全文获取类型
收费全文 | 378917篇 |
免费 | 24067篇 |
国内免费 | 2807篇 |
专业分类
耳鼻咽喉 | 5185篇 |
儿科学 | 8198篇 |
妇产科学 | 10076篇 |
基础医学 | 53073篇 |
口腔科学 | 11772篇 |
临床医学 | 30072篇 |
内科学 | 78232篇 |
皮肤病学 | 8544篇 |
神经病学 | 27180篇 |
特种医学 | 13912篇 |
外国民族医学 | 82篇 |
外科学 | 60545篇 |
综合类 | 9953篇 |
现状与发展 | 1篇 |
一般理论 | 64篇 |
预防医学 | 17419篇 |
眼科学 | 9437篇 |
药学 | 30965篇 |
1篇 | |
中国医学 | 2193篇 |
肿瘤学 | 28887篇 |
出版年
2021年 | 2605篇 |
2019年 | 2718篇 |
2018年 | 4512篇 |
2017年 | 3428篇 |
2016年 | 3516篇 |
2015年 | 4016篇 |
2014年 | 5688篇 |
2013年 | 7369篇 |
2012年 | 10005篇 |
2011年 | 10186篇 |
2010年 | 6179篇 |
2009年 | 5839篇 |
2008年 | 9436篇 |
2007年 | 10272篇 |
2006年 | 10193篇 |
2005年 | 9255篇 |
2004年 | 8763篇 |
2003年 | 8502篇 |
2002年 | 8177篇 |
2001年 | 28235篇 |
2000年 | 28769篇 |
1999年 | 23645篇 |
1998年 | 5158篇 |
1997年 | 4247篇 |
1996年 | 3827篇 |
1995年 | 3478篇 |
1994年 | 3103篇 |
1993年 | 2841篇 |
1992年 | 16046篇 |
1991年 | 14809篇 |
1990年 | 14153篇 |
1989年 | 13958篇 |
1988年 | 12579篇 |
1987年 | 12059篇 |
1986年 | 11101篇 |
1985年 | 10320篇 |
1984年 | 6911篇 |
1983年 | 5599篇 |
1982年 | 2718篇 |
1979年 | 5477篇 |
1978年 | 3347篇 |
1977年 | 2971篇 |
1975年 | 2641篇 |
1974年 | 3064篇 |
1973年 | 2865篇 |
1972年 | 2828篇 |
1971年 | 2773篇 |
1970年 | 2510篇 |
1969年 | 2543篇 |
1968年 | 2250篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
Platelet antibodies in systemic lupus erythematosus 总被引:2,自引:0,他引:2
C. Kaplan P. Champeix D. Blanchard J. Y. Muller J. P. Cartron 《British journal of haematology》1987,67(1):89-93
In systemic lupus erythematosus (SLE), the precise cause of the thrombocytopenia is unknown. Since platelet associated IgG is increased in many patients, it has been suggested that the destruction of platelets might be dependent on specific antibodies. In nine patients with SLE, platelet associated immunoglobulins were found together with free serum antibody which bound to platelets from all normal subjects. Using an immunoblotting technique with membrane proteins from normal platelets incubated with patient sera, target antigens were localized on a band of mol wt 108,000 in two cases (B. and N.) and on a band of mol wt 66,000 in a third (M.). When the same technique was applied to autologous platelets of patient N., autoantibody binding to the protein of mol wt 108,000 was demonstrated. The antigenic determinants were not removed from the platelets by enzyme treatment or by disulphide bond reduction, and were localized in the cytoplasmic fraction of the platelets. 相似文献
112.
113.
