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161.
Mark A.M. Leenen Fiona Vian Fabio Cucinotta Wojciech Pisula Heiko Thiem Ralf Anselmann Luisa De Cola 《Macromolecular chemistry and physics.》2010,211(21):2286-2291
Benzo[1,2‐b:4,5‐b′]diselenophene (BDS) has been incorporated for the first time in a polymer. bis(Stannyl)‐functionalized BDS was copolymerized with 3,3′‐bis(alkyl)‐5,5′‐bithiophenes (dodecyl and tetradecyl side chains) through Stille copolymerization, to yield p‐type polymer semiconductors for organic field‐effect transistor application. The electronic and structural effect of the selenium atoms, compared to sulphur atoms in analogous copolymers, is described. The molecular weight has a decisive influence on the photophysical properties and supramolecular ordering, expressed in field‐effect transistor measurements. Saturation mobilities around 10?2 cm2 · V?1s?1 are obtained on standard silicon substrates.
162.
Two lines deriving from the same rabbit stock were selected for 8 generations for high (H) or low (L) locomotor activity score in the open field (OFS). The divergent selection was most effective up to the 3rd generation in the H line and up to the 4th generation in the L line. In further generations a decrease of OFS in the H line and a floor effect (OFS = 0) in the L line were observed. The mean OFS increased significantly in consecutive trials in the H line, whereas this increase was non-significant in the L line. There was a negative and very high correlation between the latency to enter the open field and the OFS (–0.95 and –0.98 for the H and L line, respectively). The realized heritability of the OFS was 0.46 and 0.23 in generations 0–3 within the L and H line, respectively, and 0.44 and –0.06 in generations 0–8. As calculated on the basis of divergent selection, the heritability was 0.31 and 0.15 for generations 0–3 and 0–8, respectively. The L rabbits were heavier shortly before (4th wk, P < 0.001) and after (8th wk, P < 0.01) weaning, than those of the H line, whereas the H rabbits grew faster (P < 0.05) between the 4th and 20th wk of age. There was a tendency for decreasing weight gains in consecutive generations. Generally, a lower percentage of H females delivered litters than those of the L line, but this was due to a very low percentage of such females in the 3rd and 6th generations. It can be assumed that H and L lines represent different, i.e., active and passive, coping strategies. These lines of rabbits offer increased possibilities for physiologically and ethologically oriented studies, e.g., on the welfare of caged animals. 相似文献
163.
Piotrowski A Benetkiewicz M Menzel U Díaz de Ståhl T Mantripragada K Grigelionis G Buckley PG Jankowski M Hoffman J Bała D Srutek E Laskowski R Zegarski W Dumanski JP 《Genes, chromosomes & cancer》2006,45(7):656-667
Maintenance of CpG island methylation in the genome is crucial for cellular homeostasis and this balance is disrupted in cancer. Our rationale was to compare the methylation of CpG islands in tissues (tumor, healthy breast and blood) from patients with breast cancer. We studied 72 genes in 103 samples using microarray hybridization and bisulfite sequencing. We observed tumor specific hyper- or hypomethylation of five genes; COL9A1, MT1A, MT1J, HOXA5 and FLJ45983. A general drop of methylation in COL9A1 was apparent in tumors, when compared with blood and healthy breast tissue. Furthermore, one tumor displayed a complete loss of methylation of all five genes, suggesting overall impairment of methylation. The downstream, evolutionary conserved island of HOXA5 showed hypomethylation in 18 tumors and complete methylation in others. This CpG island also displayed a semimethylated state in the majority of normal breast samples, when compared to complete methylation in blood. Distinct methylation patterns were further seen in MT1J and MT1A, belonging to the metallothionein gene family. The CpG islands of these genes are spaced by 2 kb, which shows selective methylation of two structurally and functionally related genes. The promoters of FLJ45983 and MT1A were methylated above 25% in 18 primary and metastatic tumors. Concurrently, there was also >10% methylation of healthy breast tissue in 11 and 5 samples, respectively. This suggests that the methylation process for the latter two genes takes place already in normal breast cells. Our results also point to a considerable heterogeneity of epigenetic disturbance in breast cancer. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat. 相似文献
164.
