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81.
Takao Obara MD Yoshihide Fujimoto Reiko Tanaka Yukio Ito Takaya Kodama Tohru Yashiro Yoshiharu Kanaji Tomoyuki Yamashita Atsushi Fukuuchi 《Surgery today》1990,20(4):481-486
Although hyperfunctioning mediastinal parathyroid lesions that require median sternotomy or thoracotomy for removal are occasionally
present, the majority are located in the anterior mediastinum closely associated with the thymus. Only eight cases of ectopic
hyperfunctioning parathyroid tumors in the middle mediastinum have been reported. We experienced two cases of either persistent
or recurrent hyperparathyroidism in which abnormal parathyroid tissue was located in the aorticopulmonary window. One of the
patients had a parathyroid adenoma and the other had metastatic lesions of parathyroid carcinoma. In both cases, thallium
scanning proved useful in identifying the lesions while computed tomography scan was effective for mediastinal three-dimensional
localization. In one case, single photon emission computed tomography imaging with thallium proved beneficial for both identification
and localization of the middle mediastinal lesion. The surgical approach used in both cases was different. In one case, left
thoracotomy was performed, after which the ligamentum arteriosum was divided, and an adenoma anterior to the left main bronchus
and posterior to the left pulmonary artery removed. In the other case, two metastatic tumors of parathyroid carcinoma anterior
to the right main bronchus and posterior to the right pulmonary artery were resected through a median sternotomy and opening
of the pericardium. 相似文献
82.
Li-air batteries have attracted considerable attention as rechargeable secondary batteries with a high theoretical energy density of 11,400 kWh/g. However, the commercial application of Li-air batteries is hindered by issues such as low energy efficiency and a short lifetime (cycle numbers). To overcome these issues, it is important to select appropriate cathode materials that facilitate high battery performance. Carbon materials are expected to be ideal materials for cathodes due to their high electrical conductivity and porosity. The physicochemical properties of carbon materials are known to affect the performance of Li-air batteries because the redox reaction of oxygen, which is an important reaction for determining the performance of Li-air batteries, occurs on the carbon materials. In this study, we evaluated the effect of the surface modification of carbon cathode materials on the charge–discharge performance of Li-air batteries using commercial Ketjenblack (KB) and KB subjected to vacuum ultraviolet (VUV) irradiation as cathodes. The surface wettability of KB changed from hydrophobic to hydrophilic as a result of the VUV irradiation. The ratio of COOH and OH groups on the KB surface increased after VUV irradiation. Raman spectra demonstrated that no structural change in the KB before and after VUV irradiation was observed. The charge and discharge capacities of a Li-air battery using VUV-irradiated KB as the cathode decreased compared to original KB, whereas the cycling performance of the Li-air battery improved considerably. The sizes and shapes of the discharge products formed on the cathodes changed considerably due to the VUV irradiation. The difference in the cycling performance of the Li-air battery was discussed from the viewpoint of the chemical properties of KB and VUV-irradiated KB. 相似文献
83.
Hiroki Ochi Yasushi Hara Masahiro Tagawa Kenichi Shinomiya Yoshinari Asou 《Journal of orthopaedic research》2010,28(5):657-663
LPS (lipopolysaccharide), a major constituent of Gram‐negative bacteria, regulates proliferation and differentiation of osteoclasts directly or indirectly. This study sought to investigate the functions of the RANK/RANKL pathway in LPS‐induced bone loss in vivo. Wild‐type mice or TNFR1?/? mice were injected LPS with or without osteoprotegerin (OPG) and analyzed histologically. Bone volume was reduced by LPS injection in all groups, and OPG administration prevented the LPS‐induced bone loss regardless of genotypes. LPS‐induced enhancement of osteoclastogenesis in wild‐type mice was blocked by OPG administration. LPS or OPG did not affect osteoclastogenesis in TNFR1?/? mice. Interestingly, osteoblast surface was remarkably reduced in LPS‐treated TNFR1?/? mice as a result of enhanced osteoblast apoptosis. TRAIL, induced by TNF‐α in BMC, triggered apoptosis of primary osteoblast only when TNFR1 signal was ablated in vitro. In conclusion, RANK signaling plays a prominent role in osteoclastogenesis downstream of LPS. Furthermore, TNFR1 regulates bone metabolism through not only the regulation of osteoclast differentiation but also osteoblast survival. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:657–663, 2010 相似文献
84.
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86.
Akira Takada Kojiro Suzuki Yoshine Mori Ryota Hyodo Kenichi Kawakami Yoshiyuki Okochi Shinji Naganawa 《Journal of vascular and interventional radiology : JVIR》2013,24(4):550-557
PurposeTo compare left adrenal venous sampling (AVS) in two locations: the central adrenal vein and the common trunk.Materials and MethodsA total of 22 patients (12 men and 10 women; mean age, 50 y; range, 26–65 y) who were suspected of having primary aldosteronism (PA) and underwent successful AVS with cortisol concentration measurement and/or venography between November 2010 and August 2011 were retrospectively analyzed. In regard to the left adrenal vein, collections were done at two locations: at the common trunk below the confluence of the inferior phrenic vein and at the central adrenal vein, which was above the confluence. The effects of the inflow from the inferior phrenic vein on plasma aldosterone and cortisol levels were analyzed.ResultsEight patients had bilateral hypersecreting lesions and 13 had a unilateral lesion. One was diagnosed as having secondary hypertension other than PA. The median cortisol levels below and above the confluence were 129 μg/dL (range, 21–400 μg/dL) and 215 μg/dL (range, 21–690 μg/dL), respectively. The median aldosterone levels were 2,120 pg/mL (range, 164–42,700 pg/mL) and 4,275 pg/mL (range, 119–59,000 pg/mL), respectively. The median aldosterone/cortisol (A/C) ratios were 244 (range, 34–2,401) and 278 (range, 25–2,251), respectively. Cortisol and aldosterone levels were significantly higher above the confluence (P = .0050 and P = .0003, respectively), whereas the A/C ratio showed no significant difference (P = .12).ConclusionsAlthough higher levels of cortisol and aldosterone were obtained upstream, A/C ratio was not significantly different between the central adrenal vein and the common trunk. 相似文献
87.
