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91.
Dual role of vascular endothelial growth factor in hepatic ischemia-reperfusion injury 总被引:12,自引:0,他引:12
Tsurui Y Sho M Kuzumoto Y Hamada K Akashi S Kashizuka H Ikeda N Nomi T Mizuno T Kanehiro H Nakajima Y 《Transplantation》2005,79(9):1110-1115
BACKGROUND: Vascular endothelial growth factor (VEGF), a major angiogenic factor, mediates a variety of disease conditions through promotion of angiogenesis. It also plays a critical role as a potent proinflammatory cytokine in a variety of physiologic and pathologic immune responses. In the present study, we evaluated the expression of VEGF in hepatic warm ischemia-reperfusion (I/R) injury and examined the effect of recombinant human (rh)VEGF administration in an established murine model. METHOD: The expression of VEGF in the liver was assessed by quantitative real-time polymerase chain reaction and immunohistochemistry during I/R injury using 70% partial hepatic ischemia model. The effect of rhVEGF administration on I/R injury was evaluated by measuring liver function and histology. In addition, local inducible nitric oxide synthase (iNOS) and endothelial NO synthase expressions were examined to address the underlying mechanisms. RESULTS: The local expression of VEGF was significantly up-regulated at 2 hours after reperfusion after 60 minutes of ischemia compared with that in the naive liver. VEGF was expressed predominantly in CD11b+ cells infiltrating into the ischemic liver. The administration of rhVEGF had a significant protective effect on ischemic injury in the liver. This effect was associated with the up-regulation of iNOS expression in the rhVEGF-treated liver. CONCLUSION: We demonstrate a dual role of VEGF in hepatic warm I/R injury. Although endogenous VEGF is expressed and functional to initiate hepatic I/R injury, exogenous rhVEGF has a beneficial effect on the ischemic liver. These data may provide new insights into the role of VEGF as well as pathophysiology of hepatic I/R injury. 相似文献
92.
Ogawa E Takenaka K Katakura H Adachi M Otake Y Toda Y Kotani H Manabe T Wada H Tanaka F 《Annals of surgical oncology》2008,15(2):547-554
Purpose Aurora-A, also known as STK15/BTAK, is a member of the protein serine/threonine kinase family, and experimental studies have
revealed that Aurora-A plays critical roles in cell mitosis and in carcinogenesis. However, no clinical studies on Aurora-A
expression in non-small-cell lung cancer (NSCLC) have been reported. Thus, the present study was conducted to assess the clinical
significance of Aurora-A status.
Experimental Design A total of 189 consecutive patients with resected pathologic (p-)stage I-IIIA, NSCLC were retrospectively reviewed, and immunohistochemical
staining was used to detect Aurora-A expression.
Results Aurora-A expression was negative in 31 patients (16.4%); among Aurora-A positive patients, 124 patients showed pure diffuse
cytoplasmic Aurora-A expression and the other 34 patients showed perimembrane Aurora-A expression. Perimembrane Aurora-A tumors
showed the highest proliferative index (PI) (mean PIs for negative, diffuse cytoplasmic, and perimembrane tumors: 49.2, 41.7,
and 63.5, respectively; P < .001). Five-year survival rates of Aurora-A negative, diffuse cytoplasmic, and perimembrane patients were 67.8%, 66.7%,
and 47.6%, respectively, showing the poorest postoperative survival in perimembrane patients (P = .033). Subset analyses revealed that perimembrane Aurora-A expression was a significant factor to predict a poor prognosis
in squamous cell carcinoma patients, not in adenocarcinoma patients. A multivariate analysis confirmed that perimembrane Aurora-A
expression was an independent and significant factor to predict a poor prognosis.
Conclusions Perimembrane Aurora-A status was a significant factor to predict a poor prognosis in correlation with enhanced proliferative
activity in NSCLC. 相似文献
93.
Hiromichi Ito Michael Abramson Kaori Ito Edward Swanson Nancy Cho Daniel T. Ruan Richard S. Swanson Edward E. Whang 《Journal of gastrointestinal surgery》2010,14(5):891-898
Background
The aims of this study were to evaluate contemporary outcomes associated with the surgical management of pancreatic neuroendocrine tumors (PNETs) and to assess the prognostic value of the World Health Organization (WHO) classification and TNM staging for PNETs. 相似文献94.
