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1.
Traumatic infarction of the spinal cord in children 总被引:2,自引:0,他引:2
J U Choi H J Hoffman E B Hendrick R P Humphreys W S Keith 《Journal of neurosurgery》1986,65(5):608-610
Infarction of the spinal cord in childhood is rarely due to trauma. During a 15-year period (1971 to 1985), eight children were admitted to The Hospital for Sick Children, Toronto, with a diagnosis of traumatic infarction of the spinal cord. All of these patients had delayed onset of neurological signs varying between 2 hours and 4 days after their initial trauma. No bone abnormalities were seen on plain spine x-ray films. Myelography was carried out in seven of these children and found to be normal in all seven. Six patients who were paraplegic at the time of admission remained permanently paraplegic, but two with incomplete cord signs did show some improvement. 相似文献
2.
Similar dose responsiveness of hepatic glycogenolysis and gluconeogenesis to glucagon in vivo 总被引:6,自引:0,他引:6
R W Stevenson K E Steiner M A Davis G K Hendrick P E Williams W W Lacy L Brown P Donahue D B Lacy A D Cherrington 《Diabetes》1987,36(3):382-389
This study was undertaken to determine whether the dose-dependent effect of glucagon on gluconeogenesis parallels its effect on hepatic glycogenolysis in conscious overnight-fasted dogs. Endogenous insulin and glucagon secretion were inhibited by somatostatin (0.8 micrograms X kg-1 X min-1), and intraportal replacement infusions of insulin (213 +/- 28 microU X kg-1 X min-1) and glucagon (0.65 ng X kg-1 X min-1) were given to maintain basal hormone concentrations for 2 h (12 +/- 2 microU/ml and 108 +/- 23 pg/ml, respectively). The glucagon infusion was then increased 2-, 4-, 8-, or 12-fold for 3 h, whereas the rate of insulin infusion was left unchanged. Glucose production (GP) was determined with 3-[3H]glucose, and gluconeogenesis (GNG) was assessed with tracer (U-[14C]alanine conversion to [14C]glucose) and arteriovenous difference (hepatic fractional extraction of alanine, FEA) techniques. Increases in plasma glucagon of 53 +/- 8, 199 +/- 48, 402 +/- 28, and 697 +/- 149 pg/ml resulted in initial (15-30 min) increases in GP of 1.1 +/- 0.4 (N = 4), 4.9 +/- 0.5 (N = 4), 6.5 +/- 0.6 (N = 6), and 7.7 +/- 1.4 (N = 4) mg X kg-1 X min-1, respectively; increases in GNG (approximately 3 h) of 48 +/- 19, 151 +/- 50, 161 +/- 25, and 157 +/- 7%, respectively; and increases in FEA (3 h) of 0.14 +/- 0.07, 0.37 +/- 0.05, 0.42 +/- 0.04, and 0.40 +/- 0.17, respectively. In conclusion, GNG and glycogenolysis were similarly sensitive to stimulation by glucagon in vivo, and the dose-response curves were markedly parallel. 相似文献
3.
