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181.
S Paterniti MF Falcone P Fiore A Levita A La Camera 《Canadian Metallurgical Quarterly》1998,140(9):953-955
Recently we treated 54 patients with acute epidural haematoma, diagnosed by early CT scan and operated on quickly, within 6 hours after trauma. In 18 cases the volume of the haematoma, calculated by three different methods, was more than 150 cc, and GCS score was equal to or less than 8. In all 18 patients, as well as in another 36, we obtained good results: all patients survived and 17 fully recovered (only one was left with moderate neurological disability). Our experience leads us to the conclusion that even volumes of over 150 cc can be compatible not only with survival but also with very low morbidity, if rapid surgical treatment is performed. 相似文献
182.
MF McCarty 《Canadian Metallurgical Quarterly》1998,68(5):1144-1147
Vascular endothelial growth factor (VEGF) is a cytokine that induces angiogenesis. Angiogenesis is a prominent histologic component of the luteinization process. Luteinization is also characterized by granulosa cell progesterone secretion in response to the luteinizing hormone (LH) surge. Local VEGF production in human pre-ovulatory follicles, induced by LH, was postulated to be a luteinization mediator in women. To investigate this hypothesis, serum and fluid from the dominant follicle of 31 healthy regularly cycling multiparous women undergoing laparoscopic sterilization were obtained. VEGF was measured by enzyme-linked immunosorbent assay, and LH and progesterone were measured by radioimmunoassay. Follicle aspiration was performed at a median of 13 days from the last menstrual period (range 11-17 days). The median pre-ovulatory follicle diameter was 16 mm (range 11-23 mm). Follicle fluid VEGF concentrations (mean 6900 pg/ml, range 1200-17 100 pg/ml) were correlated positively with follicle fluid progesterone concentrations (mean 10 176 nmol/l, range 636-66780 nmol/l, r=0.62, P=0.002). This correlation was even tighter (r=0.87, P < 0.0001) when only samples from the 22 women in the earliest stages of follicle luteinization were considered. In these women serum LH concentrations were also correlated with follicle fluid VEGF concentrations (r=0.51, P=0.02). Our findings demonstrate the close dynamic relationship between VEGF production and early luteinization in human follicles during normal non-stimulated cycles. 相似文献
183.
Several endogenous oscillators determine circadian rhythms. One, light-entrained, is in the suprachiasmatic nuclei (SCN), the others, food-entrained, are in unknown sites. To determine how the hypothalamic ventromedial nuclei (VMN) and feeding affect rhythms, we compared nocturnally active rats fed either ad libitum or for 2 hr/d during light [restricted feeding (RF)] and either with or without colchicine-induced disruption of VMN. We measured rhythms in temperature, locomotor activity, feeding, drinking, corticosterone, and the numbers of cells expressing c-Fos in light/dark in hypothalamic nuclei, the suprachiasmatic nuclei, and two major SCN targets, the subparaventricular zone (sPVNz) and paraventricular thalamus (pvTHAL). c-Fos cells were always light > dark in SCN, whereas the VMN and sPVNz lacked light/dark differences except after RF and RF plus VMN disruption, respectively. Controls fed ad libitum had high-amplitude rhythms and, generally, c-Fos cells dark > light. In RF controls, a c-Fos pattern dark > light occurred in VMN; generally, c-Fos cell numbers increased elsewhere maintaining dark > light. By contrast, levels of corticosterone peaked before food. In rats fed ad libitum, VMN with colchicine markedly reduced rhythm amplitudes, not phase. c-Fos patterns were abolished except in pvTHAL and SCN. In RF, VMN disruption blocked corticosterone and light/dark c-Fos patterns in all nuclei but produced a pattern in the sPVNz like SCN. We conclude that VMN amplify rhythmic output from the SCN, and the RF-induced rhythm in VMN enhances c-Fos activity driven by the SCN. The VMN may contain a food-entrained oscillator, and the sPVNz may integrate output from several oscillators. 相似文献
184.
