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1.
Vertebral hydatidosis and paraplegia   总被引:2,自引:0,他引:2  
We report the management of two children and 11 adults with paraplegia secondary to vertebral hydatidosis. Destruction of pedicles, posterior vertebral elements and discs as well as the vertebral bodies was common and all six patients with thoracic disease had involvement of adjacent ribs. The 13 patients had a total of 42 major surgical procedures; two patients died from postoperative complications and four from complications of the disease and paraplegia. All eight patients initially treated by laminectomy or anterior decompression alone relapsed within two years and seven required further surgery. Circumferential decompression and grafting gave the best results, six of nine patients being in remission an average of three years and six months later. The prognosis for such patients is poor; remission is the aim, rather than cure. Anthelminthic drugs may improve the prognosis, but radical surgery is likely to remain the keystone of treatment in the foreseeable future.  相似文献   
2.
The application of electrolytes of low concentration to the palm causes hydration of the epidermis with swelling of the skin, closure of the sweat gland pores, and reduction of skin potential level (SPL). Solutions of high concentration are known not to produce poral closure. Previous reports of increases in SPL with increased concentration of electrolyte did not control for possible effects of hydration associated with differences in concentration. The experiments reported here compared the effects of varying concentration with and without holding hydration constant. The results indicated that the effect of concentration on both positive and negative skin potential response amplitude can be attributed to hydration, whereas the effect on SPL is not influenced by hydration. The effect of concentration on SPL was the same whether measured during rest or during periods of considerable sweat gland activity. This last finding is difficult to interpret in terms of the traditional assumption that the membrane responsible for the concentration-potential effect lies deep in the epidermis, and it was suggested that the membrane may be located in the upper sweat gland duct.  相似文献   
3.
Electrolyte Medium Effects on Measurements of Palmar Skin Potential   总被引:1,自引:0,他引:1  
Two experiments with 12 subjects each compared skin potential recordings taken simultaneously with four different electrolytes. These were polyethylene glycol, hydrated agar (at a site presoaked with water), fresh agar (i.e., not presoaked), and Unibase. The glycol controlled epidermal hydration at a minimal level, while presoaking produced a high level of hydration at the hydrated agar site. Fresh agar and Unibase represented normal recording conditions for these two electrolytes which have been recommended as “standard” for electrodermal measurements. This design permitted a comparison of two standard electrolytes with each other and with recordings from hydrated and unhydrated sites. These comparisons were made for both monophasic negative SPRs and positive SPRs and the prestimulus levels associated with each. The results replicated previous studies in showing a large effect of epidermal hydration on skin potential measurements. Recordings with agar and Unibase did not differ significantly. The effects of hydration were interpreted in terms of a reduction in the resistance of the stratum corneum and of alterations in the functioning of the dermal and epidermal membranes as a result of blockage of the sweat gland pore. In the light of this interpretation, it was suggested that both agar and Unibase substantially alter the functioning of the sweat glands under some conditions, and neither may be entirely suitable for skin potential measurements.  相似文献   
4.
Empirical evidence suggests that mortality rates for coronary artery bypass graft (CABG) surgery are lower in hospitals that perform a higher volume of the procedure. In recent years, the criteria for CABG surgery have been expanded to include patients with a wide variety of co-morbidities. To address the question of whether the volume-outcome relationship continues to exist for this new group of patients, discharge abstracts for 18,986 CABG operations at 77 hospitals in California in 1983 were analyzed using multiple-regression techniques. Higher-volume hospitals had lower in-hospital mortality (adjusted for case mix); this effect was greatest in patients who might be characterized as having "non-scheduled" CABG surgery. Higher-volume hospitals also had shorter average postoperative lengths of stay and fewer patients with extremely long stays. The results of this study suggest that the greatest improvement in average outcomes for CABG surgery would result from the closure of low-volume surgery units.  相似文献   
5.
