全文获取类型
收费全文 | 2064篇 |
免费 | 260篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 57篇 |
妇产科学 | 42篇 |
基础医学 | 194篇 |
口腔科学 | 39篇 |
临床医学 | 265篇 |
内科学 | 521篇 |
皮肤病学 | 30篇 |
神经病学 | 211篇 |
特种医学 | 96篇 |
外科学 | 413篇 |
综合类 | 25篇 |
预防医学 | 148篇 |
眼科学 | 45篇 |
药学 | 125篇 |
中国医学 | 1篇 |
肿瘤学 | 147篇 |
出版年
2023年 | 15篇 |
2022年 | 18篇 |
2021年 | 35篇 |
2020年 | 33篇 |
2019年 | 18篇 |
2018年 | 39篇 |
2017年 | 54篇 |
2016年 | 61篇 |
2015年 | 99篇 |
2014年 | 165篇 |
2013年 | 188篇 |
2012年 | 96篇 |
2011年 | 80篇 |
2010年 | 130篇 |
2009年 | 129篇 |
2008年 | 71篇 |
2007年 | 58篇 |
2006年 | 64篇 |
2005年 | 49篇 |
2004年 | 44篇 |
2003年 | 56篇 |
2002年 | 45篇 |
2001年 | 47篇 |
2000年 | 26篇 |
1999年 | 45篇 |
1998年 | 42篇 |
1997年 | 51篇 |
1996年 | 39篇 |
1995年 | 35篇 |
1994年 | 23篇 |
1993年 | 15篇 |
1992年 | 16篇 |
1991年 | 25篇 |
1990年 | 18篇 |
1989年 | 21篇 |
1988年 | 23篇 |
1987年 | 20篇 |
1986年 | 23篇 |
1985年 | 34篇 |
1984年 | 14篇 |
1983年 | 24篇 |
1982年 | 17篇 |
1980年 | 13篇 |
1979年 | 15篇 |
1978年 | 22篇 |
1977年 | 14篇 |
1976年 | 15篇 |
1975年 | 15篇 |
1972年 | 14篇 |
1971年 | 15篇 |
排序方式: 共有2369条查询结果,搜索用时 15 毫秒
61.
The model of the clinical practice of emergency medicine 总被引:13,自引:0,他引:13
Hockberger RS Binder LS Graber MA Hoffman GL Perina DG Schneider SM Sklar DP Strauss RW Viravec DR Koenig WJ Augustine JJ Burdick WP Henderson WV Lawrence LL Levy DB McCall J Parnell MA Shoji KT;American College of Emergency Physicians Core Content Task Force II 《Annals of emergency medicine》2001,37(6):745-770
62.
John T. Petroff II Ankita Isor Satyanarayana M. Chintala Carolyn J. Albert Jacob D. Franke David Weinstein Sara M. Omlid Christopher K. Arnatt David A. Ford Ryan D. McCulla 《RSC advances》2020,10(44):26553
A beneficial property of photogenerated reactive oxygen species (ROS) is the capability of oxidant generation within a specific location or organelle inside a cell. Dibenzothiophene S-oxide (DBTO), which is known to undergo a photodeoxygenation reaction to generate ground state atomic oxygen [O(3P)] upon irradiation, was functionalized to afford localization within the plasma membrane of cells. The photochemistry, as it relates to oxidant generation, was studied and demonstrated that the functionalized DBTO derivatives generated O(3P). Irradiation of these lipophilic O(3P)-precursors in the presence of LDL and within RAW 264.7 cells afforded several oxidized lipid products (oxLP) in the form of aldehydes. The generation of a 2-hexadecenal (2-HDEA) was markedly increased in irradiations where O(3P) was putatively produced. The substantial generation of 2-HDEA is not known to accompany the production of other ROS. These cellular irradiation experiments demonstrate the potential of inducing oxidation with O(3P) in cells.Lipophilic O(3P)-precursors generate 2-hexadecenal upon UV-irradiation. 相似文献
63.
64.
65.
