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101.
Adult health     
The objective of this study is to analyse the social inequalities in health status, health related behaviours and mortality among the 25-64 years Spanish population. Data come from the 1997 Spanish National Health Survey, the 1999 Spanish National Survey on Working Conditions, the 2001 Yearbook of Labour and Social Affairs Statistics and the 1998 Mortality Statistics. Most health-related behaviours are more unfavourable for men (smoking, alcohol consumption and overweight) and for less privileged social classes. Among women, entrance into the labour market is associated with more unhealthy behaviours except for overweight. Low weight, however, is more frequent among employed females. Self-perceived health status is better among men, more privileged social class persons and among workers. Whereas classical physical job hazards and work injuries mostly affect men, the impact of psychosocial job hazards and of exposures derived from the domestic work is higher for women. As in other developed countries, the paradox exists that whereas women have a poorer self-perceived health status, mortality is higher among men. The male excess in mortality is related to health-related behaviours that to a great extent are determined by traditional values assigned to masculinity, with higher consumption of tobacco (lung cancer), alcohol (cirrhosis), drugs (HIV and AIDS) and risky behaviours related to injuries. Health policies should take into account social inequalities in health determined by gender, social class and employment status. For doing so, it is important to increase the development of research on social inequalities and of health information systems sensitive to social inequalities.  相似文献   
102.
BACKGROUND: Catalonia and Spain have the highest rates of organ donation in the world. The National Transplant Organization studied the rates of potential and actual donors through the Quality Guarantee Program, but this research did not estimate potential tissue donation (PTD). The aim of this study was to define the theoretical rates of PTD at our university hospital in order to assess the main factors that exerted the greatest influence on tissue donation (TD). METHODS: We prospectively studied all deaths from May 1, of 2001 to May 31, of 2002 using a specific protocol. The selection of cornea, vessels, skin, and bone had been established by the recommendations of the Spanish Association of Tissue Banks (AEBT). We considered each deceased person as a PTD when there was no medical contraindication (MC), and obtained blood samples for serologic determinations. RESULTS: Among the 1960 deaths, 1444 (73.6%) displayed MC for TD. Only 516 (26.3%) patients were evaluated as PTD cases. Two hundred twenty-two cases (65%) were rejected due to lack of blood samples for serologic determination. The remaining 294 PTD cases were considered: family refusal of TD in 120 (40%) and consent in 174 (60%). All were corneal donors; 46 (26%) had been multitissue donors (20 vessels, 35 skin, and 30 bones) including 26 (56.5%) who were also organ donors. CONCLUSIONS: PTD cases at a university hospital represented about 25% of deaths but only 30% of PTDs actually became donors.  相似文献   
103.
BACKGROUND: Assessment of preload independent left ventricular function with conductance volumetry is traditionally accomplished by inflating a balloon in the inferior caval vein. Our aim was to investigate if a similar change in preload could be achieved by positive pressure ventilation with large tidal volume. METHODS: Conductance volumetry generating left ventricular pressure-volume loops was used in seven pentobarbital-anesthetized pigs. Changes in preload recruitable stroke work were studied, comparing the effects of inferior vena cava occlusion (IVCO) or large tidal volume (LTV). Cardiodepression was induced by halothane anesthesia and halothane + phenylephrine, and stimulation by epinephrine infusion. RESULTS: Although the decreasis in left ventricular end diastolic volume was slightly less with LTV (16.5 +/- 1.7 ml, mean +/- SEM) than with IVCO (22.4 +/- 1.7 ml) (P < 0.0001) the PRSW-slopes showed a high degree of correlation (r=0.80, P < 0.0001). Although peak tracheal pressures increased significantly to 27.8 +/- 0.9 mmHg during LTV, esophageal pressures (used as an indicator of pericardial pressure) were unchanged. CONCLUSIONS: Positive pressure ventilation with LTV is similar to IVCO in creating transient changes in preload, necessary for assessment of left ventricular systolic function. This observation was valid also during drug-induced cardiac depression and stimulation. The preload recruitable stroke work used for this validation was shown to be a reliable and stable method.  相似文献   
104.
105.