Moira J. Sheehan Wojciech P. Pawlowski 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(49):20989-20994
The ability of chromosomes to move across the nuclear space is essential for the reorganization of the nucleus that takes place in early meiotic prophase. Chromosome dynamics of prophase I have been studied in budding and fission yeasts, but little is known about this process in higher eukaryotes, where genomes and chromosomes are much larger and meiosis takes a longer time to complete. This knowledge gap has been mainly caused by difficulties in culturing isolated live meiocytes of multicellular eukaryotes. To study the nuclear dynamics during meiotic prophase in maize, we established a system to observe live meiocytes inside intact anthers. We found that maize chromosomes exhibited extremely dynamic and complex motility in zygonema and pachynema. The movement patterns differed dramatically between the two stages. Chromosome movements included rotations of the entire chromatin and movements of individual chromosome segments, which were mostly telomere-led. Chromosome motility was coincident with dynamic deformations of the nuclear envelope. Both, chromosome and nuclear envelope motility depended on actin microfilaments as well as tubulin. The complexity of the nuclear movements implies that several different mechanisms affect chromosome motility in early meiotic prophase in maize. We propose that the vigorous nuclear motility provides a mechanism for homologous loci to find each other during zygonema. 相似文献
165.
166.
Wojciech Drygas Magdalena Kwaśniewska Dorota Kaleta Joanna Ruszkowska-Majzel 《Zeitschrift fur Gesundheitswissenschaften》2008,16(1):31-36
Title Increasing recreational and leisure time physical activity in Poland–how to overcome barriers of inactivity
Aim International experts have alerted us about the burden of a sedentary lifestyle. In recent WHO reports, lack of physical activity
was placed as one of the leading risk factors of chronic diseases affecting both developed and developing countries. Despite
some beneficial changes in lifestyle during the last decade, the level of physical activity in Poland still differs from many
other European countries and international recommendations as well.
Methods The analysis was based on a review of the Medline database, the main Polish governmental documents and studies concerning
physical activity levels and the most interesting recent programmes on the topic.
Results In the article the physical activity level of the Polish population and the main factors influencing it are discussed. The
results of the national WOBASZ Project (2003–2005) revealed that nearly 35% of Polish adults are not active during their leisure
time, while only about 17% are only occasionally engaged in any exercise. Over 42% of children up to 14 years old spend above
3 h per day in front of a TV or computer monitor. Over 50% of Polish teenagers aged 15–19 years do not participate in any
kind of recreational physical activity. The most successful or promising programmes promoting active lifestyles recently applied
in Poland are described in the article. The Great Polish Nationwide Physical Activity Campaign “Revitalize Your Heart” as
an innovative and effective complex method is discussed by the authors.
Conclusions Promising results from several new innovative large-scale physical activity-promoting programmes developed and implemented
in Poland in last 5 years let us hope that the battle against a sedentary lifestyle and its health consequences could result
in further progressive improvement of the physical activity level of the whole society. 相似文献
167.
Walentyna Balwierz Szymon Skocze Jerzy Arm Ata Wojciech Strojny 《Leukemia & lymphoma》1994,13(5):515-516
Sir, Central nervous system (CNS) involvement in Hodgkin's disease (HD) seems to be more common than previously realized. 2 In the period 1988-1993, among 38 children, we have seen two cases of CNS involvement in HD, while during the period 1969-1987 we have not recognised such cases at all among 125 children. 相似文献
168.