We previously showed that peripheral neuropathy of the bone marrow was associated with loss of circadian rhythmicity of stem/progenitor cell release into the circulation. Bone marrow neuropathy results in dramatic changes in hematopoiesis that lead to microvascular complications, inflammation, and reduced endothelial repair. This series of events represents early pathogenesis before development of diabetic retinopathy. In this study we characterized early alterations within the bone marrow of streptozotocin (STZ)-induced diabetic rats following treatments that prevent experimental peripheral neuropathy. We asked whether bone marrow neuropathy and the associated bone marrow pathology were reversed with treatments that prevent peripheral neuropathy. Three strategies were tested: inhibition of neutral endopeptidase, inhibition of aldose reductase plus lipoic acid supplementation, and insulin therapy with antioxidants. All strategies prevented loss of nerve conduction velocity resulting from STZ-induced diabetes and corrected the STZ-induced diabetes–associated increase of immunoreactivity of neuropeptide Y, tyrosine hydroxylase, and somatostatin. The treatments also reduced concentrations of interleukin-1β, granulocyte colony-stimulating factor, and matrix metalloproteinase 2 in STZ-induced diabetic bone marrow supernatant and decreased the expression of NADPH oxidase 2, nitric oxide synthase 2, and nuclear factor-κB1 mRNA in bone marrow progenitor cells. These therapies represent novel approaches to attenuate the diabetic phenotype within the bone marrow and may constitute an important therapeutic strategy for diabetic microvascular complications. 相似文献
66.
67.
Patients' perspectives on the management of emotional distress in primary care settings 总被引:4,自引:5,他引:4
下载免费PDF全文
![点击此处可从《Journal of general internal medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
David S. Brody MD Amir A. Khaliq PhD Troy L. Thompson II MD 《Journal of general internal medicine》1997,12(7):403-406
Objective To investigate how important treatment for emotional distress is to primary care patients in general and to primary care patients
with depression, and to evaluate the types of mental health interventions they desire.
Design Patient surveys.
Setting Five private primary care practices.
Measurements and main results Patients' desire for treatment of emotional distress and for specific types of mental health interventions were measured,
as well as patients' ratings of the impact of emotional distress, the frequency of depressive symptoms, and mental health
functioning. Of the 403 patients, 33% felt that it was “somewhat important” and 30% thought it was “extremely important” that
their physician tries to help them with their emotional distress. Patient desire for this help was significantly related to
a diagnosis of depression (P<.001), perceptions about the impact of emotional distress (p<.001), and mental health functioning (p<.001). Among patients with presumptive diagnoses of major and minor depression, 84% and 79%, respectively, felt that it was
at least somewhat important that they receive this help from their physician. Sixty-one percent of all primary care patients
surveyed and 89% of depressed patients desired counseling; 23% of all patients and 33% of depressed patients wanted a medication;
and 11% of all patients and 5% of depressed patients desired a referral to a mental health specialist.
Conclusions A majority of these primary care patients and almost all of the depressed patients felt that it was at least somewhat important
to receive help from their physician for emotional distress. The desire for this help seems to be related to the severity
of the mental health problem. Most of the patients wanted counseling, but relatively few desired a referral to a mental health
specialist.
Funded by grant R01 MH51067 from the National Institute of Mental Health. 相似文献
68.
Offodile AC Lee SW Yoo J Whelan RL Moradi D Baxter R Arnell TD Nasar A Sonoda T Milsom JW Feingold DL 《Diseases of the colon and rectum》2008,51(11):1669-1674
Purpose The study investigated the impact of prior abdominal surgery on conversions and outcomes of laparoscopic right colectomy.
Methods A consecutive series of 414 patients with cancer or adenomas who underwent a laparoscopic right colectomy from March 1996
to November 2006 were studied for surgical conversions and outcomes. Conversion was defined as an incision length > 7 cm.
Results Patients with prior abdominal surgery (n = 191) were compared with patients with no prior abdominal surgery (n = 223), and
showed no significant differences in age, ASA classification, length of stay, operative time, blood loss, harvested nodes,
tumor size, and specimen length. Significantly more wound infections occurred in the prior abdominal surgery group (22 vs.12, P = 0.023). Body mass index > 30 showed a three-fold increased risk of conversion.
Fifteen percent of the no prior abdominal surgery patients and 17 percent of the prior abdominal surgery patients were converted
(P > 0.05). Conversion was associated with a longer mean length of stay (8.8 days) relative to laparoscopically completed cases
(6.3 days) regardless of prior abdominal surgery history (P < 0.0001).
