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81.
Surgical correction of a hallux valgus deformity is common among podiatric and orthopedic surgeons. Complications following hallux valgus surgery are not uncommon. Although many of these complications can be avoided by a comprehensive understanding of the pathomechanics of a hallux valgus deformity and continual honing o surgical skills, some are inevitable. This article provides a comprehensive overview and insight into the diagnosis and treatment of the more common complications encountered with hallux valgus surgery.  相似文献   
82.
OBJECTIVE: To investigate the relation between suboptimal intrapartum obstetric care and cerebral palsy or death. DESIGN: Case-control study. SETTING: Oxford Regional Health Authority. SUBJECTS: 141 babies who subsequently developed cerebral palsy and 62 who died intrapartum or neonatally, 1984-7. All subjects were born at term of singleton pregnancies and had no congenital anomaly. Two controls, matched for place and time of birth, were selected for each index case. MAIN OUTCOME MEASURES: Adverse antenatal factors and suboptimal intrapartum care (by using predefined criteria). RESULTS: Failure to respond to signs of severe fetal distress was more common in cases of cerebral palsy (odds ratio 4.5; 95% confidence interval 2.4 to 8.4) and in cases of death (26.1; 6.2 to 109.7) than among controls. This association persisted even after adjustment for increased incidence of a complicated obstetric history in cases of cerebral palsy. Neonatal encephalopathy is regarded as the best clinical indicator of birth asphyxia; only two thirds (23/33) of the children with cerebral palsy in whom there had been a suboptimal response to fetal distress, however, had evidence of neonatal encephalopathy; these 23 formed 6.8% of all children with cerebral palsy born to residents of the region in the four years studied. CONCLUSION: There is an association between quality of intrapartum care and death. The findings also suggest an association between suboptimal care and cerebral palsy, but this seems to have a role in only a small proportion of all cases of cerebral palsy. The contribution of adverse antenatal factors in the origin of cerebral palsy needs further study.  相似文献   
83.
Elevated plasminogen activator inhibitor-1 (PAI-1) and fibrinogen concentrations are risk factors for coronary heart disease. We investigated environmental, familial, and genetic influences on PAI-1 antigen and fibrinogen concentrations in 2029 adults from 512 randomly ascertained families in 4 US communities. We used maximum-likelihood segregation analysis to fit several genetic and nongenetic modes of inheritance to the data to determine whether mendelian inheritance of a major gene could best explain the familial distributions of these 2 hemostatic factors. Age- and gender-adjusted familial correlations for PAI-1 antigen level averaged 0.16 in first-degree relatives (95% CI=0.11 to 0.21); the spouse correlation was positive but not statistically significant (r=0.10, 95% CI=-0.02 to 0.23). Complex segregation analysis indicated a major gene associated with higher PAI-1 concentrations in 65% of individuals from these families. Demographic, anthropometric, lifestyle, and metabolic characteristics together explained 37% to 47% of the variation in PAI-1 antigen levels, and the inferred major gene explained an additional 17% of the variance. Positive and statistically significant age- and gender-adjusted familial correlations in first-degree relatives indicated a possible heritable component influencing plasma fibrinogen concentration (r=0. 17, 95% CI=0.13 to 0.22); however, segregation analysis did not provide statistical evidence of a major gene controlling fibrinogen level. These family data suggest that there are modest familial and genetic effects on the concentration of PAI-1.  相似文献   
84.
Several physical properties of creatine kinase (EC 2.7.3.2) isozymes MM (CK-MM, muscle-type) and BB (CK-BB, brain-type), both homodimers, and isozyme MB (CK-MB), a heterodimer, were compared to determine how formation of the hybrid modifies subunit conformation and dynamics. Circular dichroic spectra revealed additional alpha-helical content for the hybrid isozyme. Double-beam absorption difference spectra between CK-MB and a stoichiometric mixture of CK-MM and CK-BB revealed decreased exposure of intrinsic chromophores in the hybrid. The relative intensity of the intrinsic fluorescence of CK-MB was between the two homodimers, but was 16% closer to the less fluorescent CK-MM. Steady state anisotropy spectra and decay of the anisotropy of CK derivatized on a single subunit with the fluorescent sulfhydryl reagent 5-[2-(iodoacetyl)amino-ethyl]aminonaphthalene-1-sulfonate indicated that the derivatized sites are more flexible in the heterodimer. The slow component in the anisotropy decay suggests that hybridization results in a small increase in the packing density or contraction of overall conformation of the B-subunit. The KM for MgATP with singly derivatized CK-MB was the same as the KM for the native enzyme. However, derivatization of a single subunit caused the Vmax to decrease by greater than 50%, which indicates that subunit-subunit interactions may modulate the activity of CK. A model for assembly of CK-MB is proposed which includes subunit characteristics more similar to those found in the muscle-type homodimer than in the brain-type homodimer and increased flexibility of the active site domain of both subunits.  相似文献   
85.