MF McCarty 《Canadian Metallurgical Quarterly》1994,42(4):215-225
There is considerable evidence that hepatic vagal afferents monitor the availability of liver glycogen and glucose metabolites, and that this mechanism participates in appetite regulation. Thus, promotion of gluconeogenesis and liver glycogen storage may enhance satiety. Hepatic lipid oxidation drives gluconeogenesis by positive allosteric modulation of pyruvate carboxylase and fructodiphosphatase. The rate-limiting enzyme for hepatic lipid oxidation, carnitine acyltransferase I, is activated by exogenous carnitine, and inhibited by malonyl coA. The lipogenesis inhibitor (-)-hydroxycitrate--a natural fruit acid found in the Brindall berry--can decrease production of malonyl coA in hepatocytes by potent inhibition of citrate lyase; many studies demonstrate that (-)-hydroxycitrate can reduce body fat accumulation in growing rats, owing in large part to a reduction in appetite. Joint administration of (-)-hydroxycitrate and carnitine should therefore promote hepatic lipid oxidation, gluconeogenesis, and satiety. Thermogenic effects as well as a reduction of the respiratory quotient can also be predicted. If this technique proves clinically useful in weight management, it could be used in conjunction with chromium picolinate and soluble fiber supplements, which appear to aid hunger control at the level of the hypothalamus and terminal ileum, respectively. 相似文献
185.
STATEMENT OF PROBLEM: The practice of fixed prosthodontic has changed dramatically with the introduction of innovative techniques and materials. Adhesive resin systems are examples of these changes that have led to the popularity of bonded ceramics and resin-retained fixed partial dentures. Today's dentist has the choice of a water-based luting agent (zinc phosphate, zinc polycarboxylate, glass ionomer, or reinforced zinc oxide-eugenol) or a resin system with or without an adhesive. Recent formulations of glass ionomer luting agents include resin components (resin-modified glass ionomers), which are increasingly popular in clinical practice. PURPOSE: This review summarizes the research on these systems with the goal of providing information that will help the reader choose the most suitable material. MATERIAL: The scientific studies have been evaluated in relation to the following categories: (1) biocompatibility, (2) caries or plaque inhibition, (3) microleakage, (4) strength and other mechanical properties, (5) solubility, (6) water sorption, (7) adhesion, (8) setting stresses, (9) wear resistance, (10) color stability, (11) radiopacity, (12) film thickness or viscosity, and (13) working and setting times. In addition, guidelines on luting-agent manipulation are related to available literature and include: (1) temporary cement removal, (2) smear layer removal, (3) powder/liquid ratio, (4) mixing temperature and speed, (5) seating force and vibration, and (6) moisture control. Tables of available products and their properties are also presented together with current recommendations by the authors with a rationale. 相似文献
186.
187.
MF de los Reyes FL de los Reyes M Hernandez L Raskin 《Canadian Metallurgical Quarterly》1998,64(7):2503-2512
Previous studies have shown the predominance of mycolic acid-containing filamentous actinomycetes (mycolata) in foam layers in activated sludge systems. Gordona (formerly Nocardia) amarae often is considered the major representative of this group in activated sludge foam. In this study, small-subunit rRNA genes of four G. amarae strains were sequenced, and the resulting sequences were compared to the sequence of G. amarae type strain SE-6. Comparative sequence analysis showed that the five strains used represent two lines of evolutionary descent; group 1 consists of strains NM23 and ASAC1, and group 2 contains strains SE-6, SE-102, and ASF3. The following three oligonucleotide probes were designed: a species-specific probe for G. amarae, a probe specific for group 1, and a probe targeting group 2. The probes were characterized by dissociation temperature and specificity studies, and the species-specific probe was evaluated for use in fluorescent in situ hybridizations. By using the group-specific probes, it was possible to place additional G. amarae isolates in their respective groups. The probes were used along with previously designed probes in membrane hybridizations to determine the abundance of G. amarae, group 1, group 2, bacterial, mycolata, and Gordona rRNAs in samples obtained from foaming activated sludge systems in California, Illinois, and Wisconsin. The target groups were present in significantly greater concentrations in activated sludge foam than in mixed liquor and persisted in anaerobic digesters. Hybridization results indicated that the presence of certain G. amarae strains may be regional or treatment plant specific and that previously uncharacterized G. amarae strains may be present in some systems. 相似文献
188.
