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81.
A consecutive series of 117 patients treated for hip fracture were followed up prospectively for three years. The mortality was highest during the first year. The proportion living in nursing-homes was increased by 50% at one year and 25% at three years compared with before injury, but the absolute numbers were reduced because of mortality. Reduced pre-injury mobility greatly increased the risk of becoming institutionalized. The proportion of the survivors who walked without aids was reduced by more than half at one and three years. The proportion of those bedridden increased six fold. Among patients who walked without aids before fracture 31% needed two sticks or more and 7% were bedridden after one year. Among those who before fracture walked with one stick or more, the percentages were 91 and 43.  相似文献   
82.
The single-stranded DNA parvoviruses occur in humans and many species of animals. In general, they are species-specific and capable of producing disease at any stage of life. Parvoviruses have a requirement to replicate in cells in a permissive S-phase of DNA mitosis. The infections may be cytolytic to select cell groups resulting in specific developmental defects or may produce more generalized effects such as anemia, pancytopenia, or hemorrhage. The fetus is at particular risk for damage because of the vast number of cells in active mitosis. The teratogenic effects may be severe, often resulting in fetal death. Infections in childhood and adulthood are more frequently mild to subclinical. Some of the teratogenic effects recognized in animal species have been identified in humans. With increased knowledge of parvovirus effects in animals, more pathogenic effects may be related to human parvoviral disease. The need for vaccination, currently used annually in many domestic animal species, continues to be evaluated for humans.  相似文献   
83.
The aims of this study were to analyze the characteristics of craniofacial structure in normal occlusion and to assess the relationship between the skeletal and occlusal pattern. Fifty-seven subjects with normal occlusion were divided into three skeletal groups according to Hauston measurement. One hundred and sixty-six subjects with Angle's malocclusion were also classified according to ANB values. The result showed that there were significant differences in the values of NA-APg, AB-NPg, SNA, SNB, U1-NA, L1-NB among the three groups. These data indicate that skeletal pattern does not coincide with occlusion. Different skeletal pattern exists even in normal occlusion. In diagnosis and treatment planning, the data of skeletal pattern should be referred.  相似文献   
84.
BACKGROUND: In dealing with displaced proximal humerus fractures, there is still much controversy in treatment modalities. The latest investigations emphasize the concept of minimal exposure and rigid fixation. METHODS: The technique of closed reduction and percutaneous fixation with cannulated screws and k-pins was performed on 19 patients with two- and three-part proximal humerus fractures. The outcomes were evaluated with a mean follow-up of 21 months. RESULTS: All except one case had a solid union of the fracture. Sixteen of 19 patients (84%) acquired good or excellent results according to Neer's classification. No further collapse or avascular necrosis was found. CONCLUSION: The method of closed reduction and percutaneous fixation, although technically demanding, yields satisfactory results in displaced proximal humerus fracture. Cannulated screws provided rigid fixation that was the underlying tenet for early functional retrieval.  相似文献   
85.
Dysphagia is related to the impairment of food passage from the mouth to the stomach. Globus pharyngis implies the frequent and often painful sensation of a lump in the throat that usually does not interfere with swallowing and may even be relieved by food intake. The diagnosis is based upon a careful history, clinical examination, endoscopy, dynamic imaging (videofluoroscopy, cinematography, videosonography) and electrophysiologic procedures (including pharyngoesophageal manometry, electromyography and pH determinations). Structural lesions of the cervical spine such as diffuse idiopathic skeletal hyperostosis are rare causes of dysphagia. Dysphagia following anterior cervical fusion as well as globus and dysphonia due to dysfunction of the vertebral joints are more likely. Symptoms with swallowing fluids indicate a neurogenic origin. Dyscoordinated swallowing, nasal reflux, dysphonia or general weakness may also occur. Chronic aspiration with respiratory compromize is the main consequence in a variety of neurological disorders as well as in cases of postsurgical dysphagia. Relaxation of the upper esophageal sphincter indicates coordinated muscle movement between the pharynx and esophagus. Dysfunction of the pharyngoesophageal segment may lead to cricopharyngeal achalasia. A dyskinetic sphincter commonly represents an extrapharyngeal cause: i.e., disease associated with gastroesophageal reflux. Disorders of the esophageal phase of deglutition can produce retrosternal pain, heartburn, regurgitation and vomiting, as well as laryngeal and respiratory signs. Esophageal motility disorders include lower achalasia, tumors, peptic strictures, inflammatory diseases, drug-induced ulcers, rings and webs. Motility disorders present with aperistaltic, spontaneous contractions, diffuse esophagospasm, or a hypermotile esophagus. Gastroesophageal reflux with esophagitis must always be excluded, especially in patients with a globus sensation. The multiple features of the appearance of the symptoms of dysphagia and globus makes multidisciplinary approach necessary in order to establish a diagnosis and begin effective treatment.  相似文献   
86.
