全文获取类型
收费全文 | 4496篇 |
免费 | 271篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 149篇 |
儿科学 | 122篇 |
妇产科学 | 168篇 |
基础医学 | 590篇 |
口腔科学 | 91篇 |
临床医学 | 352篇 |
内科学 | 939篇 |
皮肤病学 | 149篇 |
神经病学 | 456篇 |
特种医学 | 127篇 |
外科学 | 508篇 |
综合类 | 24篇 |
一般理论 | 1篇 |
预防医学 | 402篇 |
眼科学 | 88篇 |
药学 | 269篇 |
中国医学 | 20篇 |
肿瘤学 | 326篇 |
出版年
2023年 | 26篇 |
2022年 | 55篇 |
2021年 | 143篇 |
2020年 | 84篇 |
2019年 | 134篇 |
2018年 | 135篇 |
2017年 | 100篇 |
2016年 | 96篇 |
2015年 | 100篇 |
2014年 | 163篇 |
2013年 | 212篇 |
2012年 | 312篇 |
2011年 | 350篇 |
2010年 | 162篇 |
2009年 | 135篇 |
2008年 | 290篇 |
2007年 | 310篇 |
2006年 | 267篇 |
2005年 | 301篇 |
2004年 | 270篇 |
2003年 | 197篇 |
2002年 | 182篇 |
2001年 | 81篇 |
2000年 | 85篇 |
1999年 | 74篇 |
1998年 | 30篇 |
1997年 | 41篇 |
1996年 | 34篇 |
1995年 | 21篇 |
1994年 | 28篇 |
1993年 | 21篇 |
1992年 | 40篇 |
1991年 | 32篇 |
1990年 | 22篇 |
1989年 | 20篇 |
1988年 | 21篇 |
1987年 | 18篇 |
1986年 | 19篇 |
1985年 | 15篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1979年 | 8篇 |
1978年 | 8篇 |
1975年 | 7篇 |
1974年 | 10篇 |
1972年 | 12篇 |
1971年 | 16篇 |
1969年 | 14篇 |
1968年 | 7篇 |
1967年 | 7篇 |
排序方式: 共有4781条查询结果,搜索用时 15 毫秒
11.
Maria José GaldOn Estrella Durá Yolanda Andreu Maite Ferrando Rafael Poveda José Vicente Bagán 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,102(1):40-46
OBJECTIVE: This study analyzes the differences in psychological variables and symptomatology between temporomandibular disorder diagnosis subgroups. STUDY DESIGN: The sample included 114 temporomandibular disorder patients that were evaluated in coping, distress, and temporomandibular characteristics. Diagnostic muscular (n = 58) and articular (n = 56) subgroups were compared in these variables through a MANCOVA. RESULTS: Muscular patients show a higher level of general distress, specifically in the anxiety and somatization subscales and a more active coping style, with a tendency of a minor use of humor and a higher number of parafunctional habits, specifically, biting nails, hangnails, and lips. CONCLUSION: We discuss the differences found in order to design the targets of the psychological intervention of temporomandibular patients. 相似文献
12.
Giedd Jay N.; Snell John W.; Lange Nicholas; Rajapakse Jagath C.; Casey B. J.; Kozuch Patricia L.; Vaituzis A. Catherine; Vauss Yolanda C.; Hamburger Susan D.; Kaysen Debra; Rapoport Judith L. 《Cerebral cortex (New York, N.Y. : 1991)》1996,6(4):551-559
Brain magnetic resonance images (MRI) of 104 healthy childrenand adolescents, aged 418, showed significant effectsof age and gender on brain morphometry. Males had larger cerebral(9%) and cerebellar (8%) volumes (P < 0.0001 and P = 0.008.respectively), which remained significant even after correctionfor height and weight After adjusting for cerebral size, theputamen and globus pallidus remained larger in males, whilerelative caudate size was larger in females. Neither cerebralnor cerebellar volume changed significantly across this agerange. Lateral ventricular volume increased significantly inmales (trend for females), with males showing an increase inslope after age 11. In males only, caudate and putamen decreasedwith age (P = 0.007 and 0.05, respectively). The left lateralventricles and putamen were significantly greater than the rightP = 0.01 and 0.0001, respectively). In contrast, the cerebralhemispheres and caudate showed a highly consistent right greater-than-leftasymmetry (P < 0.0001 for both). All volumes demonstrateda high degree of variability. These findings highlight gender-specificmaturational changes of the developing brain and the need forlarge gender-matched samples in pediatric neuropsychiatric studies. 相似文献
13.
