全文获取类型
收费全文 | 18314篇 |
免费 | 846篇 |
国内免费 | 121篇 |
专业分类
耳鼻咽喉 | 92篇 |
儿科学 | 301篇 |
妇产科学 | 131篇 |
基础医学 | 2216篇 |
口腔科学 | 296篇 |
临床医学 | 1194篇 |
内科学 | 4708篇 |
皮肤病学 | 407篇 |
神经病学 | 1356篇 |
特种医学 | 1081篇 |
外科学 | 3199篇 |
综合类 | 58篇 |
预防医学 | 579篇 |
眼科学 | 282篇 |
药学 | 1208篇 |
中国医学 | 62篇 |
肿瘤学 | 2111篇 |
出版年
2023年 | 111篇 |
2022年 | 216篇 |
2021年 | 412篇 |
2020年 | 220篇 |
2019年 | 309篇 |
2018年 | 349篇 |
2017年 | 334篇 |
2016年 | 388篇 |
2015年 | 405篇 |
2014年 | 546篇 |
2013年 | 652篇 |
2012年 | 1020篇 |
2011年 | 1147篇 |
2010年 | 646篇 |
2009年 | 558篇 |
2008年 | 936篇 |
2007年 | 1062篇 |
2006年 | 1047篇 |
2005年 | 1150篇 |
2004年 | 1105篇 |
2003年 | 1078篇 |
2002年 | 1067篇 |
2001年 | 428篇 |
2000年 | 424篇 |
1999年 | 433篇 |
1998年 | 279篇 |
1997年 | 204篇 |
1996年 | 207篇 |
1995年 | 167篇 |
1994年 | 149篇 |
1993年 | 147篇 |
1992年 | 221篇 |
1991年 | 188篇 |
1990年 | 200篇 |
1989年 | 171篇 |
1988年 | 155篇 |
1987年 | 135篇 |
1986年 | 130篇 |
1985年 | 126篇 |
1984年 | 79篇 |
1983年 | 92篇 |
1982年 | 50篇 |
1981年 | 39篇 |
1980年 | 32篇 |
1979年 | 65篇 |
1978年 | 42篇 |
1975年 | 43篇 |
1974年 | 37篇 |
1970年 | 34篇 |
1969年 | 27篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Keiichiro Kume Masahiro Yamasaki Ichiro Yoshikawa Makoto Otsuki 《Digestive endoscopy》2006,18(3):218-220
Background: Although bleeding is an unavoidable complication of endoscopic submucosal dissection (ESD), endoscopic hemostasis using an insulation‐tipped electrosurgical knife (IT) knife is impossible because an insulator is mounted at the tip of the knife. We have developed a new type of hood which could perform both coagulation and irrigation simultaneously. Methods: Our new device was fabricated by drilling a side hole in the cap portion of a conventional transparent hood followed by attaching a machined papillotomy knife to the exterior surface of the hole. Results: Our new hood was useful for hemorrhage during ESD using IT knife. Conclusions: With this method, endoscopic hemostasis using IT knife is easy, as hemostatic procedure can be performed under irrigation and coagulation using conventional endoscopy. 相似文献
2.
3.
Kensaku Maeda Kenichi Yasunari Eisuke F Sato Junichi Yoshikawa Masayasu Inoue 《Hypertension research》2003,26(12):999-1006
The involvement of oxidative stress in polymorphonuclear leukocytes (PMN) in the pathogenesis of hypertension remains to be elucidated. We analyzed the generation of reactive oxygen species (ROS) by the circulating and peritoneally infiltrating PMN from spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). Flow cytometric analysis revealed that ROS generation by PMN from SHR was higher than that from WKY before (at 6 weeks of age) and after (at 16 weeks of age) the onset of hypertension. In vivo, ROS generation by PMN from SHR, but not that by PMN from WKY, was significantly suppressed by 10-week treatment with 50 mg/kg/day carvedilol, and this treatment did not affect blood pressure. Western blotting analysis revealed that protein kinase C alpha (PKCalpha), but not PKCbetaI or betaII, was activated more strongly in PMN from SHR than in PMN from WKY. Furthermore, expression of p47phox of nicotinamide adenine dinucleotide phosphate oxidase, but not of p67phox, in PMN from SHR was higher than that in PMN from WKY. These results suggest that ROS generation by PMN is principally enhanced in SHR through activation of PKCalpha and p47phox. 相似文献
4.
Masayuki Amagai 《Nihon Rinshō Men'eki Gakkai kaishi》2006,29(5):325-333
To form the human body and maintain the integrity of its complex tissues, individual cells need to hold tightly to each other. The desmosome is the major type of intercellular adhesive junction, and has desmoglein (Dsg), a cadherin type cell-cell adhesion molecule, as a transmembrane component. Dsg is now known to be targeted in autoimmune diseases, infectious diseases, as well as inherited diseases. Patients with pemphigus, an autoimmune blistering disease of the skin and mucous membrane, have IgG autoantibodies directed against Dsg1 and Dsg3. A subset of patients with pemphigus have Dsg1/Dsg4 crossreacting IgG autoantibodies. Exfoliative toxins produced by Staphylococcal aureus, which causes Staphylococcal Scalded Skin Syndrome (SSSS) and bullous impetigo, specifically digest Dsg1. A subset of patients with SSSS develop a low titer of anti-Dsg1 IgG autoantibodies. A mutation in DSG1 gene causes striate palmoplantar keratoderma and a mutation in DSG4 gene causes inherited hypotrichosis. It is not clear why so many diseases are clustered in desmogleins, but there must be a reason for this. Studies on desmogleins will provide an important framework to understand the mysteries between autoimmunity and infection. 相似文献
5.
