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1.
Parupudi V J Sriram Guduru V Rao Nageshwar D Reddy 《Indian journal of gastroenterology》2006,25(1):39-41
Endoscopic clips have been used mainly for control of gastrointestinal (GI) bleeding and occasionally for closure of GI perforations. However, closure of spontaneous esophageal perforation (Boerhaave's syndrome) by clipping has not been reported. We described successful non-surgical closure of spontaneous esophageal perforation by endoscopic clipping in a patient with bilateral pyopneumothorax and septicemia. 相似文献
2.
OBJECTIVE: The purpose of this study was to evaluate a relationship between the umbilical cord thickness and cord coiling patterns during the fetal sonographic anatomic survey in the second trimester of pregnancy. METHODS: This was a prospective study of 470 patients with singleton pregnancies who had a fetal anatomic survey with recorded umbilical coiling patterns between 18 and 23 weeks' gestation. The umbilical cord thickness was assessed as an umbilical diameter at the level of the fetal abdominal cord insertion and compared with the antenatal umbilical coiling index (aUCI), calculated as a reciprocal value of the distance between a pair of umbilical cord coils. RESULTS: Three hundred twenty-one patients had adequate sonographic umbilical cord images and maternal demographic, antenatal, and labor data to meet inclusion criteria. The mean aUCI was 0.41 with 10th and 90th percentiles of 0.21 and 0.60, respectively. A total of 10.6% (34/321) and 9.3% (30/321) of patients were categorized as having hypocoiled and hypercoiled umbilical cords, respectively. The mean cord diameter +/- SD was 9.48 +/- 0.97 mm (range 7.0-12.5 mm). There was no statistically significant correlation between aUCI and umbilical cord thickness (P = .1164). CONCLUSIONS: An aUCI, or umbilical coiling pattern, does not correlate with umbilical cord thickness. It appears that a lesser amount of the umbilical supportive tissue, mainly Wharton jelly, is not related to an increased umbilical cord coiling pattern. 相似文献
3.
Dharmarajan Sriram Narasimharaghavan Srichakravarthy Tanushree R Bal Perumal Yogeeswari 《Biomedicine & Pharmacotherapy》2005,59(8):456-459
A series of nevirapine derivatives has been synthesized in an effort to enhance the spectrum of chemotherapeutic properties for the effective treatment of AIDS and AIDS-related opportunistic infections. The nevirapine derivative bearing isoniazid moiety (3a) was found to be the most potent compound with EC50 of<0.0636 microM, CC50 of>1000 microM and selectivity index of>15,723 which also exhibited 90% inhibition against Mycobacterium tuberculosis at 6.25 microg/ml. Compound 3c showed 100% inhibition against M. tuberculosis and also exhibited potent antibacterial activity against 24 pathogenic bacteria with MIC less than 1 microg/ml. 相似文献
4.
A report of a patient who developed acute suppurative parotitis while on total parenteral nutrition for small bowel fistula is presented. The importance of early detection of parotitis as a cause of fever is emphasized. Attention to oral hygiene and early resumption of oral intake, whenever possible, are to be encouraged. 相似文献
5.
Elkins MK Vittinghoff E Baranzini SE Hecht FM Sriram U Busch MP Levy JA Oksenberg JR;San Francisco Primary Infection Group 《Genes and immunity》2005,6(1):66-69
In chronically HIV infected individuals, a number of functional B cell abnormalities have been described. However, the immediate changes that occur in the B cell compartment following viral exposure and how they affect the long-term course of infection are not well understood. We report the longitudinal analysis of B cell repertoires during early infection in untreated and treated individuals receiving highly active antiretroviral therapy (HAART). Analysis was based on IgG heavy chain gene utilization and CDR3 length measurement and relationship with CD4/CD8 counts, viral load, and total serum IgG, and anti-HIV antibodies levels. Repertoires were assessed at baseline and at weeks 2, 4, 12, 24, and 72 after initiation of therapy. The findings indicate a stable peripheral B cell repertoire during the first 72 weeks following infection, particularly in the HAART treated patients. A modest association between B cell repertoire integrity and viremia levels as well as treatment was detected. 相似文献
6.