Magdalena Cwikiel Wojciech Cwikiel Maria Albertsson 《Acta oncologica (Stockholm, Sweden)》1996,35(1):75-79
Dysphagia is the earliest and the most common symptom of malignant disease in the esophagus. The palliative effects on dysphagia of radiotherapy (RT) and chemotherapy (CT) were evaluated retrospectively and compared with the effect of the self-expanding stent, evaluated in the prospective study. After completion of treatment, 78 (56%) of 140 patients treated with RT; 31 (49%) of 63 patients treated with CT; and 53 (81%) of 66 patients treated with stent insertion were free from dysphagia. Stent treatment has a good and prompt effect on dysphagia and can be recommended for palliation of patients with malignant esophageal strictures. 相似文献
169.
Ghiselli R Giacometti A Cirioni O Mocchegiani F Orlando F Kamysz W Del Prete MS Lukasiak J Scalise G Saba V 《Journal of vascular surgery》2002,36(5):1027-1030
OBJECTIVE: The purpose of this study was to investigate the efficacy of temporin A as a prophylactic agent in a rat model of vascular graft infection from methicillin sodium-susceptible and methicillin sodium-resistant Staphylococcus epidermidis. METHODS: The prospective, randomized, controlled animal study set in a research laboratory in a university hospital used 280 adult male Wistar rats (weight range, 280 to 350 g). Graft infections were established in the back subcutaneous tissue of rats with implantation of 1-cm(2) sterile Dacron grafts followed by topical inoculation with 2 x 10(7) colony-forming units of S epidermidis. The study for each staphylococcal strain included: one control group (no graft contamination), one contaminated group that did not receive any antibiotic prophylaxis, one contaminated group that received temporin A-soaked graft, two contaminated groups that received perioperative intraperitoneal cefazolin (30 mg/kg) or vancomycin hydrochloride prophylaxis (10 mg/kg), and two contaminated groups that received temporin A-soaked graft and perioperative intraperitoneal cefazolin (30 mg/kg) or vancomycin hydrochloride (10 mg/kg) prophylaxis. All grafts were explanted at 7 days after implantation. The main outcome measure was quantification of bacterial contamination. RESULTS: Overall, the perioperative prophylaxis based on soaked grafts was not significantly different to that of parenteral vancomycin hydrochloride. Only the combination between temporin A and vancomycin hydrochloride produced a complete bacterial inhibition for both strains. CONCLUSION: Temporin A showed a similar antibacterial in vitro activity against the two different strains. The in vivo results suggest its potential use in providing prophylaxis to direct graft contamination when used in combination with parenteral vancomycin hydrochloride. 相似文献
170.
Pars plana vitrectomy and transscleral fixation of black diaphragm intraocular lens for the management of traumatic aniridia 总被引:2,自引:0,他引:2
BACKGROUND AND OBJECTIVES: Partial or complete aniridia occurring after severe ocular trauma is a difficult therapeutic problem. Diaphragm intraocular lenses were developed for the correction of aniridia, but the safety and efficacy of implanting such lenses are not well established in traumatic cases because of very few reports, and the small number of cases studied. PATIENTS AND METHODS: Six patients, 4 men and 2 women with a mean age of 44 years, were treated for traumatic aniridia using pars plana vitrectomy and transscleral fixation of a black diaphragm intraocular lens. Total aniridia was observed in 3 eyes and partial aniridia in 3 eyes. Four eyes were aphakic and severe lens subluxation was seen in 2 eyes. Vitreous hemorrhage coexisted in 2 patients and bacterial endophthalmitis was present in 1 patient. Follow-up time ranged between 4 and 39 months (mean, 23 months). RESULTS: Best-corrected visual acuity improved in 5 patients and 1 remained unchanged. Good visual acuity (20/20 - 20/40) was achieved in all cases and all lenses were well-centered. No severe complications were noted. Three of 6 patients required glaucoma topical medications pre- and postoperatively achieving good intraocular pressure control. CONCLUSION: The management of traumatic aniridia using pars plana vitrectomy and implantation of scleral fixation black diaphragm intraocular lenses seem to be safe. Very good functional results and lack of severe complications are encouraging. Additional cases with a longer follow-up study are necessary to support our opinion. 相似文献