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991.
Shinsuke Koyama Masaki Kobayashi Yusuke Tanaka Masanori Isobe Hideaki Miwa Yasuhiko Shiki 《Journal of minimally invasive gynecology》2013,20(6):912-916
Among various long-term complications after previous myomectomy, increasing risk of uterine rupture or dehiscence during pregnancy, and in particular during labor, has been widely recognized. In contrast, the world literature includes no case report of spontaneous uterine perforation or rupture after myomectomy in a nonpregnant woman, and only 1 case of iatrogenic uterine perforation after uterine artery embolization has been reported. Recently, we encountered an extremely rare case of spontaneous uterine perforation after previous myomectomy accompanied by a bizarre tumor resembling polypoid endometriosis, which was successfully treated via laparoscopic surgery. The patient reported genital bleeding and lower abdominal pain. Preoperative magnetic resonance imaging and intraoperative findings clearly demonstrated the presence of a uterine wall defect and a multicystic tumor that had developed from the perforated portion of the uterus. The patient underwent successful laparoscopic surgery for repair of the perforated uterus and resection of the tumor. The clinicopathologic diagnosis of the tumor was tentatively confirmed as an endometriosis-like lesion resembling polypoid endometriosis. We speculate that the cause of the tumor was retrograde menstruation, as in the pathogenesis of endometriosis. 相似文献
992.
Shizuka Watanabe Yuriko Azami Miwa Ozawa Takahiro Kamiya Daisuke Hasegawa Chitose Ogawa Yasushi Ishida Ryota Hosoya Junko Kizu Atsushi Manabe 《Pediatrics international》2011,53(5):694-700
Background: The influence of central nervous system (CNS)‐directed chemotherapy on intelligence remains controversial. In this study, we investigated the influence of treatment on intellectual development in acute lymphoblastic leukemia (ALL) and brain tumor patients undergoing CNS‐directed treatments. Methods: Among patients treated in the Department of Pediatrics, St Luke's International Hospital between April 2000 and March 2009, the subjects were 38 patients with ALL or brain tumors who underwent regular Wechsler intelligence tests. Results: The subjects consisted of 26 patients with ALL and 12 with brain tumors. Prophylactic cranial irradiation was not performed in patients with ALL, whereas it was done for all those with brain tumor. In patients with ALL, the IQ 1 year later was not changed from the start of treatment. In those with brain tumors, the verbal IQ 1 year later was significantly lower than that at the start of treatment. In patients with ALL, intelligence tests were performed 3 years after the start of treatment and there were no marked changes between the two time‐points (n= 11). In those with a brain tumor, intellectual functions further decreased after the completion of treatment to as late as 5 years after the initiation of treatment (n= 7). Conclusions: There is no intellectual impairment in any patient with ALL at post‐treatment follow‐up 3 years after the start of treatment, while intelligence is serially reduced in brain tumor patients. An innovative intervention may be needed for this group of patients. 相似文献
993.
Taisuke Murata Kenta Miwa Fumiyasu Matsubayashi Kei Wagatsuma Kenta Akimoto Toshioh Fujibuchi Noriaki Miyaji Tomohiro Takiguchi Masayuki Sasaki Mitsuru Koizumi 《Annals of nuclear medicine》2014,28(7):617-622
Objective
High-energy beta emitters such as Strontium-89 (89Sr) and Yttrium-90 (90Y) are becoming increasingly popular nuclear therapy sources in Japan for treating cancer. Various characteristics of materials must be considered when designing radiation protection device for high-energy beta emitters. We empirically measured and simulated dose equivalents of beta and bremsstrahlung radiation arising from 89Sr and 90Y radiation shielded with various materials and determined optimal shielding materials against these sources.Methods
The dose equivalents of 89Sr and 90Y determined experimentally using an ionization chamber survey meter were compared with those of Monte Carlo simulations. The relative dose equivalents of beta and bremsstrahlung radiation separately transmitted by changing the thickness of acrylic, aluminum, iron, lead and tungsten shielding materials were simulated.Results
Dose equivalents were consistent between the empirical measurements and the simulation to within ±5 %. Shielding ability was more effective in the order of tungsten, lead, iron, aluminum and acrylic against both 89Sr and 90Y. The amount of beta and bremsstrahlung radiation transmitted through tungsten and lead was relatively small. Although such high-density material generates much bremsstrahlung radiation, it absorbs the bremsstrahlung radiations.Conclusions
Tungsten was the optimal material for efficient shielding against 89Sr and 90Y radiation and preferable among operators. The present findings provide useful information about how to define an appropriate shielding strategy for high-energy beta emitters. 相似文献994.
