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11.
12.
An effective regimen for early medical abortion: a report of 2000 consecutive cases 总被引:6,自引:14,他引:6
Ashok P.W.; Penney G.C.; Flett G.M.M.; Templeton A. 《Human reproduction (Oxford, England)》1998,13(10):2962-2965
A combination of the anti-progesterone mifepristone and gemeprostprovides an effective non-surgical method for the inductionof abortion at gestations up to 63 days, achieving completeabortion rates of over 95%. We report our experience with analternate regimen, comprising a reduced dose of mifepristonein combination with vaginal misoprostol. A consecutive seriesof 2000 women requesting early medical abortion at gestationsup to 63 days was studied retrospectively. Each woman receivedmifepristone 200 mg orally, followed 3648 h later bymisoprostol 800 µg vaginally. Of the 2000 women, 39 (2.0%)aborted completely following administration of mifepristonealone and a further 1912 experienced complete abortion followingadministration of misoprostol (a complete abortion rate of 97.5%).Surgical intervention was required in 49 women (2.5%): for incompleteabortion in 27 (1.4%), for missed abortion in seven (0.4%),for continuing pregnancy in 11 (0.6%) and to exclude ectopicpregnancy in four (0.2%). The surgical intervention rate wassignificantly higher among women at gestations 49 days thanamong those at 49 days (3.3 versus 1.5%, P = 0.0193). The regimenappears as effective, in terms of high complete abortion rateand low continuing pregnancy rate, as any published alternative.This regimen has the benefit of being less costly as the doseof mifepristone is 67% lower and misoprostol is substantiallyless expensive than gemeprost. Additionally, misoprostol doesnot require special transport or storage requirements. As such,the combination of mifepristone and gemeprost. 相似文献
13.
Sperm quality in Hodgkin's disease versus non-Hodgkin's lymphoma 总被引:3,自引:4,他引:3
Botchan A; Hauser R; Gamzu R; Yogev L; Lessing JB; Paz G; Yavetz H 《Human reproduction (Oxford, England)》1997,12(1):73-76
The study was conducted to determine the deleterious effect of lymphoma
disease on spermatogenesis and to evaluate the possibility that the disease
is mediated primarily by inherent mechanisms in Hodgkin's disease and
non-Hodgkin's lymphoma patients. A total of 89 patients with lymphoma
disease (Hodgkin's and non-Hodgkin's) were referred for sperm preservation
prior to adjuvant treatments. A comparison was made of pre- and post-thaw
sperm quality between lymphoma patients and healthy volunteers who applied
for sperm donation. This was followed by further assessment of the
differences between patients with Hodgkin's disease and non-Hodgkin's
lymphoma in terms of sperm variables, clinical parameters and blood hormone
concentrations. It was found that patients with lymphoma disease had
significantly impaired pre-freeze and post-thaw sperm quality compared with
that of healthy volunteers. Patients with non-Hodgkin's lymphoma had
spermatozoa of higher quality than patients with Hodgkin's disease. No
differences were found in the clinical or hormonal parameters between these
two groups. As expected, reduced testicular size and abnormal testicular
consistency were correlated with decreased sperm quality. The mere presence
of cancer disease has a direct negative effect on spermatogenesis, which is
probably not related to incidental side-effects. A variable degree of
impairment should be expected with different categories of cancer.
相似文献
14.
M. B. Bromberg G. Pamel B. S. Stephenson A. B. Young J. B. Penney 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,69(1):53-59
Summary High affinity glutamate uptake into corticofugal fiber terminals was measured in the ventrolateral thalamus and red nucleus at varying time intervals after lesions were made by kainic acid in the contralateral interpositus nucleus of the cerebellum in rats. Under similar conditions the density of cortical fiber terminals was estimated using the Fink-Heimer impregnation technique. 1. Glutamate uptake steadily increased in the ventrolateral thalamus up to 60 days after lesions in the contralateral cerebellum. 2. Similar changes were noted in the red nucleus. 3. The changes were dependent on the integrity of corticofugal fibers to the thalamus and red nucleus. 4. No changes in uptake of gammaaminobutyric acid were noted. 5. Saturation curves for glutamate uptake suggested a change in the maximal number of transport sites. 6. Fink-Heimer degeneration studies showed an increase in cortical terminals in the ipsilateral ventrolateral thalamus and in both rostral and caudal regions of the red nucleus following lesions in the contralateral interpositus nucleus. The data are consistent with an increase in the number of cortical fiber terminals in reaction to loss of cerebellar input to the ventrolateral thalamus and red nucleus. This study correlates anatomical and biochemical evidence for collateral sprouting in a model based on electrophysiologic data in the red nucleus and extends the model to include the thalamus. 相似文献
15.
At-risk persons' attitudes toward presymptomatic and prenatal testing of Huntington disease in Michigan 总被引:6,自引:0,他引:6
One hundred fifty-five individuals at 50% risk of inheriting Huntington disease (HD) were given a questionnaire surveying their sociodemographic characteristics, experience with HD, and attitudes toward presymptomatic and prenatal testing in HD. About two-thirds (63.2%) of the persons indicated they would take a presymptomatic test even if no specific treatment was available. Although one-half (49%) of the respondents stated they would make use of a prenatal test, only 43% of these individuals would decide to terminate a heterozygous fetus. Presymptomatic test results indicating carrier status would influence some of the respondents' decisions about marriage and childbearing. This strong interest of at-risk persons to make use of both presymptomatic and prenatal diagnosis in HD indicates the need for well-organized testing programs. These programs must be designed to address the genetic, psychosocial, and ethical issues that may arise in the use of this type of genetic test. 相似文献
16.
