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121.
FD Battistella SZ Torabian KM Siadatan 《Canadian Metallurgical Quarterly》1997,42(6):1012-6; discussion 1016-7
BACKGROUND: Outpatient complications leading to hospital readmission after hospitalization for trauma have not been examined. METHODS: A retrospective chart review of all trauma victims admitted to a Level 1 trauma center from January of 1990 to January of 1995 was performed to characterize patients who required readmission after hospitalization for trauma. Risk factors for readmission were determined by stepwise regression analysis. RESULTS: Of 15,463 trauma admissions, 209 patients (1.4%) required readmission, 84% within 30 days, 71% within 14 days. Reasons for readmission included wound (29%), abdominal (29%), pulmonary (18%), and thromboembolic (19%) complications. Fifty of the patients (24%) readmitted with a complication required an operation. Risk factors for readmission included: operation during first hospitalization (p < 0.0001), penetrating injury (p = 0.0001), and advanced age (p = 0.0001). Injury Severity Score, length of hospitalization, and gender were not independent predictors of readmission. CONCLUSIONS: Outpatient complications leading to readmission after hospitalization for trauma are not common; however, many are serious and require operative intervention. Because most complications were identified by the second week after discharge, outpatient follow-up visits should be scheduled within 7 to 14 days. Based on our findings, we recommend protocols be established to ensure follow-up for trauma patients, especially those who have had an operation, were victims of penetrating injury, or those > 65 years of age. 相似文献
122.
SZ Whetzel YH Shih LM Georgic HC Akunne TA Pugsley 《Canadian Metallurgical Quarterly》1997,69(6):2363-2368
The dopamine (DA) D3 receptor antagonist PD 58491 [3-[4-[1-[4-[2-[4-(3-diethylaminopropoxy)phenyl]benzoimidazol++ +-1-yl-butyl]-1H-benzoimidazol-2-yl]phenoxy]propyl]diethylamine] bound with high affinity and selectivity to recombinant human DA D3 versus D2L and D4.2 receptors transfected into Chinese hamster ovary cells: Ki values of 19.5 nM versus 2,362 and >3,000 nM, respectively. In contrast, the putative DA D3 receptor antagonist (+)-AJ76 displayed low affinity and selectivity for D3 versus D2L and D4.2 receptors (91 nM vs. 253 and 193 nM, respectively). In vitro, PD 58491 (1 nM-1 microM) exhibited D3 receptor antagonist activity, reversing the quinpirole (10 nM)-induced stimulation of [3H]thymidine uptake in D3 CHOpro-5 cells, but did not have any significant intrinsic activity by itself in this assay. PD 58491 did not decrease the gamma-butyrolactone-induced increase in DA synthesis (L-3,4-dihydroxyphenylalanine accumulation) in rat striatum, indicating that the compound possessed no in vivo DA D2/D3 receptor agonist action at DA autoreceptors. PD 58491 (3-30 mg/kg, i.p.) generally did not alter DA or serotonin synthesis in either the striatum or mesolimbic region of rat brain. The D3-preferring agonist PD 128907 decreased DA synthesis in striatum and mesolimbic regions, and this effect was attenuated by pretreatment with PD 58491. These findings support the hypothesis that DA D3 autoreceptors may in part modulate the synthesis and release of DA in striatum and mesolimbic regions. 相似文献
123.
AIM: The neonatal resuscitation program (NRPG) was first introduced in our hospital to replace the traditional resuscitation (TR) program in 1993. TR has been in existence in China for a long time. The implementation of NRPG was timely in reducing the number of infant mortality and also to disseminate to the many hospitals in China which are still practising TR. METHOD: A perspective study of 4,751 newborns with 366 asphyxiated babies in a period of 2 years was carried out. A previous sample of 1,722 live births under the TR program was compared as a controlled group statistically. RESULTS: From August 1993 to August 1995, when NRPG was exclusively implemented in our hospital, only 16 newborns died within 7 days, out of 4,751 births (3.4%) with 2 deaths in the delivery room. Seventeen newborns died within 7 days out of 1,722 births (9.9+) in the TR group, with 10 deaths in the delivery room. From the data shown, it can be clearly seen that perinatal neonatal mortality rate was reduced almost 3 times after NRPG was implemented (chi(2) = 10.54, p < 0.01). The follow-up results of 21 cases of severe asphyxia at 2 months--1 year of age were normal except for one with cerebral palsy. CONCLUSIONS: Our study showed that NRPG was indeed a very effective and feasible technique during the delivery process in the reduction of neonatal mortality. It is important to disseminate widely the knowledge and technique of NRPG in places where TR is still being widely practiced especially in developing countries. 相似文献
124.
