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11.
Cardiac pacing in children has undergone many improvements in the last decade. The differences between adult and pediatric pacing have narrowed. Children are no longer being denied pacemakers because of size. This article discusses techniques for pacing pediatric patients successfully that will allow them to lead normal lives. 相似文献
12.
The periodontal disease syndromes present the practitioner with an extensive array of clinical conditions. However, by performing a careful examination and recording of findings, the clinician will provide order to this seemingly complex picture. This careful and reasoned approach is based on a logical sequence starting with clinical observations that lead to a diagnosis of the disease entity present. This correct diagnosis in turn will lead to establishment of the prognosis and the therapeutic approach. By following these precepts, the practitioner ensures a sound biologic basis for his or her efforts. The end result is the realization of the goal of dental therapy that her is for the patient to maintain dentition in health, comfort, and function for a lifetime and minimize the potential for urgent periodontal needs. 相似文献
13.
A rapid microagglutination test for the diagnosis of Legionella pneumophila (serogroup 1) infection 总被引:4,自引:3,他引:4
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A rapid microagglutination test has been developed which can be performed in 30 minutes. Ninety-seven percent of 96 patients diagnosed as having Legionella pneumophila (serogroup 1) infection by indirect immunofluorescence were also detected by the rapid microagglutination test. 相似文献
14.
Studies on the origin of redox enzymes in seminal plasma and their relationship with results of in-vitro fertilization 总被引:3,自引:0,他引:3
Yeung CH; Cooper TG; De Geyter M; De Geyter C; Rolf C; Kamischke A; Nieschlag E 《Molecular human reproduction》1998,4(9):835-839
Glutathione (GSH), GSH peroxidase (GPX), GSH reductase (GRD), superoxide
dismutase (SOD) and catalase-like enzyme activity were quantified in
seminal plasma from normozoospermic patients, men with known distal ductal
occlusion, proven fathers and male partners of couples receiving in-vitro
fertilization (IVF) treatment for both male and female causes. Glutathione
was non-detectable (< 2.5 microM) in seminal plasma. None of the enzyme
activities per unit volume were lower in semen from vasectomized men,
suggesting that they did not originate substantially from the testis or
epididymis. The strongest relationships between enzyme activities and
accessory gland markers were between zinc and GRD (r = 0.678), SOD (r =
0.602) and GPX (r = 0.548), suggesting a largely prostatic origin of these
enzymes. Only weak relationships between accessory gland markers and
catalase-like activity suggested a multi-glandular source of this enzyme.
There was no relationship between the activity of any of the enzymes in the
IVF patients with their fertilization rates in vitro or the establishment
of pregnancy after IVF. Nor was there any correlation of enzyme activity
with the morphology and percentage of motile spermatozoa in semen or with
the percentage motility of spermatozoa immediately after swim-up or after
overnight incubation. These findings suggest that the protective enzymes in
the seminal plasma are contributed largely by the prostate and little by
the epididymis, and that in most cases of IVF, they have no major influence
on the outcome.
相似文献
15.
1. Iontophoretic injection of adenosine 3',5'-cyclic monophosphate (cAMP) into identified neurons elicited a slow transient Na+ current whose amplitude and duration were sensitive to altered intracellular pH (pHi), calmodulin blocking drugs, depolarization, and manipulations of internal and external Ca2+. 2. Intracellular acidification between resting pHi to several tenths of a pH unit increased the amplitude of the cAMP-stimulated current and prolonged its duration. 3. Intracellular alkalinization of similar magnitude also increased the amplitude and duration of the current response. The effects of alkalinization were somewhat labile. In cells alkalinized by NH4+-containing salines, washout of NH4+ with normal saline caused acidification and further enhanced the cAMP current response. The immediacy of the increase and the dual acid/basic sensitivity of the response suggest an accommodative process whereby the responsiveness of the cell to cAMP adapts to a maintained pHi. 4. The calmodulin blockers trifluoperazine and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide increased the amplitude and duration of the current response. Phorbol ester activators of Ca2+/phospholipid-dependent kinase had no effect on the current. 5. Periods of depolarization preceding tests significantly reduced current response amplitude. This effect was dependent on saline Ca2+ and was blocked by Co2+. 6. Intracellular injection of the Ca2+ chelator ethylene glycol-bis(beta-aminoethyl ether)N,N,N',N',-tetraacetic acid also augmented the amplitude and duration of the current response. 7. The above effects are consistent with a possible common site of action on cAMP degradation. This interpretation is consistent with previous evidence for pH-sensitive and Ca2+/calmodulin-dependent cAMP phosphodiesterase activity in Pleurobranchaea nervous tissue. 相似文献
16.
