全文获取类型
收费全文 | 476805篇 |
免费 | 41773篇 |
国内免费 | 30347篇 |
专业分类
耳鼻咽喉 | 3970篇 |
儿科学 | 5894篇 |
妇产科学 | 8458篇 |
基础医学 | 60678篇 |
口腔科学 | 7941篇 |
临床医学 | 62363篇 |
内科学 | 71300篇 |
皮肤病学 | 4701篇 |
神经病学 | 25001篇 |
特种医学 | 17575篇 |
外国民族医学 | 260篇 |
外科学 | 46468篇 |
综合类 | 74576篇 |
现状与发展 | 89篇 |
一般理论 | 40篇 |
预防医学 | 34597篇 |
眼科学 | 12960篇 |
药学 | 48587篇 |
433篇 | |
中国医学 | 25068篇 |
肿瘤学 | 37966篇 |
出版年
2024年 | 1489篇 |
2023年 | 6818篇 |
2022年 | 17406篇 |
2021年 | 22076篇 |
2020年 | 16247篇 |
2019年 | 14499篇 |
2018年 | 15539篇 |
2017年 | 13795篇 |
2016年 | 13104篇 |
2015年 | 19606篇 |
2014年 | 24310篇 |
2013年 | 22259篇 |
2012年 | 32661篇 |
2011年 | 37557篇 |
2010年 | 23985篇 |
2009年 | 18780篇 |
2008年 | 25053篇 |
2007年 | 25138篇 |
2006年 | 24470篇 |
2005年 | 23775篇 |
2004年 | 18278篇 |
2003年 | 17019篇 |
2002年 | 14350篇 |
2001年 | 12195篇 |
2000年 | 11834篇 |
1999年 | 12386篇 |
1998年 | 7751篇 |
1997年 | 7726篇 |
1996年 | 5938篇 |
1995年 | 5418篇 |
1994年 | 4711篇 |
1993年 | 3502篇 |
1992年 | 4359篇 |
1991年 | 3780篇 |
1990年 | 3286篇 |
1989年 | 2933篇 |
1988年 | 2465篇 |
1987年 | 2116篇 |
1986年 | 1843篇 |
1985年 | 1468篇 |
1984年 | 974篇 |
1983年 | 744篇 |
1982年 | 574篇 |
1981年 | 522篇 |
1980年 | 439篇 |
1979年 | 470篇 |
1978年 | 313篇 |
1977年 | 346篇 |
1976年 | 296篇 |
1974年 | 291篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges. 相似文献
13.
Harvey A. Siegal PhD ; Paul J. Draus PhD ; Robert G. Carlson PhD ; Russel S. Falck MA ; Jichuan Wang PhD 《The Journal of rural health》2006,22(2):169-173
CONTEXT: Although the nonmedical use of stimulant drugs such as cocaine and methamphetamine is increasingly common in many rural areas of the United States, little is known about the health beliefs of people who use these drugs. PURPOSE: This research describes illicit stimulant drug users' views on health and health-related concepts that may affect their utilization of health care services. METHODS: A respondent-driven sampling plan was used to recruit 249 not-in-treatment, nonmedical stimulant drug users who were residing in 3 rural counties in west central Ohio. A structured questionnaire administered by trained interviewers was used to collect information on a range of topics, including current drug use, self-reported health status, perceived need for substance abuse treatment, and beliefs about health and health services. FINDINGS: Participants reported using a wide variety of drugs nonmedically, some by injection. Alcohol and marijuana were the most commonly used drugs in the 30 days prior to the interview. Powder cocaine was used by 72.3% of the sample, crack by 68.3%, and methamphetamine by 29.7%. Fair or poor health status was reported by 41.3% of the participants. Only 20.9% of the sample felt they needed drug abuse treatment. Less than one third of the sample reported that they would feel comfortable talking to a physician about their drug use, and 65.1% said they preferred taking care of their problems without getting professional help. CONCLUSIONS: Stimulant drug users in rural Ohio are involved with a range of substances and hold health beliefs that may impede health services utilization. 相似文献
14.
