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11.
This paper examines why the law concerns itself with euthanasia. The nature of the right to life and its protection in law is explored. Such a right demands legal intervention to prohibit, or at least control, involuntary and non-voluntary euthanasia. Voluntary euthanasia is not a violation of the individual's right to life as such, so on what grounds can law limit autonomy by prohibiting such conduct? It is suggested that, while concepts of sanctity of life still play a part in the legal debate, fears of abuse in any scheme for voluntary euthanasia largely explain the reluctance of many jurisdictions to follow the example of The Netherlands. Finally, the paper asks whether reform and regulation of voluntary euthanasia are as attractive options as they are sometimes portrayed.  相似文献   
12.
We studied the concentration of hyaluronan in cerebrospinal fluid (CSF) in various diseases and attempted to define its reference interval. A radioassay utilizing cartilage proteins with affinity for hyaluronan was used in determining the concentration of 200 lumbar and 27 ventricular CSF specimens and 11 brain cyst fluids. Molecular weight distributions were determined by gel chromatography and localization in brain tissue by histochemistry. The hyaluronan level of lumbar CSF showed an increase with age; comparatively healthy children had (mean +/- SD) 50 +/- 41 micrograms/L (n = 40) and adults 166 +/- 77 micrograms/L (n = 9); i.e. significantly different values. The highest level was recorded in a patient with meningitis (> 8000 micrograms/L). More than 4000 micrograms/ L was noted in a patient with tumour metastasis in the cerebellum. Significantly elevated levels were especially found with spinal stenosis, head injury and cerebral infarction, but also in inflammatory medical disorders, hydrocephalus and encephalitis. We found no significant increase in multiple sclerosis and some other neurological diseases. Ventricular CSF of adults contained significantly less hyaluronan (53 +/- 73 micrograms/L; n = 16) than lumbar CSF. Hyaluronan in cyst fluids varied from 31 to 25,000 micrograms/L. Weight average molecular weight of hyaluronan in CSF was 2.9-3.0 x 10(5) and in brain tumour cyst fluid 2.4 x 10(6). In search for the origin of hyaluronan in CSF it was found that its concentration in the choroid plexus and leptomeninges was low, but that hyaluronan was accumulated in the superficial layer of the cerebral cortex. Continued screening for hyaluronan in CSF may be valuable in cases of inflammatory diseases, tumours and obstruction to CSF flow.  相似文献   
13.
Clinical and ergometric data were derived from 1098 consecutive exercise tests in patients with a first acute myocardial infarction between 1974-1983. In 1992 a follow-up was performed in order to analyse the importance of a submaximal early exercise test, in combination with clinical data, for the prediction of short- and long-term prognosis of cardiovascular death. The relative value of 20 clinical variables, including medical history, markers of infarction size, medication etc., and 28 variables at exercise test were studied. Univariate, multivariate and survival analysis, for estimation of prognosis and independent prediction of cardiovascular death was used. Independent clinical risk factors for cardiovascular death were (1) Within 1 year: relative heart volume (ml.m-2 body surface area) on chest X-ray. (2) Long-term mortality: maximum heart rate and relative heart volume, diabetes, age and digitalis medication. Independent exercise risk factors were: (1) Within 1 year: heart rate, ventricular arrhythmia and ST depression > or = 1 mm before exercise, diastolic blood pressure at maximum exercise and target heart rate. (2) Long-term mortality: angina pectoris and/or ST depression > or = 1 mm at maximum exercise. In subgroups of patients with clinical risk factors, mortality risk increased if there were signs of angina pectoris and/or ST depression > or = 1 mm during exercise. The risk increased 100% in diabetics, 91% with age > 70 years, 58% with relative heart volume > or = 500 ml.m-2 body surface area, 42% with heart rate > or = 100 at admission, and 34% with digitalis medication. No increase was found in the subgroup of patients without clinical risk factors. Thus, submaximal early exercise stress testing provides important information for short- and long-term prognosis in patients after the first acute myocardial infarction compared to clinical evaluation alone.  相似文献   
14.