Julie A. Hides Gunda Lambrecht Christopher T. Sexton Casey Pruett Nora Petersen Patrick Jaekel André Rosenberger Guillaume Weerts 《The spine journal》2021,21(3):477-491
BACKGROUND CONTEXTOne of the primary changes in the neuromuscular system in response to microgravity is skeletal muscle atrophy, which occurs especially in muscles that maintain posture while being upright on Earth. Reduced size of paraspinal and abdominal muscles has been documented after spaceflight. Exercises are undertaken on the International Space Station (ISS) during and following space flight to remediate these effects. Understanding the adaptations which occur in trunk muscles in response to microgravity could inform the development of specific countermeasures, which may have applications for people with conditions on Earth such as low back pain (LBP).PURPOSEThe aim of this study was to examine the changes in muscle size and function of the lumbar multifidus (MF) and anterolateral abdominal muscles (1) in response to exposure to 6 months of microgravity on the ISS and (2) in response to a 15-day reconditioning program on Earth.DESIGNProspective longitudinal series.PATIENT SAMPLEData were collected from five astronauts who undertook seven long-duration missions on the ISS.OUTCOME MEASURESFor the MF muscle, measures included cross-sectional area (CSA) and linear measures to assess voluntary isometric contractions at vertebral levels L2 to L5. For the abdominal muscles, the thickness of the transversus abdominis (TrA), obliquus internus abdominis (IO) and obliquus externus abdominis (EO) muscles at rest and on contraction were measured.METHODSUltrasound imaging of trunk muscles was conducted at four timepoints (preflight, postflight, mid-reconditioning, and post reconditioning). Data were analyzed using multilevel linear models to estimate the change in muscle parameters of interest across three time periods.RESULTSBeta-coefficients (estimates of the expected change in the measure across the specified time period, adjusted for the baseline measurement) indicated that the CSA of the MF muscles decreased significantly at all lumbar vertebral levels (except L2) in response to exposure to microgravity (L3=12.6%; L4=6.1%, L5=10.3%; p<.001), and CSAs at L3-L5 vertebral levels increased in the reconditioning period (p<.001). The thickness of the TrA decreased by 34.1% (p<.017), IO decreased by 15.4% (p=.04), and the combination of anterolateral abdominal muscles decreased by 16.2% (p<.001) between pre- and postflight assessment and increased (TrA<0.008; combined p=.035) during the postreconditioning period. Results showed decreased contraction of the MF muscles at the L2 (from 12.8% to 3.4%; p=.007) and L3 (from 12.2% to 5%; p=.032) vertebral levels following exposure to microgravity which increased (L2, p=.046) after the postreconditioning period. Comparison with preflight measures indicated that there were no residual changes in muscle size and function after the postreconditioning period, apart from CSA of MF at L2, which remained 15.3% larger than preflight values (p<.001).CONCLUSIONSIn-flight exercise countermeasures mitigated, but did not completely prevent, changes in the size and function of the lumbar MF and anterolateral abdominal muscles. Many of the observed changes in size and control of the MF and abdominal muscles that occurred in response to prolonged exposure to microgravity paralleled those seen in people with LBP or exposed to prolonged bed rest on Earth. Daily individualized postflight reconditioning, which included both motor control training and weight-bearing exercises with an emphasis on retraining strength and endurance to re-establish normal postural alignment with respect to gravity, restored the decreased size and control of the MF (at the L3-L5 vertebral levels) and anterolateral abdominal muscles. Drawing parallels between changes which occur to the neuromuscular system in microgravity and which exercises best recover muscle size and function could help health professionals tailor improved interventions for terrestrial populations. Results suggested that the principles underpinning the exercises developed for astronauts following prolonged exposure to microgravity (emphasizing strength and endurance training to re-establish normal postural alignment and distribution of load with respect to gravity) can also be applied for people with chronic LBP, as the MF and anterolateral abdominal muscles were affected in similar ways in both populations. The results may also inform the development of new astronaut countermeasures targeting the MF and abdominal muscles. 相似文献
7.
