Physical function maintenance in brain-dead pregnancy refers to a medical technology that， after a pregnant woman being brain-dead， sustains her uterine and related physiological functions through medical intervention， creates conditions for the normal development of the embryo （fetus）， and performs a cesarean section at an appropriate gestational week to achieve live birth. The implementation of the physical function maintenance technologies in brain-dead pregnancy breaks through the existing procreation paradigm， bearing clinical significance in protecting the life potential of the fetus and alleviating the emotional impact on kinship ethics. Meanwhile， it also faces restrictions by ethical and legal dilemmas and urgently necessitates the “responsive” support of bioethics law. The tension between dignity in death and the protection of potential life， the lack of opportunities for autonomous consent， the ambiguity of surrogate consent rules， and conflicts with traditional Chinese bioethical concepts collectively reflect the ethical concerns over the implementation of physical function maintenance technologies in brain-dead pregnancy. However， the bioethical and legal status of fetal potential life， as well as presumed consent and surrogate consent as permissible forms of informed consent under special conditions， validates the legitimate basis of maternal physiologic support after brain death. In terms of countermeasures， it is essential to adhere to the disputable approach of “case-by-case deliberation” in bioethics law. Based on the specific circumstances of individual clinical cases， it is also necessary to balance and consider multiple ethical evaluation factors， including the clear prior will expression of the parties concerned， fetal development and survival possibility， and the decision-making results of surrogate consent.

Background and objective For highly aggressive small cell lung cancer (SCLC), early diagnosis is im-portant for its prognosis, but the current inspection methods are more limited, with poor specificity of the traditional imaging methods, and the high cost of PET/CT, difcult to popularization and application. SCLC is kind of neuroendocrine tumors, high expression of somatostatin receptors, which is the cornerstone of its early molecular imaging diagnosis. Te aim of this study is to observe the biodistribution and metabolism of 99mTc-octreotide in normal and the human SCLC bearing nude mice. Methods Dynamic and static scintigraphy at 0.5 h, 2 h, 3 h, 4 h were performed in both normal and tumor bearing nude mice afer intravenous injection of 99mTc-octreotide. Te technique of drawing region of interest (ROI) was used to obtain the aver-aged pixel counts and the activity-time (A-T) curve of brain, heart, lung, liver, kidney, tumor, respectively. Results ① Te biodistribution study in normal nude mice showed highest uptake in kidney and liver, lower in lung and heart, lowest in brain. Most 99mTc-octreotide was excreted via kidney. ② All tumors were displayed clearly at 3 h postinjection of 99mTc-octreotide. Te averaged T/N ratio at 0.5 h, 2 h, 3 h, 4 h postinjection of 99mTc-octreotide was 1.163±0.03, 2.08±0.12, 3.03±0.23, 2.689±0.31, respectively (F=51.69, P<0.000,1). Te radioactivity of tumor was lower than liver, and similar with the lung. Te curve of tu-mor showed a radioactivity peak at 2 min-3 min postinjection. Conclusion 99mTc-octreotide receptor imaging on nude mice bearing SCLC shares high positive rate, especially at 3 h postinjection.