José I. Bilbao Manuel Ruza Jesús M. Longo Francisco Mansilla Antonio Picardi Vanessa de Villa Fernando Pardo Jesús Sola Jorge Quiroga 《Cardiovascular and interventional radiology》1994,17(4):210-213
Posttransplant lymphoproliferative disorders are infrequent tumors related to chronic immunosuppressive therapy. We present a liver transplant recipient who developed such a tumor in the porta hepatis that provoked obstruction of the entire portal triad. Treatment consisted of systemic chemotherapy, percutaneous dilatation, and placement of Wallstent endoprostheses across both biliary and portal vein stenoses. The patient died 3 weeks later of pneumonia and sepsis. At necropsy, the tumor was completely necrosed and the prostheses in both the common bile duct and the portal vein were patent. 相似文献
14.
F. A. Calvo O. Abuchaibe I. Azinovic E. Tangco J. Aristu R. Martínez F. Pardo J. Alvarez-Cienfuegos J. M. Berián 《European radiology》1992,2(1):29-34
Thirty patients with malignant tumours in the upper abdomen underwent surgery and intraoperalive radiation (IORT), using electron beam, to: the surgical bed, residual or unresected tumour. The technical aspects and results of this treatment are described. Renal, adrenal, bile duct and gastrointestinal tumours were treated. along with several other lesions. The surgical procedure consisted in 10 cases simply of exposure of the tumour for IORT and in 20 the tumour was resected. The TORT dose ranged from 10 to: 20 Gv. In 13 patients, external beam radiation was also given to: residual tumour or to: areas of high risk for recurrence. Chemotherapy was given to: 10 patients. Tolerance to: the combined treatment was acceptable; with few complications related to: IORT.The median follow-up and survival time 23 months (range 4-more than 70 months). Local tumour control rate (or tumour stabilisation) is 90%. Distant metastases developed in 19 patients (63%). The actuarial survival rate for the group projected at 70 months (maximum follow-up) is 37%. IORT in useful in the management of tumours arising in the upper abdominal organs, for palliation surgery or when resectability of the tumour is in doubt. Indications for IORT include patients with uncommon tumours of the upper abdomen who are not be candidates for standardised cancer treatment.Presented at the European Congress of Radiology, Vienna, September 15–20,1991 相似文献
15.
16.
17.
J M Pérez Trullen P J Modrego Pardo M Vázquez André J J López Lozano 《Biomedicine & Pharmacotherapy》1992,46(8):375-376
Benzodiazepines are drugs with a good tolerance that are widely used for the treatment of anxiety. Extrapyramidal side-effects are unusual. Diazepam is effective for the treatment of drug-induced dystonias, nevertheless there are some reports of Diazepam-induced dystonia. We report a case history of a patient who developed oromandibular dystonia after taking Bromazepam. The possible mechanisms that cause drug-induced dystonia are described. 相似文献
18.
Pregnancy outcome associated with natural family planning (NFP): scientific basis and experimental design for an international cohort study 总被引:1,自引:0,他引:1
J. L. Simpson R. H. Gray J. T. Queenan P. Mena A. Perez R. T. Kambic G. Tagliabue F. Pardo W. S. Stevenson M. Barbato V. H. Jennings M. J. Zinaman J. M. Spieler 《Advances in Contraception》1988,4(4):247-264
Although natural family planning (NFP) is a form of contraception without ostensible maternal risks (other than pregnancy), potential fetal risks could exist if aging gametes are involved in inadvertent fertilization. In the following report, we first review animal studies firmly establishing that aging sperm and aging oocytes (delayed fertilization) cause chromosomal abnormalities in mammals and other species. We next review human studies associating decreased coital frequency with trisomy and studies of NFP populations that generally show no increased frequency of anomalous offspring or spontaneous abortions. Our rationale for initiating an international cohort study is presented, along with the experimental design selected. Preliminary findings indicate that the experimental design chosen will indeed provide information allowing NFP safety to be assessed definitively.
Resumen Aunque la planificación familiar natural (PFN) es una forma de anticoncepción sin riesgos maternos ostensibles, (fuera del embarzo) podrían existir posibles riesgos fetales di gametos que están envejeciendo son inadvertidamente fertilizados. La primera revisión de estudios en animales establece firmemente que espermatozoides y oocytos en envejecimiento (fertilización tardía), causan anormalidades cromosómicas en mamíferos y otras especies. A continuación revisamos estudios en humanos que asocian la disminución de la frecuencia coital con trisomía, y estudios de poblaciones practicando PFN que generalmente no muestran aumento en la frecuencia de descendientes anormales o de abortos espontáneos. Presentamos nuestras razones para iniciar el estudio de una cohorte internactional ademas del diseño experimental elegido proveerá información alegando que la inocuidad de la PFN sea definitivamente valorada.