Interaction between insulin and glucose-delivery route in regulation of net hepatic glucose uptake in conscious dogs 总被引:5,自引:0,他引:5
B A Adkins-Marshall S R Myers G K Hendrick P E Williams K Triebwasser B Floyd A D Cherrington 《Diabetes》1990,39(1):87-95
In the presence of fixed basal levels of insulin, the route of intravenous glucose delivery (protal vs. peripheral) determines whether net hepatic glucose uptake (NHGU) occurs. Our aims were to determine if the route of intravenous glucose delivery also plays a role in regulating NHGU in the presence of hyperinsulinemia and to determine if length of fast (18 vs. 36 h) influences regulation of NHGU. Five conscious dogs fasted 18 h were given somatostatin and replacement insulin (245 +/- 34 microU.kg-1.min-1) and glucagon (0.65 ng.kg-1.min-1) infusions intraportally. After a 40-min control period, the insulin infusion rate was increased fourfold, and glucose was infused for 3 h. Glucose was given either through a peripheral vein or the portal vein for 90 min to double the glucose load reaching the liver. The order of infusions was randomized. NHGU was measured with the arterial - venous difference technique. Insulin and glucagon levels were 12 +/- 2, 35 +/- 6, and 36 +/- 5 microU/ml and 55 +/- 12, 61 +/- 13, and 59 +/- 7 pg/ml during the control, peripheral, and portal infusions, respectively. The glucose infusion rate, the load of glucose reaching the liver, and the arterial-portal plasma glucose gradient were 0, 9.58 +/- 2.28, and 10.44 +/- 2.94 mg.kg-1.min-1; 29.4 +/- 3.6, 56.8 +/- 3.4, and 56.8 +/- 2.8 mg.kg-1.min-1; and 2 +/- 1, 5 +/- 1, and -51 +/- 15 mg/dl during the same periods.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Dr. George Soh 《Australian and New Zealand journal of public health》1992,16(1):103-106
Abstract: This study examined physical and financial arrangements for medical care of institutionalised elderly people in Singapore. Chief administrators of all long-term care facilities were interviewed on the existing arrangements for medical care of their residents. Results showed that 66 out of a total of 68 (97%) homes arranged medical care for residents. Of those, 29 homes offered on-site medical care with alternative arrangements when the in-house facilities were not operating. While government-owned homes would pay for all medical costs incurred by their residents, over 48% of voluntary homes and 87% of commercial homes required residents to be financially responsible for their care. The availability of financial support given to residents for payment of medical care was found to be associated with the type of sponsorship of the homes. While there was adequate physical access to medical care, the lack of financial support would pose a potential barrier to use of medical care for institutionalised elderly people. 相似文献
5.
Hy De Lee Euy Young Soh Hoon Sang Chi Byong Ro Kim Kyong Sik Lee Kyung Soon Song Hyun Joo Jung 《Surgery today》1990,20(2):180-185
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in
relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed
significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02
per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer
patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic
nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis
in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05)
than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without
axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy. 相似文献
6.
G Soh 《Tropical dental journal》1992,15(1):25-29
Prevention has been recognized as a cost-effective method for the control of oral diseases. Knowledge of prevention can influence preventive dental behavior. This study surveyed knowledge on the prevention of dental caries and gum disease among a selected group of adults. Respondents were asked to indicate the importance of numerous preventive measures for prevention of both categories of oral diseases. Results showed that while respondents appropriately identified the importance of regular brushing for prevention, the role of flossing is underestimated. Similarly, there was a lack of appreciation for the value of various fluoride treatment modalities in preventing dental caries. A lack of understanding of dental sealants was also evident. It is concluded that public knowledge on prevention of dental caries and gum disease deviates greatly from current scientific information. 相似文献
7.
A valid and reproducible system for determining basic cardiac life support (BCLS) skills can help to evaluate the effect of instruction courses and to estimate the results of educational activities. The aim of this study was to develop and test such a system in accordance with the Standards and Guidelines of the American Heart Association (AHA). Five criteria were defined in advance towards such a system (1) Inadequate techniques must be reflected by a fail score. (2) Skilled persons should achieve a pass score. (3) The effect of training must be reflected by an improvement of the score. (4) Inter- and intra-observer variability must be negligible. (5) The system should be simple to apply. The system was developed, and in order to test the system, the BCLS skills of 40 ambulance nurses were tested once and those of 148 lay people twice. All cardiopulmonary resuscitation (CPR) attempts were performed on a mannequin. The relevant parameters of the attempt were continuously recorded and printed. Penalty points were assigned in a predefined way for aberrations of the techniques advised in the Standards and Guidelines. The system satisfied the five criteria mentioned above. It therefore offers a reliable and reproducible evaluation of BCLS skills. 相似文献
8.