SZ Domanico AJ Pelletier WL Havran V Quaranta 《Canadian Metallurgical Quarterly》1997,8(11):2253-2265
It is well established that integrins and extracellular matrix (ECM) play key roles in cell migration, but the underlying mechanisms are poorly defined. We describe a novel mechanism whereby the integrin alpha 6 beta 1, a laminin receptor, can affect cell motility and induce migration onto ECM substrates with which it is not engaged. By using DNA-mediated gene transfer, we expressed the human integrin subunit alpha 6A in murine embryonic stem (ES) cells. ES cells expressing alpha 6A (ES6A) at the surface dimerized with endogenous beta 1, extended numerous filopodia and lamellipodia, and were intensely migratory in haptotactic assays on laminin (LN)-1. Transfected alpha 6A was responsible for these effects, because cells transfected with control vector or alpha 6B, a cytoplasmic domain alpha 6 isoform, displayed compact morphology and no migration, like wild-type ES cells. The ES6A migratory phenotype persisted on fibronectin (Fn) and Ln-5. Adhesion inhibition assays indicated that alpha 6 beta 1 did not contribute detectably to adhesion to these substrates in ES cells. However, anti-alpha 6 antibodies completely blocked migration of ES6A cells on Fn or Ln-5. Control experiments with monensin and anti-ECM antibodies indicated that this inhibition could not be explained by deposition of an alpha 6 beta 1 ligand (e.g., Ln-1) by ES cells. Cross-linking with secondary antibody overcame the inhibitory effect of anti-alpha 6 antibodies, restoring migration or filopodia extension on Fn and Ln-5. Thus, to induce migration in ES cells, alpha 6A beta 1 did not have to engage with an ECM ligand but likely participated in molecular interactions sensitive to anti-alpha 6 beta 1 antibody and mimicked by cross-linking. Antibodies to the tetraspanin CD81 inhibited alpha 6A beta 1-induced migration but had no effect on ES cell adhesion. It is known that CD81 is physically associated with alpha 6 beta 1, therefore our results suggest a mechanism by which interactions between alpha 6A beta 1 and CD81 may up-regulate cell motility, affecting migration mediated by other integrins. 相似文献
125.
126.
M Hu N Brasseur SZ Yildiz JE van Lier CC Leznoff 《Canadian Metallurgical Quarterly》1998,41(11):1789-1802
A series of benzyl-substituted phthalonitriles, substituted at the 3-, 4-, and 4,5-positions, underwent varied condensations with phthalonitrile to give a series of protected (monohydroxy- and polyhydroxyphthalocyaninato)zinc(II) derivatives which were readily cleaved to give several hydroxyphthalocyanines (ZnPc) (phthalocyanine phenol analogues). Their efficacy as sensitizers for the photodynamic therapy (PDT) of cancer was evaluated on the EMT-6 mammary tumor cell line. In vitro, the 2-hydroxy ZnPc (32) was the most active, followed by the 2,3- and 2,9-dihydroxy ZnPc (39 and 45), with the 2,9,16-trihydroxy ZnPc (33) exhibiting the least activity. In vivo, the monohydroxy derivative 32 and the 2,3-dihydroxy derivative 39 were both efficient in inducing tumor necrosis at 1 micromol kg-1, but complete tumor regression was poor, even at 2 micromol/kg. In contrast, the 2,9-dihydroxy isomer 45, at 2 micromol kg-1, induced tumor necrosis in all animals treated, with 75% complete regression. These results underline the importance of the position of the substituents on the Pc macrocycle to optimize tumor response and confirm the PDT potential of the unsymmetrical Pcs bearing functional groups on adjacent benzene rings. 相似文献
127.
TA Rugsley MD Davis HC Akunne LW Cooke SZ Whetzel RG MacKenzie YH Shih DH van Leeuwen SB DeMattos LM Georgic 《Canadian Metallurgical Quarterly》1995,274(2):898-911
The receptor binding and biochemical effects of the putative dopamine (DA) partial agonist CI-1007 ([R(+)-1,2,3,6-tetrahydro-4-phenyl- 1-[(3-phenyl-3-cyclohexen-1-yl)methyl]pyridine] maleate) and potential antipsychotic were evaluated with a variety of biochemical methods. In receptor binding studies, CI-1007 bound to rat striatal DA receptors exhibiting a Ki of 3 nM as assessed by inhibition of [3H]N-propylnorapomorphine binding. CI-1007 also exhibited high affinity for cloned human D2L (Ki = 25.5 nM) and D3 (Ki = 16.6 nM) receptors with less affinity for D4.2 receptors (Ki = 90.9 nM). The affinity for serotonin-1A (5-HT-1A), alpha-2 adrenergic and 5-HT-2 receptors was moderate (submicromolar range) and slight or negligible for alpha-1, DA D1 and various other receptors. Unlike dopamine, the inhibition of [3H]spiperone binding was monophasic for CI-1007 and only slightly affected by the addition of Gpp-(NH)p. In vitro CI-1007 antagonized the forskolin-induced increases in cyclic AMP levels in GH4C1 cells expressing the human D2L receptor, having an intrinsic activity of 53% of that seen with the full agonist quinpirole. In vivo CI-1007 antagonized the gamma-butyrolactone (GBL)-induced accumulation of L-3,4-dihydroxyphenylalanine in striatum and mesolimbic regions of rat brain, causing a maximal 64% reversal in striatum, consistent with a partial agonist profile. In microdialysis studies it decreased DA overflow in both striatum and nucleus accumbens, indicating decreased release of DA. CI-1007 also reduced brain DA synthesis (DOPA accumulation), metabolism (DOPAC and HVA) and utilization (after tyrosine hydroxylase inhibition with alpha-methyl-p-tyrosine). CI-1007 did not affect striatal acetylcholine levels indicating lack of potent postsynaptic DA actions. CI-1007 seemed to be selective for DA neurons as it did not alter rat brain norepinephrine (NE) synthesis in the NE-enriched brainstem or NE utilization in the mesolimbic region. In addition, it did not affect in general 5-HT synthesis and metabolism in striatum and mesolimbic regions. These neurochemical results demonstrate that CI-1007 is a selective potent brain dopamine partial agonist with limited agonist activity at postsynaptic DA receptors. 相似文献
128.
