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排序方式: 共有7493条查询结果,搜索用时 15 毫秒
51.
Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy. 总被引:3,自引:0,他引:3
Ichiro Ogino Naoyuki Okamoto Yoshimi Ono Tatsuo Kitamura Hiroki Nakayama 《Radiotherapy and oncology》2003,68(1):61-67
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight. 相似文献
52.
Induction of apoptosis in multi-drug resistant (MDR) human glioblastoma cells by SN-38, a metabolite of the camptothecin derivative CPT-11 总被引:5,自引:0,他引:5
Shouji Nakatsu S. Kondo Yasuko Kondo Dali Yin John W. Peterson Rami Kaakaji Tatsuo Morimura Haruhiko Kikuchi Juji Takeuchi Gene H. Barnett 《Cancer chemotherapy and pharmacology》1997,39(5):417-423
The overexpression of the multidrug resistance (mdr1) gene and its product, P-glycoprotein (P-gp), is thought to limit the successful chemotherapy of human tumors. Recent studies
demonstrate that SN-38, a metabolite of the camptothecin (CPT) derivative CPT-11, has antitumor effects on several tumors,
but the mechanisms responsible for its cytotoxicity remain unclear. We therefore determined whether SN-38 has cytotoxic effects
on MDR human glioblastoma GB-1 cells and non-MDR human glioblastoma U87-MG cells. Furthermore, we determined what role SN-38
plays in the induction of cytotoxicity in these tumor cells. In this study, we demonstrated that SN-38 had significantly stronger
antitumor effects on GB-1 and U-87MG cells than did CPT (P<0.01 and P<0.05, respectively). In addition, findings obtained using a DNA fragmentation assay, Hoechst 33258 staining, in situ end-labeling
and cell cycle analysis demonstrated that SN-38 induced apoptosis in these tumors. Our results suggest that SN-38 has a stronger
antitumor effect on malignant glioma cells regardless of MDR expression than does CPT, and therefore can be considered a new
chemotherapeutic agent potentially effective in the treatment of human primary or recurrent malignant gliomas resistant to
chemotherapy.
Received: 6 October 1995/Accepted 29 June 1996 相似文献
53.
Association of Loss of Heterozygosity at the p53 Locus with Chemoresistance in Osteosarcomas 总被引:4,自引:0,他引:4
Akiteru Goto Hiroaki Kanda Yuichi Ishikawa Seiichi Matsumoto Noriyoshi Kawaguchi Rikuo Machinami Yo Kato Tomoyuki Kitagawa 《Cancer science》1998,89(5):539-547
Although the osteosarcoma is considered to be among the most chemosensitive malignancies and preoperative chemotherapy is commonly applied, an appreciable proportion of cases are in fact quite insensitive. Predictive markers for chemosensitivity are therefore desirable in order to develop effective treatment strategies. Thirty-two cases of conventional osteosarcomas treated at the Cancer Institute Hospital, Tokyo, were analyzed. The sensitivity to preoperative chemotherapy was investigated with reference to loss of heterozygosity (LOH) at the 17p13 ( p 53) and 13q14 ( Rb ) loci and expression of the cell-cycle associated proteins, p53, Rb, p21/Waf-1, mdm-2 and Ki-67, as detected immunohistochemically. LOH was detected by analyzing polymerase chain reaction products at marker microsatellite loci. The efficacy of chemotherapy was evaluated both radiologically and histologically. LOH at p 53 or Rb loci was seen in 54% (13/24) and 58% (14/24) of cases, respectively. Only 15% of osteosarcomas with LOH at the p 53 locus were sensitive to preoperative chemotherapy, as compared to 64% of tumors without such loss ( P <0.05). A similar but much less distinct tendency was observed with LOH at the Rb locus. No relationship was evident between chemosensitivity and immunohistochemical staining patterns for p53, Rb, p21/Waf-1, mdm-2 or Ki-67. The results suggest that p 53 gene deletion, but not the other parameters investigated, may be useful for predicting chemoresistance of osteosarcomas. 相似文献
54.