Drug craving, the desire to re-experience the effects of a psychoactive substance, may be an important influence on drug-seeking and drug-taking behaviour. In rats, drug-seeking behaviour can be operationalized as conditioned anticipatory behaviour, evidenced by frequent visits to, and an increased time spent and distance travelled in, the drug administration area prior to the availability of the reinforcer. The effects of the opioid antagonist, naltrexone, and its derivatives, nalmefene and naltrindole, on conditioned anticipatory behaviour and drinking-associated behaviour and fluid intake during the access phase were examined. Male Wistar rats were trained to consume 0.1% saccharin and water in a distinct environment in a free-choice limited-access procedure. Naltrexone (0.3, 1 mg/kg) decreased conditioned anticipatory behaviour and drinking-associated behaviour in the saccharin zone without affecting the corresponding behaviour in the water zone. Its derivatives had different effects. Nalmefene (0.1 mg/kg) increased drinking-associated behaviour but not conditioned anticipatory behaviour, whereas naltrindole (1, 2 mg/kg) modestly decreased conditioned anticipatory behaviour but not drinking-associated behaviour. Naltrexone (0.3, 1 mg/kg) and naltrindole (1, 2 mg/kg), but not nalmefene, selectively decreased saccharin intake. These findings suggest that the blockade of selective opioid receptors may differentially alter conditioned anticipatory behaviour, drinking-associated behaviour and consumption levels, and that these behaviours can be modified separately.  相似文献   
86.
In this article the authors report the findings of a 2-year study evaluating the effectiveness of REACH OUT, a train-the-trainer program developed to assist small businesses comply with California legislation, Senate Bill 198 (1989), requiring employers to implement a worksite Injury and Illness Prevention Program. Data from a case study sample of 8 companies, drawn from 151 Southern California small businesses participating in the larger study, are reported. Diagnostic walk-throughs were performed, and employee surveys collected at the case study companies approximately 2 months before the treatment group received the intervention and again I year later. Results indicate that greater corporate compliance led to employees' perceptions of increased health and safety meetings and training sessions, which led to greater employee health and safety knowledge and improved employee health outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
A 4 1/2-month-old male infant with systemic candidiasis had anuria secondary to Candida albicans fungus balls impacted in the renal pelves. The patient was treated with temporary urinary diversion, amphotericin B, and flucytosine. Six weeks after therapy had been concluded, the patient had C albicans arthritis of the right hip and responded to a second course of amphotericin B and flucytosine therapy. This article discusses immunologic evaluation and presents a literature review.  相似文献   
88.
In 38 patients with glomerulo- (20 patients) and pyelonephritis the renal blood flow was measured with radioxenon. Despite normal creatinine clearance in chronic diseases the blood flow is already reduced. The correlation to the creatinine clearance is loose. In glomerulonephritis above all a reduction of the blood flow of the cortex appears, in pyelonephritis the participation of the cortex is reduced. Correlations of blood circulation and blood pressure are to be found in no stage of the disease. Concerning the renal insufficienzy there does not exist a disease-specific pattern of blood flow. In renal insufficiency the diuresis is independent of blood flow.  相似文献   
89.
Changes in buccal and opercular pressure amplitude, as well as ventilation and coughing frequency were monitored in rainbow trout using catheterization of respiratory cavities and pressure transducers. One or more of the ventilatory parameters measured were found to change under toxicant stress at concentrations of copper or zinc at or below the LC 50. Possible synergistic effects were indicated when the two metal ions were tested together.Serial analyses of arterial PO2 and pH in fish exposed to copper and zinc individually at concentrations approximating the LC 50 showed that environmental zinc produced a sharp decrease in both PO2 and pH. Copper, however, caused little effect other than a transient increase in pH. The toxic action of the two metals in low concentrations thus may not be the same.  相似文献   
90.
随着微电子机械系统新应用的不断推出,使得特殊制造工艺技术得到空前的发展。在过去的10年里,汽车是微电子机械系统产品商业化的推动力。如今,我们进入了以消费品和信息技术的产品占很高份额的微电子机械系统生产制造的新时代,如微射流器件,微光电子机械系统,射频微电子机械系统,非汽车应用加速度器和陀螺等。阐述用于商业化的如上所述器件的新制造工艺技术,即用全自动轨道传送光刻系统来实现低成本的紫外线光刻工艺,以及用于加速度器和陀螺等消费品的高真空键合制造工艺技术。  相似文献   
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