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1.
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones.  相似文献   
2.
OBJECTIVE: To compare the ability of various methods of staging and grading to predict survival in proximal colon cancer. DESIGN: Retrospective study. SETTING: University hospital, Finland. SUBJECTS: 153 patients with primary proximal colon cancer. MAIN OUTCOME MEASURES: Staging by four classification systems, grading by two grading systems, and survival analysis based on Kaplan-Meier survival curves. RESULTS: In all staging systems the survival curves of different stages differed significantly from each other. The modified Dukes' classification was still the best predictor of survival. Grade of tumours had no significant effect on long term survival, but short term survival was affected adversely by the presence of anaplastic tissue. Tumours with no mucin had a worse prognosis than those that produced mucin. All staging methods were superior to either of the histological grading systems tested as prognosticators. Tumour depth correlated with the operator's clinical impression of radicality of operation, and also predicted survival. CONCLUSION: The clinicopathological modified Dukes' staging system was the most powerful prognosticator in proximal colonic cancer and its use in clinical practice should continue. Even a small amount of anaplastic tissue (> or = 5%) had an adverse effect on short term survival.  相似文献   
3.
Three-year results of bracing in scoliosis   总被引:2,自引:0,他引:2  
We treated 107 patients with idiopathic scoliosis with the Boston brace. The primary correction was good in all the curve patterns. The follow-up time after weaning averaged 3 years. The best final result was achieved in thoracic and lumbar curves (mean 2°). The final correction was worse in patients with an initial curve less than 30° when compared with the patients with larger curves. Except the double major curves, there was a positive correlation between the primary correction, duration of the treatment, and the final result. The results in 14 patients with bracing for 12 hours daily did not differ from the remainder. Progression of the initial curve more than 5° after the treatment was noted in 24 patients. Three patients were operated on later because of progression. We conclude that bracing can prevent progress of scoliosis.  相似文献   
4.
Guanine nucleotide-binding protein-coupled receptors have been shown to exist in both a high affinity agonist (HiAg) and a low affinity agonist (LowAg) state. The formation of the HiAg state is promoted by agonists, and the formation of this state of the receptor appears to be a critical factor in the generation of the effector-activating complex G alpha.GTP.Mg2+ and in the production of a stimulus. The magnitude of the difference in the affinity a compound has for the HiAg versus the LowAg state of the receptor has been related to the intrinsic activity of the compound. In this paper the HiAg and LowAg affinities (Ki) of full and partial dopamine agonists of varying levels of intrinsic activity were determined using membranes from Chinese hamster ovary cells stably transfected with the D2i receptor. The HiAg state was defined using the recently described dopamine agonist ligand [3H]U-86170, and the LowAg state was defined using [3H] raclopride plus 600 microM GTP. The LowAg/HiAg ratios for apomorphine (43), HW-165 (12.5), (-)-3-(3-hydroxyphenyl)-N-(1-propyl)piperidine [(-)-3-PPP] (4.5), terguride (1.6), SDZ-208-911 (1.2), and SDZ-208-912 (0.3) were found to correlate well with their electrophysiologically derived intrinsic activities (r = 0.92). Using this relationship, the intrinsic activity for compounds such as (+)-3-PPP (112%), quinpirole (104%), U-68553B (102%), and U-86170 (95%) was predicted to be high (greater than 90%); (-)-apomorphine (73%) was of high/moderate intrinsic activity, HW-165 (52%), (+)-apomorphine (51%), and (-)-3-PPP (34%) were in the intermediate range, and terguride (16.5%), SDZ-208-911 (11.7%), and SDZ-208-912 (-12%) were at the lower end of the intrinsic activity spectrum. The receptor state binding-determined intrinsic activity values for quinpirole (100%), U-86170F (94.8%), HW-165 (52.1%), (-)-3-PPP (34.3%), SDZ-208-911 (11.7%), and SDZ-208-912 (-12%) were found to correlate well (r = 0.908) with their maximum response (intrinsic activity), as determined using ATP-mediated increases in arachidonic acid release from CHO-D2i cells. In addition, the maximal effect of several of these compounds on rat striatal homovanillic acid (HVA) levels was determined. The drug-induced changes in tissue HVA levels were found to be consistent with the affinity-derived intrinsic activities of the drugs.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
5.
OBJECTIVE: To assess the impact of postoperative continuous pleural lavage (PCPL) after thoracotomy for the treatment of stage 2 pleural empyema in relation to postoperative length of stay and morbidity. METHODS: Stage 2 pleural empyema was diagnosed with computer tomography. Conservative treatment including antibiotics and pleural aspiration was introduced. 89 patients treated for stage 2 pleural empyema by thoracotomy, pleural discharge evacuation and irrigation after pleural decortication were identified after unsuccessful conservative treatment for 10 days. Whenever pleural discharge remained opaque after operation, PCPL was administered daily through the cranial chest tube and discharge evacuated through the caudal pleural suction (10-15 mmHg) tube. Risk factors related to pleural pus and patient outcome were sought for. RESULTS: Seventy-seven out of 89 patients (86.5%) had clear empyema discharge immediately after pleural decortication and irrigation. Pleural discharge remained opaque despite surgery in 12 out of 89 patients (13.5%) and PCPL was introduced. Presence of a combination of risk factors for pleural empyema, such as dental caries, alcohol abuse or previous inflammatory reaction, was predictive for persistence of opaque pleural discharge after operation (P<0.05). Need for re-thoracotomies (in 11 cases, P=ns) and postoperative deaths (P<0.05) were related with patients who did not have PCPL. The length of the hospital treatment was 20.1+/-3.1 (days+/-SEM) among patients with PCPL and 19.2+/-1.8 without PCPL before possible re-thoracotomy, respectively (P=ns). CONCLUSIONS: Early postoperative (1 day-11 months) mortality was statistically associated with patients having fibrinopurulent empyema but no PCPL. PCPL is a feasible method to clear pleural pus discharge without prolongation of hospitalization and may be recommended after thoracotomy for patients with fibrinopurulent stage 2 empyema.  相似文献   
6.
