全文获取类型
收费全文 | 176118篇 |
免费 | 982篇 |
国内免费 | 19篇 |
学科分类
医药卫生 | 177119篇 |
出版年
2022年 | 25篇 |
2021年 | 33篇 |
2020年 | 41篇 |
2019年 | 54篇 |
2018年 | 21943篇 |
2017年 | 17390篇 |
2016年 | 19524篇 |
2015年 | 930篇 |
2014年 | 815篇 |
2013年 | 789篇 |
2012年 | 6998篇 |
2011年 | 21015篇 |
2010年 | 18813篇 |
2009年 | 11529篇 |
2008年 | 19537篇 |
2007年 | 21766篇 |
2006年 | 606篇 |
2005年 | 2233篇 |
2004年 | 3434篇 |
2003年 | 4388篇 |
2002年 | 2504篇 |
2001年 | 296篇 |
2000年 | 438篇 |
1999年 | 180篇 |
1998年 | 192篇 |
1997年 | 198篇 |
1996年 | 85篇 |
1995年 | 97篇 |
1994年 | 96篇 |
1993年 | 56篇 |
1992年 | 46篇 |
1991年 | 99篇 |
1990年 | 132篇 |
1989年 | 80篇 |
1988年 | 56篇 |
1987年 | 39篇 |
1986年 | 30篇 |
1985年 | 42篇 |
1984年 | 26篇 |
1983年 | 22篇 |
1982年 | 26篇 |
1980年 | 42篇 |
1974年 | 21篇 |
1970年 | 23篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1935年 | 22篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Yasushi Rino Munetaka Masuda Norio Yukawa Hitoshi Murakami Ken Takata Tsutomu Hayashi Shin-ichi Suzuki Kei-ichiro Kasama Toshio Imada 《Esophagus》2010,7(1):71-74
In this report, we describe our traction suture technique of the pericardium for suspension of the heart without hemodynamic
instability to obtain excellent exposure in the abdominal-transhiatal approach (TH). Our technique is an application of deep
pericardium stitches for off-pump coronary artery bypass surgery. In detail, the left hepatic lobe is detached at its triangular
ligament from the diaphragm and is deflected to the right. Then, the tendinous portion of the diaphragm arching over the esophagus
is incised upward in the midline until the pericardium is exposed. Pericardial fatty tissue was dissected. Three U-shaped
sutures reinforced with a felt pledget are placed on the posterior aspect of the pericardium and diaphragm. A 15 Fr. flexible
catheter is placed over both ends of the suture to avoid damage of the adjacent organs. Finally, the sutures are fixed to
the drape of anterior wall of the patient to maintain good exposure. 相似文献
992.
Benjamin L. Predmore David J. Lefer 《Journal of cardiovascular translational research》2010,3(5):487-498
The physiological role of the gaseous signaling molecule hydrogen sulfide (H2S) was first realized in the mid-1990s with the work of Abe and Kimura. Since then, it has become evident that this endogenous
gas is extremely important in the homeostasis of the cardiovascular system and the pathogenesis of cardiovascular disease.
Several biotechnology companies have developed and are developing H2S-based therapeutic compounds, and there are ongoing clinical trials investigating the therapeutic potential of H2S. Several organic and chemical compounds that are known H2S donors have the potential to be developed into effective H2S-based therapeutic agents. This review will provide a historical and current perspective on the role(s) of H2S in the cardiovascular system and the current state of development and future outlook of H2S-based therapies for cardiovascular disease. 相似文献
993.
Shelly Choo Guy Marti Manuel Nastai Jessie Mallalieu Michele A. Shermak 《Obesity surgery》2010,20(10):1422-1428
Background
The aim of this study is to assess skin strength in MWL patients relative to control cosmetic abdominoplasty patients biophysically, biochemically, and histologically. Growing success of weight loss programs has brought about an increase in the MWL population. Skin quality is thought to be impaired by MWL, but there are no compelling studies that have fully addressed the structural mechanisms involved. 相似文献994.
