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11.
Cells are known to be surrounded by nanoscale topography in their natural extracellular environment. The cell behavior, including morphology, proliferation, and motility of bovine pulmonary artery smooth muscle cells (SMC) were studied on poly(methyl methacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) surfaces comprising nanopatterned gratings with 350 nm linewidth, 700 nm pitch, and 350 nm depth. More than 90% of the cells aligned to the gratings, and were significantly elongated compared to the SMC cultured on non-patterned surfaces. The nuclei were also elongated and aligned. Proliferation of the cells was significantly reduced on the nanopatterned surfaces. The polarization of microtubule organizing centers (MTOC), which are associated with cell migration, of SMC cultured on nanopatterned surfaces showed a preference towards the axis of cell alignment in an in vitro wound healing assay. In contrast, the MTOC of SMC on non-patterned surfaces preferentially polarized towards the wound edge. It is proposed that this nanoimprinting technology will provide a valuable platform for studies in cell-substrate interactions and for development of medical devices with nanoscale features. 相似文献
12.
Kathryn Leary Harry H. Yim Lu Bing Zhou Rose E. Sekulovich Rozanne M. Sandri-Goldin 《Virus genes》1989,3(1):57-68
To determine the role of the HSV-1 genome structure and environment on the regulation of gene expression, we constructed recombinant viruses containing a heterologous gene inserted into either the immediate early ICP0 or late glycoprotein C (gC) genes of HSV-1. The heterologous gene consisted of the SV40 early promoter (without enhancer sequences) linked to the coding sequences for the bacterial chloramphenicol acetyl transferase (CAT). The expression of CAT was examined in Vero cells infected with either virus (named ICP0-CAT and Sph 6). For both recombinants, expression of CAT was not dependent upon prior viral protein synthesis. The kinetics of expression of CAT-specific mRNA resembled that of the HSV-1 genes into which CAT was inserted. Primer extension analysis revealed that the SV40 promoter is recognized and used when placed in cis in two different HSV-1 genome locations, and Northern hybridization experiments confirmed that the heterologous gene was expressed in the absence of prior viral protein synthesis. Therefore, this gene was not regulated as strictly as an HSV-1 gene, but was influenced by the environment into which it was placed, presumably by factors that are present when the normal viral gene is on. 相似文献
13.
Previous studies demonstrated that the formamidine pesticide chlordimeform (CDM) reversibly inhibited prostaglandin biosynthesis and prevented the late (PG-mediated) phase of carrageenin-induced hind paw edema. This study emphasizes antagonism by CDM of the early (5HT and histamine-mediated) phase of carrageenin edema. CDM and cyproheptadine both antagonized paw edema induced by albumin (5HT and histamine-mediated) and by the direct injection of 5HT and histamine, whereas aspirin and the PG antagonist, SC-19220, were ineffective. As expected, cyproheptadine selectively reduced the early phase, whereas aspirin and SC-19220 selectively reduced the late phase of carrageenin-induced edema. These results are thus consistent with earlier studies demonstrating PG mediation of the late phase of carrageenin edema, and 5HT and histamine mediation of albumin edema and the early phase of carrageenin edema. In addition, they indicate that CDM possesses multiple acute anti-inflammatory, actions not exhibited by aspirin, by SC-19220 or by cyproheptadine alone. 相似文献
14.
We describe the use of suicide vectors to generate site-specific mutations in group B streptococcus. This is accomplished by cloning gene-specific sequences into a temperature sensitive plasmid and selecting for clones which have undergone homologous recombination. The recombinan clones can be easily isolated by selecting for clones which have retained the antibiotic resistance markers that are present on the vector or cloned into the gene-specific sequences. To confirm the fidelity of the recombination events, PCR analysis is performed on chromosomal DNA isolated from the recombinant clones. Using this strategy, we have generated site- specific insertions in several capsule genes and have found that these insertions occurred as expected and that the mutations result in loss of capsule expression. In this report, we specifically detail the construction of cpsB mutants by single and double cross-over recombination and demonstrate that the resulting strains are acapsular. 相似文献
15.
The1H-NMR signals of 2-cephems and 3-cephems have been assigned and the Nuclear Overhauser Effect (NOE) study of these compounds
was undertaken. 相似文献
16.
A. P. C. Yim 《Surgical endoscopy》1995,9(9):1013-1016
We prospectively studied thoracoscopic suturing of apical bullae in the management of primary spontaneous pneumothorax. From June 1993 to July 1994, we performed 29 such procedures in 27 patients. (All males ranging in age from 15 to 40.) Bullae less than 2 cm in diameter were imbricated (18), while larger bullae were resected and repaired with 3/0 polypropylene suture (11). Postoperative morbidity was minimal. Averaged postoperative parenteral narcotic (Pethidine) requirement was 88 mg, chest drainage was 1.7 (range 1–4) days, and hospital stay was 2.5 (range 1–7) days. There was no recurrence after a mean follow-up of 10 months. In comparison, 32 patients prior to this study period underwent staple resection of apical bulla. Demographic data in the two groups were similar. Averaged Pethidine requirement in the staple group was 98 mg, chest drainage was 1.8 (range 1–5) days, and hospital stay was 2.6 (range 1–7) days. There was no statistical difference in the two groups with respect to pain medication, chest drainage, or hospital stay. The technique of thoracoscopic suturing can be easily acquired. In view of the high cost of staple-cutters, endoscopic suturing should be considered as a viable alternative to staple resection of apical bullae in the treatment of primary spontaneous pneumothorax.Presented in part at the 4th World Congress of Endoscopic Surgery, Kyoto, Japan, June 16–19, 1994 [6] 相似文献
17.
