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11.
'Doctors must not kill' 总被引:2,自引:0,他引:2
Four physicians respond to "It's over, Debbie," an anonymous resident physician's account of an incident when he or she injected a terminally ill cancer patient with a lethal dose of morphine (JAMA 1988 Jan 8; 259(2): 272). Gaylin and his colleagues condemn both the physician's violation of legal and ethical norms, and the conduct of JAMA's editor in publishing the article without editorial rebuke or comment. They warn that the issue of active euthanasia "touches medicine at its very moral center," and that, as pressure to legalize euthanasia in response to patient demand increases, the medical profession must repudiate direct and intentional killing of patients and discipline doctors who kill. 相似文献
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Adenosine and active hyperemia in dog skeletal muscle 总被引:5,自引:0,他引:5
14.
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine. 相似文献
15.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
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AIMS: Epstein-Barr virus (EBV) immortalises B cells in vitro and is associated with several malignancies. Most phenotypic effects of EBV are mediated by latent membrane protein 1 (LMP1), which interacts with tumour necrosis factor receptor associated factors (TRAFs) to activate NF-kappaB. This study examines TRAF1 and LMP1 expression in EBV associated lymphoproliferations. METHODS: TRAF1 expression was investigated in 26 Hodgkin lymphomas (HL; 18 EBV+, eight EBV-), seven EBV+ Burkitt lymphomas (BL), two infectious mononucleosis (IM) tonsils, and lymphoreticular tissue from eight chronic virus carriers. Seven anaplastic large cell lymphomas and 10 follicular B cell lymphomas were also studied. Colocalisation of TRAF1 and LMP1 was studied by immunofluorescent double labelling and confocal laser microscopy. RESULTS: TRAF1 colocalises with LMP1 in EBV infected cells in IM. EBV positive lymphocytes from chronic virus carriers were negative for TRAF1 and LMP1. In HL biopsies, TRAF1 was strongly expressed independently of EBV status, whereas all BL cases were TRAF1-. In EBV+ HL cases, TRAF1 colocalised with LMP1. Eight of 10 follicular lymphomas expressed TRAF1 in centroblast-like cells. Four of seven anaplastic large cell lymphomas weakly expressed TRAF1. CONCLUSIONS: These results suggest that in non-neoplastic lymphocytes, TRAF1 expression is dependent on the presence of LMP1, and that in IM B cells in vivo, LMP1 associated signalling pathways are active. In HL, TRAF1 is expressed independently of EBV status, probably because of constitutive NF-kappaB activation. The function of TRAF1 in HL remains to be determined. 相似文献
18.
B. AASTED D. BERNSTEIN D. G. KLAPPER A. EL KHOLY R. M. KRAUSE 《Scandinavian journal of immunology》1979,9(1):61-67
The human lymphokine, leucocyte migration-inhibitory factor (LIF), appears to be a serine esterase and protease by virtue of its susceptibility to the irreversible enzyme inhibitor, phenylmethylsulfonyl fluoride (PMSF), and by the ability of arginine esters and amides to protect LIF against PMSF-induced inactivation. In this paper, three methods are described by which putative substrates for LIF may be investigated. Thus, molecules satisfying the substrate specificities of this lymphokine should (1) protect LIF against inactivation by PMSF, (2) reduce LIF activity in vitro on polymorphonuclear leucocytes, and (3) reduce the esterolytic activity of purified LIF-rich supernatants. The first two reactions were tested by means of the leucocyte migration agarose technique; the third reaction was tested by a sensitive enzyme assay using tritiated tosyl arginine methyl ester as substrate. Guanosine 3',5'-cyclic monophosphoric acid, which is capable of protecting LIF against PMSF-induced inhibition, also inhibited the esterolytic activity of the purified LIF preparation. Four synthetic oligopeptide substrates for trypsin, thombin and plasmin were investigated. Only one, the thrombin- and trypsin-specific benzoyl-phenylalanyl-valyl-agarine-p-nitroanilide, possessed high affinity for the LIF molecule and may therefore prove to be a potent substrate for this lymphokine. 相似文献
19.
Die Anaesthesiologie - 相似文献
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