Shingo Shibata Chiori Ueno Tsuyoshi Ito Keitaro Yamanouchi Takashi Matsuwaki Masugi Nishihara 《Age (Dordrecht, Netherlands)》2010,32(2):239-253
Growth hormone (GH) is known to have a pivotal role in the maintenance of skeletal muscle mass. Sarcopenia, the loss of skeletal
muscle mass, is a common phenomenon in aging, and it is widely accepted that sarcopenia is largely attributed to age-related
decline in GH secretion. In the present study, we tested if human growth hormone transgenic rats (GH-TG rats) whose plasma
GH levels are maintained relatively low could be an appropriate model for sarcopenia. Analyses of GH-TG rats revealed that
they exhibit skeletal muscle growth defect as well as atrophy of myofibers. The number of myofibers in tibialis anterior muscle
was comparable to that of WT rats, while the proportion of type I slow myofibers in tibialis anterior muscle was increased
in GH-TG rats after 5 months. Neither increased expression of ubiquitin ligases, MuRF1 and MAFbx, nor indication of apoptotic
cell death was observed. Notably, myogenic differentiation potential of skeletal muscle progenitor cells in GH-TG rats was
lower than WT rats, and this was accompanied by increased adipogenic potential. These results indicate that GH-TG rats could
be a useful model to elucidate the mechanism of sarcopenia induced by reduced GH action and raised the possibility that decreased
GH action may cause an alteration of differentiation potential of skeletal muscle progenitor cells. 相似文献
995.
996.
Rafael E. de la Hoz Michael R. Shohet Jeffrey M. Cohen 《Current allergy and asthma reports》2010,10(2):77-83
The World Trade Center disaster and its recovery work involved a range of hazardous occupational exposures that have not been
fully characterized but that can be reasonably assumed to have the potential to cause mucosal inflammation, preferentially
(but not exclusively) in the upper airway. A high prevalence of rhinosinusitis and upper airway disease (UAD) symptoms was
reported by several early surveys. Clinical studies demonstrated objective, clinically significant, and persistent chronic
perennial rhinosinusitis and UAD—with or without seasonal exacerbation—in a large proportion of patients. Demonstration of
an association between UAD and available exposure indicators has been limited. Atopy seemed to be associated with increased
UAD symptom severity and to be a risk factor for upper, but not lower, airway disease. World Trade Center-related UAD is considered
an irritant-induced disease but not, in many cases, of acute onset. No data thus far suggest an increased upper airway cancer
incidence. 相似文献
997.
Hypertension is an important risk factor for the development of heart failure. Increased production of reactive oxygen species
(ROS) contributes to cardiac dysfunction by activating numerous pro-hypertrophic signaling cascades and damaging the mitochondria,
thus setting off a vicious cycle of ROS generation. The way in which oxidative stress leads to exacerbation of systolic and
diastolic dysfunction is still unclear, however. In skeletal muscle and ischemic myocardium, increased ROS production causes
preferential oxidation of myofibrillar proteins and provides a mechanistic link between oxidative damage and impaired contractility
through disruption of actin-myosin interactions, enzymatic functions, calcium sensitivity, and efficiency of cross-bridge
cycling. In this review, we summarize recent findings in the fields of heart failure and sarcomere biology and speculate that
oxidative damage to myofibrils may contribute to the development of heart failure. 相似文献
998.
Catherine A. Brownstein Paul Wicks 《Clinical orthopaedics and related research》2010,468(10):2581-2585
Background
Osteogenesis imperfecta (OI) is an inherited connective tissue disorder with many phenotypic presentations ranging from mild to severe. It is often called “brittle bone disease.” Treatment consists of physical therapy, surgical interventions, medications and, in some cases, experimental therapies. Because treatment is not standardized and is often experimental, information on the success of different methods is usually not available or well documented. 相似文献999.
1000.
Mitnala Sasikala D. Nageshwar Reddy Nitesh Pratap Sanjeev Kumar Sharma P. Reddy Balkumar Anuradha Sekaran Rupa Banerjee D. Bhaskara Reddy 《Indian journal of gastroenterology》2009,28(5):169-174