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排序方式: 共有821条查询结果,搜索用时 15 毫秒
1.
Signe S?nderkaer Marianne Schmiegelow Henrik Carstensen Lars B?geskov Nielsen J?rn Müller Kjeld Schmiegelow 《Journal of clinical oncology》2003,21(7):1347-1351
PURPOSE: To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. PATIENTS AND METHODS: The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. RESULTS: At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). CONCLUSION: In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits. 相似文献
2.
The interaction of an organic acid with sodium bicarbonate in water produces an effervescent reaction. The reaction products are carbon dioxide, water, and the sodium salt of the acid. The kinetic rate-determining step for this reaction is the dehydration of carbonic acid. The solid-solid interaction with known amounts of moisture was followed by quantitatively determining carbon dioxide evolution as a function of time. The aqueous solubilities, diffusion coefficients, dissociation constants, and solid-solid interaction rates of six different substituted benzoic acids were determined. Using a model based on diffusion of the organic acid through the aqueous layer coupled with chemical reaction, predicted rates and levels of carbon dioxide production were compared with experimental results. Included in the model were the effects of the reaction products on the solution properties of the reactants. It was found that high concentrations of substituted sodium benzoate were generated very quickly and affected the solubility of the reactants, diffusion coefficient of the acid, and the carbonic acid dehydration rate constant. Moisture content was found to have a profound influence on the interaction rate. Water provides a medium for diffusion of the reacting species as well as the reaction solvent. 相似文献
3.
Gunnar Franzn Olav G. Klausen Ronald T. Grenko John Carstensen Bo Nordenskjld 《The Laryngoscope》1991,101(6):669-673
A retrospective study was performed on 20 patients with adenoid cystic carcinomas of major salivary glands to see if DNA. patterns correlated with their prognoses. Fourteen tumors were found to be DNA. diploid; 6 were DNA aneuploid. Histologically, all DNA-aneu-ploid tumors had solid components, compared with only 5 of the DNA-diploid tumors. All of the DNA-aneuploid tumors recurred, in contrast to only 2 of the DNA-diploid tumors; the difference was highly significant (P<0.001). All of the patients with no recurrences had DNA-diploid tumors. In our study, DNA measurements of adenoid cystic carcinomas gave statistically significant information about prognosis and correlated to histological grading. We propose that evaluation of DNA content may be performed before planning the treatment of adenoid cystic carcinomas. 相似文献
4.
Jens Toft Birger Hesse Alan Rabøl Steen Carstensen Samir Ali 《European journal of nuclear medicine and molecular imaging》1997,24(4):409-414
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary. 相似文献
5.
K Alexanderson G Hensing M Leijon I Akerlind H Rydh J Carstensen P Bjurulf 《Journal of epidemiology and community health》1994,48(5):464-470
Sickness absence during pregnancy has increased in Sweden as well as in other countries. STUDY OBJECTIVE--The study aimed to describe pregnancy related sickness absence and its increase from 1985-87; to consider if the increase were parallel to an increase in sickness absence for all diagnoses or could be explained by a higher birth rate; and to compare different ways of presenting sickness absence data. DESIGN--The data from a prospective incidence study of all new sick leave spells exceeding seven days in 1985-87 were related to the population at risk through relevant data from different registers. SETTING--The county of Ostergötland, Sweden (about 400,000 inhabitants). PARTICIPANTS--Subjects were approximately 70,000 sick leave-insured women aged 16-44 years, of whom some 15,000 had sickness absences > seven days. Some 4600 women gave birth in 1985, approximately 1300 of whom were listed as having pregnancy related diagnoses. MAIN RESULTS--The number of women with sick leave associated with pregnancy related diagnoses increased by 24% (95% confidence interval (CI) 15, 33%) during the period. This diagnosis group was one of the very few with an increasing number of people listed as sick. The corresponding increase for all diagnoses in women aged 16-44 years was < 1% (95% CI 1, 3%). The increase in the number of women who gave birth was 9% (95% CI 5, 13%). The sick leave rate associated with pregnancy related disorders increased by 14% (95% CI 7, 21%) in 1985-87, while that in all women aged 16-44 years increased by 3% (95% 1, 5%). (p < 0.0001). The number of sick leave days associated with pregnancy related disorders increased by 49% (p < 0.0001) in the period--twice the equivalent increase (p < 0.0001) in the total number of sick leave days for all diagnoses taken together. The sick leave rate and duration, like the increase in these variables, varied with age. Different ways of presenting the length of absence proved complementary to each other. CONCLUSIONS--After correcting for changes in the overall sick leave rate and in the birth rate, there is still an 11% increase in the sick leave rate associated with pregnancy related disorders that needs to be explained. Medical factors cannot explain this increase but changes in attitudes and practice in relation to sickness insurance among pregnant women and their doctors merit further study. 相似文献
6.
