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61.
The records of 191 patients involved in 316 treatment cycles over 3 years in an in vitro fertilization-embryo transfer program were reviewed. Follicular aspiration, oocyte retrieval, pregnancy rates, technical difficulty, and complications were compared in four oocyte retrieval methods: 117 laparoscopic retrievals, 116 ultrasound (US)-guided percutaneous transvesical retrievals, 43 US-guided transvaginal retrievals, and 40 combined US and laparoscopic retrievals. The mean number of aspirated follicles (9.14) was greatest in the transvaginal retrieval group, but the ratio of oocytes to punctured follicles was not statistically greater in any of the groups. The overall clinical pregnancy rate per cycle was highest in the transvaginal retrieval group: 12 of 43 cycles resulted in pregnancy, or 27.9%. The number of delivered babies (16.3%) was also highest in the transvaginal retrieval group. US-guided transvaginal oocyte retrieval is recommended as the method of choice.  相似文献   
62.
Percutaneous transluminal renal angioplasty: initial and long-term results   总被引:2,自引:0,他引:2  
Renal artery stenosis in 201 patients with hypertension was treated with percutaneous transluminal renal angioplasty (PTRA). A total of 213 procedures were performed as treatment of 262 separate stenosis. The stenosis was caused by atherosclerosis in 134 cases and by fibromuscular dysplasia (FMD) in 52 cases; the cause was indeterminate in 27 cases. Of the 213 procedures, 172 were successful or resulted in improvement, for a technical success rate of 80.8%. The initial clinical results could be evaluated in 210 cases; cure or improvement was achieved in 80%. There were 23 cases in which neither technical nor clinical success was achieved. Data on the remaining 187 cases were the basis of this long-term follow-up study. The cumulative patency rate at 5 years was 80% in the atherosclerosis group, 89% in the FMD group, and 74% in the indeterminate group. The mortality was less than 1%. Because spasm occurred in 33 cases, causing an infarction in ten instances, antispasmodic medication seems warranted. These long-term results indicate that PTRA is the treatment of choice in patients with renovascular hypertension.  相似文献   
63.
Aronchick  JM; Epstein  DM; Gefter  WB; Miller  WT 《Radiology》1988,168(3):675-678
Five patients with chronic traumatic diaphragmatic hernia presented with symptoms of acute intestinal obstruction and unilateral pleural effusion. In each case, infarcted herniated abdominal structures were found at surgery. The presence of an ipsilateral pleural effusion is an important radiographic sign, which may indicate strangulation in patients with chronic traumatic diaphragmatic hernia.  相似文献   
64.
A method to decrease the intensity of fat by reversal of the section-select gradient is demonstrated. This technique takes advantage of the chemical shift in section location.  相似文献   
65.
参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨   总被引:10,自引:0,他引:10  
徐皓亮  刘宛斌 《药学学报》1997,32(7):502-506
用大鼠动静脉血栓形成模型,研究参三七皂甙Rg1抗血栓作用。结果表明,参三七皂甙Rg1可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(tPA)活性和活性型tPA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg1可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg1抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关  相似文献   
66.
To further evaluate the effects of flurazepam on EEG during sleep, following 7 nights of placebo baseline, flurazepam (30 mg) was administered to 6 young adult poor sleepers for 10 additional nights while 6 other young adult poor sleepers continued to receive placebo capsules in a double-blind paradigm. Three placebo follow-up nights were recorded 2--3 weeks post-treatment. Twelve good sleepers received only placebo capsules for the first 7 nights. Delta waves, 0.5--2 c/sec, and sleep spindles were counted on-line by a phasic detector. Delta activity was also analyzed off-line by PDP-12 computer for only the first 4 h of sleep and involved a comparison over stages of sleep. Click-evoked K-complexes during NREM sleep were analyzed for 6 good sleepers and 11 poor sleepers. Repeated use of flurazepam caused a gradual decrease in delta amplitude and count, and a gradual increase in sleep spindle rate. The decrease in delta amplitude was seen in all sleep stages, but the decrease was significant only during SWS and stage 2. The decrease in delta amplitude was significant by the 3rd drug night, but the rate of amplitude decrease tended to slow with continued treatment. The decrease in delta count was less pronounced and more gradual over drug nights than the rate of decrease in amplitude. Flurazepam also significantly reduced evoked K-complex amplitude but did not affect latency. Sleep spindle rate was significantly increased by drug night 5. Results of this study indicate that the reduction of SWS with flurazepam during the initial drug nights is due primarily to the decrease in delta amplitude, but, with continued use, the decrease in delta count also contributes to the decrease in stage 4 sleep.  相似文献   
67.
68.
Short latency somatosensory evoked potentials in infants   总被引:4,自引:0,他引:4  
Short latency somatosensory evoked potentials (SEPs) to unilateral median nerve electrical stimulation were recorded from normal infants at birth and at 2, 4, 6, 8, 10 and 12 months of age. Three channels were recorded: Erb's point-Fz; C II (over 2nd cervical vertebra)-Fz; contralateral C' (2 cm posterior to C3 or C4)-Fz. Sweep time = 50 msec. At birth, the C II potential was seen in all infants; the Erb's point and C' potentials were seen in two-thirds. All older infants had well developed potentials at all sites. The mean latency of the Erb's point potential was stable over time. The latency of the C II potential decreased with maturation. At C', 4 components were seen, the latencies of which decreased with maturation: N1, P1, N2 and P2. The duration of N1 and P1 decreased with maturation. Standard deviations were relatively small for latencies and large for amplitudes. SEPs were adversely affected by using the 60 c/sec filter. Increasing the low frequency filter from 1 to 30 c/sec changed SEP, particularly in younger infants. Abnormal SEPs were seen in prematures surviving periventricular hemorrhage.  相似文献   
69.
70.
Biomarkers that could possibly discriminate between healthy controls and patients with dementias of the Alzheimer's type (AD) and vascular dementia (VaD) were investigated. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition TR (DSM IV TR) was used to diagnose for dementia in Trinidad. Healthy seniors greater than 60 years old were controls. All participants were administered the Mini-Mental State Examination (MMSE) and had blood analyzed for levels of C-reactive protein (CRP), total homocysteine (tHcy) and microglial antibodies (MgAb). Plasma tHcy was determined on the Abbot AxSym, serum CRP concentrations were measured using the Tina-Quant sCRP (Latex) high sensitive immunoturbidimetric assay and serum MgAb were examined on frozen rat brain sections. The study was carried out on 29 patients that fulfilled the inclusion criteria and 46 controls. Of the patients 65.5% had AD and 34.5% had VaD. Significant differences were found between the mean MMSE scores of the different types of dementias and controls. MgAb presence as well as tHcy were able to distinguish between controls and dementia of the AD and VaD type, respectively. The MMSE is a good discriminative tool for dementias. Serum MgAbs are a possible biomarker for Alzheimer disease pathology and tHcy is elevated in patients with vascular dementia.  相似文献   
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