Retrovirally mediated RNA interference targeting the M2 subunit of ribonucleotide reductase: A novel therapeutic strategy in pancreatic cancer 总被引:12,自引:0,他引:12
BACKGROUND: Ribonucleotide reductase M2 subunit (RRM2) overexpression enhances tumor chemoresistance and cellular invasiveness. We hypothesized that the RNA interference (RNAi) induced by retrovirally delivered small interfering RNA (siRNA) would sensitize pancreatic adenocarcinoma cells to gemcitabine and attenuate their invasive potential. METHODS: Stable suppression of RRM2 expression in PANC1, MIAPaCa2, BxPC3, and Capan2 cells was induced by exposure to a novel replication-deficient retrovirus, engineered to express RRM2-specific siRNA (psiRRM2), and confirmed by Western blot analysis. Single-base mismatch vector (psiControl) served as control. Ribonucleotide reductase activity was quantified, and gemcitabine 50% inhibitory concentrations were calculated. TUNEL staining and caspase profiling were performed after gemcitabine exposure. Cellular invasiveness was quantified in a Matrigel Boyden chamber. NF-kappaB activity and matrix metalloproteinase-9 (MMP-9) expression and activity were measured. RESULTS: RRM2 expression was stably and specifically suppressed in psiRRM2, but not psiControl transfectants. psiRRM2 transfectants exhibited lower 50% inhibitory concentrations, increased gemcitabine-induced apoptosis, and greater caspase-3 activation, relative to psiControl transfectants. Invasiveness was attenuated in psiRRM2 transfectants, as was NF-kappaB activity, MMP-9 expression, and MMP-9 activity, relative to psiControl transfectants. CONCLUSIONS: RRM2 gene silencing attenuates pancreatic adenocarcinoma cellular invasiveness and gemcitabine chemoresistance. Retroviral siRNA delivery can efficiently induce stable RNAi, allowing dissection of gene function and potentially representing a new therapeutic modality. 相似文献
95.
Koji Inui M.D. Hozumi Kawamoto M.D. Masahiko Kawakita M.D. Kazuhisa Wako M.D. Hiromichi Nakashima M.D. Masanori Kamihara M.D. Junichi Nomura M.D. 《Psychiatry and clinical neurosciences》1994,48(4):891-898
Abstract: The present study was designed to determine the clinical significance of a temporal low-voltage irregular delta wave (TLID) on EEG. Among 808 EEG records examined during one year at our hospital, the TLID was commonly detected in patients with clinically diagnosed ischemic brain diseases such as multiple infarction. Subsequently, a relation of the TLID to ischemic lesions on MRI was examined in 50 elderly depressive patients. It was found that there was a close correlation between the occurrence of the TLID and small ischemic lesions on MRI (p<0.001). These results suggest that the TLID is a valuable indicator of minor ischemic changes of the brain. 相似文献
96.
Miyuki Kohno Hiromichi Ikawa Kunio Konuma Hiroaki Masuyama Hironori Fukumoto Eri Ogawa Sadayoshi Takahashi Nozomu Kurose 《Surgery today》2010,40(3):281-284
Gastroenteric duplication rarely occurs in locations such as the pancreas. We report a case of gastroenteric duplication of
the pancreatic tail, which was noncontiguous with the stomach and had no communication with the pancreatic duct, in a 3-year-old
girl. The cyst was enucleated by laparoscopy, without the need for pancreatic resection. The optimal treatment procedures
vary considerably, depending on where the gastroenteric duplication is located in the pancreas and, most importantly, whether
there is communication with the pancreatic duct. 相似文献
97.
Intratumoral estrogens and estrogen receptors in human non-small cell lung carcinoma 总被引:2,自引:0,他引:2
Hiromichi Niikawa Takashi Suzuki Yasuhiro Miki Satoshi Suzuki Shuji Nagasaki Junichi Akahira Seijiro Honma Dean B Evans Shin-Ichi Hayashi Takashi Kondo Hironobu Sasano 《Clinical cancer research》2008,14(14):4417-4426
PURPOSE: The possible involvement of gender-dependent factors has been suggested in human non-small cell lung carcinomas (NSCLC), but their precise roles remain largely unclear. Therefore, we examined intratumoral estradiol concentrations in NSCLC to examine local actions of estrogens in NSCLC. EXPERIMENTAL DESIGN: Fifty-nine frozen specimens of NSCLC were available for liquid chromatography/electrospray tandem mass spectrometry to study intratumoral estradiol concentrations. In addition, A549 NSCLC cells stably expressing estrogen receptor (ER) alpha (A549 + ERalpha) or ERbeta (A549 + ERbeta) were used in vitro studies. RESULTS: Forty-three (73%) of 59 NSCLC showed higher concentration of estradiol in carcinoma tissues than the corresponding nonneoplastic lung tissues from the same patient, and intratumoral estradiol concentrations were significantly (P = 0.0002 and 2.2-fold) higher than the corresponding nonneoplastic lungs. The intratumoral concentration of estradiol was positively correlated with aromatase expression, tumor size, and Ki-67 status in ERalpha- or ERbeta-positive cases. In in vitro studies, estradiol significantly increased cell proliferation of A549 + ERalpha or A549 + ERbeta, which was significantly suppressed by selective ER modulators, tamoxifen or raloxifene. Both A549 + ERalpha and A549 + ERbeta cells expressed aromatase. The cell proliferation level in these cells was significantly increased under treatment with testosterone, and it was inhibited by addition of the aromatase inhibitor letrozole. CONCLUSIONS: These results suggest that estradiol is locally produced in NSCLC mainly by aromatase and plays an important role in the growth of ERalpha- or ERbeta-positive NSCLC. Therefore, use of selective ER modulators and/or aromatase inhibitors may be clinically effective in NSCLC that are positive for both ER and aromatase. 相似文献
98.
