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排序方式: 共有1097条查询结果,搜索用时 15 毫秒
1.
Aaron Pitzele Mohammad Rahimi Eric Armbrecht 《The journal of maternal-fetal & neonatal medicine》2015,28(15):1770-1773
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion. 相似文献
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Healthcare information systems (HISs) are often implemented to enhance the quality of care and the degree to which it is patient-centered,
as well as to improve the efficiency and safety of services. However, the outcomes of HIS implementations have not met expectations.
We set out to organize the knowledge gained in qualitative studies performed in association with HIS implementations and to
use this knowledge to outline an updated structure for implementation planning. A multi-disciplinary team performed the analyses
in order to cover as many aspects of the primary studies as possible. We found that merely implementing an HIS will not automatically
increase organizational efficiency. Strategic, tactical, and operational actions have to be taken into consideration, including
management involvement, integration in healthcare workflow, establishing compatibility between software and hardware and,
most importantly, user involvement, education and training. The results should be interpreted as a high-order scheme, and
not a predictive theory. 相似文献
5.
INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
6.
Marcos Daccarett MD Gustavo Espinosa MD FACR Fred Rahimi DPM Christopher M. Eckerman DPM Shelley Wayne-Bruton DPM Mark Couture DPM Jason Rosenblum DPM 《The Journal of foot and ankle surgery》2002,41(6):372-378
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma. 相似文献
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Jennifer C. Chen Katrina L. Schmid Brian Brown Marion H. Edwards Bibianna SY Yu John KF Lew 《Clinical & experimental optometry》2003,86(5):323-330
Purpose: Caucasian children with myopia have elevated response accommodative vergence to accommodation (AC/A) ratios. The purpose of this study was twofold: to determine if response AC/A ratios vary with refractive error and with myopic progression rate in Hong Kong Chinese children, and to determine the effect of beta‐adrenergic antagonism with topical timolol application on AC/A ratios. Methods: Thirty children aged eight to 12 years participated in the study. All refractive errors were corrected with spectacle lenses. Accommodative responses were measured using a Shin‐Nippon autorefractor and concurrent changes in vergence were assessed using a vertical prism and a Howell‐Dwyer card at three metres and 0.33 metre. Accommodative demand was altered using plus or minus two dioptre lenses and lens‐ and distance‐induced response AC/A ratios were calculated. Measurements were repeated 30 minutes after the instillation of topical timolol maleate (0.5 per cent). Results: AC/A ratios appeared higher in progressing myopic children but the difference was not statistically significant. Timolol application reduced accommodative convergence (AC) in the stable myopes (reduction = ‐3 ± 1.14A) but not in the emmetropes (0.69 ± 0.9P) or progressing myopes (0.16 ± 0.43A) and this difference between refractive groups was statistically s ignificant (F2,27= 3.766; P= 0.036). However, timolol did not produce a significant change in the accommodative response to positive or negative lenses or response AC/A ratios. Conclusions: We did not find that AC/A ratios in myopic Chinese children were elevated and therefore, it is unlikely that elevated AC/A ratios are responsible for the high levels of myopia that occur in Hong Kong. The finding that timolol reduced AC in the stable myopes suggests that the autonomic control of accommodative convergence in these children may be different from that in emmetropic children and those with progressing myopia. 相似文献
9.
Nociceptin/orphanin FQ (N/OFQ), the endogenous ligand of the opioid receptor-like receptor or nociceptin receptor (NOP), has been shown to induce feeding, locomotion, anti-stress and anxiolytic effects in rodents after central nervous system injection. In this study, the effect of intracerebroventricular (icv) injection of N/OFQ on feeding and locomotion behavior was evaluated in male broiler-type chickens. The icv injection of N/OFQ caused a moderate but significant increase in feed intake similar to the classical opioid peptides in rats. It also increased feed pecking frequency and feeding time 1 h after injection. Stepping, wing flapping and preening were not affected by N/OFQ. These results suggest that N/OFQ can act within the central nervous system of chickens to increase feed intake. 相似文献
10.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献