We describe the in vivo phenotypes associated with three genomic intervals containing systemic lupus erythematosus (SLE)-susceptibility genes derived from the SLE-prone NZM2410 strain on a C57BL/6 genome. These intervals were identified previously via a genome-wide analysis of SLE susceptibility in a (NZM2410 x C57BL/6)F1 x NZM2410 backcross, and transferred independently on a C57BL/6 background to produce three congenic strains: B6.NZMc1 carrying Sle1, B6.NZMc4 carrying Sle2, and B6.NZMc7 carrying Sle3. B6.NZMc1 develops high titers of IgG anti-nuclear autoantibodies in the absence of any severe nephritis. B6.NZMc4 spontaneously develops elevated levels of IgM, but not IgG Abs against several Ags, indicative of polyclonal activation or polyreactivity affecting the B cell lineage. B6.NZMc7 causes the production of IgM and IgG Abs against both nuclear and non-nuclear Ags and the development of severe lupus nephritis. Therefore, our results show that three defined genomic intervals from the NZM2410 SLE-prone strain each contribute specific component phenotypes that have been associated with SLE, which in combination can mediate severe disease.  相似文献   
87.
Serum levels of the vasoconstrictor endothelin-1 (ET-1) increase in ischemia and systemic hypertension. We examined the effects of ET-1 on the cochlear microvasculature. Blood vessels were cast with methacrylate in adult male Wistar Kyoto rats, 10 min after intravenous injection of ET-1 (1.0 microg/kg); control animals received saline. Systemic blood pressure was recorded continuously. ET-1 increased the average systolic pressure by 18% and average diastolic pressure by 22% (P < 0.01). Scanning electron microscopy of cast vessels showed multiple circumscribed luminal constrictions on: (1) postcapillary venules; (2) collecting veins; (3) where collecting veins merged with the spiral modiolar vein; (4) on the spiral modiolar vein itself. Circumscribed constrictions in arteries were not observed. In ET-1 injected animals focal contractions of collecting veins reduced luminal width by 13.4% +/- 2.9 (P < 0.01). In control rats, constrictions on venous casts were minimal and constrictions on arteries were not observed. The present study shows that ET-1 is involved in local control of cochlear blood flow in that it focally contracts cochlear veins. It is suggested that this might be due to the high affinity of ET-1 receptors and/or the large number of ET-1 receptors on contractile cells in venous walls.  相似文献   
88.
CI-980 (NSC 613862) is one of a novel class of 1,2-dihydropyrido[3, 4-b]pyrazines that inhibits tubulin polymerization, presumably by binding to the colchicine binding site of tubulin. In a Phase I and pharmacological study, 16 patients with advanced solid neoplasms were treated with CI-980 on a continuous 72-h infusion schedule at doses ranging from 3.0-5.4 mg/m2/day every 3 weeks. High rates of central nervous system (CNS) toxicity and neutropenia occurred in both minimally and heavily pretreated patients who were treated with CI-980 doses above 3.75 mg/m2/day, which is the maximum tolerated dose and the recommended dose for additional evaluations. CNS effects, characterized by neurocortical, mood, and cerebellar manifestations, were generally observed toward the end of the infusion and immediately posttreatment and usually resolved within 48 h after the completion of treatment. Toxicity was mild to modest at the 3.75 mg/m2/day dose level. Neither clinical nor pharmacological risk factors that may predispose patients to the development of CNS effects were evident. Although no objective antineoplastic activity was observed in this Phase I study, CI-980 steady-state plasma concentrations achieved at the recommended dose of 3.75 mg/m2/day (mean +/- SE, 5.74 +/- 0.54 nM) approached and exceeded concentrations that have been associated with significant activity in preclinical studies, indicating that additional disease-directed evaluations of CI-980 may be warranted.  相似文献   
89.
OBJECTIVE: To investigate whether fasting hyperinsulinemia is associated with a clustering of cardiovascular disease (CVD) risk factors, manifesting as the insulin resistance syndrome (IRS), in a population of native Hawaiians. RESEARCH DESIGN AND METHODS: A total of 574 native Hawaiians > or = 30 years of age were examined for blood pressure, waist-to-hip ratio (WHR), BMI, oral glucose tolerance, and fasting lipid, insulin, and C-peptide concentrations. All statistical analyses (n = 384) excluded 190 individuals who had NIDDM or who were taking hypertension medication. Using logistic regression analysis, fasting insulin and C-peptide levels were compared with CVD risk factors (glucose intolerance, hypertension, central adiposity, elevated triglyceride levels, and low HDL cholesterol levels) after adjusting for age and obesity. RESULTS: Sixty-six percent of native Hawaiians were overweight or obese, and 70% were found to have central adiposity. Fasting insulin concentrations were correlated with BMI, WHR, blood pressure, and triglyceride, HDL cholesterol, and glucose concentrations. Fasting insulin was also significantly associated with an increasing number of CVD risk factors in each participant (P < 0.001). Fasting insulin and C-peptide concentrations were independently associated with glucose intolerance, high triglyceride levels, and low HDL cholesterol levels. However, only fasting C-peptide concentrations were independently associated with hypertension and central adiposity. Apparent differences in the correlates of fasting insulin and C-peptide may be related to multiple factors and warrant further evaluation. CONCLUSIONS: This study provides cross-sectional data confirming the existence of the IRS in native Hawaiians. However, further longitudinal studies are needed to examine the relationship of insulin resistance and/or surrogate markers to increased rates of NIDDM and CVD mortality in native Hawaiians.  相似文献   
90.
Magnetic resonance imaging findings of median nerve hamartoma are presented in three patients with palpable wrist masses and median neuropathy. Fat-suppressed T1-weighted images demonstrated adipose tissue separating the neural and fibrous tissue bundles in two of three patients, which results in the distinctive appearance of these tumors on magnetic resonance imaging. Fibrous tissue appeared as enhancing longitudinal bundles within the tumor on gadolinium enhanced fat-suppressed T1-weighted images.  相似文献   
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