Induction of apoptosis in bovine articular chondrocyte by prostaglandin E(2) through cAMP-dependent pathway 总被引:5,自引:0,他引:5
Miwa M Saura R Hirata S Hayashi Y Mizuno K Itoh H 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2000,8(1):17-24
OBJECTIVE: Regulation of important biological processes such as proliferation and differentiation of articular chondrocytes is known to be mediated by prostaglandin E(2) (PGE(2)) in both normal and pathological states. Articular chondrocytes also undergo apoptosis, a biological phenomenon implicated in many physiological processes. Whether or not PGE(2) induces apoptosis in articular chondrocytes, however, is not known. DESIGN: Bovine articular chondrocytes were cultured with or without PGE(2) for 24 h and amounts of fragmented DNA, which is a distinct characteristic of apoptosis, were measured by enzyme-linked immunosorbent assay. Also effect of cyclic AMP (cAMP), which is one of the intracellular downstream mediator of PGE(2), on chondrocyte apoptosis was investigated. RESULTS: Administration of exogenous PGE(2) on bovine articular cartilage grown as a monolayer culture resulted in the induction of DNA fragmentation. This DNA fragmentation was accompanied with a marked dose-dependent increase in intracellular cAMP. Also cultured cells were treated with cAMP analogue, dibutyryl-cAMP or forskolin, a direct activator of adenylate cyclase, and the incidence of apoptosis in the chondrocytes was determined. As well as PGE(2), dibutyryl-cAMP and forskolin stimulated chondrocyte DNA fragmentation. CONCLUSIONS: It is the first report that PGE(2) can induce articular chondrocyte apoptosis in vitro. It is also suggest that apoptosis of chondrocytes by PGE(2) is linked with cAMP-dependent pathway. 相似文献
995.
Plasma platelet-activating factor acetylhydrolase deficiency is associated with atherosclerotic occlusive disease in japan 总被引:7,自引:0,他引:7
Unno N Nakamura T Kaneko H Uchiyama T Yamamoto N Sugatani J Miwa M Nakamura S 《Journal of vascular surgery》2000,32(2):263-267
PURPOSE: Plasma platelet-activating factor acetylhydrolase (PAF-AH) is known to catalyze platelet-activating factor, thereby inactivating its inflammatory function. Deficiency of this enzyme is caused by a missense (G(994)-->T) in exon 9 of the plasma PAF-AH gene. In this study, we investigated a possible association of this mutation with the risk of atherosclerotic occlusive disease (AO) in Japanese patients. METHODS: We studied 104 patients with AO. The control group consisted of 114 subjects matched for age and sex. Plasma PAF-AH activity was measured in the patients with AO. RESULTS: The prevalence of the mutant genotype (GT + TT ) was significantly more frequent in patients with AO than in control subjects (36.5% vs 23.7%; P <.05). Among the patients with AO, those with the mutant allele had significantly more risk factors of prior stroke or ischemic heart disease than patients with normal genotypes. Plasma PAF-AH activity was higher in patients with AO than in control subjects in normal genotype subgroups. CONCLUSIONS: The missense (G(994)-->T) in exon 9 of the plasma PAF-AH gene is associated with AO in Japanese people. 相似文献
996.
Takahiro Okada Noriko Kohyama Miki Takenaka Takashi Yamaguchi Tatsuya Kurihara Kosuke Sakurai Yusuke Miwa Mari Kogo 《Internal medicine (Tokyo, Japan)》2021,60(12):1827
Objective We aimed to develop a scoring model to predict a low disease activity (LDA) in elderly rheumatoid arthritis (RA) patients initially treated with biological disease-modifying antirheumatic drugs (bDMARDs). Methods This retrospective cohort study included 82 elderly RA patients who initially received bDMARDs. The outcome was an LDA after bDMARDs initiation. We developed a predictive formula for an LDA using a multivariate analysis, the accuracy of which was assessed by the area under the curve (AUC) of the receiver operating characteristic curves; the scoring model was developed using the formula. For each factor, approximate odds ratios were scored as an integer, divided into three groups based on the distribution of these scores. In addition, the scoring model accuracy was assessed. Results The mean age was 73.5±6.0 years old, and 86.6% were women. An LDA was achieved in 43 patients (52.4%). The predictive formula for an LDA was prepared using six factors selected for the multivariable analysis: the neutrophil-to-lymphocyte ratio (NLR), anemia, the 28-joint disease activity score with erythrocyte sedimentation rate (DAS28-ESR), serum level of matrix metalloproteinase-3 (MMP-3), diabetes mellitus (DM), and rheumatoid factor (RF). The AUC for the formula was 0.829 (95% confidence interval, 0.729-0.930). The odds ratios of the six factors were scored (DAS28-ESR and serum MMP-3=1 point, NLR, anemia, DM, and RF=2 points) and divided into three groups (≤4, 5-7, and ≥8). The high-score group (≥8) achieved a positive predictive value of 83%. Conclusion The scoring model accurately predicted an LDA in elderly RA patients initially treated with bDMARDs. 相似文献
997.