When cleft lip and palate treatment was introduced at Gothenburg in 1957, the procedure used was early bone grafting (EBG). By 1965, EBG had been omitted from the regimen, bone grafting being postponed until the appearance of mixed dentition. Analysis of the results of both techniques showed maxillary retrusion of different degrees. Accordingly, this routine was abandoned in 1975, being replaced by a procedure which is characterised by delayed closure of the hard palate (DCHP). Thus, the surgical procedure comprised the following steps: 1, lip closure at 1-2 months of age; 2, soft palate repair at 6-8 months; 3, final lip-nose surgery at 12 months; and 4, closure of the left in the hard palate, and bone grafting to the alveolar process during mixed dentition at about 8-10 years of age. Follow-up has shown the majority of patients to manifest acceptable speech development during childhood, though problems may occur in some cases. Maxillary growth has been found to be improved after DCHP, and at present the need of maxillary advancement surgery has been reduced to approximately 5% of cases, as compared with the former rates of 50% of cases among those treated with EBG, and of 25% among those treated with the vomer flap procedure.  相似文献   
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BACKGROUND: Advanced chronic liver disease is characterized by peripheral arterial vasodilation and increased plasma catecholamine concentrations. These haemodynamic alterations may reflect impaired vascular responsiveness due to autonomic nerve dysfunction. METHODS: Three established non-invasive tests based on the heart reactions to deep breathing (expiratory/inspiratory (E/I) ratio) and to tilt (acceleration and brake indices) were used to evaluate age-related autonomic nerve function in 27 patients with chronic alcoholic and non-alcoholic liver disease. Liver function was estimated by demethylating capacity. The results were compared with a control group consisting of 56 healthy individuals. RESULTS: Overall, 12 patients (52%) had autonomic neuropathy (10 of 13 (77%) patients with alcoholic and 2 of 14 (14%) with non-alcoholic liver disease). Variance analysis showed that the age-corrected E/I ratio, but not the acceleration and brake indices, was significantly decreased compared with controls both in patients with alcoholic and non-alcoholic liver disease, indicating vagal nerve dysfunction (P < 0.0001 and 0.0133, respectively). The decrease in E/I ratio was also significantly more pronounced (-1.77 (0.62) (median (interquartile range)) versus 0.76 (0.70); P = 0.049) in patients with alcoholic compared with non-alcoholic liver disease. Furthermore, in contrast to non-alcoholics, patients with alcoholic liver disease were unable to increase their diastolic blood pressure after return to upright from a tilted position, indicating additional sympathetic neuropathy. CONCLUSIONS: Autonomic, mainly vagal, nerve dysfunction is common in patients with liver diseases and is further exaggerated by alcohol abuse. Autonomic neuropathy may contribute to altered vascular responsiveness in patients with chronic liver diseases.  相似文献   
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18.
Several parallel programming languages, libraries and environments have been developed to ease the task of writing programs for multiprocessors. Proponents of each approach often point out various language features that are designed to provide the programmer with a simple programming interface. However, virtually no data exist that quantitatively evaluate the relative ease of use of different parallel programming languages. The paper borrows techniques from the software engineering field to quantify the complexity of three predominant programming models: shared-memory, message-passing and high-performance Fortran. It is concluded that traditional software complexity metrics are effective indicators of the relative complexity of parallel programming languages. The impact of complexity on run-time performance is also discussed in the context of message-passing vs. HPF on an IBM SP2. © 1998 John Wiley & Sons, Ltd.  相似文献   
19.
Canisters with a cast iron insert for mechanical strength and a 50-mm thick copper shell as corrosion protection are planned to be used for disposal of spent nuclear fuel in Sweden and Finland. Chloride can be considered “beneficial”, as it promotes active dissolution of copper rather than passivation (which might result in pitting), but a high concentration of chloride in solution would increase the driving force for corrosion through the formation of soluble copper chloro complexes. Thermodynamic calculations are performed in this study with the PHREEQC software and three of its accompanying databases, and a comparison with experimental data is performed to select the database to be used when evaluating repository performance. The activity coefficient models are given special attention. For the assessment of chloride-assisted corrosion of a KBS-3 canister, chloride concentrations pessimistically up to 5 mol/kg are used (in Finland and Sweden, the groundwater and bentonite porewater chloride concentrations are not expected to exceed 1 mol/kg). The resulting copper solubilities are then considered in different mass transport cases.  相似文献   
20.
A course on computer systems performance analysis has been adapted for several different distance education delivery options, including an interactive television system, face-to-face presentation at a satellite campus, and delivery over the Internet to independent study students. Of the 122 students who have enrolled in this graduate-level course for a grade over the three-year period analyzed, half have been nontraditional students who never set foot on campus. These remote students have a substantially higher drop-out rate than the traditional on-campus students, and frequently indicate a strong preference for face-to-face instruction in a traditional classroom setting. Nevertheless, due to significant differences in the characteristics of the two student groups, the remote students typically earn higher final course grades than the on-campus students. While there is a strong demand for delivery of this type of advanced course to remote students, more still needs to be done to effectively engage these students in the learning process  相似文献   
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