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991.
A method for the direct detection of human parvovirus DNA in serum samples that uses a digoxigenin-labeled RNA probe to hybridize with target B19 DNA, followed by capture of the hybrid onto a microtiter plate wells previously coated with a second oligonucleotide probe was developed. The captured hybrid is then detected with anti-digoxigenin-alkaline phosphatase conjugate and chemiluminescent substrate and the reaction read on a scintillation counter. The relative sensitivities of the microwell and standard dot blot hybridization assays were compared. The chemiluminescent microwell hybridization assay was more sensitive than dot-blot hybridization and could be performed in a few hours. This format, therefore, permits rapid and sensitive detection of parvovirus DNA suitable for the clinical setting. 相似文献
992.
AV Lombardi TH Mallory BK Vaughn R Krugel TK Honkala M Sorscher M Kolczun 《Canadian Metallurgical Quarterly》1993,8(6):633-639
From 1981 through 1991, 3,032 primary total knee arthroplasties were performed using the Insall-Burstein Posterior Stabilized Condylar Prosthesis (IB-I, IB-II, and IB-II modified) (Zimmer, Warsaw, IN). Fifteen posterior dislocations occurred: 4 with the IB-I system occurring 2 or more years after surgery, 10 with the IB-II system (8 occurring 6 months after surgery and 2 occurring 2-3 years after surgery), and 1 with the IB-II modified system occurring 9 months after surgery. Statistically significant differences for the rate of dislocation between both the IB-I and IB-II modified arthroplasties versus the IB-II arthroplasties were found (P < .001). In an attempt to identify a cause for these dislocations, the authors retrospectively assessed the 15 dislocated cases with respect to sex, age, weight, height, preoperative and postoperative Hospital for Special Surgery scores, preoperative and postoperative alignment, preoperative versus postoperative reconstruction dimensions, patellar thickness and height, and postoperative flexion and compared the results with those patients who did not experience dislocation. Possible etiologies and mechanisms of dislocation were sought. There were no significant differences between the control and study groups for any variable assessed, with the exception of postoperative flexion, which averaged 118 degrees for the study group and 105 degrees for the control group (P < .001). Conservative management was successful in 11 cases. In September 1988 the IB-II system was introduced; modification of the tibial insert was made in January 1990.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
Glutathione has been implicated to function in cytoprotection against cadmium toxicity. The mechanism by which glutathione plays this role has not been well understood. Because glutathione is an important antioxidant and several studies have shown that cadmium induces oxidative stress, this study was undertaken to determine whether development of cadmium resistance is linked to enhanced antioxidant activities. A cadmium-resistant subpopulation of human lung carcinoma A549 cells, which was developed by repeatedly exposing the cells to step-wise increased cadmium concentrations, was compared to a cadmium-sensitive one. The acquired cadmium resistance resulted from neither decreased cadmium uptake nor enhanced cellular metallothionein synthesis. Glutathione content, however, was markedly elevated in the cadmium-resistant cells. In contrast, the activities of the glutathione redox cycle related enzymes, glutathione peroxidase and reductase, were unchanged. Two other antioxidant enzymes, superoxide dismutase and catalase, were also not altered. The results suggest that the development of cadmium resistance in A549 cells unlikely results from enhanced antioxidant enzyme activities, although it is associated with elevated cellular glutathione levels. In addition, measurement of the mRNA and DNA levels for gamma-glutamylcysteine synthetase, the rate-limiting enzyme for glutathione biosynthesis, revealed that enhanced expression of the enzyme but not gene amplification is likely responsible for the elevation of cellular glutathione levels. 相似文献
994.