The adduct that would arise from cis opening of (+)-(1S,2R,3R, 4S)-3,4-dihydroxy-1,2-epoxy-benzo[c]phenan-threne (benzo[c]phenanthrene diol epoxide-2, where the benzylic hydroxyl group and the epoxide oxygen are trans) by the exocyclic N6-amino group of deoxyadenosine was incorporated at the marked site into four oligonucleotides, 5'-CAGA*TTTAGAGTCTGC-3', 5'-CAGTGCAGA*TTTAGAG-3', 5'-GTGCAGA*TTTAGA-3' and 5'-TGCAGA*TTTA-3'. The oligonucleotides were inserted into M13mp7L2 and the vector transfected into SOS-induced Escherichia coli SMH77 which were then plated on agar plates. The experiments reported here were designed to test the effect of the lesion position (the marked A in the sequences above) on the ligation efficiency of the insert and the frequency of failed constructs, as well as any possible effects on the mutagenic consequences of the lesion. The construct survival was estimated from the number of plaques formed following transformation, and mutation frequencies were estimated from sequencing of randomly picked plaques. Moving the adduct site to the middle of the sequence increased considerably the ligation efficiency regardless of the length of the inserted oligonucleotide, and changing the insert length or the adduct location did not markedly affect the frequency (40-58.6%) or distribution of mutations observed. Thus, so long as the local sequence (five or six bases surrounding the adduct) remains constant, the size of the oligonucleotide insert and the position of the adduct in it can be adjusted to give optimal ligation efficiency without altering the mutagenic consequences of the lesion.  相似文献   
106.
OBJECTIVES: To compare filter survival times during high-volume, continuous venovenous hemofiltration in patients with normal coagulation variables, using anti-factor Xa bioequivalent doses of nadroparin and dalteparin. To evaluate which other factors influence filter survival time. DESIGN: Randomized, prospective, double-blind, crossover study. SETTING: An 18-bed intensive care unit in a 530-bed teaching hospital. PATIENTS: Thirty-two critically ill patients with renal failure, treated with high-volume, continuous venovenous hemofiltration. INTERVENTIONS: High-volume, postdilutional continuous venovenous hemofiltration, with a standard blood flow rate of 200 mL/min and an ultrafiltrate volume of 100 L in 24 hrs, was performed with a highly permeable, large-surface cellulose triacetate membrane. Anticoagulation with anti-Xa bioequivalent doses of nadroparin and dalteparin was administered in the extracorporeal line before the filter. Blood was sampled for determination of coagulation variables before hemofiltration, 0.5, 2, 4, 6, and 12 hrs after starting the treatment, and at the end of the hemofiltration run. MEASUREMENTS AND MAIN RESULTS: Anti-Xa peak activity, time of anti-Xa peak activity, area under the curve for 0-3 hrs and filter survival time were not significantly different using nadroparin or dalteparin. When analyzing the patients according to the length of filter survival time, no relationship among anti-Xa peak activity, area under the curve for 0-3 hrs, and filter survival time was found. However, there was a strong trend toward a negative correlation between baseline platelet count and filter survival time (r2 = .11; p = .07). Mean blood urea nitrogen decreased from 81.0+/-31.9 to 41.1+/-21.2 mg/dL (p<.01) and mean creatinine decreased from 3.4+/-1.8 to 1.9+/-1.2 mg/dL (p<.01). There were no clinically important bleeding complications. CONCLUSIONS: Nadroparin and dalteparin are bioequivalent with respect to their anti-Xa activities. Using either drug, we did not find a difference in filter survival time during high-volume, continuous venovenous hemofiltration. No relationship between anti-Xa activity and filter survival time could be found. However, there is a strong trend toward a negative correlation between baseline platelet count and filter survival time. This suggests that during high-volume, continuous venovenous hemofiltration, patients with a higher baseline platelet count might need a different anticoagulation regimen to obtain longer filter survival times.  相似文献   
107.
