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101.
目前正在研究和发展中的半月板载荷全膝置换技术(meniscal bearing totalknee replacement)可减低全膝假体聚乙烯塑料上的接触应力,减少聚乙烯塑料的磨损。有关半月板载荷全膝置换的生物力学研究很少,本文采用X线分析方法,观察膝关节屈曲过程中半月板假体的移动和股骨髁假体在低接触应力半月板假体上的回滚运动。  相似文献   
102.
Berglin Blohm M, Hartford M, Karlsson T, Herlitz J (Division of Cardiology, Sahlgrenska University Hospital, Göteborg, Sweden). Factors associated with pre-hospital and in-hospital delay time in acute myocardial infarction: a 6-year experience. J Intern Med 1998; 243 : 243–50.

Objectives

To explore factors associated with delay time prior to hospital admission and in hospital amongst acute myocardial infarction (AMI) patients with particular emphasis on the delay time to the administration of thrombolytic therapy.

Methods

During a 6-year period we prospectively computerized pre-hospital and in-hospital time intervals for AMI patients admitted to the coronary care unit (CCU) direct from the emergency department (ED) or via paramedics, at Sahlgrenska Hospital, Göteborg, Sweden.

Results

Pre-hospital delay: independent predictors of a prolonged delay were increased age (P<> = 0.0007), female sex (P<> = 0.02) and a history of hypertension (P<> = 0.03). For AMI patients who received thrombolytic treatment and the only independent predictor of a prolonged delay was increased age (P<> = 0.005). In-hospital delay: for all AMI patients independent predictors of a prolonged delay were prolonged pre-hospital delay (P < 0.0001), increased age (P= 0.03) and a history of angina (P= 0.002), hypertension (P= 0.01) and diabetes (P= 0.01). For thrombolytic treated AMI patients independent predictors of a prolonged delay were prolonged pre-hospital delay (P < 0.0001), female sex (P= 0.02) and a history of diabetes (P= 0.02).