No impact of repeated endoscopic screens on gastric cancer mortality in a prospectively followed Chinese population at high risk. 总被引:6,自引:0,他引:6
B Riecken R Pfeiffer J L Ma M L Jin J Y Li W D Liu L Zhang Y S Chang M H Gail W C You 《Preventive medicine》2002,34(1):22-28
BACKGROUND: Gastric cancer (GC) is the leading cause of cancer deaths in China. Our study prospectively evaluated the impact of repeated endoscopic screens on GC mortality in a high-risk population in China. METHODS: Between 1989 and 1999, a population-based gastroscopic screening was conducted in 4,394 residents of Linqu County, China, a region with the highest rates of GC worldwide. Residents ages 35 to 64 years received initial gastroscopies with biopsies in 1989. Repeated endoscopies were performed in 1994 and 1999. Cancer occurrences and deaths were actively monitored throughout the entire period until July 2000. Mortality from GC was compared with expected values based on mortality rates obtained for Linqu in the 1990-1992 Chinese Cancer Mortality Survey. RESULTS: Between March 1989 and July 2000, 39,303 person-years were accumulated; 85 new GCs occurred, 29 (34.5%) were in early stage. Fifty-eight cases (68%) were identified at one of the screens. The number of observed deaths from GC (37) was close to the expected (36.8). The standardized mortality ratio was 1.01 (95% CI 0.72-1.37) for the entire cohort, 1.13 (95% CI 0.77-1.57) for males, and 0.65 (95% CI 0.26-1.32) for females. CONCLUSIONS: Despite high population coverage with repeated screens, no reduction in GC mortality was observed in this high-risk population in China. 相似文献
114.
Changes in outcome with sphincter preserving surgery for rectal cancer in Korea, 1991-2000. 总被引:3,自引:0,他引:3
S-B Lim S C Heo M R Lee S-B Kang Y J Park K J Park H S Choi S-Y Jeong J-G Park 《European journal of surgical oncology》2005,31(3):242-249
AIM: To report the clinical and oncological data of patients operated on for rectal cancers 3-5 cm from the AV over a 10 year period, including the Sphincter preservation (SP) rate. METHODS: We reviewed medical records of 304 patients with rectal cancers 3-5 cm from the AV who underwent surgical resection from January 1991 through December 2000. The 10 years were divided into three periods based on the introduction of new surgical techniques, specifically, ultralow anterior resection (ULAR) with double stapling in March 1994 and ULAR with coloanal anastomosis in April 1997. The rates of SP, complications and patient survival during these periods were compared. RESULTS: The SP rate increased significantly over the 10 years, from 16.4% in period I (January 1991-February 1994), to 53.0% in period II (March 1994-March 1997), to 86.5% in period III (April 1997-December 2000) (p<0.001). Over time, the age of the patients increased (p=0.004), the length of the distal resection margin became shorter (p=0.005), and the rate of lymph node metastasis increased (p=0.016). The factors significantly influencing SP were the period (p<0.001) and the distance from the AV (p<0.001). Over time, morbidity did not increase, and overall and disease free survival rates did not decrease. In contrast, the overall survival of N2 cases significantly increased over time (p=0.0492). CONCLUSION: Over 10 years, the SP rate in rectal cancers 3-5 cm from the AV was significantly increased by the introduction of the double stapling and coloanal anastomosis techniques. These surgical methods, however, had no effect on morbidity, disease free survival and overall survival rates. 相似文献
115.
M Yoshino Y Sakaguchi N Kuriya Y Ohtani F Yamashita T Hashimoto K Oyanagi K Tada K Narisawa T Kitagawa 《Neuropediatrics》1991,22(4):198-202
A nationwide survey of transient hyperammonemia in newborns was carried out in Japan. A total of 18 patients, consisting of 12 male and 6 female infants, were reported from 11 facilities. These neonates exhibited hyperammonemia with plasma ammonia levels in the range from 124 to 6256 micrograms/dl. Four newborn infants of the 18 died in the neonatal period, and an additional one died in the early infancy. Among the 13 infants who were alive at the time of this survey, 6 had neurological sequelae, including mental retardation, spastic quadriplegia and epilepsy. The multivariate analysis revealed that the Apgar score at 1 minute, peak plasma ammonia concentration, birth weight and sex were significant factors affecting the prognosis of life. 相似文献
116.
