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61.
62.
Background: Telemedicine is an evolving tool to increase patients’ access to subspecialty care. Since 2014, Arkansas has been utilizing telemedicine in the evaluation of patients with hand injuries. The purpose of this study is to assess the effect of this novel telemedicine system for the management of hand trauma on patient transfer. Methods: We reviewed data from the first year of the telemedicine program (2014) and compared it to data from the year prior (2013). Data collection from both years included number of hand consults and need for transfer. From the 2014 data, we also recorded the use of telemedicine, type of transfer, distance of transfer, and time to disposition. Results: During 2013 (pre-telemedicine), there were 263 hand traumas identified. In all, 191 (73%) injuries required transfer to a higher level of care, while 72 (23%) were managed locally. In the first year of the telemedicine program (2014), a total of 331 hand injuries were identified. A total of 298 (90%) resulted in telemedicine consultation with 65% (195) utilizing video encounters. After telemedicine consultation, local management was recommended for 164 injuries (55%) while transfer was recommended for 134 (45%). Using telemedicine, there was a significant decrease in the percentage of transfer for hand injuries (P < .001). Conclusions: The telemedicine program was well utilized and provided patients throughout the state with continuous access to fellowship trained hand surgeons including regions where hand subspecialty care is not available. The program resulted in a significant decrease in the number of hospital transfers for the management of acute hand trauma.  相似文献   
63.
Human cleaving pre-embryos at 2 and 3 days and cavitated pre-embryos at 5 days post-insemination have been examined for cell number and the incidence of mononucleated cells. At least 60% of polynucleate or anucleate cells have been detected at all these stages and regardless of morphological grading at day 2. It is concluded that even by the time at which pre-embryo replacement would occur therapeutically, the majority of pre-embryos are unlikely to have full developmental potential. The possible origins of the abnormalities of nucleocytoplasmic ratios are discussed.  相似文献   
64.
Objectives: To elucidate the pressure transfer between intracranial and labyrinthine fluids in patients with well‐defined unilateral Meniere's disease. Study Design: Eleven patients previously exposed to hypobaric pressure agreed to be investigated further with the tympanic membrane displacement (TMD) technique. TMD was used to indirectly analyze perilymph pressure changes as the result of changes in body position. Methods: Repeated measurements for both the diseased and the healthy ears were made with the patients supine and then in a sitting position. The TMD parameters for the maximum inward displacement, the Vi, and the mean volume displacement, the Vm, were calculated and compared. Results: The paired comparison showed statistically significant larger Vi values for both ears in the supine position. A similar tendency was observed for the Vm value. This difference of the Vi was significantly larger for the diseased ear compared with the currently healthy ear. The results were compared to the audiometric and electrocochleographic results previously obtained on the same patients when they were subjected to hypobaric pressure. Patients who experienced the largest differences in hearing level thresholds in the lower frequencies also showed the greatest differences in TMD values as the result of postural changes. Conclusions: Despite the limited number, the statistically supported results suggest a relation between the efficiency of the routes of pressure transfer and the observed effect of hypobaric exposure. The results also indicate that for the patients tested, the routes of communication are more effective in the diseased ear than in the healthy ear—a condition that may relate to the pathogeneses of Meniere's disease.  相似文献   
65.
Serum insulin-like growth factor binding protein-1 (IGFBP-1)concentrations were measured at the end of the proliferativephase in infertility patients undergoing normal menstrual cyclefrozen embryo transfer, exogenous hormone-supported frozen embryotransfer and in-vitro fertilization (IVF) treatment cycles.These patients were divided into five groups according to theirovarian follicular activity. The exogenous hormone-supportedfrozen embryo transfer group, who had no ovarian follicles,and the IVF groups (number of follicles ranging from 4–38)showed statistically higher serum IGFBP-1 concentrations whencompared to the normal menstrual cycle group (P0.01). Therewas no significant difference in the serum IGFBP-1 concentrationsbetween the exogenous hormone support frozen embryo transfergroup and the poor or normal response IVF groups (number offollicles ranging from 4 to 16). An IVF group that displayedan excessive response to our standard human menopausal gonadotrophinstimulation (>>20 mature follicles or oestradiol >>10000 pmol/1) showed a significantly higher serum IGFBP-1 concentrationwhen compared with the other groups (P = 0.001). This subgroupwas subsequently given a modified (follicle-stimulating hormone)stimulation regime which resulted in a significant reductionin serum IGFBP-1 concentrations (P << 0.05). There wasno correlation between serum oestradiol and IGFBP-1 overallor within the patient groups. We conclude that serum IGFBP-1concentrations in our down-regulated assisted conception cyclesdid not increase in line with ovarian follicular activity, unlessan excessive response was displayed.  相似文献   
66.