Characterization of htAKR, a novel gene product in the aldo-keto reductase family specifically expressed in human testis 总被引:1,自引:0,他引:1
Azuma Y Nishinaka T Ushijima S Soh J Katsuyama M Lu HP Kawata M Yabe-Nishimura C Miki T 《Molecular human reproduction》2004,10(7):527-533
In human testis, expression of a novel member of the aldo-keto reductase family was identified. Based on its testis-specific expression, we termed this protein human testis aldo-keto reductase (htAKR). In addition to four major isoforms, the existence of multiple alternatively spliced products of htAKR was detected using RT-PCR followed by nested PCR. htAKR was a homologue of mouse liver keto-reductase, AKR1E1, with close similarity in their genomic organizations. htAKR4, the longest isoform, was expressed as a non-fused native form. It exhibited a limited activity toward 9,10-phenanthrenequinone, while no activity toward the steroids or prostaglandins was demonstrated. Using the laser capture microdissection technique and RT-PCR, expression of htAKR was detected in testicular germ cells as well as in interstitial cells. The levels of htAKR mRNA in the tissues obtained from seminoma were much lower than those in normal testes. A significant decline in the htAKR expression was observed when NEC8, a cell line originated from a human testicular germ cell tumour, was exposed to phorbol 12-myristate 13-acetate or 5alpha-dihydrotestosterone. These results indicate that the expression of htAKR, down-regulated in the testicular tumour, is possibly controlled by mitogenic and hormonal signals. 相似文献
9.
Expression of interleukin-18 by nasopharyngeal carcinoma cells: a factor that possibly initiates the massive leukocyte infiltration 总被引:4,自引:0,他引:4
Interleukin-18 (IL-18) is a single-chain cytokine that is produced by various cells. With interleukin-12 (IL-12), it synergistically stimulates activated T cells and natural killer (NK) cells to produce interferon-gamma (IFN-gamma). Nasopharyngeal carcinoma (NPC) is the most common form of nasal and nasopharyngeal malignancy, and in NPC tumor tissues there is an intense leukocyte infiltration comprising predominantly T cells and macrophages. We previously showed an increased expression of IFN-gamma in the infiltrating T cells. To identify the cells that provide IL-12 and IL-18 for stimulating the expression of IFN-gamma in activated T cells, NPC cell lines CNE-2 and HK-1, as well as biopsies obtained from NPC and control individuals, were examined. CNE-2 and HK-1 cells were found to express messenger RNA encoding IL-18, but not IL-12. Secreted IL-18 was detected in the culture supernatant. Addition of a caspase-1 inhibitor decreased the secretion level, indicating that this IL-18 secretion was caspase-1 dependent. Moreover, the in vitro IL-18 production in NPC cell lines correlated with the NPC tumor cells in situ. NPC tumor cells in the biopsies produced IL-18, as detected by immunohistochemistry and immunofluorescent double staining. In contrast, IL-18 expression was not observed in the control biopsies. We suggest that IL-18 secreted by NPC tumor cells plays a role in initiating the leukocyte infiltration process. IL-18 stimulates T cells and NK cells to produce IFN-gamma, which consequently activates macrophages and other immune cells to secrete chemokines to start a leukocyte recruitment cascade. 相似文献
10.
Shin HS Johng HM Lee BC Cho SI Soh KS Baik KY Yoo JS Soh KS 《Anatomical record. Part B, New anatomist》2005,284(1):35-40
Threadlike structures on the surfaces of internal organs, which are thought to be part of the Bonghan duct system, were first reported about 40 years ago, but have been largely ignored since then. Recently, they were rediscovered, and in this study we discuss the Feulgen reaction that specifically stains DNA in order to identify these structures on the surface of rabbit livers as part of the Bonghan system. The distribution, shapes, and sizes of their nuclei are found to be similar to those of intravascular threadlike structures. The endothelial nuclei are rod-shaped, 10-20 mum long, and aligned in a broken-line striped fashion. The threadlike structure consists of a bundle of several subducts, which is a characteristic feature of Bonghan ducts and distinguishes them morphologically from lymphatic vessels. In addition, the Feulgen reaction clearly demonstrates that the subducts pass through a corpuscle, which is usually irregular or oval-shaped and is connected to two or several threadlike structures that form a web on the surfaces of organs. Furthermore, spherical granules of about 1 mum in diameter are detected in the subducts. These granules were well stained by using the Feulgen reaction, which implies that they contain DNA. According to previous reports, a granule is a type of microcell and plays an essential role in the physiology and therapeutic effect of the Bonghan system and acupuncture. This role has yet to be elucidated. 相似文献