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71.
Infection with the helminthic parasite, Strongyloides stercoralis, is usually acquired by skin invasion (or occasionally via ingestion of larvae). After transformation to the adult form, the parasite preferentially localises in the small intestine, especially in the duodenal and jejunal part. A remarkable feature of Strongyloides is its property of endogenous reinfection. In the case of an immunocompromised host a massive infection, called hyperinfections Strongyloides, may occur. Numerous gastrointestinal complications of strongyloides infections, sometimes with a lethal outcome, have been reported. The intestinal manifestations are usually limited to the small bowel, and rarely involve the stomach. We report a patient with complicated strongyloides infection of the stomach. 相似文献
72.
The effect of synthetic GnRH on the synthesis of proteins and glycoproteins in the anterior pituitary and in vitro release of LH into the medium was studied. A maximal dose (25 ng/ml) of of synthetic GnRH caused optimum release of radioimmunoassayable LH into the medium after 2 h of incubation. A concomitant increase in cyclic AMP accumulation in the tissue and LH in the incubation medium was also observed under the influence of GnRH during different periods of incubation time. Incubation of the rat anterior pituitary with GnRH stimulated the incorporation of [3H] proline into acid precipitable proteins in a time- and dose-dependent manner, similar to radioimmunoassayable LH released into the medium. Similar results were obtained when pituitary was incubated with dibutyryl cyclic AMP. LH, in addition, enhanced the incorporation of [3H] glucosamine and [3H] amino acids mixture into acid-precipitable proteins suggesting that proteins including glycoproteins are synthesized by the rat anterior pituitary under the influence of GnRH. Approximately 10% of the radioactivity associated with proteins comigrated with radioimmunoassayable LH on the gels. GnRH also enhanced the incorporation of [3H] glucosamine and [3H] amino acid mixture into immunoprecipitable LH. The GnRH-induced incorporation of [3H] proline into anterior pituitary proteins was abolished by specific translation inhibitors. 相似文献
73.
Expandable metal biliary stenting in patients with recurrent premature polyethylene stent occlusion 总被引:2,自引:0,他引:2
OBJECTIVES: Expandable metal stents are currently used to treat biliary tract obstruction. Few data exist on the role of metal stents in patients with recurrent premature plastic biliary stent occlusion. We report our preliminary results using an expandable metal biliary stent with enhanced stent flexibility in this group of patients. Our aim was to assess the efficacy of the Diamond biliary stent in the treatment of recurrent premature biliary plastic stent blockage. METHODS: From September 1997 to June 1998, six patients with inoperable biliary obstruction and at least one prior episode of plastic stent occlusion were treated with an expandable metal biliary prosthesis. There were four women and six men, with a mean age of 73+/-11 yr. Five patients had malignant biliary obstruction, and one inoperable patient had a biliary stricture secondary to chronic pancreatitis. Patients were followed-up prospectively until either stent occlusion or death. The patency duration of the metal stents was compared to that of the most recently placed plastic stents. RESULTS: All stents were successfully inserted endoscopically with visualized biliary drainage. No significant immediate postprocedural complications were noted. Median time from initial diagnosis of biliary obstruction to metal stent insertion was 35 wk (range 7-142), during which time patients had occluded a median of 4.5 plastic stents (range 2-5). Median patient survival was 117 days (15-312) and median time to blockage of the last plastic stent was 25.5 days (range 10-90 days). Three cases of metal stent occlusion occurred. One patient had early stent occlusion at 9 days because of debris and sludge clogging the metal stent. Two other patients developed stent occlusion at 120 and 157 days. Two stents remained patent until the patients' deaths at 15 and 87 days. Overall median stent patency was 139 days. The three patients who developed stent occlusion were treated with successful insertion of one or more plastic stents through the existing metal stent. Duration of metal stent patency was significantly longer than that of the last plastic stent (58.8 days longer; 95% CI [6.4, 111]; p = 0.03). CONCLUSIONS: Metal biliary prostheses represent an effective management strategy for recurrent plastic biliary stent obstruction. Patients in this subgroup may have a shorter duration of metal stent patency than the reported duration of stent patency in patients receiving initial metal stent placement. However the duration of patency still seems to be significantly longer than that of the most recently placed plastic stent. 相似文献
74.