88.
Wang W Yuasa T Tsuchiya N Maita S Kumazawa T Inoue T Saito M Ma Z Obara T Tsuruta H Satoh S Habuchi T 《Endocrine-related cancer》2008,15(4):943-952
Androgen-deprivation therapy (ADT) of patients with prostate cancer (PCa) is known to reduce bone mineral density (BMD). However, the most studies examined Caucasian or black patients and the effects of ADT on the bone metabolism of East Asians are unclear. Therefore, we performed a cross-sectional study to elucidate the influence of ADT on bone metabolism in Japanese patients. In total, 101 native Japanese patients with PCa were enrolled. They consisted of 58 ADT-treated and 43 hormone-naive patients. The BMD in the lumbar spine, total hip, and femoral neck was measured by dual energy X-ray absorptiometry and expressed in s.d. units relative to young adult men (T-score) or age-matched men (Z-score). Serum levels of bone metabolism markers were also measured. The BMDs at the three sites revealed that 2.3% (1/43) and 8.6% (5/58) of the hormone-naive and ADT-treated PCa patients had osteoporosis respectively, but this difference failed to achieve statistical significance (P=0.294). The two groups also did not differ significantly in their Z-scores of the three sites, and univariate and multivariate analyses indicated that ADT was not a significant risk factor for decreased BMD. In addition, a significant correlation between the duration of ADT and BMD was not observed for all three sites measured. However, the ADT-treated patients had significantly higher serum levels of N-terminal telopeptide of type I collagen (NTx) than the hormone-naive patients (P=0.017). To our knowledge, this is the first study to demonstrate the low prevalence of osteoporosis in both ADT-treated and hormone-naive Japanese PCa patients. Moreover, ADT did not significantly increase the prevalence of osteoporosis in this Japanese population. 相似文献
89.
Delayed Gastric Emptying by Helicobacter pylori Lipopolysaccharide in Conscious Rats 总被引:6,自引:0,他引:6
Toshikatsu Okumura Etsuro Shoji Nobuhiko Takahashi Hirokazu Wakebe Kenichi Imagawa Mikio Kikuchi Yutaka Kohgo 《Digestive diseases and sciences》1998,43(1):90-94
The present study was carried out to investigatethe possibility that lipopolysaccharide deprived fromHelicobacter pylori may alter gastric motility. Toaddress the question, we examined the effect of H. pylori lipopolysaccharide on gastricemptying in conscious rats. Gastric emptying wasevaluated by the phenol red method. Time-course anddose-related effects of intraperitoneal administrationof H. pylori lipopolysaccharide were investigated.Intraperitoneal injection of H. pylorilipopolysaccharide significantly suppressed gastricemptying of a liquid meal in a dose-dependent manner.The inhibitory action of H. pylori lipopolysaccharide wasobserved 2, 4, 8, or 12 hr after the injection. Theseresults suggest for the first time that H. pylorilipopolysaccharide may suppress gastric emptying in along-lasting fashion. It is also suggested that H. pylorimay influence gastric function through its cell wallstructure named lipopolysaccharide. 相似文献
90.
Trends in Asthma Mortality in Japan 总被引:3,自引:0,他引:3
Yuko Ito Akiko Tamakoshi Kenji Wakai Kenzo Takagi Kenichi Yamaki Yoshiyuki Ohno 《The Journal of asthma》2002,39(7):633-639
Asthma mortality has been increasing in many developed countries in recent years, so we have described the epidemiological features of asthma in Japan. Data on all certified asthma deaths from 1950 to 1997 were obtained from The National Vital Statistics, published annually by the Ministry of Health and Welfare. Trends in crude and age-adjusted asthma mortality rates, as well as age-specific mortality rates, were analyzed. Age and birth cohort effects on mortality rates were also examined using multiplicative models. Between 1950 and 1980, crude asthma mortality rates steadily decreased in both sexes and began to level off thereafter. Age-adjusted mortality rates have also decreased since 1950, and showed a persistent downward trend in both sexes even in recent years. Asthma mortality rates were higher in males than in females during the entire study period. When analysis was restricted to those aged 5 to 34 years, an upward trend since 1980 was observed. The multiplicative model showed a rapidly decreasing cohort effect on mortality among those born after 1860. However, the slope increased in the cohorts born after 1950 in both sexes. The age effect increased linearly with advancing age after 50 years in both sexes. Overall asthma mortality rates have been decreasing during the past five decades in Japan, but the mortality rate has increased among the 5-34-year-old age group since 1980. The high fatality rate stemming from the overuse of beta 2-agonists may account for the mortality increase. 相似文献