R Valentino S Savastano AP Tommaselli MT Scarpitta M Dorato M Gigante E Calvanese M Carlino G Lombardi 《Canadian Metallurgical Quarterly》1997,20(11):690-694
A normal gonadal maturation with normal fertility are some of the major goals of long-term replacement therapy in adult males with Congenital Adrenal Hyperplasia (CAH). We describe here two young men, G.O. (case A, 23 years old) and S.S.(case B, 24 years old), both with a well defined diagnosis of CAH due to 21-hydroxylase deficiency classic homozygote form (21-CAH). In case A the diagnosis of the 21-CAH classic virilizing form was made at 3 years of age. The patient has undergone glucocorticoid therapy and is now 170 cm tall; all his hormonal findings are within the normal range. The semen analysis has shown a good fertility potential, with a slight modification when the patient decided to discontinue the therapy. In case B the diagnosis of the 21-CAH salt wasting form was performed at 9 days of age. The patient was initially treated with i.v. normal saline solution and a daily i.m. injection of hydrocortisone and, subsequently, with mineral and glucocorticoid replacement therapy po. A satisfactory adult stature (165 cm) was attained. The patient is still on therapy, with a good hormonal profile. The semen analysis has shown an apparently normal fertility. In conclusion, our experience in adult males with 21-CAH, who have been administered prompt and adequate replacement therapy, shows that these patients can attain normal quality of life, satisfactory growth and development, normal sexual maturation and activity, and adequate sperm fertilizing ability, thereby supporting the usefulness of continuing this therapy during adult age. 相似文献
995.
Driss EL Allam Marcelle Gaune-Escard Jean-Pierre Bros Erhard Hayer 《Metallurgical and Materials Transactions B》1995,26(4):767-773
Enthalpies of formation of (Pd + In) alloys have been obtained by direct reaction calorimetry using a very high temperature
calorimeter between 1425 and 1679 K in the concentration range 0 <x
Pd < 0.66. They are very negative with a minimum Δmix
H
o
m, = -59.6 /2.5 kJ · mol-1 atx
Pd = 0.59 and independent of temperature within the experimental error. The integral molar enthalpy of mixing is given by ΔmixΔH
m
o
/· mol-1 =x(1 -x)·- (-126.94 - 92.653x-83.231.x
2 - 734.49.x
3 + 949.07x
4), wherex = x
Pd. The limiting partial molar enthalpy of palladium in indium was calculated as Δh
m(Pd liquid in ∞ liquid In) = -127 ± 5 kJ·mol-1. The results are discussed and compared with the enthalpies of formation of solid alloys. The anomalous behavior of the partial
enthalpy of Pd is assumed to be due to the charge transfer of, at most, two electrons of In to Pd.
Formerly Ph.D. Student, Université de Provence. 相似文献
996.
We studied the post-resuscitation syndrome in 42 healthy dogs after normothermic ventricular fibrillation cardiac arrest (no blood flow) of 7.5, 10, or 12.5 min duration, reversed by standard external cardiopulmonary resuscitation (CPR) (< or = 10 min) and followed by controlled ventilation to 20 h and intensive care to 72 h. We reported previously, in the same dogs, no difference in resuscitability, mortality, or neurologic outcome between the three insult groups. There was no pulmonary dysfunction, but post-arrest cardiovascular failure, of greater severity in the 12.5 min arrest group. This report concerns renal, hematologic, hepatic and bacteriologic changes. Renal function recovered within 1 h after arrest, without permanent dysfunction. Clotting derangements at 1-24 h postarrest reflect transient disseminated intravascular coagulation with hypocoagulability, more severe after longer arrests, which resolved by 24 h after arrest. Hepatic dysfunction was transient but more severe in the animals that did not recover consciousness and correlated with neurologic dysfunction, but not with brain histologic damage. Bacteremia was present in all animals postarrest. We conclude that in the previously healthy organism after cardiac arrest of 7.5-12.5 min no flow, visceral and hematologic changes, although transient, can retard neurologic recovery. 相似文献
997.
