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排序方式: 共有2327条查询结果,搜索用时 15 毫秒
991.
GW van Dijk NC Notermans H Franssen PL Oey JH Wokke 《Canadian Metallurgical Quarterly》1996,243(4):318-322
In an open prospective study we analysed the effect of treatment with intravenous immunoglobulin (IvIg) in three patients with clinically pure sensory neuropathy, two of whom met the clinical, electrophysiological, pathological and cerebrospinal fluid research criteria of the American Academy of Neurology for chronic inflammatory demyelinating polyneuropathy. In all patients, subclinical signs of demyelination were present in motor nerves. Treatment with IvIg resulted in improvement of neurological functions in all three patients and in improvement of the disability score in two of them. 相似文献
992.
993.
I. J. Ford 《Nuclear Engineering and Design》1995,156(3)
A model of axial crack propagation in a pressurized tube is developed which predicts the crack velocity and deformation geometry and the minimum driving pressure. Emphasis is placed upon the stability of propagation. The model also offers a criterion for the appearance of multiple cracks and subsequent fragmentation of the tube wall due to excessive axial bending strains. The model is applied to the rupture of gas pipelines, PWR coolant pipes and fast reactor fuel pins. 相似文献
994.
GW van Dijk NC Notermans Y van der Graaf RC Donders M Hol JH Wokke 《Canadian Metallurgical Quarterly》1997,141(48):2342-2346
OBJECTIVE: To investigate the influence of the age of the patient and the nature of a polyneuropathy on the referral behaviour of general practitioners (GPs). DESIGN: Written questionnaire sent to GPs regarding paper case records of polyneuropathy. SETTING: University Hospital Utrecht, the Netherlands. METHODS: 1590 GPs were asked about their differential diagnosis regarding a paper case record of a patient with polyneuropathy. There were six case records, differing in age (53, 64 and 73 years) and nature of the disease (sensory or sensorimotor polyneuropathy). The GPs were divided into six groups with similar demographic characteristics and type of practice. To avoid focus on polyneuropathy, all GPs also received questions about three other neurological cases (amaurosis fugax, radicular syndrome and vasovagal collapse). RESULTS: The mean response of the questionnaire was 54% (n = 844). Most GPs diagnosed the polyneuropathy (analysis of variance; p < 0.0001). The age of the patient did not influence the diagnosis nor the referral behaviour. At least 73% of the patients with a sensory and 81% of the patients with a sensorimotor polyneuropathy were referred to neurologists for further investigations (chi(2)-test; p < 0.05). CONCLUSION: At least 73% of the GPs referred a patient with polyneuropathy to a neurologist; patients with muscle weakness were referred more often than patients with only sensory disturbances. Referral was not influenced by the age of the patient. 相似文献
995.
996.
H Korr V Philippi C Helg J Schiefer MB Graeber GW Kreutzberg 《Canadian Metallurgical Quarterly》1997,94(6):557-566
Unscheduled DNA synthesis (UDS) of nuclear DNA and mitochondrial (mt) DNA synthetic rates were determined autoradiographically in different cell types of the rodent brain 14 days after unilateral facial nerve transection. In addition to an increased synthetic rate of mtDNA in facial motoneurons 12 h after axotomy, a significant increase of UDS, i.e., DNA repair, and mtDNA synthesis were found in the regenerating facial nucleus 4 days after axotomy. Specificity of the observed labeling was confirmed by injection of 3H2O instead of [3H]thymidine. Using electron microscopic autoradiography, it was further shown that cytoplasmic labeling of neurons was mainly due to incorporation of radioactive label into mitochondria, indicating their subsequent multiplication by division. The observation that Northern blot signals for O6-alkylguanine-DNA-alkyltransferase mRNA from homogenized facial nuclei of both the axotomized and normal side remained unchanged over 14 days after axotomy indicated that the observed DNA-repair activity was not caused by endogenously produced alkylating agents. The combined presence of transiently increased UDS, enhanced mtDNA synthesis and elevated protein synthetic rates of regenerating motoneurons (as shown in the literature) suggests that free radicals produced by mitochondria in injured nerve cells could cause unspecific DNA damage followed by immediate repair. 相似文献
997.
998.
999.
KH Edmiston Y Shoji T Mizoi R Ford A Nachman JM Jessup 《Canadian Metallurgical Quarterly》1998,58(7):1524-1531
Human colorectal carcinoma (CRC) cell survival for the first 24 h after implantation in the hepatic sinusoid determines its potential to colonize the liver. Nearly 10-fold more highly metastatic CX-1 cells survive within the livers of nude mice 24 h after intrasplenic injection than weakly metastatic clone A cells. Because CRCs contact sinusoidal endothelial cells (SECs) during implantation, we sought to determine whether SECs were more toxic to clone A than to CX-1 cells. When 2 x 10(4) vital dye-labeled CRC cells were added to murine SEC monolayers, more than 30% of clone A cells lost calcein AM fluorescence compared to fewer than 5% of CX-1 cells after 24 h of coculture with SECs. Kupffer cells did not mediate this effect, because neither enriched Kupffer cells nor SECs treated with a Kupffer cell inhibitor altered the SEC-mediated toxic effect to clone A cells. Pretreatment with a nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine, superoxide dismutase, or dexamethasone, blocked SEC-mediated toxicity to clone A cells, whereas calcium chelation and catalase did not. In addition, clone A cells were more sensitive to a superoxide donor, 3-morpholinosydnonimine N-ethylcarbamide, than were CX-1 cells, and neither cell line was sensitive to sodium nitroprusside, a nitric oxide donor. Thus, unstimulated murine SECs produce reactive oxygen species that are selectively toxic to weakly metastatic clone A cells. This may be a mechanism by which host liver cells eliminate weakly metastatic neoplastic cells. 相似文献
1000.
SL Monfort GW Asher DE Wildt TC Wood MC Schiewe LR Williamson M Bush WF Rall 《Canadian Metallurgical Quarterly》1993,99(2):459-465
This study tested the efficacy of assisted reproduction (synchronization of oestrus and intrauterine artificial insemination (AI)) in contributing to the captive propagation of an endangered species, the Eld's deer (Cervus eldi thamin). Semen was collected from males preselected on the basis of under-represented genotype. Motility of spermatozoa after thawing from ejaculates diluted with BF5F extender (8% glycerol), frozen on dry ice in 0.5 ml straws and stored in liquid nitrogen was 60-70%. Intravaginal progesterone-releasing devices (controlled internal drug release, CIDR-type G) were inserted into 20 adult Eld's deer hinds for 14 days. In all hinds, semen (7.5-10 x 10(6) motile spermatozoa per uterine horn) was deposited by laparoscopy performed 70 h after removal of the CIDR device. Ovarian activity, before and after AI, was monitored by analysing pregnanediol-3 alpha-glucuronide (PdG) concentrations in voided urine collected three to seven times per week. During the period of CIDR device insertion, urinary PdG profiles were equal to, or above, normal luteal phase concentrations in all hinds. Within 48 h of device withdrawal, PdG concentrations returned to baseline values in 17 of the 20 females, and the onset of behavioural oestrus occurred at this time in 12 hinds. On the basis of sustained increases in urinary PdG, 9 of the 20 hinds were diagnosed as pregnant by 90 days after AI, all of which delivered offspring after a mean gestation of 241.1 days (range, 235-245). Seven singletons (two females, five males) were born alive and survived, and one singleton and one set of twins were stillborn (three females).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献