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11.
STUDY OBJECTIVE: To assess the clinical utility of measuring urinary pregnanediol glucuronide in random samples in an infertility practice. DESIGN: Samples of urine were collected from patients approximately 3 weeks from their last menstrual period to ascertain if ovulation had occurred. Each sample was tested for specific gravity before analyzing for pregnanediol glucuronide. Simultaneous venipuncture was performed to compare results from the urinary assay to quantitative measures of serum progesterone (P). SETTING: All patients were randomly sampled. PATIENTS: Three hundred ninety women undergoing pituitary down regulation with leuprolide acetate were chosen for study because they routinely initiate medication after documentation of ovulation. OUTCOME MEASURES: The performance of the urinary pregnanediol glucuronide was evaluated as to its sensitivity, specificity, predictive value, and test efficiency compared with a serum measurement of 2.5 ng/mL and 10.0 ng/mL. RESULTS: The performance characteristics of the pregnanediol glucuronide assay were directly related to the hydration status of the patient at the time of sample collection. Regardless of urine specific gravity, if pregnanediol glucuronide was qualitatively detected (greater than 3 micrograms/mL), serum P was greater than 2.5 ng/mL. However, in cases in which pregnanediol glucuronide was undetected (less than 3 micrograms/mL), results were only accurate when the specific gravity was greater than or equal to 1.020. When comparing urinary pregnanediol glucuronide values to serum greater than 10 ng/mL, both specificity and predictive value of a positive test decreased because of increased numbers of false-positive results. CONCLUSIONS: The enzyme immunoassay measurement for pregnanediol glucuronide may replace the use of serum P in documenting the ovulatory status of many patients. However, all specimens must be checked for specific gravity and if less than 1.020, a serum P should be used to ensure accuracy.  相似文献   
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Excitotoxic neurodegeneration in the rat striatum was induced by direct injection of quinolinic acid. The degree of damage was evaluated in vivo 1 day later by quantitative magnetic resonance imaging (MRI) and 7 days later in the same animals by measuring the activities of the neuronal marker enzymes choline acetyltransferase and glutamic acid decarboxylase. Striatal damage assessed using the two approaches was highly correlated. Moreover the cerebroprotective efficacy of the N-methyl-D-aspartate receptor antagonist CGP 40116 was indistinguishable based on all analytical parameters. MRI, however, was more reproducible than the enzymatic methods and was faster and simpler for routine analyses of excitotoxic damage and cerebroprotection in vivo.  相似文献   
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Ovarian hyperstimulation syndrome (OHSS) is a serious complicationof gonadotrophin usage but it is difficult to accurately predictits occurrence. Previous investigators have identified the combinationof high oestradiol concentrations and oocyte number as beingpredictive in 80% of cases. In this study we sought to identifythe incidence of severe OHSS in patients with high oestradiolconcentrations and large numbers of oocytes and to evaluatethe importance of pregnancy in the development of OHSS. Between1990 and 1993, we studied 139 cycles using two assisted reproductivetechniques [oocyte donor, n =72; in-vitro fertilization (IVF),n = 67] in which either oestradiol (>4000 pg/ml), oocytenumber (>25), or both were elevated. OHSS was diagnosed bystandard criteria. There were no cases of severe OHSS in theoocyte donor group and six in the IVF group. Among 10 patientswith oestradiol concentration >6000 pg/ml and >30 oocytes,only one had OHSS (10%). The relative risk of OHSS with pregnancywas 12 (confidence interval 2.18–66.14). We conclude thatthe risk of OHSS even at high levels of stimulation is lowerthan previously believed. Secondly, donors have a very low riskof OHSS, probably because of the absence of pregnancy. As such,cryopreservation of all oocytes in IVF cycles is a reasonablealternative to cycle cancellation or use of adjunctive medication.  相似文献   