The present analysis was performed to evaluate the impact of cytosine arabinoside (ara-C) dose escalation on hematological and cytogenetic responses in patients with chronic myelogenous leukemia (CML) who failed to respond to low-dose ara-C (LD ara-C) at a dose of 10 mg/m2/d over 10 days per month and interferon-alpha (IFNalpha, 3.5 MU/d). Following the same administration schedule, dose escalation of ara-C to 15 and 20 mg/m2/d 1-10 was performed in 36 of 119 patients (30%) due to inadequate hematological response and/or disease progression. As a result, improvement of hematological and cytogenetic responses was achieved in 22 (61%) and nine (25%) patients, respectively. Escalated ara-C dose levels were usually well tolerated, although some patients experienced deterioration of preexisting side effects. Our results support the critical role of ara-C dose towards a better disease control in CML.  相似文献   
108.
葛根素对高血压患者血浆内皮素和一氧化氮的影响   总被引:29,自引:0,他引:29  
目的:检测正常人与高血压病(EH)患者血浆内皮素、一气体氮的变化及葛根素对其的干预效应。方法:EH对照组口服苯磺酸氨氯地平5mg/d,或合和盐酸苯那普利10mg/d,每日一次,15d为一疗程。EH伍用治疗组同时合用5%GNS250ml+葛根素注射液400mg静滴,两组治疗前后检测血浆ET、NO水平变化。结果:EH各组血浆ET较正常人组均显著增高(P〈0.01),血浆NO水平及NO/ET比值除轻度E  相似文献   
109.
We microdissected 15 specimens of invasive cervical cancer co-existing with some of its precursors. Out of 15 cases, 10 carried HPV16, 2 HPV31, 1 HPV18 and 2 were HPV-negative. We found 3 HPV16 E6 variants among the 10 cases; one was A --> G in nt 131 (one case) and a second was A --> G in nt 276. The third, T;--> G in nt 350, was common, and was found in 5 of the 10 patients infected by HPV16. The type of HPV and the E6 variant were identical in all lesions within the same patient. Viral DNA present in normal epithelium was identical in type and E6 variant to HPV in the same patient's lesions. Multiple samples from invasive cancers with HPV were consistently positive. The data suggest that the originally infecting HPV, including its variant type in the E6 gene, persists unaltered in the whole series of CIN that precedes invasive cancer. Our data are compatible with an essential role of HPV manifested by persistence of the viral genome during the entire natural life history of cervical cancer. We did not confirm previous data on the specific association of invasive cancer with an HPV E6 variant (G at nt 350 rather than T). The discrepancy may depend on the relatively few cases investigated or selection of a special sub-set with progression from CIN to invasive cancer already manifest.  相似文献   
110.
BACKGROUND: Multiinstitutional experience with the management of cerebral metastases from malignant germ cell tumors (MGCT) is presented. METHODS: Clinical data regarding brain metastases from MGCT at diagnosis (Group 1 [56 patients]) or after cisplatin-based chemotherapy (Group 2 [83 patients]) were collected retrospectively. All patients in Group 1 received "conventional" cisplatin-based chemotherapy supplemented by cerebral radiotherapy (36 patients) and/or neurosurgery (10 patients). In the patients in Group 2 cerebral metastases were detected a median of 9 months after the initiation of chemotherapy. Thirty-five patients received chemotherapy, 59 patients received radiotherapy, and 25 patients underwent neurosurgery. RESULTS: The 5-year cause specific survival rate in Group 1 was 45% (95% confidence interval [CI], 31-59%). Neurosurgery and the absence of extracerebral, nonpulmonary visceral disease, but not cerebral radiotherapy, were independent predictors of good prognosis. The 5-year cause specific survival rate in Group 2 was 12% (95% CI, 4-20%), but was 39% among patients with an isolated brain recurrence (24 patients). Radiotherapy, but not chemotherapy, represented an independent predictor of good prognosis together with brain metastases at first recurrence and the absence of extracerebral recurrence. CONCLUSIONS: Among patients with brain metastases at the time of diagnosis of an MGCT, cisplatin-based chemotherapy resulted in a 5-year cause specific survival rate of 45%, with cerebral radiotherapy having limited impact. The 5-year cause specific survival rate for all patients with brain metastases after cisplatin-based chemotherapy was 12%, but increased to 39% in patients with an isolated brain recurrence. Cerebral radiotherapy (and neurosurgery) represent essential treatment modalities for patients in whom brain metastases are diagnosed after induction chemotherapy.  相似文献   
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