To better understand the effects of high-altitude hypoxia on cardiac performance, healthy lowlandresiding volunteers were studied in 2 groups: 10 subjects after acute ascent to 12,500 ft (3,810 m) (acute group) and 9 subjects after chronic exposure for 6 weeks to 17,600 ft (5,365 m) and 11,000 ft (3,353 m) (chronic group). Systolic time intervals and M-mode echocardiograms were recorded at low and high altitudes. Heart rate was 21% greater at high altitude for all subjects. Preejection period/left ventricular ejection time (PEP/LVET) increased by 16% in the acute group and by 22% in the chronic group. Heart size was smaller at high altitude in both groups, with left atrial and left ventricular (LV) diameters decreasing by 10 to 12%. These changes were statistically significant (p ≤ 0.01). Despite the increase in PEP/LVET, echocardiographic measurements of LV function (percent fractional shortening and mean normalized velocity of circumferential fiber shortening) remained normal. LV isovolumic contraction time was shorter at high altitude, suggesting heightened, rather than depressed, contractility. LV function does not appear to deteriorate at high altitude. Alterations in systolic time intervals probably result from decreased preload, as reflected by smaller heart size, rather than from heart failure or depressed LV contractility.  相似文献   
6.
This investigation was designed to provide initial information on the relationship of the Shipley-WAIS Conversion scores to the WAIS-R. Subjects (N = 75) were inmates at a minimum security Federal Correctional Institution and represented various racial and ethnic groups. The results support the need for new conversion norms for Shipley to WAIS-R scores. The old Shipley to WAIS conversion scores overestimated the WAIS-R scores, particularly among lower-functioning inmates.  相似文献   
7.
The AIDMAN pilot project will connect health clinics on remote Greek islands with a mainland hospital. We have developed a virtual consultation workstation for the project, together with a satellite communication network. A UK pilot site has been used to test the concepts and applications between a surgery in Chorleywood and St Mary's Hospital in London.  相似文献   
8.
A longitudinal study (G. K. Kochanska, 1997) showed that temperamental fearfulness, assessed at toddler age via observational data and maternal ratings, moderated pathways to internalized conscience at age 4. For fearful children, maternal gentle discipline deemphasizing power predicted conscience development; for fearless children, attachment security predicted conscience development. Electrodermal reactivity assessed at age 4 on the same children was used as a physiological reflection of fearful temperament and was substituted for the earlier fearfulness measure to test the theoretical model. As expected, for electrodermally reactive children, maternal gentle discipline predicted conscience, whereas for nonreactive children, attachment security predicted conscience. The findings support the notions of (a) electrodermal reactivity at an early age as a correlate of temperament, (b) temperament as a moderator of socialization in early moral development, and (c) lovelessness in psychopathic individuals as an index of the failure of the alternative pathway (via attachment) to conscience in fearless children.  相似文献   
9.
10.
OBJECTIVE: To determine whether measurement of cotinine in saliva is a sensitive measure of exposure to second-hand smoke (SHS) among customers in bars. DESIGN: Before/after comparison of saliva cotinine and subjective assessments of SHS. SETTING: Three bars in Wellington, New Zealand, June 2003. PARTICIPANTS: Eleven non-smoking medical students spent three hours in each location. They provided saliva samples before and after the visit, counted numbers of lit cigarettes in each bar, and assessed the smokiness of the venue. Samples were tested for cotinine using liquid chromatography coupled with mass spectrometry. RESULTS: Cotinine levels post-visit were consistently higher than baseline. The mean difference was 1.03 ng/mL with a 95% confidence interval of 0.76-1.30 ng/ mL. Adjustments to post-visit levels for metabolism and clearance of cotinine made very little difference to these results. Males tended to have higher baseline levels than females, and to show smaller increases. The bar with the greatest increase in cotinine was judged to be the smokiest on the basis of averaged cigarette counts and scores for presence of smoke and odour. CONCLUSION: The cotinine in saliva, when tested with the analytic methods described here, provides a means of assessing relatively short-term exposures to SHS.  相似文献   
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