Resumé Bien que le planning familial naturel (PFN-NFP) soit une forme de contraception ne présentant pas de risques manifestes pour la mère (autres qu'une grossesse), il pourrait y avoir des risques potentiels pour le foetus si des gamètes âgés sont par inadvertance fécondés. Nous passons en revue tout d'abord des études effectuées sur des animaux, établissant fermement que le sperme veillissant et les oocytes vieillissants (fécondation retardée) provoquent des anomalies chromosomales chez les mammifères et d'autres espèces. Nous examinons ensuite des études sur des humains, qui associent diminution coitale et trisomie, et des études de populations pratiquant le PFN, qui ne révèlent généralement pas de fréquence accrue d'enfants anormaux ou d'avortements spontanés. Cette communication expose la raison pour laquelle nous avons entrepris une étude sur une cohorte internationale, ainsi que le concept d'expérimentation que nous avons choisi. Les constatations préliminaires indiquent que ce concept fournira véritablement des informations qui permettront d'évaluer de façon définitive la sécurité du PFN.相似文献
19.
J. Ignacio Herrero Juan Felipe Lucena Jorge Quiroga Bruno Sangro Fernando Pardo Fernando Rotellar Javier Alvárez-Cienfuegos Jesús Prieto 《American journal of transplantation》2003,3(11):1407-1412
Older age is not considered a contraindication for liver transplantation, but age-related morbidity may be a cause of mortality. Survival and the incidence of the main post-transplant complications were assessed in 111 adult liver transplant recipients. They were divided in two groups according to their age (patients younger than 60 years, n=54; patients older than 60 years, n=57) and both groups were compared. Older patients were more frequently transplanted for hepatitis C (p= 0.03) and hepatocellular carcinoma (p= 0.05) and their liver disease was less advanced (Child-Pugh and MELD scores were significantly lower; p=0.004 and p=0.05, respectively). After transplantation, older patients had a significantly lower survival (p=0.02). Higher age was independently associated with mortality (hazard ratio for each 10-year increase: 2.1; 95% confidence interval: 1.1- 4.0; p=0.02). The incidence of de novo neoplasia and nonskin neoplasia were higher in older patients (p=0.02 and p =0.007, respectively). Malignancy was the cause of death in one patient younger than 60 years and in 12 patients older than 60 years (p =0.002). In multivariate analysis, a higher age and smoking were independently associated with a higher risk of dying of de novo neoplasia. In conclusion, older liver transplant recipients have a significantly lower survival than younger patients. Malignancy is responsible for this decreased survival. 相似文献
20.
Stress signaling through Ca2+/calmodulin-dependent protein phosphatase calcineurin mediates salt adaptation in plants 下载免费PDF全文
Jos M. Pardo Muppala P. Reddy Shuli Yang Albino Maggio Gyung-Hye Huh Tracie Matsumoto Maria A. Coca Matilde Paino-DUrzo Hisashi Koiwa Dae-Jin Yun Abed A. Watad Ray A. Bressan Paul M. Hasegawa 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(16):9681-9686
Calcineurin (CaN) is a Ca2+- and calmodulin-dependent protein phosphatase (PP2B) that, in yeast, is an integral intermediate of a salt-stress signal transduction pathway that effects NaCl tolerance through the regulation of Na+ influx and efflux. A truncated form of the catalytic subunit and the regulatory subunit of yeast CaN were coexpressed in transgenic tobacco plants to reconstitute a constitutively activated phosphatase in vivo. Several different transgenic lines that expressed activated CaN also exhibited substantial NaCl tolerance, and this trait was linked to the genetic inheritance of the CaN transgenes. Enhanced capacity of plants expressing CaN to survive NaCl shock was similar when evaluation was conducted on seedlings in tissue culture raft vessels or plants in hydroponic culture that were transpiring actively. Root growth was less perturbed than shoot growth by NaCl in plants expressing CaN. Also, NaCl stress survival of control shoots was enhanced substantially when grafted onto roots of plants expressing CaN, further implicating a significant function of the phosphatase in the preservation of root integrity during salt shock. Together, these results indicate that in plants, like in yeast, a Ca2+- and calmodulin-dependent CaN signal pathway regulates determinants of salt tolerance required for stress adaptation. Furthermore, modulation of this pathway by expression of an activated regulatory intermediate substantially enhanced salt tolerance. 相似文献