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101.
102.
This study investigated the development of family relationships in lesbian families who conceived after donor insemination (DI). The main characteristics of this unknown family structure were analysed. An anonymous donor was used to conceive, the family unit consisted of two mothers and a father was non-existent, and both women had a homosexual orientation. A total of 50 lesbian couples who conceived after DI with children aged between 1 and 2 years participated in this study, using a standardized interview created for this study. After the birth of their child, 56% of the lesbian mothers (n = 100) would have wanted the identity of the donor to be registered, while 10% would have done so at the time of the insemination. Opinions differed in 12 of the 50 couples: the biological mother was in favour of identity registration while the social mother was not. Both women considered themselves a parent of the child with equally shared responsibilities. Mothers were open about the special features of their family structure with children and within their immediate social network. Only 30% disclosed their lesbian identity in a broader social environment. The features of these newly created families may influence the psychological development of the children and therefore make long-term follow-up studies indispensable.  相似文献   
103.
We demonstrate and compare two phase-insensitive all-optical transistors (AOT's) based on frequency-degenerate quadratic three-wave interactions. In particular, we demonstrate gain using KTP in a type II geometry. Both AOT's exploit the phase insensitivity inherent to three-wave parametric processes when only two fields are input, providing amplification of a small signal at the operating frequency via the interaction with a second-harmonic wave. The first scheme is based on successive up- and down-conversion (i.e., cascading) while the second relies on parametric down-conversion. We obtain gains of 5 and 160 in the two configurations, respectively, with a significant background and output coherent to the pump in the first case, no background and coherence between output and signal in the second  相似文献   
104.
BACKGROUND: Serum creatinine has been reported in previous studies to be a prognostic indicator for overall mortality, in particular in a hypertensive population. METHODS: The Program on the Surgical Control of the Hyperlipidemias (POSCH) was a randomized, controlled clinical trial. All patients had survived a single myocardial infarction, were normotensive, were not obese, were not having heart failure, and were free of diabetes mellitus and renal disease at entry into the study. POSCH had followed its control group patients (N = 417) for a minimum of 7.0 years. In this group, a prospective post hoc analysis of the relationship of baseline serum creatinine with subsequent overall and atherosclerotic coronary heart disease mortality was performed. RESULTS: The baseline serum creatinine values in the control group patients ranged from 0.7 to 1.9 mg/dL (60 to 170 mumol/L), and were found to be independent predictors (P < .01) of both overall mortality and atherosclerotic coronary heart disease mortality. Each 0.1 mg/dL (9 mumol/L) increment in the baseline serum creatinine increased the relative risk for subsequent overall mortality by 36% and the relative risk for subsequent atherosclerotic coronary heart disease mortality by 47%. CONCLUSIONS: These results demonstrate that a serum creatinine value, obtained in normotensive, nonobese, normoglycemic survivors of a myocardial infarction without preexistent renal disease or heart failure, provides independent prognostic information regarding subsequent overall and atherosclerotic coronary heart disease mortality.  相似文献   
105.
106.
Pham  V.D. Vu  T.B. 《Electronics letters》1998,34(5):427-428
The authors present an adaptive space-time reduced-length minimum mean-squared error (MMSE) receiver to suppress co-channel interference in the near-far environment for an asynchronous direct-sequence code-division multiple-access (DS/CDMA) system. Simulation results show that better bit-error rate and faster and more stable convergence are achieved over the existing full- and reduced-length MMSE receivers  相似文献   
107.
The purpose of the study was to identify psychiatric symptoms, neurological impairments, and situational factors associated with the emergence of violence and with its persistence. Psychiatric symptoms were assessed in newly admitted physically assaultive psychiatric patients and nonviolent controls. Patients were than evaluated for 4 weeks to determine the persistence or resolution of these physical assaults. Patients who showed marked resolution of assaults were classified as transiently violent (n = 41), and those who remained assaultive throughout were categorized as persistently violent (n = 34). At the end of 4 weeks, all patients received a comprehensive psychiatric and neurological assessment. Physical assaults were associated initially with prominent positive psychotic symptoms. Both transiently and persistently violent patients were more psychotic than the nonviolent controls; however transiently violent patients showed better resolution of these symptoms over the 4 weeks. They also evidenced less frontal lobe impairment on the neurological examination than the persistently violent patients. The two violent groups differed in their susceptibility to environmental influences: the surrounding ward agitation fostered physical assaults in transiently but not in persistently violent patients. This differentiation between transiently and persistently violent patients has major implications for the comprehensive treatment of violent behavior.  相似文献   
108.
109.
Structure-activity studies of human tumour necrosis factors   总被引:3,自引:0,他引:3  
The mechanism by which tumour necrosis factors (TNF and lymphotoxin,also called TNFß and TNFß respectively) exerttheir cytotoxic activity on many malignant cells, remains largelyunknown. Furthermore, the broad array of differentiation (geneinduction) and mitogenic activities towards many primary cellsis still a subject of intensive investigation. TNF is an importantmediator in inflammation, immune responses and infection-relatedphenomena and these activities contribute to the severe toxidtyseen when TNF is used as an anticancer agent. The first stepin the mechanism of action is the specific binding of the ligandto its receptors and dissection of the molecular mechanism involvedin this interaction is the subject of this review. The reasonsfor the interest in this aspect are obvious: first, the developmentof strong antagonistic TNF analogues can be useful in dampeningthe potentially lethal or debilitating effects of an overproductionof the cytokine (as in septic shock or rheumatoid arthritis).Secondly, since two distinct TNF receptors exist, constructionof TNF muteins that distinguish between both types may leadto derivatives of this plekrtropic agent with a more restrictedbiological activity pattern. Ideally, one would like to developa TNF mutant that has retained its cytotoxic action on tumourcells without inducing the deleterious systemic toxteity. Suchan optimized TNF molecule could become a potent anticancer agent  相似文献   
110.
This paper presents the design and fabrication of three miniaturized mechanical sensors to demonstrate the three-dimensional machining capabilities of micro-electro-discharge machining (EDM). The first sensor is an inertial bi-axial inclination sensor. The displacement of an inertial mass is measured optically by means of a two-dimensional position sensitive device (PSD). The machining freedom of micro-EDM makes it possible to produce both sensor and housing in one monolithic structure. The second sensor is an inertial uni-axial inclination sensor, which demonstrates the compatibility of the micro-EDM technology with the conventional photolithographic micromachining technologies. The mechanical structure of the sensor is machined by micro-EDM and the capacitive sensing part is produced by lithography. The aim of the integration is to set up a hybrid technology, which inherits the benefits of both micro-EDM and photolithography. The third miniaturized sensor is a three-component force sensor. The mechanical structure of the force sensor converts forces into displacements, which are measured optically. The mechanical structure of the force sensor is produced by wire-EDM and micro-EDM.  相似文献   
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