We evaluated seven patients with oral motor apraxia and ocular motor apraxia. Apraxia in three patients (Group 1) with new-onset partial seizures and epileptiform discharges on EEG improved with carbamazepine. Four patients (Group 2) without seizures and nonepileptiform EEG findings had no change in apraxia after a trial of carbamazepine. Epileptic apraxia may precede clinical seizures and can respond to antiepileptic drugs. 相似文献
129.
SZ Alvarez 《Canadian Metallurgical Quarterly》1998,13(8):833-839
Comparative genomic hybridization (CGH) has been proven to be an important tool in interphase cytogenetics of solid tumors. Although, because of methodological implications, balanced aberrations are not detected by CGH, the technique has uncovered a variety of new and interesting imbalanced karyotype changes. However, only a few studies deal with its application to hematologic disorders, although this is a main topic of cytogenetics. The aim of our study was, therefore, to evaluate the usefulness of CGH in the examination of hematologic neoplasms. For this purpose, bone marrow aspirates of 33 patients with different hematologic disorders were examined with CGH and the results compared with conventional cytogenetics (CC) and fluorescence in situ hybridization (FISH). CGH showed chromosome changes in 8 of 33 cases. CC found balanced aberrations in 4 of 33 and unbalanced changes in 9 of 33 samples. Differences between CGH and CC in unbalanced aberrations were seen in four cases. In these samples, either the number of aberrant cells found by CC was low and, therefore, difficult to detect by CGH, or complex aberrations in different cell clones as seen in CC were lumped together as one karyotype by CGH. In one sample, CC was not capable of giving any results at all, whereas CGH showed trisomy 8. CGH was also helpful in defining the bands involved in the structural aberrations, which was difficult by CC in some cases because of the low quality of metaphase spreads. All results obtained by CGH were confirmed by FISH, whereas CC and FISH were discordant in one case. Although CGH was not able to detect all aberrations, it gave important additional information for the correct localization of the aberrations found in CC, and it was most helpful in samples not processed successfully in CC. These advantages would open up a new field of application for CGH not only for research, but also for diagnostic purposes. 相似文献
130.
Little is known about the effects of intentional weight loss on the function of the hypothalamic-pituitary-adrenal (HPA) axis of obese individuals. We studied the HPA axis of 34 healthy obese women (body mass index, 40.2 +/- 7.9 kg/m2) before and after a 21.0 +/- 7.9-kg weight loss induced by a 26-week weight loss program that included 12 weeks of a 3350 kJ/day (800 Cal/day) liquid formula diet, 6 weeks of gradual refeeding, and 6 weeks of caloric stabilization at 5020-6280 kJ/day (1200-1500 Cal/day). Obese subjects were evaluated twice: before caloric restriction and during the last 3 weeks of caloric stabilization with a 3-h evening 1 microg/kg ovine CRH (oCRH) stimulation test. CRH-stimulated ACTH and cortisol values were compared to those of a control group of 12 normal weight women. Before caloric restriction, both ACTH and cortisol responses to oCRH were similar in obese women and normal weight controls. Weight loss did not significantly alter the ACTH response to oCRH; however, the total plasma cortisol response to oCRH decreased significantly with weight loss (area under the curve, 96,320 +/- 21,040 nmol/L x min before weight loss; 82,450 +/- 22,460 nmol/L x min after weight loss; P < 0.001). Cortisol-binding globulin also decreased significantly after weight loss (2,270 +/- 1,050 nmol/L) compared either to values obtained before weight loss (3,590 +/- 1,360 nmol/L; P < 0.001) or to those of normal weight controls (3,910 +/- 1,400 nmol/L; P < 0.001). Assay for plasma free cortisol, either before or 180 min after oCRH treatment, showed no significant changes in cortisol responses resulting from weight loss. As plasma free cortisol was not altered by weight reduction, the decrease in the total cortisol response to oCRH after weight loss appears to be secondary to significant decreases in cortisol-binding globulin. We conclude that when obese women lose large amounts of weight with a 3350 kJ/day, very low energy diet, such weight reduction does not significantly affect the HPA axis. 相似文献