N Franceschi K K Yim W C Lineaweaver P P Siko B S Alpert G M Buncke H J Buncke 《Annals of plastic surgery》1991,27(2):121-125
We reviewed our experience with 11 consecutive combined latissimus dorsi and serratus anterior free-muscle transplantations from 1980 to 1990. All 11 flaps were successful and there was minimal morbidity. This combined muscle flap is ideal for soft-tissue coverage in extensive lower extremity wounds, in mutilating hand injuries with dorsal and palmar defects, and in situations when a long vascular pedicle is needed to get out of the "zone of injury." 相似文献
18.
Pong Mo Yuen MRCOG So Fan Yim MRCOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(4):472-473
EDITORIAL COMMENT: In medicine, human judgment is fallible, but obstetrics is the discipline in which an error of judgment is most rapidly revealed, to the obstetrician, the patient and the labour ward staff, due to the unpredictability of the duration of labour and imminence of delivery in any individual patient. When the editor was a house officer he was called to the antenatal ward because a multipara, near term had abdominal pain. Vaginal examination revealed an undiluted cervix, but within the minute or so it took a walk to the handbasin to wash his hands the woman had delivered a live baby into the bed. It is always wise, and should be a routine. unless operating in haste for an emergency such as bleeding from placenta praevia, to perform a vaginal examination after anaesthesia is established before commencing Caesarean section in a woman in labour. The editor has performed many safe easy-forceps deliveries in this circumstance, in theatre, in women in whom Caesarean section was planned for cephalopelvic disproportion with or without fetal distress. This finesse is more important if the consultant has agreed to perform a Caesarean on the findings recorded by others, but the fact remains that labour and delivery can accelerate most unexpectedly. We accepted this case report for publication, not merely because it is the first such case reported, but also for the opportunity it provided to stress to readers the need for final evaluation of the stage of labour before Caesarean section, when the conditions are most favourable for assessment. Nonetheless, as this case tells us. it is possible for labour and delivery to proceed faster than the obstetrician can perform a Caesarean section. 相似文献
19.
Han DH Kwon OK Byun BJ Choi BY Choi CW Choi JU Choi SG Doh JO Han JW Jung S Kang SD Kim DJ Kim HI Kim HD Kim MC Kim SC Kim SC Kim Y Kwun BD Lee BG Lim YJ Moon JG Park HS Shin MS Song JH Suk JS Yim MB;Korean Society for Cerebrovascular Disease 《Acta neurochirurgica》2000,142(11):1263-73; discussion 1273-4
A co-operative study was conducted to determine the clinical characteristics of patients with moyamoya disease who were diagnosed and treated at neurosurgical institutes in Korea before 1995. Twenty-six hospitals contributed 505 cases and among them, the clinical characteristics of 334 patients with definite moyamoya disease were evaluated. The number of patients began to increase from the late 1980s, and after that approximately 20 patients were treated each year. There were two age peaks: from six to 15 and from 31 to 40 years of age. Haemorrhagic manifestations occurred in approximately 43% of the patients. The major clinical manifestations were haemorrhage in adults (62.4%) and ischaemia in children (61.2%). Overall 54.5% of the patients experienced decreased consciousness levels, mainly due to intracranial haemorrhage or cerebral infarction. In the patients with ischemic manifestations, the adult patients were more likely to have cerebral infarction than the pediatric patients (80% vs. 39%) and the pediatric patients were more likely to have TIA (61% vs. 25%). Thirty eight percent of the patients underwent bypass surgery and 53% of these procedures were performed bilaterally. Treatment policies, including indications for bypass surgery and commonly used drugs, were somewhat different according to the institution. Overall favorable outcome was 73%, and the most significant factor affecting poor outcome was haemorrhagic manifestation. This article describes the characteristics of 334 patients with moyamoya disease, who were diagnosed and treated at neurosurgical institutes in Korea before 1995. 相似文献
20.
Hyunah Kim Da Young Jung Seung-Hwan Lee Jae-Hyoung Cho Hyeon Woo Yim Hun-Sung Kim 《Journal of Korean medical science》2022,37(38)
BackgroundWe evaluated patients visiting a tertiary university hospital due to a diagnosis of diabetes with a goal of achieving blood glucose control and evaluated blood glucose persistence over 7 years according to the change in blood glucose evident at 3 months after the first visit.MethodsPatients treated from 2009 to 2013 were categorized into four groups according to the change in HbA1c levels during the first 3 months of follow-up (Best_group, ≥ 1.6% decrease; Better_group, 0.5–1.5% decrease; Neutral_group, maintained at −0.4% to +0.4%; Worse_group, ≥ 0.5% increase). Each patient’s blood glucose control status was then monitored for 7 years. The incidence of stroke and acute coronary syndrome during this period was confirmed.ResultsOverall, 9,776 patients were included. HbA1c values were lower in the Best_group than in the other groups at all time points (all P < 0.001). The rate of reaching targets of < 6.5% or < 7.0% HbA1c decreased over time; the rate at which the estimated glomerular filtration rate decreased to < 30 or < 60 mL/min/1.73m2 increased over time (all trends, P < 0.01).ConclusionBlood glucose control status in the first 3 months after initiating hospital care enabled estimation of the patient’s glycemic control status for the next 7 years. In cases with poor initial blood glucose control, a new or more active method of blood glucose control should be sought. 相似文献