全文获取类型
收费全文 | 26102篇 |
免费 | 1899篇 |
国内免费 | 64篇 |
专业分类
耳鼻咽喉 | 230篇 |
儿科学 | 733篇 |
妇产科学 | 530篇 |
基础医学 | 3135篇 |
口腔科学 | 358篇 |
临床医学 | 2609篇 |
内科学 | 5131篇 |
皮肤病学 | 701篇 |
神经病学 | 2319篇 |
特种医学 | 1011篇 |
外国民族医学 | 1篇 |
外科学 | 3974篇 |
综合类 | 412篇 |
一般理论 | 60篇 |
预防医学 | 2275篇 |
眼科学 | 850篇 |
药学 | 1770篇 |
中国医学 | 18篇 |
肿瘤学 | 1948篇 |
出版年
2022年 | 171篇 |
2021年 | 348篇 |
2020年 | 227篇 |
2019年 | 344篇 |
2018年 | 426篇 |
2017年 | 365篇 |
2016年 | 397篇 |
2015年 | 447篇 |
2014年 | 698篇 |
2013年 | 1021篇 |
2012年 | 1524篇 |
2011年 | 1572篇 |
2010年 | 890篇 |
2009年 | 805篇 |
2008年 | 1519篇 |
2007年 | 1571篇 |
2006年 | 1560篇 |
2005年 | 1630篇 |
2004年 | 1589篇 |
2003年 | 1493篇 |
2002年 | 1475篇 |
2001年 | 407篇 |
2000年 | 320篇 |
1999年 | 353篇 |
1998年 | 344篇 |
1997年 | 316篇 |
1996年 | 289篇 |
1995年 | 272篇 |
1994年 | 238篇 |
1993年 | 235篇 |
1992年 | 281篇 |
1991年 | 251篇 |
1990年 | 229篇 |
1989年 | 230篇 |
1988年 | 205篇 |
1987年 | 193篇 |
1986年 | 188篇 |
1985年 | 224篇 |
1984年 | 215篇 |
1983年 | 217篇 |
1982年 | 248篇 |
1981年 | 256篇 |
1980年 | 212篇 |
1979年 | 168篇 |
1978年 | 178篇 |
1977年 | 169篇 |
1976年 | 115篇 |
1975年 | 132篇 |
1974年 | 143篇 |
1973年 | 110篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
61.
62.
Lawrence G. Raisz MD 《Clinical reviews in bone and mineral metabolism》2006,4(2):123-127
Prostaglandins, particularly PGE2, have been shown to stimulate bone formation in a number of circumstances. Endogenous prostaglandins may be important in
heterotopic ossification and fracture healing. The major source of prostaglandins in bone is the inducible form of cyclooxygenase
(COX)-2 and inhibition of COX-2 may impair bone formation. Recent studies using selective agonists for the prostaglandin EP2
and EP4 receptors, which stimulate cAMP in bone cells, have suggested that these might be used clinically to accelerate bone
formation, particularly when used locally. 相似文献
63.
Dr. Joseph A. Kuhn MD Lawrence D. Wagman MD John A. Lorant MD Fredrick W. Grannis MD Mordecai Dunst MD William R. Dougherty MD Daniel I. Jacobs MD 《Annals of surgical oncology》1994,1(4):353-359
Background: A radical forequarter amputation with partial chest wall resection (one to four ribs) has been reported for benign and malignant
lesions involving the shoulder and chest wall region. Concerns about reconstruction and postoperative pulmonary function have
previously limited more extensive chest wall resections. The current report describes the first case in which a complete unilateral
anterior and posterior chest wall resection and pneumonectomy (hemithoracectomy) accompany a forequarter amputation. A novel
reconstructive technique used the full circumference of the forearm tissue with an intact ulna as a free osseomyocutaneous
flap.
Methods: In this case, a 21-year-old patient presented with an extensive recurrent desmoid tumor that involved the shoulder, brachial
plexus, subclavian vein, and chest wall from the lateral sternal border to the midportion of the scapula and down to the eighth
rib. The operative technique involved removal of the entire right hemithorax from the midline sternum to the transverse process
posteriorly, down to the ninth rib inferiorly. Due to the absence of a rigid hemithorax, the uninvolved ipsilateral lung was
also removed. The forearm flap was prepared before final separation of the specimen and division of the subclavian vessels.
Results: Postoperatively, the patient maintained excellent oxygenation without atelectasis or fever and was extubated on the 15th
postoperative day. As expected after pneumonectomy, significant decreases from preoperative to immediate postoperative values
were noted for the vital capacity (VC) (from 4.87 L to 1.29 L), forced 1-s expiratory volume (FEV1) (from 3.77 L to 1.02 L),
and inspiratory capacity (IC) (3.33 1 to 0.99 1). Rehabilitation included a specially designed external prosthesis to provide
cosmesis and prevent scoliosis. By the 15th postoperative week the patient had returned to normal social and physical activities,
with a gradual improvement in all respiratory parameters: VC 1.52 L, FEV1 1.29 L, IC 1.04 L. There has been no evidence of
tumor recurrence at 1 year.