Conclusion

Risk factors for both pre-hospital and hospital delay time could in AMI be defined although slightly different. Two factors appeared for both, i.e. increasing age and a history of hypertension.
  相似文献   
103.
The long-term antibody responses to re-immunization in recipients of allogeneic haematopoietic stem cell transplantation (allo-HSCT) have not been well studied. We prospectively and longitudinally evaluated the antibody responses to eight vaccine antigens (diphtheria, tetanus, pertussis, measles, mumps, rubella, hepatitis B, and poliovirus) and assessed the factors associated with negative titres in 210 allo-HSCT recipients at St. Jude Children's Research Hospital. Antibody responses lasting for more than 5 years after immunization were observed in most patients for tetanus (95.7%), rubella (92.3%), poliovirus (97.9%), and, in diphtheria-tetanus-acellular pertussis (DTaP) recipients, diphtheria (100%). However, responses to pertussis (25.0%), measles (66.7%), mumps (61.5%), hepatitis B (72.9%), and diphtheria in tetanus-diphtheria (Td) recipients (48.6%) were less favourable, with either only transient antibody responses or persistently negative titres. Factors associated with vaccine failure were older age at immunization; lower CD3, CD4 or CD19 counts; higher IgM concentrations; positive recipient cytomegalovirus serology; negative titres before immunization; acute or chronic graft-versus-host disease; and radiation during preconditioning. These response patterns and clinical factors can be used to formulate re-immunization and monitoring strategies. Patients at risk for vaccine failure should have long-term follow-up; those with loss of antibody response or no seroconversion should receive booster immunizations.  相似文献   
104.
Three victims of electrical injury with necrosis of a portion of the skull had excision of overlying necrotic soft tissue soon after injury with immediate coverage of the devitalized bone with soft-tissue flaps. In two instances, the flap was from adjacent scalp; in the other a free myocutaneous flap was used. All wounds healed without sequestration of bone. Necrosis of the calvarium was substantiated by evidence of nonperfusion on a radionucleotide bone scan. In each instance, a followup bone scan showed evidence of regeneration of bone. This experience supports an earlier observation which suggested that devitalized but intact calvarium following electrical injury does not need to be removed and is the perfect in situ bone graft.  相似文献   
105.
BACKGROUND: A total of 10 455 new dermatology patients were seen in the dermatology clinics of King Fahd Hospital of the University (KFHU), Al-Khobar, Eastern Saudi Arabia, between January 1990 and December 1995. We identified 21 patients with a histopathologically confirmed diagnosis of congenital nonbullous ichthyosiform erythroderma (CNBIE). We have reviewed the epidemiological and clinical features of these patients. OBJECTIVE: To document the epidemiological and clinical features of patients with CNBIE in eastern Saudi Arabia. METHODS: We used the dermatology outpatient department (OPD) logbooks to identify diagnosed cases of CNBIE from new patients presenting with different dermatological problems over a 6-year period. We used specifically designed data-collection protocol forms to extract epidemiological and clinical data from the patients' medical records. These were entered into a computer database and analysed using standard statistical software. RESULTS: A total of 21 patients (five males, 16 females) with a male : female ratio of 0.31 : 1 were identified from a total of 10 455 new patients seen in our dermatology clinics over the study period. The occurrence rate of CNBIE in our clinics was 0.2%, or two per 1000 new dermatology cases. Nineteen (90%) of 21 CNBIE patients were born with collodion membranes. Eighty-one per cent of our patients had a positive family history of CNBIE. Consanguinity among the parents of our CNBIE patients was significantly high at 95%. CONCLUSIONS: To the best of our knowledge, this preliminary study is the first report of its kind from Saudi Arabia (documenting the clinico-epidemiological features of CNBIE patients in the Eastern Province). The high rate of parental consanguinity among the parents of our Saudi CNBIE patients may account for the high incidence rate of this genodermatosis in eastern Saudi Arabia. In comparison with results of other studies that reported a low occurrence rate of CNBIE among dermatology patients, our results were of a significantly higher rate.  相似文献   
106.
107.
The synthesis of a series of 3-acetoxyazetidin-2-ones 3a–n and 3-hydroxyazetidin-2-ones 6a–j is reported together with the antibacterial and antifungal evaluation of these compounds. An additional series of 3-acetoxyazetidin-2-ones 11a–h which possess a free carboxylic acid group on the N-1 aryl ring were obtained by treatment of suitably substituted Schiff bases 10a–h with acetoxyacetyl chloride. The novel bicyclic structures 7-acetoxy-6-phenyl-5-thia-1-azabicyclo[4.2.0]octan-8-one 13 and 7-hydroxy-6-phenyl-5-thia-1-azabicyclo[4.2.0]octan-8-one 14 were also obtained. Many of the compounds displayed antifungal activity in vitro when evaluated against the pathogenic fungi Cryptococcus neoformans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Trichosporon cutaneum, while 3-acetoxyazetidin-2-ones 11a–h containing a free carboxylic acid group on the N-1 aryl ring displayed antibacterial activity against Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa, Bacillus subtilis, Klebsiella aerogenes and Escherischia coli.  相似文献   
108.
Twenty-five hypertensives with no history of myocardial infarction and with a radiologically determined heart enlargement were examined with M-mode echocardiography and compared with a normotensive control group (n = 41). All except two of the hypertensive patients were on a beta-blocker based antihypertensive treatment regime. The relative heart volume on X-ray was significantly larger in the hypertensives, 562 ml m-2 body surface area (BSA), compared to the normotensives, 408 ml m-2 BSA (P less than 0.001). Both left ventricular diameter (LVD) in end-diastole and end-systole and left arterial (LA) diameter were significantly larger in the hypertensives (56 vs. 51 mm, P less than 0.01; 35 vs. 31 mm, P less than 0.01; 46 vs. 42 mm, P less than 0.01, respectively) as was the LV mass (296 vs. 203 g, P less than 0.001). The end-systolic wall stress (ESWS) was significantly greater in the hypertensives. Despite these findings resting left ventricular fractional shortening was the same and showed a similar correlation with ESWS (r = 0.79 and r = 0.77, respectively) in both groups. Hence, left ventricular systolic performance was not impaired in the hypertensives compared to the normotensives. These results show that an enlarged cardiac silhouette on the chest X-ray in hypertensive subjects with beta-blocker based drug therapy must be interpreted with caution and must not, a priori, be judged as a sign of an impaired systolic cardiac function.  相似文献   
109.
110.
The airborne pollen of the South American weed, Parthenium hysterophorus (American feverfew), accidentally introduced into India was found to be responsible for severe allergic rhinitis. A random clinical survey conducted on 2035 residents of Bangalore city with the aid of questionnaires and skin tests revealed that 7.1% of the study population was suffering from allergic rhinitis due to exposure to Parthenium pollen. Skin-prick tests performed on 1294 clinic patients suffering from nasobronchial allergy during the past 4 years have also shown that 42.5% were sensitive to Parthenium pollen. IgE and IgG antibodies specific for Parthenium pollen allergens were demonstrable in the sera of Parthenium-sensitive rhinitis patients. The specificity of these antibodies to Parthenium allergens was established by ELISA. A 7- to 11-fold higher stimulation was observed when lymphocytes from two Parthenium-sensitive rhinitis patients were treated in vitro with Parthenium pollen extract. To our knowledge, nowhere in the world has such a high incidence of allergic rhinitis due to a single pollen ever been reported.  相似文献   
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