Tumor suppressor activity and inactivation of galanin receptor type 2 by aberrant promoter methylation in head and neck cancer 下载免费PDF全文
998.
Shingo Yonezawa Kazuhiro Miwa Jun Shinoda Yuichi Nomura Yoshitaka Asano Noriyuki Nakayama Naoyuki Ohe Hirohito Yano Toru Iwama 《Journal of neuro-oncology》2014,119(1):101-109
We investigated morphological and metabolic changes of radiation necrosis (RN) of the brain following bevacizumab (BEV) treatment by using neuroimaging. Nine patients with symptomatic RN, who had already been treated with radiation therapy for malignant brain tumors (6 glioblastomas, 1 anaplastic oligodendroglioma, and 2 metastatic brain tumors), were enrolled in this prospective clinical study. RN diagnosis was neuroradiologically determined with Gd-enhanced MRI and 11C-methionine positron emission tomography (MET-PET). RN clinical and radiological changes in MRI, magnetic resonance spectroscopy (MRS) and PET were assessed following BEV therapy. Karnofsky performance status scores improved in seven patients (77.8 %). Both volumes of the Gd-enhanced area and FLAIR-high area from MRI decreased in all patients after BEV therapy and the mean size reduction rates of the lesions were 80.0 and 65.0 %, respectively. MRS, which was performed in three patients, showed a significant reduction in Cho/Cr ratio after BEV therapy. Lesion/normal tissue (L/N) ratios in MET- and 11C-choline positron emission tomography (CHO-PET) decreased in 8 (89 %) and 9 patients (100 %), respectively, and the mean L/N ratio reduction rates were 24.4 and 60.7 %, respectively. BEV-related adverse effects of grade 1 or 2 (anemia, neutropenia and lymphocytopenia) occurred in three patients. These results demonstrated that BEV therapy improved RN both clinically and radiologically. BEV therapeutic mechanisms on RN have been suggested to be related not only to the effect on vascular permeability reduction by repairing the blood–brain barrier, but also to the effect on suppression of tissue biological activity, such as immunoreactions and inflammation. 相似文献
999.
Cyclin D1 overexpression correlates with poor prognosis in patients with tongue squamous cell carcinoma 总被引:5,自引:0,他引:5
Mineta H Miura K Takebayashi S Ueda Y Misawa K Harada H Wennerberg J Dictor M 《Oral oncology》2000,36(2):194-198
Tongue squamous cell carcinoma makes up a large percentage of head and neck cancers, and the incidence among young patients is increasing. The aim of this study was to reveal the correlation between cyclin D1 (CCND1) expression and clinical and histologic features. We performed an immunohistochemical study on the level of CCND1 expression in tumor specimens obtained from 94 patients with tongue squamous cell carcinoma. The relationship between the expression and the following features such as age, sex, smoking and alcohol intake history, T, N, histologic grade, and multiple primary cancer was analyzed. Eighteen patients (19%) showed CCND1 overexpression (tumor cell nuclei positivity >/=50%). The 5-year survival rate of high CCND1 expressors was 39%, which was significantly poor (p=0.04). N classification correlated with CCND1 expression. CCND1 overexpression is associated with poor survival associated with progression of lymph node spread in patients with tongue squamous cell carcinomas. CCND1 expression may be a useful biologic marker for prognosis. 相似文献
1000.
Suzuki T Ota T Maeda T Noshi Y Nakanishi S Okumura M Sanda Y Anno H Katada K 《Academic radiology》2008,15(8):1069-1074
RATIONALE AND OBJECTIVES: The latest multislice computed tomography (MSCT) scanners permit the chest and abdomen to be scanned continuously. However, conventionally, it has been necessary to perform scanning twice using different pitch factors for the cardiac and abdominal regions. We have developed a new scanning technique known as variable pitch factor scanning, in which the table speed is changed during scanning to obtain continuous images from the heart to the abdomen in a single scan, and have evaluated its physical characteristics. MATERIALS AND METHODS: A bead phantom, a comb phantom, and a gold wire placed at an angle were scanned using a 64-row MSCT scanner. The variation in the spatial resolution and continuity of images in the body axis direction because of changes in the pitch factor were evaluated. RESULTS: Because reconstruction taking the cone angle into consideration was employed, the spatial resolution in the body axis direction was unchanged and the continuity of images in the body axis direction was maintained at a certain level even when the pitch factor was changed. CONCLUSION: Variable pitch factor scanning is a useful technique for obtaining continuous images from the heart to the abdomen in a single scan. 相似文献