One of the consequences of increased intracellular calcium in response to a variety of physiological stimuli is the calcium activation of cytosolic proteases. Unlike lysosomal proteases with broad specificity, these calcium-activated neutral proteases show limited proteolysis of a restricted set of substrate proteins suggesting they may play a regulatory role in cellular physiology. In this study we show that the neural cell adhesion molecules NCAM-180 and N-cadherin are substrates for such endogenous calcium-activated neutral proteases. In contrast, a third neural cell adhesion molecule G4/L1 was not susceptible to calcium-activated proteolysis. The threshold for activation of NCAM and N-cadherin proteolysis is in the micromolar range of calcium suggesting that NCAM and N-cadherin are substrates for a mu-type calpain (calpain I). The site recognized by this protease is within intracellular domains of NCAM-180 and N-cadherin which are important for their interaction with cytoskeletal components. These results suggest that calcium-activated proteolysis at these sites in vivo could disrupt the linkage between extracellular ligand binding to these adhesion molecules and the normal intracellular effectors of such extracellular binding events. 相似文献
117.
We report an 80-year-old Japanese male with four primary malignant tumors: malignant melanoma, prostatic cancer, malignant lymphoma, and renal cell carcinoma, which occurred in that respective order. The combination of malignant melanoma and malignant lymphoma is rare. The patient was treated with BCG after an operation for malignant melanoma. He was also treated with cobalt 60 irradiation after an operation for prostatic cancer. We also discuss other reports of multiple malignant tumors and suggest some possible causes of this patient's primary malignant tumors. 相似文献
118.
119.
120.
Summary Seventy-four cases of tuberculosis of the upper limb joints (sterno-clavicular 1; shoulder 12; elbow 42; wrist 10 and fingers 9), treated by two of the authors, were reviewed. Eighty-seven percent presented at an advanced stage of destruction. The diagnosis was proved in 71 out of 74 cases. In most, the treatment was 6–12 months of chemotherapy, plaster immobilization (in order to prevent or correct deformity) and functional rehabilitation whenever possible. The sterno-clavicular and finger joints were not immobilized. Response to chemotherapy was favourable in 66 of the patients followed up. One relapse occurred at the 18th month.The affected shoulder joints healed with loss of movement, but were not painful. At the elbow, ten patients developed spontaneous bony fusion in the right-angle position, 27 had a useful range of motion and 19 had more than 70° of flexion-extension movement. One patient had an arthrodesis. At the wrist, two patients healed with painful stiffness and an arthrodesis was performed. All the finger lesions healed with painless stiffness which did not interfere much with function because rehabilitation had been started early. The authors believe that conservative management usually gives better results than arthrodesis or excision of the joint.
Résumé Les auteurs rapportent les résultats de leur expérience dans 74 cas d'ostéo-arthrite tuberculeuse du membre supérieur: 1 sterno-claviculaire, 12 scapulo-humérales, 42 coudes, 10 poignets et 9 articulations des doigts, toutes traitées personnellement par les deux auteurs principaux. Sur le plan diagnostique, 87% des patients se présentaient à un stade de destruction avancée. Le diagnostic de certitude fut obtenu dans 71 cas sur 74. Dans la majorité des cas, le traitement a été standardisé: chimiothérapie de 6 à 12 mois, immobilisation plâtrée pour prévenir ou corriger les déformations, suivie de reéducation chaque fois que possible. Les lésions de la sterno-claviculaire et des doigts ne furent pas immobilisées. Les résultats ont été bons en ce qui concerne la chimiothérapie: 66 réponses favorables chez 66 patients suivis. Il y a eu une rechute au 18éme mois. Du point de vue orthopédique, les lésions scapulo-humérales ont guéri avec une raideur de l'épaule toujours importante mais indolore. Au niveau du coude, 10 patients évoluèrent vers la fusion osseuse précoce spontanée, qui se fit à 90° de flexion grâce à l'immobilisation plâtrée; 27 guérirent avec une conservation variable des mouvements du coude dans un secteur fonctionnel et 19 d'entre eux présentaient plus de 70° d'étendue de flexion; 1 patient fut arthrodésé. Au niveau du poignet, 2 patients guérirent avec une raideur douloureuse qui nécessita une arthrodèse. Les lésions des doigts guérirent avec une raideur plus ou moins marquée, bien compensée par la mobilité des autres articulations, conservée intacte par la reéducation. Les auteurs concluent à la meilleure qualité des résultats du traitement conservateur que des classiques interventions d'arthrodèse ou de résection articulaire.相似文献