A growth curve analysis was used to examine estimated longitudinal decline (over 19 years) on the Wechsler Adult Intelligence Scale (WAIS; D. Wechsler, 1955) in relation to arterial hypertension and blood pressure (BP) for 55 men and 85 women (40 to 70 years old) who were free from overt major coexisting diseases. BP was associated with longitudinal decline for Visualization-Performance (VP) ability and Speed. Hypertension was a weaker predictor of VP and was unrelated to Speed. Age effects on VP were overestimated when averaged BP level, particularly systolic BP, was not controlled statistically. It was concluded that initial BP level and hypertension predict age-related longitudinal decline in specific major abilities assessed by the WAIS but that BP averaged over examinations is a stronger predictor. 相似文献
189.
DL Smalley JJ Levine DR Shanklin MF Hall MV Stevens 《Canadian Metallurgical Quarterly》1996,196(5):567-574
The current study evaluated immune response to silicon dioxide in children born to women with silicone breast implants. In part one of the study, the T lymphocytes of 21 of 24 such children were significantly stimulated by silicon dioxide (silica). Part two consisted of eleven children, four born preimplantation and seven born postimplantation. None of the preimplant offspring showed T cell responses to silica; five of the seven postimplant children were positive for T cell memory for silica. Part three was a blinded study based on statistically significant differences in T cell stimulation with silicon dioxide between postimplant children and controls. These findings indicate a common immune reaction, that of T cell memory, occurs in mothers and their children born after exposure to silicone mammary implants placed prior to pregnancy. Since not all such children were breast fed the result favors transplacental passage of immunogens such as silicone oligomers or through maternofetal cellular traffic. 相似文献
190.
MF McEntee KN Wright I Wanless R DeVovo JF Schneider R Shull 《Canadian Metallurgical Quarterly》1998,28(2):385-390
Seventy six consecutive patients with T2-4, N0-1, M0 primary breast cancer (BC) received a median of 3 cycles of CMF (cyclophosphamide, methotrexate, 5-fluorouracil) regimen. Tamoxifen was concomitantly administered in patients with estrogen receptor positive (ER+) BC. Ki67 antigen was evaluated immunohistochemically in tumor specimens obtained before chemotherapy and at mastectomy. At post chemotherapy evaluation, tumor shrinkage greater than 50% was obtained in 60 patients (78.9%), 21 of them being complete responders (27.6%). As a whole, primary chemotherapy significantly decreased the number of Ki67 positive cells. More than 50% decrease in Ki67 expression was observed in 78.9% of patients attaining a clinical complete response (CR), in 44.7% of patients with partial remission (PR) and in 50.0% of non-responders, while an increase (>25%) in Ki67 expression was found in 5.3%, 18.4% and 18.7% of patients with CR, PR and non-response, respectively. Both CR and PR rates were superimposable in patients with ER+ and ER- primary BC, while the reduction in Ki67 expression was mainly found in ER+ cases. Patients with increased Ki67 expression from baseline, at the end of primary chemotherapy, had a shorter disease-free interval (70 months) with respect to patients with no change (88+ months) or decrease (87+ months), p<0. 05. To conclude, the activity of CMF + tamoxifen in primary BC does not seem superior to that expected administering CMF alone. The reduction in Ki67 expression, as a whole, correlated with clinical CR, but some individual discrepancies between tumor shrinkage and Ki67 pattern have been observed. The Ki67 reduction mainly confined to the ER+ primary BC suggests that tumor response in this subset may be linked to the reduction in proliferation activity, whereas other mechanisms such as apoptosis might be responsible for the tumor shrinkage in ER- tumors. Since the increase in proliferation activity after primary chemotherapy was associated with a greater recurrence rate and lower disease free interval, irrespective of tumor response, changes in proliferation activity after primary chemotherapy may represent a potentially available parameter that, in addition to the tumor response, can discriminate patients who would benefit from the cytotoxic treatment from patients who would not. 相似文献