High Rates of Ki-ras Point Mutation in Both Intra- and Extra-hepatic Cholangiocarcinomas 总被引:2,自引:0,他引:2
Ohashi Kazuo; Tsutsumi Masahiro; Nakajima Yoshiyuki; Noguchi Osamu; Okita Shunji; Kitada Hiromichi; Tsujiuchi Toshifumi; Kobayashi Eisaku; Nakano Hiroshige; Yoichi Konishi 《Japanese journal of clinical oncology》1994,24(6):305-310
The presence of the Ki-ras gene mutations in 14 cases of intrahepaticcholangiocarcinoma (IHC) and nine cases of extrahepatic cholangiocarcinoma(EHC) were investigated by polymerase chain reaction-singlestrand conformation polymorphism analysis. To obtain enrichedtumor cell DNA, the microdissection method was used on formalin-fixedparaffin-embedded tissue sections. Point mutations at codon12 of the Ki-ras gene were detected in seven (50%) of the 14cases of IHC and six (67%) of the nine EHC cases. In all butone of the ras gene mutation cases, G to A transitions in thesecond position of codon 12 were detected, the exception beinga G to T transition in the same position in one IHC. No pointmutations were detected at codon 13 or 61 in either IHC or EHC.Furthermore, there was no demonstrable correlation between Ki-rasmutation and patient age, tumor Stage, histological findingsor prognosis. The present results demonstrated a higherparticipationof Ki-ras gene mutations in EHC than found in previous studies,and provided a confirmation and extension of the results earlierreported by Tada et al, and Tsuda et al, for IHC. 相似文献
99.
Toshifumi Tsujiuchi Eisaku Kobayashi Dai Nakae Yasushi Mizumoto Nobuaki Andoh Hiromichi Kitada Kazuo Ohashi Tomokazu Fukuda Akira Kido Masahiro Tsutsumi Ayumi Denda Yoichi Konishi 《Cancer science》1995,86(12):1136-1142
The effects of methionine on hepatocarcinogenesis induced by Coadministration of a choline-deflcient L-amino acid-defined (CDAA) diet and ethionine were examined. F344 male rats were divided into 4 experimental groups. Groups 1 and 2 received the CDAA diet and a choline-supplemented L-amino acid-defined (CSAA) diet, respectively. Group 3 received the CDAA diet containing 0.05% ethionine, and group 4 the CDAA diet containing 0.05% ethionine and 0.47% methionine. Animals were killed after 12 weeks of treatment. Histologically, the CDAA diet induced intracellular fat accumulation and foci. In contrast, ethionine caused not only foci, but also hyperplastic nodules, cholangiofibrosis and the proliferation of oval cells without such fat accumulation. Methionine abolished the development of all of the liver lesions induced by Coadministration of the CDAA diet and ethionine. To investigate the effects of methionine on induction of c- myc and c-Ha- ras expression, as well as generation of 8-hydroxyguanine (8-OHGua) and 2-thiobarbituric acid-reacting substances (TBARS), by Coadministration of the CDAA diet and ethionine, subgroups of 3 to 5 animals were killed at 2, 4, 8 or 11 days after the beginning of the experiment. Coadministration of the CDAA diet and ethionine markedly enhanced the level of expression of c- myc and c-Ha- ras , 8-OHGua formation and TBARS generation as compared with the CDAA or CSAA diet within 11 days, and methionine blocked these actions. These results indicate that addition of methionine prevents the induction of c- myc and c-Ha- ras expression, 8-OHGua formation and TBARS generation, as well as hepatocellular lesions, by Coadministration of the CDAA diet and ethionine in rats, and suggest a possible involvement of oxidative stress and gene expression in hepatocarcinogenesis by these agents. 相似文献
100.
Murata Tetsuya; Kuroda Hisaya; Nakahama Takayuki; Goshima Hiromichi; Shiraishi Taizo; Yatani Ryuichi 《Japanese journal of clinical oncology》1996,26(4):243-247
A case of primary non-Hodgkin lymphoma of the male breast isreported. The patient was a 76-year-old Japanese with a historyof bilateral gynecomastia. After the patient had received sexhormone treatment for the gynecomastia, rapid growth of a tumorin the right breast was noted, with regression of a contralateralbreast lesion. Clinically, inflammatory breast cancer was suspected,and right mastectomy with ipsilateral axillary lymph node dissectionwas performed after intraarterial infusion chemotherapy usinga cis-platinum derivative. The histology of the surgical specimenwas non-Hodgkin malignant lymphoma of the diffuse large celltype, with focal tumor necrosis. Immunohistochemically, thetumor cells showed a B-cell nature. The patient is currentlywell without disease 39 months after surgery. 相似文献