M Fukumizu T Kurokawa H Yoshikawa S Hanaoka 《No to hattatsu. Brain and development》1991,23(6):617-622
A seven-month-old girl with atypical West syndrome with pedaling automatism was reported. She started to have early infantile epileptic encephalopathy with suppression-burst (EIEE) at age 14 days followed by infantile spasms at 3 months of age. She began to have spasms with automatism at 4 month, mainly consisting of pedaling movements of both feet associated with tonic spasms of upper extremities and writhing of trunk. Ictal EEG showed irregular slow waves with occasional spikes predominantly over the right hemisphere mixed with artifacts. Interictal EEG during sleep showed suppression-burst patterns. Cerebral atrophy and microcephaly were revealed on brain CT, immature myelination on MRI and decreased blood flow in the frontal, temporal, and parietal lobes on the right on PET scan. Pedaling automatism is rare in infancy and its clinical significance was discussed in relation to West syndrome and complex partial seizures. 相似文献
6.
H Ikenaga T Ogihara S Iyori S Kou H Yoshikawa M M Okura 《Postgraduate medical journal》1989,65(768):761-764
A case of a young Japanese woman with long-standing ulcerative colitis complicated by preinfarction angina due to Takayasu's aortitis is presented. Successful emergency aorto-coronary bypass operation was performed. Whether the association of these two diseases can be explained by a common mechanism is discussed. 相似文献
7.
8.
OBJECTIVE: The aim of this study was to evaluate the relationship between the degree of conversion (DC) of composites and the light intensity using LED-curing units and also to determine the amount of exposure required to achieve optimal curing. METHOD: The light outputs of light-curing units and the depths of cure of composites exposed to these units were determined using the methods outlined in modified ISO standards, ISO/TS10650 and ISO 4049, respectively. The distributions of DC in composites were investigated by IR spectra of microareas obtained at various depths from the irradiated surface of thin specimens cut out from the cured composites. IR spectra were measured using a Fourier transform infrared spectrometer equipped with a microscopic unit. DC was calculated from the changes in the amount of C=C double bonds in the IR spectra. RESULTS: The light intensity at various depths through the cured composite was calculated from the attenuation coefficient of each material, obtained from the linear relationship between the depth of cure and the logarithm of the amount of exposure, which is defined as the product of the irradiance and irradiation time. There was a third or fourth order regression relationship between DC and the logarithm of total light energy at a particular depth. SIGNIFICANCE: The minimum light energy required to produce a saturated DC was about 1000 s mW/cm2. 相似文献
9.
Ryotaro Wake Masaaki Takeuchi Junichi Yoshikawa Minoru Yoshiyama 《Circulation journal》2007,71(7):1060-1066
BACKGROUND: Gender differences in the predictors of outcome among patients with known or suspected coronary artery disease (CAD) undergoing contrast-enhanced dobutamine stress echocardiography (CE-DSE) have not been completely determined. METHODS AND RESULTS: Follow-up (30+/-17 months) data for 581 men and 309 women with known or suspected CAD who underwent CE-DSE (mean age: 66 years) were obtained. Hard cardiac events included cardiac death and nonfatal myocardial infarction. Total cardiac events included hard cardiac events, unstable angina, congestive heart failure, and late revascularization (>3 months). Cardiac events occurred in 123 male and 50 female patients. Positive results for CE-DSE were associated with worse prognosis in both men and women (2-year total event free rate: 73.5% vs 88.2% in men, p<0.0001, 80.3% vs 91.3% in women, p<0.01). Addition of CE-DSE results, including abnormal left ventricular end-systolic volume response and left ventricular ejection fraction at peak stress <50%, to the clinical and rest echocardiography model provided incremental information for predicting total cardiac events (increase in chi-square value for the model from 60 to 72, p<0.001) in men and (increase in chi-square value for the model from 17 to 32, p<0.001) in women. CONCLUSIONS: CE-DSE provides incremental information for predicting future cardiac events in both men and women. 相似文献
10.
M Gotoh Y Yoshikawa T Otani T Kato M Kobayashi K Kato M Saito A Kondo K Miyake 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(12):1877-1883
Effects of adrenergic alpha-1-blocking agent, prazosin, in the treatment of detrusor external-sphincter dyssynergia (DSD) were evaluated in both experimental and clinical aspects. Experimentally, in the urethral pressure profile in dogs, the maximum urethral closing pressure was depressed after intravenous injection of 1 mg prazosin. When experimental DSD was obtained in dogs by stimulating electrically the unilateral 2nd sacral root, intra-venous injection of 1 mg prazosin inhibited contraction of the external urethral sphincter. Clinically, 74 patients with DSD based on neurogenic bladder from cerebral vascular attack (CVA) (13 cases) and spinal cord injury (61 cases) were retrospectively surveyed in terms of therapeutical effects of prazosin for DSD. Spinal cord injury was subdivided to 4 groups for clinical evaluation; cervical cord injury (C) with complete paralysis, thoracic cord injury (Th) with complete paralysis, lumbar cord injury (L) with complete paralysis and spinal cord injury with incomplete paralysis. Patients with CVA and spinal cord injury with incomplete paralysis showed good response rates in subjective improvement, 69% and 60% respectively. However, those with spinal cord injury with complete paralysis showed a poor response (28% for C, 23% for Th and 14% for L). The amount of residual urine significantly decreased after treatment, in all the groups except that of lumbar cord injury with complete paralysis. In all the groups, however, even after the drug treatment the amount of residual urine ranged from 80 to 170 ml and the rates of needing clean intermittent catheterization unchanged.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献