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1.
2.
The latest remarkable technological advances in assisted reproduction, which enable cryopreservation of spermatozoa, embryos and ovarian tissue, raise difficult and debatable legal, social, ethical and moral issues concerning the right to posthumous reproduction. Furthermore, reports on the attitudes of the general public and of centres licensed for infertility treatment in the United Kingdom found that the majority of women and centres support the idea of posthumous reproduction. In this paper we review the data published on this issue, and after considering the various aspects, we conclude that each case should be discussed and authorized by a multidisciplinary committee that includes physicians, clergy, psychiatrists, psychologists, sociologists and other appropriate parties. In our opinion, the main principles that should guide this committee would allow posthumous reproduction in the context of marriage when a prior consent exists. For unmarried persons, post-mortem donation of gametes should be done only anonymously, if they are in agreement with existing laws concerning infertility treatments in every country and after appropriate consent and proper counselling. Moreover, any case which involves consanguinity or a possibility of incest should be forbidden, both for ethical and genetic reasons. In a case of pre-existing siblings, they should be consulted and their informed consent should be granted in advance so as to avoid legal problems in the inheritance of property.   相似文献   
3.
Preimplantation genetic diagnosis principles and ethics   总被引:4,自引:0,他引:4  
  相似文献   
4.
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein.  相似文献   
5.
6.
Owing to the disparity between the supply of kidney donors and demand, the use of organs from older deceased donors was initiated in recent years. The potentially poor outcome of these grafts is a major concern. This retrospective study compares graft and patient 1-year survivals between recipients from expanded-criteria donors (ECD; n = 30) and standard-criteria donors (SCD; n = 104). Rates of delayed graft function (DGF), acute rejection (AR), and chronic injury in the pre-implantation biopsy were also assessed. Increasing donor age was associated with increased rates of DGF, and DGF correlated with AR. Cold ischemia time >30 hours was associated with worse graft outcomes. Induction with Simulect correlated with better patient survival compared with Timoglobulina. Chronic injury pre-implantation biopsy correlated with worse renal function, but graft survival was similar. Death-censored graft survival at 1 year was 90% and patient survival 82%, and these were similar in ECD and SCD recipients. Selection of transplant candidates for ECD kidneys must be performed with caution. One-year graft survival was similar to that of SCD kidneys, but kidney function was worse during the same period. This may result in poorer graft survival over longer follow-up.  相似文献   
7.

Purpose

A diet with polyunsaturated fatty acid (PUFA) supplementation has been reported to reduce renal and cardiac diseases. This study sought to elucidate whether PUFAs derived from plant or marine oils could have beneficial effects on the progression of experimental chronic renal failure (CRF).

Methods

Experimental CRF was achieved by a 5/6 nephrectomy model. Male Wistar rats were divided into groups and given daily supplements of fish oil (group FO), flaxseed oil (group FXO), or soybean oil (control?Cgroup SO) for 30?days. Serum creatinine (sCr), 24-h proteinuria, total cholesterol, triglycerides, and creatinine clearance (CLcr) were measured at day 0 and 30?days after surgery when the rats were euthanized for histological analysis of the remnant kidney.

Results

After 30?days, we observed lower levels of sCr in the groups supplemented with PUFA when compared with the control group (FO: 0.92?±?0.13; FXO: 1.06?±?0.28; SO: 1.32?±?0.47?mg/dL) and significantly slower variations of sCr (??sCr) in the groups treated with PUFAs (FO?=?0.35?±?0.16; FXO?=?0.47?±?0.31; OS?=?0.72?±?0.43; mg/dL, P?=?0.041). Similarly, the CLcr of both of the groups that received PUFAs was significantly slower than the rats in the control group (FO: 0.45?±?0.15; FXO: 0.60?±?0.09; SO: 0.28?±?0.06?mL/min/day; P?=?0.01). The rats that received PUFA supplements also presented significantly less histological lesions compared with the control group.

Conclusions

These results suggest a beneficial effect of dietary supplementation with flaxseed or fish oil in rats with CRF.  相似文献   
8.
Objective To explore the characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Seven patients with arrhythmogenic right ventricular cardiomyopathy and 34 members of three families were studied. All patients and family members underwent history collection, clinical examination, electrocardiogram (ECG), two-dimensional echocardiography (2-DE) and a signal averaging electrocardiogram. Programmed ventricular stimulation was performed in five patients. Results All patients and family members had normal morphologic characteristics and normal function of the left ventricular by 2-DE. Fourteen persons had abnormal findings indicating ARVC. Five had enlargement of the right ventricular with diffused hypocontractility, eight had thin and systolic bulging in the focal anterior wall with hypokinesia and one had bulging of the inferior wall. Twenty-five persons (seven patients and 18 family members) had abnormal findings in ECG. Positive ventricular late potential was recorded in 13 persons (six patients). Two to three monomorphic ventricular tachycardia (VT) with left bundle branch block (LBBB) configurations were induced in five patients. Ventricular fibrillation was induced in two patients during the electrophysiologic study (EPS). Five patients had very high pacing threshold and/or ineffective pacing in one or many regions of the right ventricle. Two members of one family died suddenly. One member was a dwarf with ARVC. Spontaneous VT with a left bundle branch block (LBBB) configuration was recorded in five patients, polymorphic VT with extremely short coupling interval in one, and premature ventricular complexes with LBBB configuration in 12 (six patients). Conclusion Our familial study strongly suggests that ARVC may be a hereditary disease and it is helpful in the diagnosis and detection of ARVC. The most common manifestations were abnormal structure and function of the right ventricle and abnormal ECG of repolarization and ventricular arrhythmia which originates from the right ventricle.  相似文献   
9.
Castle  V; Coates  G; Kelton  JG; Andrew  M 《Blood》1987,70(3):652-656
Thrombocytopenia is a common occurrence (20%) in sick neonates, but the causes have not been well studied. In this report we demonstrate that thrombocytopenia in the neonate is characterized by increased platelet destruction as shown by shortened homologous 111In-oxine-labeled platelet life spans. Thirty-one prospectively studied thrombocytopenic neonates were investigated by measuring the 111In-labeled platelet life span, platelet-associated IgG (PAIgG), and coagulation screening tests. In every infant, the thrombocytopenia was shown to have a destructive component since the mean platelet life span was significantly shortened to 65 +/- 6 (mean +/- SEM) hours with a range of one to 128 hours compared with adult values (212 +/- 8; range, 140 to 260; gamma function analysis). The platelet survival was directly related to the lowest platelet count and inversely related to both the highest mean platelet volume and duration of the thrombocytopenia. In 22 infants the percent recovery of the radiolabeled platelets was less than 50%, which suggested that increased sequestration also contributed to the thrombocytopenia. Infants with laboratory evidence of disseminated intravascular coagulation (n = 8) or immune platelet destruction evidenced by elevated levels of PAIgG (n = 13) had even shorter platelet survivals and a more severe thrombocytopenia compared with the ten infants in whom an underlying cause for the thrombocytopenia was not apparent. Full-body scintigraphic images obtained in 11 infants showed an increased uptake in the spleen and liver, with a spleen-to- liver ratio of 3:1. This study indicates that thrombocytopenia in sick neonates is primarily destructive, with a subgroup having evidence of increased platelet sequestration.  相似文献   
10.
Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.  相似文献   
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