F. A. Anderson Jr. B. C. Penney N. A. Patwardhan H. B. Wheeler 《Medical & biological engineering & computing》1980,18(2):234-240
Electrical impedance plethysmography of the lower leg is now a widely used test for detection of deep vein thrombosis. The
origin of the impedance signal is difficult to evaluate in the living subject, and experimental animals have important anatomic
differences. A controlled study on human cadavers was therefore undertaken. Conductive and nonconductive fluids were injected
into the lower legs of cadavers, while electrical impedance changes were recorded utilising a 4-electrode technique. X-ray
studies confirmed the localisation of the injections. Results from ten cadavers showed that significant impedance changes
occurred only in response to injections of saline in the region between the electrodes. Injections of nonconductive silicone
oil caused a small increase in the measured impedance. It is concluded that electrical impedance plethysmography reflects
changes in conductivity confined to the region between the electrodes; and that the ratio of deep to superficial impedance
sensitivity is a function of the electrode spacing. 相似文献
17.
Constrained least-squares restoration of nuclear medicine images: selecting the coarseness function 总被引:1,自引:0,他引:1
B C Penney M A King R B Schwinger S P Baker P Stritzke P W Doherty 《Medical physics》1987,14(5):849-858
Image restoration using the constrained least-squares (CLS) method theoretically adapts to the image being processed. In addition, it only requires knowing the modulation transfer function of the imaging system when applied to nuclear medicine images. Prompted by these observations, a systematic evaluation of the effects of the form of the "coarseness function" [C(f)] used by the CLS method has been conducted. Nine C(f)'s are evaluated using an observer preference and a normalized mean-squared error (NMSE) criterion. This evaluation is conducted for three modulation transfer functions and a wide range of count levels. The results of the subjective studies support using the form of C(f) which has been most widely employed in previous studies, i.e., the form designed to minimize the energy in the second derivative of the restored image. A different form of C(f) is generally found to be optimal by the mean-squared error criterion. The CLS method is then compared to: (1) no processing, (2) count-dependent smoothing, and (3) count-dependent Metz restoration. When evaluated using objective measurements of error and contrast, the CLS method is found to be slightly inferior to the best method, Metz restoration. However, CLS restoration is found to be equal to or better than the other methods when judged by the results of observer preference studies. 相似文献
18.
19.
Eskandar EN Shinobu LA Penney JB Cosgrove GR Counihan TJ 《Journal of neurosurgery》2000,92(3):375-383
OBJECT: Pallidotomy for the treatment of medically refractory Parkinson's disease (PD) has enjoyed renewed popularity. However, the optimal surgical technique, lesion location, and long-term effectiveness of pallidotomy remain subjects of debate. In this article the authors describe their surgical technique for performing pallidotomy without using microelectrode guidance, and the clinical and radiological results of this procedure. METHODS: Patients were evaluated preoperatively by using a battery of validated clinical rating scales and magnetic resonance (MR) imaging of the brain. Individuals with severe treatment-refractory idiopathic PD who were believed to be good candidates for surgery underwent computerized tomography scanning- and MR imaging-guided stereotactic pallidotomy. Intraoperative macrostimulation was used to optimize lesion placement and to avoid injury to nearby structures. Lesion location and size were calculated from MR imaging sequences of the brain obtained within the first 24 hours after surgery and again 3 months later. Clinical examinations were conducted at 1.5, 3, 6, 12, and 24 months after surgery. Seventy-five patients (mean age 61 years, range 38-79 years) underwent unilateral pallidotomy. Significant improvements were observed in the "off' period scores for the activities of daily living portion of the Unified Parkinson's Disease Rating Scale (UPDRS), the UPDRS motor scores, total "on" time, levodopa-induced dyskinesias, and contralateral tremor. These improvements were maintained 24 months postoperatively. The mean lesion volume measured on the immediate postoperative MR image was 73 +/- 5.4 mm3. Radiological analysis suggests that initial lesion volume does not predict outcome. The only permanent major complication was a single visual field defect. CONCLUSIONS: Pallidotomy performed without using microelectrode guidance is a safe and effective treatment for selected patients with medically refractory PD. 相似文献
20.
Epstein–Barr virus–associated smooth‐muscle tumors (EBV‐SMTs) are unique and rare neoplasms described in immunocompromised patients. The case describes a nine‐year‐old female with a history of acute lymphoblastic leukemia with relapse and subsequent allogeneic bone marrow transplantation who presented with multiple EBV‐SMTs of the liver. EBV utilizes the mammalian target of rapamycin (mTOR) pathway for tumor growth, and sirolimus, a mTOR inhibitor, has shown to result in a short‐term response. We now report an extended treatment response with sirolimus in a pediatric patient with an EBV‐SMT. 相似文献