Gillette TM Holland GJ Vincent WJ Loy SF 《The Journal of orthopaedic and sports physical therapy》1991,13(3):126-131
This study examined the effects of submaximal, treadmill exercise-induced body core temperature (BCT) increase on selected knee range of motion (ROM). Twenty males, 18-35 years old, were tested (randomized crossover) for ROM, BCT, and heart rate (HR), followed by either Treatment I (20 minutes of rest) or Treatment II (20 minutes of submaximal running). The two treatments were subsequently followed by a two-minute passive stretch. Range of motion was assessed before and after passive stretch treatment intervention. Treatment means differed for BCT and HR (p < 0.001) but not for ROM after exercise intervention. It was concluded that 20 minutes of exercise increased BCT (>1 degrees C) but had no effect on knee ROM. J Orthop Sports Phys Ther 1991;13(3):126-131. 相似文献
17.
18.
D.E. Miga L.F. McKellar S. Denslow H.B. Wiles C.L. Case P.C. Gillette 《Pediatric cardiology》1997,18(3):204-207
Catheter ablation in children requires placement of multiple large femoral venous sheaths and catheters. Magnetic resonance
angiography (MRA) was used to evaluate the effect of indwelling lines on femoral venous blood flow. Between October 1993 and
February 1994 a total of 17 patients scheduled for catheter ablation underwent venous MRA. Two-dimensional time-of-flight
MRA was performed 12–70 hours after catheterization on all patients. All patients received intravenous heparin during the
procedure and had aspirin therapy instituted after ablation. Eighteen catheter ablations and MRA studies were performed on
the 17 patients (one patient underwent repeat ablation). There were 7 females and 10 males, with a mean age of 14.8 ± 4.2
years (range 8–21 years). Patients had three venous sheaths inserted in the left femoral vein (5F, 6F, and 7F with external
diameters measuring 1.7, 2.0, and 2.3 mm, respectively) and one sheath in the right femoral vein (7F). Four patients (22%)
had altered venous flow (two complete obstructions and two partial obstructions) following catheterization. None of these
patients experienced symptoms or complications. It was concluded that there is an increased incidence (22%) of venous obstruction
following catheter ablation, but there are no related complications. Venous MRA provides a rapid, noninvasive method for evaluating
venous flow abnormalities and possibly detects patients at risk for complications. 相似文献
19.
20.
Electro‐optic probe for real‐time assessments of RF electric field produced in an MRI scanner: Feasibility tests at 3 and 4.7 T
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Isabelle Saniour Gwenaël Gaborit Anne‐Laure Perrier Laurane Gillette Guillaume Revillod Raphaël Sablong Lionel Duvillaret Olivier Beuf 《NMR in biomedicine》2018,31(1)
During magnetic resonance imaging (MRI) examinations, the average specific absorption rate (SAR) of the whole body is calculated as an index of global energy deposition in biological tissue without taking into account the presence of metallic implants or conductive materials. However, this global SAR calculation is not sufficient to ensure patient safety and a local SAR measurement should be carried out. Several measurement techniques have already been used to evaluate the local SAR, in particular electric field (E‐field) probes, but the accuracy of the measurements and the resolutions (spatial and temporal) depend strongly on the measurement method/probe. This work presents an MR‐compatible, subcentimeter probe based on an electro‐optic (EO) principle enabling a real‐time measurement of the local E‐field during MRI scans. The experiments using these probes were performed on two different MR systems (preclinical and clinical) having different static magnetic field strengths and with different volume coil geometries. The E‐field was measured with unloaded (in air) and loaded volume coils in order to assess the sensing characteristics of the optical probe. The results show an excellent linearity between the measured E‐field and the radiofrequency (RF) magnetic field in both experimental conditions. Moreover, the distribution of the E‐field throughout the volume coil was experimentally determined and was in good agreement with numerical simulations. Finally, we demonstrate through our measurements that the E‐field depends strongly on the dielectric properties of the medium. 相似文献