We report clinical, neuroradiologic features, and neuropathologic findings of a 76‐year‐old man with coexistent Pick’s disease and progressive supranuclear palsy. The patient presented with loss of recent memory, abnormal behavior and change in personality at the age of 60. The symptoms were progressive. Three years later, repetitive or compulsive behavior became prominent. About 9 years after onset, he had difficulty moving and became bed‐ridden because of a fracture of his left leg. His condition gradually deteriorated and he developed mutism and became vegetative. The patient died from pneumonia 16 years after the onset of symptoms. Serial MRI scans showed progressive cortex atrophy, especially in the bilateral frontal and temporal lobes. Macroscopic inspection showed severe atrophy of the whole brain, including cerebrum, brainstem and cerebellum. Microscopic observations showed extensive superficial spongiosis and severe neuronal loss with gliosis in the second and third cortical layers in the frontal, temporal and parietal cortex. There were Pick cells and argyrophilic Pick bodies, which were tau‐ and ubiquitin‐positive in neurons of layers II–III of the above‐mentioned cortex. Numerous argyrophilic Pick bodies were observed in the hippocampus, especially in the dentate fascia. In addition, moderate to severe loss of neurons was found with gliosis and a lot of Gallyas/tau‐positive globus neurofibrillary tangles in the caudate nucleus, globus pallidus, thalamus, substantia nigra, locus coeruleus and dentate nucleus. Numerous thorned‐astrocytes and coiled bodies but no‐tuft shaped astrocytes were noted in the basal ganglion, brainstem and cerebellar white matter. In conclusion, these histopathological features were compatible with classical Pick’s disease and coexistence with progressive supranuclear palsy without tuft‐shaped astrocytes. 相似文献
15.
Shao-Liang Chen Tim-Mo Chen Hsian-Jenn Wang 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(8):846-855
Finding appropriate soft-tissue to cover a wound located over the middle or distal portion of the foot can be challenging. A distally based sural fasciomusculocutaneous flap including the sural nerve and a midline cuff of the gastrocnemius muscle can be used for this purpose. This flap is designed on the proximal third of the posterior calf and is nourished in a retrograde manner by the lower peroneal septocutaneous perforators, through the vascular axis of the sural nerve to the musculocutaneous perforators of the gastrocnemius muscle. Between October of 2002 and January of 2004, this flap was applied in nine individuals, including four diabetic patients. The skin defects all resulted from trauma, osteomyelitis or chronic ulcer, and combined with bone or tendon exposure. One flap developed distal necrosis. The other flaps survived fully and provided good contour. In our series, diabetes mellitus seemed not to compromise the vascularity of the flap. The distally based sural fasciomusculocutaneous flap is very useful for lower limb reconstruction, particularly for the foot, because of its long vascular pedicle and the availability of the skin portion of the proximal calf based on direct branches between the musculocutaneous perforators and the neurovascular axis of the sural nerve. This is an important variant of the sural neurocutaneous flap and it appears to be a good alternative to free flaps for resurfacing the foot. 相似文献
16.
A new semi-empirical formula for the evaluation of (n,(3)He) reaction cross-sections at the energy of 14.6 and 20 MeV is presented. Formula was derived using the analytical expression for the evaluation of the (3)He spectrum within the frame of pre-equilibrium exciton model. The systematics obtained is compared with the empirical formula for the (n,(3)He) reaction cross-section. 相似文献
17.
置身RAIN CLUB的超凡境地中,美食、美酒和美妙的音乐是智灵的洗净,像干燥的北京城迎来第一场春天的“润”——稍显奢华。[编者按] 相似文献
18.
Y Ohtsuka X-T Wang J Saito T Ishida M Munakata 《The European respiratory journal》2006,28(5):1013-1019
Inter-individual variations in the development of silicosis, even within the same environments, have been reported, which suggest the contribution of genetic factors in silicosis aetiology. The aim of the present study was to determine whether there is any significant genetic influence on the development of silicosis. Furthermore, which genetic loci are responsible for the pulmonary response to silica exposure? Eight strains of inbred mice were used to examine the genetic influence on the lung fibrotic response to silica exposure. After intercross-breeding between the most susceptible and most resistant strains, a genome-wide linkage analysis of quantitative trait loci (QTL) was performed. Hydroxyproline was applied as an index, and genotypes of 167 marker genes were analysed by fragment analysis using a capillary-type sequencer. There was significant inter-strain difference in the mean concentration of hydroxyproline contents among the eight strains of mice. Breeding studies were conducted between the most susceptible, C57BL/6J, and the most resistant strain, CBA/J. A genome-wide linkage analysis of silica-exposed intercrossed cohorts identified significant QTL on chromosome 4 and suggestive QTL on chromosomes 3 and 18. The present study demonstrates that genetic factors may play a significant role in fibrotic-lung responses to silica; one significant and two suggestive quantitative trait loci were identified. 相似文献
19.
20.