Kuwabara S Nishimaki T Komukai S Kanda T Suzuki T Hatakeyama K 《International surgery》2000,85(4):281-285
To explore the possible histogenesis of superficially spreading carcinoma of the esophagus, the clinicopathological features of these tumors (n = 44) were compared with those of ordinary superficial carcinoma (n = 163). Tumors of a heterogeneous histological type and having in situ carcinoma components were significantly more common (P < .05), and the number of residual squamous islands was significantly greater (P < 0.05) in the former group than the latter. Furthermore, the tumor size was not different among in situ, intramucosal, and submucosal carcinomas of the former, whereas the tumors became larger according to the depth of invasion in the latter group. These results indicate that the collision of multiple simultaneously developing superficial tumors is a plausible histogenesis of superficially spreading carcinoma of the esophagus. 相似文献
55.
Hiroyuki Shimizu i Utama Napa Onnimala Chen Li Zhang Li-Bi Ma Yu-Jie Yaowapa Pongsuwanna Tatsuo Miyamura 《Pediatrics international》2004,46(2):231-235
BACKGROUND: Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection. METHODS: Viruses were isolated from clinical samples from patients with HFMD or those with neurological complications. The EV71 isolates were identified by microneutralization assay. The VP4 and/or VP1 regions of recent EV71 isolates were sequenced and subjected to phylogenetic analysis using reference EV71 strains. RESULTS: The phylogenetic analysis of EV71 isolates from the WPR revealed two major genogroups, B and C, based on the nucleotide sequence alignment of the VP1 or VP4 region. These two major genogroups were further divided into subgenogroups, B1, B2, B3, and B4 and C1, C2, C3 and C4, respectively. CONCLUSIONS: The molecular epidemiological analyses of recent and previous EV71 isolates in the WPR indicated that two major genogroups of EV71 are co-circulating in Australia, Malaysia, Singapore, Taiwan and Japan. Recent EV71 isolates in Mainland China constitute a new distinct genetic cluster, subgenogroup C4. Two major lineages of EV71 are the major causative agents of the present HFMD epidemics in the WPR and both are considered to be neurovirulent. 相似文献
56.
57.
Takaaki Konuma Shohei Mizuno Tadakazu Kondo Yasuyuki Arai Naoyuki Uchida Satoshi Takahashi Masatsugu Tanaka Takuro Kuriyama Shigesaburo Miyakoshi Makoto Onizuka Shuichi Ota Yasuhiro Sugio Yasushi Kouzai Toshiro Kawakita Hikaru Kobayashi Yukiyasu Ozawa Takafumi Kimura Tatsuo Ichinohe Yoshiko Atsuta Masamitsu Yanada for the Adult Acute Myeloid Leukemia Working Group of the Japanese Society for Transplantation Cellular Therapy 《Blood cancer journal》2022,12(5)
Unrelated cord blood transplantation (CBT) is an alternative curative option for adult patients with acute myeloid leukemia (AML) who need allogeneic hematopoietic cell transplantation (HCT) but lack an HLA-matched related or unrelated donor. However, large-scale data are lacking on CBT outcomes for unselected adult AML. To investigate the trends of survival and engraftment after CBT over the past 22 years, we retrospectively evaluated the data of patients with AML in Japan according to the time period of CBT (1998–2007 vs 2008–2013 vs 2014–2019). A total of 5504 patients who received single-unit CBT as first allogeneic HCT for AML were included. Overall survival (OS) at 2 years significantly improved over time. The improved OS among patients in ≥ complete remission (CR)3 and active disease at CBT was mainly due to a reduction of relapse-related mortality, whereas among patients in first or second CR at CBT, this was due mainly to a reduction of non-relapse mortality. The trends of neutrophil engraftment also improved over time. This experience demonstrated that the survival and engraftment rate after CBT for this group has improved over the past 22 years.Subject terms: Acute myeloid leukaemia, Cancer immunotherapy 相似文献
58.
早产儿视网膜病变伴黄斑裂孔的视网膜脱离 总被引:2,自引:0,他引:2
目的:描述早产儿视网膜病变的黄斑裂孔视网膜脱离及其手术处理和疗效。方法:回顾性分析4例早产儿视网膜病变患儿和1例表现为早产儿视网膜病变的足月儿。均出现伴黄斑裂孔视网膜脱离并且接受手术治疗。结果:4例早产儿视网膜病变的平均孕周是26周。5例患儿发现黄斑裂孔前均有玻璃体手术史。4例再次手术治疗的患儿视网膜部分或完全复位。有走动的视力。结论:采用玻璃体手术合并气-液交换不能闭合婴儿中因早产儿视网膜病变引起视网膜脱离的黄斑裂孔。非热性黄斑部巩膜扣带术能封闭裂孔和复位视网膜。可能是值得选择的方法。 相似文献
59.