MZ Wamboldt G Fritz A Mansell EL McQuaid RB Klein 《Canadian Metallurgical Quarterly》1998,37(9):943-950
OBJECTIVE: To determine whether physiological severity of asthma is associated with increased psychological symptoms in children. METHOD: Participants were 337 children, aged 7 to 19 years (mean 11.9, SE 0.13), and a parent of each child. Children's asthma severity was rated by experienced pediatric asthma specialists using current guidelines from the National Heart, Lung, and Blood Institute. Children filled out the Children's Manifest Anxiety Scale and the Weinberger Adjustment Inventory. Parents reported on their child's medical history, completed the Child Behavior Checklist (CBCL) about their child, and completed the Pennebaker Inventory of Linguid Languidness as a measure of their own physical symptoms. RESULTS: Child-rated anxiety symptoms were unrelated to asthma severity or to markers of asthma functional morbidity. Parental ratings of internalizing symptoms in their children were related to severity. Parent physical symptoms explained 10.2% of the variance in CBCL Internalizing symptoms, and asthma severity added an additional 6.7% to the variance. CONCLUSIONS: Asthma severity may be a more salient stressor to parents, who in turn report higher levels of child internalizing symptoms for children with severe asthma, than to children themselves. Contrary to prior hypotheses, children with severe asthma did not rate themselves as having higher levels of anxiety than those with mild or moderate asthma or than standardized norms. 相似文献
998.
999.
EC Chan J Falconer G Madsen KC Rice EL Webster GP Chrousos R Smith 《Canadian Metallurgical Quarterly》1998,139(7):3357-3360
In sheep, corticotropin-releasing hormone (CRH) can stimulate the fetal release of ACTH to produce a cortisol surge which leads to the onset of parturition. We tested the hypothesis that fetal CRH is a primary factor in the onset of parturition in sheep by using a Type I CRH receptor antagonist, antalarmin, to block the endogenous action of CRH. Pregnant ewes were cannulated at 130-135 days of gestation. Five catheters were placed into the amniotic sac, fetal femoral artery, fetal tarsal vein, maternal jugular vein and carotid artery. After 5 days' recovery, blood samples from maternal and fetal vessels were collected at the following times: a day before the start of infusion, at [-1, 0, 1, 2, 4, 8 and 24]h, on the first day of infusion, and thereafter daily throughout a 10-day infusion. Animals (n=6 per group) received infusions into a fetal vein of either a vehicle comprising 1:1 mixture of ethanol and polyethoxylated castor oil (Cremophor EL) or antalarmin (50 g/L) in the vehicle at a rate of 0.3 mL/h. The plasma samples were assayed for ACTH and cortisol using commercial RIA kits. Fetuses infused with vehicle delivered at a mean gestational age of 141.8 +/- 0.9 days compared with antalarmin-infused sheep at 148.8 +/- 1.6 days (P = 0.0036, unpaired Student's t-test). Fetal ACTH and cortisol did not change in the antalarmin-infused sheep after 3 days' infusion compared to significant increases in vehicle-infused sheep (P=0.004 and P = 0.016 respectively, ANOVA). These data show that CRH receptor antagonism in the fetus can delay the onset of parturition. It supports the hypothesis that hypothalamic CRH drives fetal production of ACTH and is essential for the onset of parturition triggered by a surge in fetal cortisol. 相似文献
1000.
IuS Martynov TI Girich GI Kuntsevich EL Sokov EV Malkova NF Borisova NV Nozdriukhina NA Shuvakhina 《Canadian Metallurgical Quarterly》1998,98(8):14-18
1. Although decreasing the use of seclusion and restraints in the management of aggressive children is a critical issue facing pediatric psychiatric inpatient programs, finding effective alternatives has been a difficult challenge. 2. Therapeutic holding appears to be as effective as seclusion and restraint with respect to managing aggressive behaviors in the psychiatrically disordered child. 3. Therapeutic holding has the potential to reduce the episodes of mechanical restraints and to be perceived by children as less punitive. 相似文献