In this study we have investigated the effects of breath holding and of the physical properties of gases on four different respiratory dead spaces (V D): the Fowler, the physiological, the washout and the inert gas dead space. The experiments were performed with dogs which were ventilated artifically with breathing patterns with different post-inspiratory breath holding times (t a) of 0, 0.5, 1.0 and 2.0 s. Tracer amounts of acetone, ether and enflurane were infused continuously into a peripheral vein and a bolus of a mixture of krypton, Freon12 and SF6 was introduced into the peritoneal cavity. After reaching steady state, samples of arterial blood, mixed venous blood and mixed expired air were taken simultaneously. From the partial pressures (P a, P ¯V and P respectively) we determined the excretion (=P/P¯V), retention (R=Pa/P¯V) and the physiological dead space fraction (V D,phys/V T=(1 P/Pa) for each gas, where V T is tidal volume. Further, we recorded the expirograms of the six tracer gases and of CO2 from which the Fowler dead space fractions (V D,Fowler/V T) of the different gases were determined. Also the washout dead space fractions (V D,washout/V T) for He and SF6 were determined as well as the inert gas dead space fraction (V D,MIGET/V T) with the use of the multiple inert gas elimination technique (MIGET).With the exception of V D,phys/V T for SF6, all dead space fractions decreased with increasing t a. V D,phys/V T for the poorly soluble gas SF6 was considerably larger than V D,phys/V T for the remaining gases. For the highly soluble acetone V Fowler/V T was considerably smaller than V D,Fowler/V T for the other gases. V D,washout,SF6/V T was always larger than V D,washout,He/V T and V D,Fowler,SF6/V T. Further, V D,phys/V T was larger than V D,Fowler/V T for SF6 and acetone. However, for gases with intermediate solubility in blood V D,phys/V T tended to be smaller than V D,Fowler/V T. We conclude that the respiratory dead spaces are affected by the breathing pattern and by the physical properties of gases, i.e. their diffusivity in alveolar gas and their solubility in blood or lung tissue.  相似文献   
67.
Thiopental was administered to neurosurgical patients for cerebral protection and its pharmacokinetic parameters were determined after a single bolus of 540, 1000 or 1500 mg (3 subjects) or after multiple doses of 250 mg (5 subjects) and 500 mg (2 subjects) every two hours for up to 7 days. The data were analysed by a two- or three- compartment model and linear kinetics. After a single IV bolus, the mean initial volume of distribution (V1) was 0.4811·kg–1, and the steady-state volume of distribution (Vss) was 2.16 1·kg–1. The distribution (t1/2) and elimination (t1/2) half-lives were 0.590 and 5.89 h, respectively, and the mean residence time (MRT) was 7.44 h. The clearance was 5.41 ml·min–1·kg–1. With repeated injections, the pharmacokinetic parameters for each patient were estimated taking into account all administered doses and blood samples, which were taken whenever possible daily at steady state and after the last dose. The variability observed in the pharmacokinetic parameters of thiopental reflected by the coefficient of variation (CV%) was wide but was of similar magnitude within patients (CVintra) as it was between patients (CVinter). The steady-state trough plasma concentration (Cmin obs) ranged from 4.8 to 30 mg·1–1 (mean 16.0 mg·1–1 and median 14.3 mg·1–1). Peak concentrations (Cmax obs) ranged from 8.35 to 45 mg·1–1 (25.4 mg·1–1, and median 23.3 mg·1–1). The values of V1 and Vss were similar to those obtained after a single dose. For V1, the mean was 0.333 1·kg–1. The mean Vss was 2.68 1·kg–1, with a CVintra of 12.6 to 56% and a CVinter of 13.2%. A shorter distribution half-life t1/2 was noted on multiple dosing; the mean value was 0.122 h. The elimination half-life t1/2 and the mean residence time became longer due to a decrease in clearance. For t1/2 the mean value was 16.3 h. The mean MRT was 21.9 h, CVintra 9.19 to 48.5%, and the CVinter 35.3%. The mean clearance was 2.16 ml·min–1·kg–1, CVintra 7.28 to 25.5%, and the CVinter 20.4%. This value is 50% lower than after a single dose.Identification of the kinetic parameters of thiopental allows simulation of the effects of doses on subsequent plasma levels and will permit a priori prediction of day to day adjustment of drug dosage.  相似文献   
68.
Patients with polycystic ovarian syndrome (PCOS) have higher miscarriage rates. It is postulated that this is caused by a lower rate of mature oocytes, and a lower quality of embryos. Retrospectively we analysed 51 intracytoplasmic sperm injection (ICSI) cycles of 31 PCOS patients. These data were compared to age-matched controls (105 cycles) during the same period. All patients of both groups received gonadotrophin-releasing hormone (GnRH) agonists prior to gonadotrophin treatment. The rate of metaphase II oocytes (MII) was not different. However, the mean absolute number of normally fertilized oocytes was significantly higher in PCOS patients (5.00 versus 3.56, P < 0.01), due to a higher number of oocytes retrieved. More embryos were transferred by cycle in the PCOS group (2.69 versus 2.17, P < 0.05), with a higher cumulative embryo score. The overall and multiple pregnancy rate showed no differences and the clinical abortion rate was lower (21 versus 41.67%, P < 0.05) in the controls. Our findings demonstrate that negative factors unconnected to oocyte morphology must be present in PCOS patients. It is possible that only cytoplasmic, not nuclear, maturity is influenced in these patients.  相似文献   
69.
基于开发的计算机取样系统,采用SPSR法脉冲动态测试KD306型耐硫甲烷化催化剂的有效扩散系数。线性化和参数估值的结果吻合较好,证实:线性化简化是合理的,参数估值是可用于有效扩散系数。KD306型耐硫甲烷化催化剂的曲折因子为7.2。  相似文献   
70.
目的研究白血病抑制因子(LIF)在胚胎发育中的作用并探讨其参与胚泡着床的机制。方法收集昆明种小鼠的单细胞受精卵,连续培养120h,观察不同浓度LIF对胚胎发育的影响;用免疫印迹法测定培养液中细胞间粘附分子(ICAM-1的表达水平。结果LIF在0.1~10ng/ml浓度之间对胚胎发育有促进作用,其作用在桑椹胚及胚泡期最明显(P<0.05);LIF增加胚胎ICAM-1的表达,其作用在0.1ng/ml浓度时最强,并随着浓度的增加而减弱。结论适应浓度的LIF可促进胚胎发育,增加ICAM-1的表达,从而参与胚胎着床过程。  相似文献   
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