Fukushima-Uesaka H Saito Y Tohkin M Maekawa K Hasegawa R Kawamoto M Kamatani N Suzuki K Yanagawa T Kajio H Kuzuya N Yasuda K Sawada J 《Drug metabolism and pharmacokinetics》2007,22(1):48-60
Multidrug resistance-related protein 1 (MRP1), an ATP-binding cassette transporter encoded by the ABCC1 gene, is expressed in many tissues, and functions as an efflux transporter for glutathione-, glucuronate- and sulfate-conjugates as well as unconjugated substrates. In this study, the 31 exons and their flanking introns of ABCC1 were comprehensively screened for genetic variations in 153 Japanese subjects to elucidate the linkage disequilibrium (LD) profiles and haplotype structures of ABCC1 that is necessary for pharmacogenetic studies of the substrate drugs. Eighty-six genetic variations including 31 novel ones were found: 1 in the 5'-flanking region, 1 in the 5'-untranslated region (UTR), 20 in the coding exons (9 synonymous and 11 nonsynonymous variations), 4 in the 3'-UTR, and 60 in the introns. Of these, eight novel nonsynonymous variations, 726G>T (Trp242Cys), 1199T>C (Ile400Thr), 1967G>C (Ser656Thr), 2530G>A (Gly844Ser), 3490G>A (Val1164Ile), 3550G>A (Glu1184Lys), 3901C>T (Arg1301Cys), and 4502A>G (Asp1501Gly), were detected with an allele frequency of 0.003. Based on the LD profiles, the analyzed regions of the gene were divided into five LD blocks (Blocks -1 and 1 to 4). The multiallelic repeat polymorphism in the 5'-UTR was defined as Block -1. For Blocks 1, 2, 3 and 4, 32, 23, 23 and 13 haplotypes were inferred, and 9, 7, 7 and 6 haplotypes commonly found on > or = 10 chromosomes accounted for > or = 91% of the inferred haplotypes in each block. Haplotype-tagging single nucleotide polymorphisms for each block were identified to capture the common haplotypes. This study would provide fundamental and useful information for the pharmacogenetic studies of MRP1-dependently effluxed drugs in Japanese. 相似文献
60.
Bukowski R Uchida T Smith GC Malone FD Ball RH Nyberg DA Comstock CH Hankins GD Berkowitz RL Gross SJ Dugoff L Craigo SD Timor IE Carr SR Wolfe HM D'Alton ME;First Second Trimester Evaluation of Risk 《Obstetrics and gynecology》2008,111(5):1065-1076
OBJECTIVE: To demonstrate that individualized optimal fetal growth norms, accounting for physiologic and pathologic determinants of fetal growth, better identify normal and abnormal outcomes of pregnancy than existing methods. METHODS: In a prospective cohort of 38,033 singleton pregnancies, we identified 9,818 women with a completely normal outcome of pregnancy and characterized the physiologic factors affecting birth weight using multivariable regression. We used those physiologic factors to individually predict optimal growth trajectory and its variation, growth potential, for each fetus in the entire cohort. By comparing actual birth weight with growth potential, population, ultrasound, and customized norms, we calculated for each fetus achieved percentiles, by each norm. We then compared proportions of pregnancies classified as normally grown, between 10th and 90th percentile, or aberrantly grown, outside this interval, by growth potential and traditional norms, in 14,229 complicated pregnancies, 1,518 pregnancies with diabetes or hypertensive disorders, and 1,347 pregnancies with neonatal complications. RESULTS: Nineteen physiologic factors, associated with maternal characteristics and early placental function, were identified. Growth potential norms correctly classified significantly more pregnancies than population, ultrasound, or customized norms in complicated pregnancies (26.4% compared with 18.3%, 18.7%, 22.8%, respectively, all P<.05), pregnancies with diabetes or hypertensive disorders (37.3% compared with 23.0%, 28.0%, 34.0%, respectively, all P<.05) and neonatal complications (33.3% compared with 19.7%, 24.9%, 29.8%, respectively, all P<.05). CONCLUSION: Growth potential norms based on the physiologic determinants of birth weight are a better discriminator of aberrations of fetal growth than traditional norms. LEVEL OF EVIDENCE: II. 相似文献