Conclusions Laparoscopic right colectomy for neoplasia was not associated with a higher conversion rate or morbidity in patients with
prior abdominal surgery. Prior abdominal surgery is not a contraindication to laparoscopic right colectomy.
Presented at the 15th International Congress of the European Association of Endoscopic Surgery, Athens, Greece, July 4 to
7, 2007. 相似文献
69.
Katherine Sellers Matthew P. Fox Michael Bousamra II Stephen P. Slone Richard M. Higashi Donald M. Miller Yali Wang Jun Yan Mariia O. Yuneva Rahul Deshpande Andrew N. Lane Teresa W.-M. Fan 《The Journal of clinical investigation》2015,125(2):687-698
Anabolic biosynthesis requires precursors supplied by the Krebs cycle, which in turn requires anaplerosis to replenish precursor intermediates. The major anaplerotic sources are pyruvate and glutamine, which require the activity of pyruvate carboxylase (PC) and glutaminase 1 (GLS1), respectively. Due to their rapid proliferation, cancer cells have increased anabolic and energy demands; however, different cancer cell types exhibit differential requirements for PC- and GLS-mediated pathways for anaplerosis and cell proliferation. Here, we infused patients with early-stage non–small-cell lung cancer (NSCLC) with uniformly 13C-labeled glucose before tissue resection and determined that the cancerous tissues in these patients had enhanced PC activity. Freshly resected paired lung tissue slices cultured in 13C6-glucose or 13C5,15N2-glutamine tracers confirmed selective activation of PC over GLS in NSCLC. Compared with noncancerous tissues, PC expression was greatly enhanced in cancerous tissues, whereas GLS1 expression showed no trend. Moreover, immunohistochemical analysis of paired lung tissues showed PC overexpression in cancer cells rather than in stromal cells of tumor tissues. PC knockdown induced multinucleation, decreased cell proliferation and colony formation in human NSCLC cells, and reduced tumor growth in a mouse xenograft model. Growth inhibition was accompanied by perturbed Krebs cycle activity, inhibition of lipid and nucleotide biosynthesis, and altered glutathione homeostasis. These findings indicate that PC-mediated anaplerosis in early-stage NSCLC is required for tumor survival and proliferation. 相似文献
70.
Kidney‐Induced Cardiac Allograft Tolerance in Miniature Swine is Dependent on MHC‐Matching of Donor Cardiac and Renal Parenchyma
下载免费PDF全文
![点击此处可从《American journal of transplantation》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M. L. Madariaga S. G. Michel G. M. La Muraglia II M. Sekijima V. Villani D. A. Leonard H. J. Powell J. M. Kurtz E. A. Farkash R. B. Colvin J. S. Allan C. L. Cetrulo Jr C. A. Huang D. H. Sachs K. Yamada J. C. Madsen 《American journal of transplantation》2015,15(6):1580-1590
Kidney allografts possess the ability to enable a short course of immunosuppression to induce tolerance of themselves and of cardiac allografts across a full‐MHC barrier in miniature swine. However, the renal element(s) responsible for kidney‐induced cardiac allograft tolerance (KICAT) are unknown. Here we investigated whether MHC disparities between parenchyma versus hematopoietic‐derived “passenger” cells of the heart and kidney allografts affected KICAT. Heart and kidney allografts were co‐transplanted into MHC‐mismatched recipients treated with high‐dose tacrolimus for 12 days. Group 1 animals (n = 3) received kidney and heart allografts fully MHC‐mismatched to each other and to the recipient. Group 2 animals (n = 3) received kidney and heart allografts MHC‐matched to each other but MHC‐mismatched to the recipient. Group 3 animals (n = 3) received chimeric kidney allografts whose parenchyma was MHC‐mismatched to the donor heart. Group 4 animals (n = 3) received chimeric kidney allografts whose passenger leukocytes were MHC‐mismatched to the donor heart. Five of six heart allografts in Groups 1 and 3 rejected <40 days. In contrast, heart allografts in Groups 2 and 4 survived >150 days without rejection (p < 0.05). These data demonstrate that KICAT requires MHC‐matching between kidney allograft parenchyma and heart allografts, suggesting that cells intrinsic to the kidney enable cardiac allograft tolerance. 相似文献