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An altered perception of pain has been described for several psychiatric disorders. To date the influence of adjustment disorders (AD) on pain perception has not been described. Here, we investigated perception of experimentally induced pain in 15 patients suffering from AD (subtype with depressive symptoms) and controls matched for age and sex. Thresholds and tolerances were assessed for thermal and electrical pain on both sides of the body. We found an overall increase of pain thresholds and tolerances in AD patients as compared to controls, predominately on the right side of the body. Analogue findings have been reported for pain perception in major depressive disorder (MDD). Of the data obtained, only thermal pain threshold on the right arm correlated with the severity of depressive symptoms. Although the underlying pathology is elusive it is likely that the mechanisms for reduced pain sensitivity are comparable in MDD and AD.  相似文献   
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Abstract:  Liver transplantation for hepatitis B virus (HBV)-related liver disease has changed from a contraindication to outcomes comparable with non-HBV-related liver transplantations during the last two decades. Mainly the implementation of immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and the use of nucleoside analogs such as lamivudine and adefovir account for this dramatic change. The standard of care in most centers today consists of lamivudine treatment in replicating hepatitis B pre-orthotopic liver transplantation (OLT) and a combination regimen of lamivudine and HBIG post-OLT. With adefovir, a potent antiviral drug became available in recent years that allows for the treatment of patients with lamivudine-resistant tyrosine-methionine-aspartate-aspartate (YMDD)-mutant HBV. In the transplantation setting, first studies indicate that a triple prophylactic therapy consisting of lamivudine, adefovir, and HBIG will become the standard of care for YMDD-mutant-related hepatitis B. With new drugs emerging for the treatment of chronic HBV, there is optimism for new options also in the transplant setting.  相似文献   
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 We employed intracerebral co-transplantation of foetal xenogeneic striatal mouse tissue and allogeneic rat substantia nigra into the adult rat brain to elucidate the effects of xenogeneic mouse graft on the function and survival of an allogeneic rat graft in 6-hydroxydopamine lesioned Sprague-Dawley rats. Foetal mouse striatum (STR) and rat substantia nigra (VM) were transplanted as non-pooled separate deposits or a pooled cell suspension with or without cyclosporin A (Cy A). Immunosuppressed recipients of pooled rat and mouse co-grafts showed a significantly better compensation of amphetamine-induced rotational behaviour compared with non-immunosuppressed animals with pooled rat and mouse co-grafts 3 and 6 weeks post-grafting.Tyrosine hydroxylase (TH) immunohistochemistry revealed a non-significant reduction in survival in pooled (1806.3±367.5 cells) rat and mouse co-transplants without immunosuppression compared with immunosuppressed pooled (3383.3±732.7 cells) animals with allo- and xenogeneic tissue and controls (3506.4±839.3 cells). Graft volumes were significantly reduced in pooled transplants without immunosuppression (0.1±0.026 mm3; ANOVA post-hoc SchefféF-test, P<0.0001) compared with immunosuppressed recipients (0.7±0.1 mm3) and controls (0.6±0.1 mm3). In non-pooled allo- and xenogeneic grafts without immunosuppression the survival rate of the TH-immunoreactive cells and graft volumes were reduced (2359.3±479.5 cells; 0.2±0.043 mm3) compared with immunosuppressed animals (2927.3±946.6 cells; 0.6±0.2 mm3) and controls (2701.1±693.8 cells; 0.3±0.1 mm3) without reaching a level of significance. Rejection of mouse tissue was observed in all non-immunosuppressed recipients. In summary: (i) continued immunosuppression yielded significant beneficial effects on function and beneficial effects on survival of pooled grafts with an immunogenetic disparity; (ii) the rejection of a xenogeneic graft component may compromise survival and function of other, allogeneic graft components; and (iii) transplantation of non-pooled allo- and xenogeneic tissues may result in a better survival of the graft compared with pooled cell suspensions. Received: 25 March 1996 / Accepted: 1 December 1996  相似文献   
20.
Internal fixation of dorsolumbar spinal fractures can be accomplished by dorsal plating or internal fixator. So far, the technique of transpedicular grafting has been applied to fill the vertebral body with cancellous bone. In this paper, we present a new technique of extended transpedicular bone grafting to fill the intervertebral space also. By this means, the disadvantage of secondary loss of height after removal of the metal implants can be prevented.  相似文献   
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