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11.
Safety of cryopreservation straws for human gametes or embryos: a study with human immunodeficiency virus-1 under cryopreservation conditions 总被引:3,自引:0,他引:3
12.
J. Mertens J. Eersels W. Vanryckeghem 《European journal of nuclear medicine and molecular imaging》1987,13(3):159-160
A new high yield 123I radioiodination (97%), based on the Cu(I) assisted isotopic exchange in an ethanol water mixture, of 15(p-I-phenyl)-9 methyl pentadecanoic acid, a potential myocardial tracer, is proposed. The method allows a true kit preparation of radioiodinated phenyl fatty acids for a substrate concentration of ±10-6 moles. High specific activities (>0.1 mCi/g) can be obtained when coupling the labelling method to HPLC purification with an overall radiochemical yield of 75%. 相似文献
13.
目的 :探讨卵巢交界性上皮性肿瘤的 DNA含量、倍体分析、S期比例等特点 ,及与组织学分级、预后的关系。方法 :通过计算机图像分析仪 (ICM)测定了 2 2例卵巢交界性肿瘤的 DNA含量 ,并以 38例卵巢良恶性囊性上皮性肿瘤为对照 ,进行倍体分析、S期比例、DI测定。结果 :卵巢交界性肿瘤 DI值 1.11± 0 .0 7,S期比例 33.2 1± 13.72 % ,与良恶性组差异均有显著性意义 (P<0 .0 1)。 2 2例交界性肿瘤中 4例为异倍体肿瘤 ,与恶性组差异有显著性意义 (P<0 .0 1)。 3例复发病例与同组比较其 DI值差异有显著意义 (P<0 .0 1) ,异倍体肿瘤多见。结论 :ICM具有方便、可靠的特点 ,通过测定 DI值、S期比例倍体分析可提示卵巢肿瘤的增殖及预后情况 ,评估潜在恶性的卵巢上皮性肿瘤 ,为临床防治提供更多的信息 相似文献
14.
15.
Xin Sun Yunfeng Guo Shengdu Yang Kai Wang Lan Xie Bai Xue 《Macromolecular chemistry and physics.》2023,224(15):2300072
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields. 相似文献
16.
Many people's lives have been extended by the miracles of modern medicine and technology. However, although the use of these new technologies and drugs may keep people alive longer, the question arises about the quality of that extended life. This paper reviews one physician's apparent preoccupation with assisted suicide in order to introduce the controversy regarding the ethical, moral and legal implications of physician-assisted suicide in the USA. We discuss the arguments in favour of and against assisted suicide in the context of quality of life, individual autonomy versus communal responsibility, and professional autonomy. Occupational therapy, in particular, may be ethically challenged since one can argue that its aim is to help people lead a meaningful and purposeful life despite severe performance deficits. Copyright © 1999 Whurr Publishers Ltd. 相似文献
17.
Summary Contusions and lacerations of the frontal lobes are very frequent; 43.4% in the whole series of traumatic brain mass lesions. Clinical, ICP, CT scan data and neuropathological findings in patients with such lesions are analysed and correlated. Moreover, the clinical features and the outcome of frontal masses undergoing surgery are also compared with similar lesions located in the temporal lobes.Frontal lesions cannot be differentiated on purely clinical grounds and the factors governing the outcome in both locations are the same. On the whole, surgical indications nowadays seem to be rather rare; only lesions behaving truly as expanding lesions with obvious intracranial hypertension benefiting from surgery.Brain contusion-laceration syndromes in general can no longer be considered separate entities. Neither should they be included in the miscellaneous group of traumatic intracranial mass lesions, since the pathophysiological significance of purely extracerebral effusions is entirely different.Traumatic contusions and lacerations and/or intracerebral haematomas, whether frontal or located elsewhere, should, instead, be considered in the context of head injuries of a different degree of gravity, as having collateral features which, on occasion, may call for surgical management. 相似文献
18.
Laparoscopic Assisted Surgery for Crohn''''s Disease an Initial Experience and Results 总被引:2,自引:0,他引:2
栾晓军 《华中科技大学学报(医学英德文版)》2000,20(4)
SurgicaltreatmentisoftenrequiredforpatientswithCrohn'sdiseasewhohaveintestinalstrictureand/orfistula[4.1o.13].Rapidevolutionoflaparoscopicintestinalsurgery,continuousadvancementofinstru-mentation,performanceofmoreextensiveandcom-p1exprocedureshaveledtotheapplicationoflaparo-scopictechniquesinthetreatmentofCrohn'sdis-ease[3'9'12J.Recentreportshavedemonstratedthat,comparedwithtraditional"open"resection,laparo-scopicintestinalsurgeryresultsindecreasedpostoper-ativepain,earlierreturnofintestinalf… 相似文献
19.
Shee-Uan Chen Hong-Nerng Ho Hsin-Fu Chen Kuang-Han Chao Su-Cheng Huang Tzu-Yao Lee Yu-Shih Yang 《Journal of assisted reproduction and genetics》1997,14(3):157-161
Purpose: Using different micropipettes for zona drilling and blastomere aspiration for embryo biopsy is prevalent at centers of preimplantation
genetic diagnosis. The purpose of our study was to simplify the technique by using only one micropipette.
Methods: In this animal model, ICR mouse embryos at the four-cell stage (n=446) were randomly allocated into two groups: a biopsied
group (n=224) for blastomere aspiration and a control group (n=222) without micromanipulation. We used a drilling/biopsy micropipette
to drill a hole in the zona by expulsion of acidified Tyrode’s solution and to aspirate the blastomere by gentle suction with
the same micropipette and pull it out of the zona. One blastomere was biopsied from each embryo.
Results: In all, 222 (99.1%) intact blastomeres were successfully biopsied from 224 embryos. Only two blastomeres were damaged during
aspiration. The capacity for blastocyst development (92.4 vs 93.7%) was not different between the two groups, but the percentages
of embryos hatching (51.8 vs 18.0%) and hatched (29.9 vs 8.1%) were significantly higher in the biopsied group than in the
control group.
Conclusions: This simplified technique of embryo biopsy is safe and highly efficient for obtaining blastomeres for preimplantation genetic
diagnosis and may also facilitate hatching of the blastocysts. 相似文献
20.
Cerebral vascular density is correlated with metabolic demands, which increase in highly active brain areas. External inputs are an essential requirement in the modeling of the visual cortex. Experience-mediated development is very active during the first postnatal month, when congruous blood supply is needed. We studied the development of visual cortex vascularization in relation to experience, comparing rats raised in darkness with rats reared in normal conditions. Vascular density, vascular area and their ratio vs. neuronal density were calculated. Conventionally stained semi-thin sections were used to measure the vascular area by computer assisted morphometry. Animals from both groups were sampled at 14, 21, and 60 days postnatal (dpn). We found a significantly lower density of vessels and neurons as well as a smaller vascular area in dark-reared adult rats while no differences were founded at the other ages. Our results also show no differences between the ratio of vessels/neuron, and vascular area/neuron, between both groups. The absence of visual experience causes decrease of cortical activity which correlates with lower vessels density and vascular area, without their ratio/neuron being affected. 相似文献