Conclusions: This report provides evidence that a complete hemithoracectomy, pneumonectomy, and forequarter amputation can be safely performed
for selective tumors involving the shoulder region with extensive chest wall invasion. Reconstruction may be achieved with
an extended forearm osseomyocutaneous free flap with an excellent functional outcome.
Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993. 相似文献
64.
E. Eric Muirhead David H. P. Streeten Bennie Brooks Edward T. Schroeder Lawrence W. Byers 《Blood pressure》1992,1(3):138-148
A new syndrome is described in a patient with advanced renal insufficiency. This consists of severe and persistent hypotension causing weakness but associated with a clear mental status. Also present is evidence for decreased vascular reactivity. The hypotension was not orthostatic. The hypotension was associated with a circulating vasodepressor substance having the characteristics of medullipin I. The medullipin appears to have been derived from the remaining right kidney. Hypotension existed despite the presence of major prohypertensive mechanisms, including an endstage kidney, hyperreninemia and hyperaldosteronemia. It is likely that hypotension due to hypermedullipinemia is an entity occurring in the human being. 相似文献
65.
66.
67.
L G Arlian D L Vyszenski-Moher A T Lawrence K R Schrotel H L Ritz 《The Journal of allergy and clinical immunology》1992,89(4):866-876
The outer portions (husk) of psyllium seeds are a concentrated source of natural fiber used in some bulk-fiber laxatives and cereals. They are known to elicit respiratory allergic reactions after inhalation or ingestion among sensitized individuals. Antigenic and allergenic characterization of three psyllium-seed fractions (husk, endosperm, and embryo) was conducted with crossed immunoelectrophoresis (CIE), crossed radioimmunoelectrophoresis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine the source of psyllium allergenicity. Homologous CIE demonstrated psyllium endosperm and embryo extracts contained seven and four antigens, respectively. Husk extracts were too gelatinous to react by CIE. However, heterologous CIE profiles of endosperm or embryo extracts, reacted with antihusk antibodies, resulted in antigen-antibody precipitin peaks that matched the heavy staining precipitin lines of homologous reactions for endosperm and embryo, respectively. These results indicated that commercial-grade husk, endosperm, and embryo contained similar antigens. Extracts of all three seed components contained antigens that bound IgE antibodies in the sera of 11 psyllium RAST-positive individuals, as determined by crossed radioimmunoelectrophoresis. The few prominent husk protein/peptide bands resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were common in either embryo or endosperm. Immunoblots revealed common IgE reactive bands in all three seed fractions. Microscopic examination of the powdered commercial-grade psyllium (95% pure) revealed it contained endosperm and embryo particles. These immunologic, biochemical, and microscopic findings suggest that other contaminating seed components are primarily responsible for the allergenicity of commercial-grade psyllium-husk powder rather than the husk itself. 相似文献
68.
Mary M. Klote Lawrence Y. Agodoa Kevin Abbott 《American journal of transplantation》2004,4(9):1523-1528
The incidence, risk factors, and prognosis for Mycobacterium tuberculosis (MTB) infection have not been reported in a national population of renal transplant recipients. We performed a retrospective cohort study of 15,870 Medicare patients who received renal transplants from January 1, 1998 to July 31, 2000. Cox regression analysis derived adjusted hazard ratios (AHR) for factors associated with a diagnosis of MTB infection (by Medicare Institutional Claims) and the association of MTB infection with survival. There were 66 renal transplant recipients diagnosed with tuberculosis infection after transplant (2.5 cases per 1000 person years at risk, with some falling off of cases over time). The most common diagnosis was pulmonary TB (41 cases). In Cox regression analysis, only systemic lupus erythematosus (SLE) was independently associated with TB. Mortality after TB was diagnosed was 23% at 1 year, which was significantly higher than in renal transplant recipients without TB (AHR, 4.13, 95% CI, 2.21, 7.71, p < 0.001). Although uncommon, MTB infection is associated with a substantially increased risk of mortality after renal transplantation. High-risk groups, particularly those with SLE prior to transplant, might benefit from intensified screening. 相似文献
69.
70.
Statins, inhibitors of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase, are well-established agents to lower cholesterol
levels and prevent cardiovascular morbidity. Independent of their lipid-lowering properties, statins have been shown to exert
pleiotropic immunomodulatory effects in various animal models of human autoimmune disease. In experimental autoimmune encephalomyelitis,
a murine model for multiple sclerosis, statins prevented disease onset and even reversed paralysis when treatment was initiated
after experimental autoimmune encephalomyelitis was fully established. Furthermore, well-tolerated oral statins were recently
shown to exert synergistic benefit in experimental autoimmune encephalomyelitis in combination with existing agents for multiple
sclerosis therapy. Based primarily on these encouraging results, statins are now being tested in clinical trials as a mono-therapy
for multiple sclerosis, as well as in combination with approved disease-modifying therapies. 相似文献