We studied the role of endogenous activated protein C (APC), the major physiological anti-coagulant with concomitant anti-inflammatory properties, on ischemia/reperfusion (I/R) in 45 patients participating in a larger trial comparing three immunosuppressive protocols in cadaveric renal transplantation: perioperative anti-thymocyte globulin (ATG, Fresenius AG, Bad Homburg, Germany), perioperative basiliximab and conventional triple therapy. Blood samples for assessing plasma APC, protein C, and lactoferrin concentrations, neutrophil CD11b and L-selectin expressions and blood leukocyte differential counts were obtained preoperatively and before reperfusion from central venous cannula, complemented with simultaneous samples from iliac artery and graft vein for calculation of transrenal differences (Delta) of study parameters at 1 and 5 min after reperfusion. Unlike basiliximab or conventional therapy groups, ATG infusion induced a substantial increase in plasma APC concentration (119 [88-144]% before infusion vs. 232 [85-1246]% after infusion, p<0.001), resulting in renal graft sequestration of APC at 1 min after reperfusion (Delta=-72 [-567 to 12]%, p<0.001). Graft APC consumption was associated with transrenal reduction of neutrophil activation markers (L-selectin r=0.7, p=0.01; lactoferrin r=-0.6, p=0.02; CD11b r=-0.8, p=0.001), and with both warm (r=0.6, p=0.01) and cold ischemia time (r=0.6, p=0.02) and donor age (r=0.6, p=0.01). These findings suggest that APC has an anti-inflammatory role in I/R injury in clinical renal transplantation.  相似文献   
7.
Abstract The treatment-mix, treatment time, and dental status of 268 male industrial workers entitled to employer-provided dental care were studied. The data were collected from treatment records of the covered workers over the 5-year period 1989-93. Treatment time was based on clinical treatment time recorded per patient visit, and the treatment procedure codes were reclassified into a treatment-mix according to American Dental Association categories, with a modification combining endodontics and restorative treatment. The mean number of check-ups followed by prescribed treatment (treatment courses) during the 5 years was 3.7 among those who had entered the in-house dental care program prior to the monitored period (old attenders). Their treatment time was stable, 57–63 min per year, while the first-year mean treatment time (170 min) of those who had entered the program during the study period (new attenders) was significantly higher (P<0.01) than the 5-year mean of the old attenders (61 min). Over the first 2 years, the treatment-mix of the new attenders showed a rise in diagnostic and preventive procedures from one-third to about one-half of all procedures, as it was for the old attenders. The new attenders' mean number of carious teeth (2.7), registered at the initial check-up visit, paralleled the mean recently demonstrated in the similar non-covered population. It was significantly higher than the 5-year mean of the old attenders (0.5) (P<0.001), but declined to the same level after the first year of treatment. It was concluded that the studied program seemed to contribute to a stabilization of treatment-mix, and to the establishment of a shorter annual treatment time within the first 2 years of treatment.  相似文献   
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10.
BACKGROUND: Alternaria alternata and Cladosporium herbarum are common fungi in outdoor environments, but their clinical significance has not been elucidated in Finland. OBJECTIVE: To evaluate the prevalence of IgE-mediated allergy and clinical outcomes caused by sensitization to fungal allergens in patients with suspected allergy. METHODS: Skin prick tests (SPTs) were performed with C. herbarum in 6,376 patients and also with A. alternata in 1,504 of these patients. SPTs were repeated in 40 patients who showed a positive reaction to either allergen using commercial and in-house extracts. The association of SPT with allergen-specific IgE antibodies in serum was evaluated. Seven patients also underwent a conjunctival challenge test with these fungal allergens. RESULTS: The prevalence of positive SPT results to A. alternata and C. herbarum was low (2.8% and 2.7%, respectively). Among the 40 patients, atopic eczema/dermatitis syndrome was found in 58%, asthma in 44%, and rhinitis in 31%. Most of the patients displayed SPT reactions also to several other fungal allergens, and 75% to 80% showed a positive SPT reaction to allergens of pet animals or pollens. Four patients had a positive reaction to A. alternata and 6 to C. herbarum in the conjunctival challenge test. CONCLUSION: In the Finnish population with allergic symptoms, IgE-mediated sensitization to 2 common fungal allergens was rare and of minor clinical importance. SPT reactions to fungi are mostly observed in patients with multiple sensitivity to various allergens.  相似文献   
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