Isatin and its derivatives have been reacted with 4-(4'-chlorophenyl)-6-(4"-methyl phenyl)-2-aminopyrimidine to form Schiff bases and the N-Mannich bases of these compounds were synthesized by reacting them with formaldehyde and several secondary amines. Investigation of antimicrobial activity of the compounds was made by the agar dilution method against 28 pathogenic bacteria, eight pathogenic fungi and anti-HIV activity against replication of HIV-1 (III B) in MT-4 cells. The compounds are significantly active against bacteria and fungi. 相似文献
8.
Sriram Gunda Sudharshan Hariharan Ashim K Mitra 《Journal of ocular pharmacology and therapeutics》2006,22(6):465-476
AIM: The overall aim of this study was to evaluate the corneal absorption of dipeptide monoester prodrugs of ganciclovir (GCV) and compare these results with L-valine-GCV and GCV. Another aim was to evaluate the pharmacokinetics of these prodrugs in aqueous humor. METHODS: A well was placed on the cornea of anesthetized New Zealand albino rabbits with linear probes implanted in the aqueous humor. Two hundred microlitres (200 microL) of a 0.43% w/v (saturation concentration) solution of GCV and equimolar concentrations of its prodrugs, VGCV, glycine-valine-GCV (GVGCV), valine-valine-GCV (VVGCV), and tyrosine-valine- GCV (YVGCV), were placed in the corneal well and were allowed to diffuse for a period of 2 h. Subsequently, the drug solution was aspirated and the well removed. Samples were collected every 20 min throughout the infusion and postinfusion phases and were analyzed by high-performance liquid chromatography to determine the aqueous humor concentrations. RESULTS: Area under the concentration time profile (AUC)infinity and maximum concentration (Cmax) of YVGCV were found to be higher than other prodrugs. AUC of total GCV obtained from YVGCV administration was found to be twelvefold more than AUC of GCV and 6.2-fold more than AUC obtained with total GCV from VGCV administration. VVGCV also exhibited 3.2 times higher AUC relative to VGCV. Also, AUC and Cmax of regenerated GCV from YVGCV was 8.6 and 4.9 times more than GCV, respectively. VVGCV did not produce higher concentrations of GCV. Elimination half-life of regenerated GCV from YVGCV administration was observed to be 157 min. CONCLUSIONS: YVGCV and VVGCV exhibited superior corneal absorption and bioavailability, in comparison with GVGCV, VGCV, and GCV. Such facilitated absorption of prodrugs may be a result of a combination of transcellular passive diffusion and peptide transporter (PEPT1)-mediated transport across the corneal epithelium. 相似文献
9.
10.
Neeraj Sriram MD Candidate Gary R. Hunter PhD Gordon Fisher PhD David W. Brock PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2014,16(3):172-176
Recent studies have reported a strong association between blood pressure (BP) and resting energy expenditure (REE). However, it is not known whether this relationship persists over time. Therefore, the authors examined the temporal relationship between REE and systolic BP. In addition, the impact of sympathetic tone and anthropometric variables on this relationship was examined. All testing was performed on healthy, overweight African American and European American women aged 25 to 45 years over 4.5 years in the University of Alabama at Birmingham General Clinical Research Center. Repeated‐measures mixed‐models revealed REE as a significant determinant of systolic BP (β=0.0155, P<.0001), independent of catecholamines, leg fat, visceral fat, fat‐free mass, fat mass, height, relative skeletal muscle index, and resting heart rate. Observations that REE is predictive of systolic BP across 4.5 years support previous findings that REE may potentially mediate resting BP, independent of anthropometric variables and a marker for sympathetic tone. 相似文献