T. Bendix A. F. Bendix E. Busch A. Jordan Tom Bendix MD 《Scandinavian journal of medicine & science in sports》1996,6(2):88-97
Conventional treatments have not slowed down the ever expanding low back pain (LBP) problem. Traditional treatment has most probably contributed to the growth of the problem. Therefore, in a search for new solutions, 'functional restoration' has been devised. In connection with chronic LBP the term has been associated with a full-day program lasting from 3 to 5 weeks. it includes multidisciplinary treatment of patients in groups with intensive physical and ergonomic training, psychological pain management, back school, as well as teaching in social/work related issues. The key concepts are 'acceptance of the pain', 'activity', 'self-responsibility', 'multidisciplinary' and 'quantitative functional evaluation (QFE)'. The latter is aimed so that the participants can feel the physical improvement, encouraging them to be able to go back to work, or at least to lead a more active life style. Several controlled studies suggest a lasting effect in terms of regaining their ability to work and improving pain behavior for a good part of disabled chronic LBP patients. However, it is noteworthy that randomized studies seemingly show poorer results than studies not employing randomized controls. 相似文献
7.
Resorbable polyesters: composition, properties, applications 总被引:3,自引:0,他引:3
Synthetic polymers, in particular polyesters based on lactic acid, glycolic acid and other raw materials are described for medical and technical applications. Their main advantages are compatibility and safety. As they are degradable in the human body they are particularly suitable for implants needed only temporarily for the healing process. Resorbable polyesters are produced by direct polycondensation or ring opening polymerization resulting in a broad range of polymers with different features. The main properties such as degradation (hydrolytic and thermal), crystallinity and mechanical strengths are discussed. These polyesters, which can be processed like other thermo-plastic polymers by extrusion and injection moulding, are used mainly for wound closure products (sutures, staples, clips), fracture fixation devices (nails, screws, plates) and parenteral depot systems for the sustained release of drugs. Possibilities for polymer and process improvement to develop better implants and additional applications are presented. 相似文献
8.
The threshold for killing of freshly hatched Drosophila larvae exposed to continuous-wave (CW) ultrasound shows a minimum at approximately 0.3 MHz. This suggests that the stiffness of the material surrounding the gas bodies in the organism is comparable to water. From this, it is apparent that the gas bodies in three-day-old larvae that we have used in earlier studies are far larger than resonance size at the frequencies (1-5 MHz) used. Yet, these larvae were killed by short exposures to low-temporal-average-intensity pulsed ultrasound with peak intensities of the order of 10 W/cm2. Hence, it appears that "large" bubbles cannot be ignored in considerations of the biological effects of pulsed ultrasound and lithotripsy. 相似文献
9.
M W Miller M Azadniv S E Pettit C C Church E L Carstensen D Hoffman 《Ultrasound in medicine & biology》1989,15(3):255-262
This study was undertaken in an attempt to determine a physical mechanism of action for a recently published report of a small but statistically significant increase in sister chromatid exchanges (SCEs) in Chinese hamster ovary cells exposed to high-intensity pulsed ultrasound. The "positive" report's protocol involved a sizeable chance of ultrasound beam impingement on the side wall of the cell exposure chamber. Ten experiments per regimen were conducted; the regimens included exposures of (a) chamber center, (b) chamber wall, (c) nine grid sites, 0.5 mm between sites, and (d) nine grid sites, 1.5 mm between sites. The last was an exact replication of the conditions previously reported to induce the small SCE effect. The results did not support the postulate of an increase in SCEs with the ultrasound exposures. 相似文献
10.
Immunomodulation by cryosurgery in malignant melanoma 总被引:1,自引:0,他引:1
U Weyer I Petersen C Ehrke A Carstensen A Nüssgen C Russ B G?ttsch L Kowalzick R Arndt E W Breitbart 《Onkologie》1989,12(6):291-296
Cryosurgery is a well-known, established method for the local destruction of tumor tissue by freezing. The assumption that, in addition to a physical and blood vascular phase, an immunological phase exists, has been discussed by many authors and tested using animal models. These results can only be transferred to humans in a limited sense. During the last year, we initiated a randomized study "Cryosurgery versus Conventional Surgery", whereby the peripheral blood and the normal skin from the areas surrounding the resection were compared. We were able to demonstrate in the peripheral blood of 8 cryosurgery patients a postoperative increase in the total and helper T-cells, HLA-DR-positive cells, and the ratio helper/suppressor T-cells in comparison to preoperative values. In the 8 patients treated with conventional surgery, these parameters decreased slightly or remained the same. The differences were highly significant (p = 0.001) to significant (p = 0.01). The results from the first 16 are patients studied presented and discussed here. 相似文献