 10%) or allopurinol (10–400 mg kg−1). Anti-nociceptive effects were measured with intraplantar capsaicin, intraplantar glutamate, tail-flick or hot-plate tests.Key results
Allopurinol presented dose-dependent anti-nociceptive effects in all models. The opioid antagonist naloxone did not affect these anti-nociceptive effects. The non-selective adenosine-receptor antagonist caffeine and the selective A1 adenosine-receptor antagonist, DPCPX, but not the selective A2A adenosine-receptor antagonist, , completely prevented allopurinol-induced anti-nociception. No obvious motor deficits were produced by allopurinol, at doses up to 200 mg kg−1. Allopurinol also caused an increase in cerebrospinal fluid levels of purines, including the nucleosides adenosine and guanosine, and decreased cerebrospinal fluid concentration of uric acid. SCH58261Conclusions and implications
Allopurinol-induced anti-nociception may be related to adenosine accumulation. Allopurinol is an old and extensively used compound and seems to be well tolerated with no obvious central nervous system toxic effects at high doses. This drug may be useful to treat pain syndromes in humans. 相似文献107.
ANNEMARIE M VISSER VINCENT WV JADDOE LIDIA R ARENDS HENNING TIEMEIER ALBERT HOFMAN HENRIETTE A MOLL ERIC AP STEEGERS MONIQUE MB BRETELER WILLEM FM ARTS 《Developmental medicine and child neurology》2010,52(11):1014-1020
Aim To examine the incidence of paroxysmal epileptic and non‐epileptic disorders and the associated prenatal and perinatal factors that might predict them in the first year of life in a population‐based cohort. Method This study was embedded in the Generation R Study, a population‐based prospective cohort study from early fetal life onwards. Information about the occurrence of paroxysmal events, defined as suddenly occurring episodes with an altered consciousness, altered behaviour, involuntary movements, altered muscle tone, and/or a changed breathing pattern, was collected by questionnaires at the ages of 2, 6, and 12 months. Information on possible prenatal and perinatal determinants was obtained by measurements and questionnaires during pregnancy and after birth. Results Information about paroxysmal events in the first year of life was available in 2860 participants (1410 males, 1450 females). We found an incidence of paroxysmal disorders of 8.9% (n=255) in the first year of life. Of these participants, 17 were diagnosed with febrile seizures and two with epilepsy. Non‐epileptic events included physiological events, apnoeic spells, loss of consciousness by causes other than epileptic seizures or apnoeic spells, parasomnias, and other events. Preterm birth (p<0.001) and low Apgar score at 1 minute (p<0.05) were significantly associated with paroxysmal disorders in the first year of life. Continued maternal smoking during pregnancy and preterm birth were significantly associated with febrile seizures in the first year of life (p<0.05). Interpretation Paroxysmal disorders are frequent in infancy. They are associated with preterm birth and a low Apgar score. Epileptic seizures only form a minority of the paroxysmal events in infancy. In this study, children whose mothers continued smoking during pregnancy had a higher reported incidence of febrile seizures in the first year of life. These findings may generate various hypotheses for further investigations. 相似文献
108.
109.
JENS HENRICHS JACQUELINE J SCHENK CHARLOTTE S BARENDREGT HENK G SCHMIDT ERIC AP STEEGERS ALBERT HOFMAN VINCENT WV JADDOE HENRIETTE A MOLL FRANK C VERHULST HENNING TIEMEIER 《Developmental medicine and child neurology》2010,52(7):644-651
Aim The aim of this study was to investigate within a population‐based cohort of 4384 infants (2182 males, 2202 females) whether fetal growth from early pregnancy onwards is related to infant development and whether this potential relationship is independent of postnatal growth. Method Ultrasound measurements were performed in early, mid‐, and late pregnancy. Estimated fetal weight was calculated using head and abdominal circumference and femur length. Infant development was measured with the Minnesota Infant Development Inventory at 12 months (SD 1.1mo, range 10–17mo). Information on postnatal head size and body weight at 7 months was obtained from medical records. Results After adjusting for potential confounders and for postnatal growth, faster fetal weight gain from mid‐ to late pregnancy predicted a reduced risk of delayed social development (odds ratio [OR] 0.82; 95% confidence interval [CI] 0.71–0.95, p=0.008), self‐help abilities (OR 0.84; 95% CI 0.73–0.98, p=0.023), and overall infant development (OR 0.65; 95% CI 0.49–0.87, p=0.003). Similar findings were observed for fetal head growth from mid‐ to late pregnancy. Interpretation Faster fetal growth predicts a lower risk of delayed infant development independent of postnatal growth. These results suggest that reduced fetal growth between mid‐ and late pregnancy may determine subsequent developmental outcomes. 相似文献
110.
AB Kimball A Guérin M Tsaneva AP Yu EQ Wu SR Gupta Y Bao PM Mulani 《Journal of the European Academy of Dermatology and Venereology》2011,25(2):157-163
Background Psoriasis is frequently associated with comorbidities. Objective To estimate the incremental economic burden associated with comorbidities in patients with psoriasis, accounting for psoriasis severity. Methods Patients continuously enrolled ≥ 6 months after a randomly selected psoriasis diagnosis date were selected from the Ingenix Impact National Managed Care Database (1999–2004). Comorbidities identified during the 6‐month study included: psoriatic arthritis, cardiovascular disease, depression, diabetes, hyperlipidemia, hypertension, obesity, cerebrovascular diseases and peripheral vascular disease. Resource utilization and costs during the 6‐month follow‐up period were compared for patients with ≥ 1 comorbidity vs. those without and for patients with a specific comorbidity vs. those without. Adjusted incidence rate ratios (IRRs) and odds ratios (ORs) were estimated for resource utilization using negative binomial and logistic regression models, respectively. Adjusted incremental costs associated with comorbidities were reported using general linear models with log‐link and gamma distributions or two‐part models. Models controlled for age, sex and psoriasis severity. Results A total of 114 512 patients were included; 51% had ≥ 1 comorbidity. Hyperlipidemia (27%) and hypertension (25%) were most prevalent. Patients with comorbidities were more likely to experience urgent care [OR (95% confidence interval (CI)) = 1.58 (1.51–1.65)] than patients without comorbidities. They also had significantly greater hospitalization rates [IRR (95% CI) = 2.27 (2.13–2.42)] and outpatient visits [IRR (95% CI) = 1.53 (1.52–1.55)]. Compared with patients who did not have comorbidities, patients with comorbidities incurred $2184 (P < 0.001) greater total costs. Conclusion Comorbidities present a significant economic burden in patients with psoriasis. 相似文献