Thrombospondin mediates the cytoadherence of Plasmodium falciparum- infected red cells to vascular endothelium in shear flow conditions 总被引:3,自引:0,他引:3
Rock EP; Roth EF Jr; Rojas-Corona RR; Sherwood JA; Nagel RL; Howard RJ; Kaul DK 《Blood》1988,71(1):71-75
Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria. 相似文献
75.
76.
Davis Victoria H. Nixon Stephanie A. Murphy Kathleen Cameron Cathy Bond Virginia A. Hanass-Hancock Jill Kimura Lauren Maimbolwa Margaret C. Menon J. Anitha Nekolaichuk Erica Solomon Patricia 《AIDS and behavior》2022,26(10):3386-3399
AIDS and Behavior - This scoping review assessed how the term ‘self-management’ (SM) is used in peer-reviewed literature describing HIV populations in low- and middle-income countries... 相似文献
77.
Kabundula Pelekelo P. Mbewe Esau G. Mwanza-Kabaghe Sylvia Birbeck Gretchen L. Mweemba Milimo Wang Bo Menon J. Anitha Bearden David R. Adams Heather R. 《AIDS and behavior》2022,26(10):3450-3450
78.
Sk Masum Billah Tarana E. Ferdous Patrick Kelly Camille Raynes-Greenow Abu Bakkar Siddique Nuzhat Choudhury Tahmeed Ahmed Stuart Gillespie John Hoddinott Purnima Menon Michael John Dibley Shams El Arifeen 《Maternal & child nutrition》2022,18(1):e13267
Adequate dietary diversity among infants is often suboptimal in developing countries. We assessed the impact of nutrition counselling using a digital job aid on dietary diversity of children aged 6–23 months using data from a cluster randomised controlled trial in Bangladesh. The trial had five arms, each with 25 clusters. The four intervention arms provided counselling using a digital job aid and different prenatal and post-natal combinations of lipid-based supplements and the comparison arm with usual practice. We enrolled 1500 pregnant women and followed them until the children reached their second birthday. We developed a tablet-based system for intervention delivery, data collection and project supervision. We combined the four intervention arms (n = 855), in which community health workers (CHWs) provided age-appropriate complementary feeding counselling, to compare against the comparison arm (n = 403). We calculated the outcome indicators from the children's 24-h dietary recalls. Overall, the intervention increased the mean dietary diversity score by 0.09 (95% confidence interval [CI]: 0.2–0.16) and odds of minimum dietary diversity by 18% (95% CI: 0.99–1.40). However, there was a significant interaction on the effect of the intervention on dietary diversity by age. The mean dietary diversity score was 0.24 (95% CI: 0.11–0.37) higher in the intervention than in the comparison arm at 9 months and 0.14 (95% CI: 0.01–27) at 12 months of age. The intervention effect was non-significant at an older age. Overall, consumption of flesh food was 1.32 times higher in the intervention arm (odds ratio [OR] 1.32, 95% CI: 1.11–1.57) in 6–23 months of age. The intervention significantly improved child dietary diversity score in households with mild and moderate food insecurity by 0.27 (95% CI: 0.06–0.49) and 0.16 (0.05–27), respectively, but not with food-secure and severely food-insecure households. Although the study did not evaluate the impact of digital job aid alone, the findings indicate the utility of nutrition counselling by CHWs using a digital job aid to improve child feeding practices in broader programmes. 相似文献
79.
Chromosome 17p deletions and p53 gene mutations associated with the formation of malignant neurofibrosarcomas in von Recklinghausen neurofibromatosis. 总被引:19,自引:3,他引:19 下载免费PDF全文
A G Menon K M Anderson V M Riccardi R Y Chung J M Whaley D W Yandell G E Farmer R N Freiman J K Lee F P Li et al. 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(14):5435-5439
von Recklinghausen neurofibromatosis (NF1) is a common hereditary disorder characterized by neural crest-derived tumors, particularly benign neurofibromas whose malignant transformation to neurofibrosarcomas can be fatal. The NF1 gene has been mapped to a small region of chromosome 17q, but neither the nature of the primary defect nor the mechanisms involved in tumor progression are understood. We have tested whether NF1 might be caused by the inactivation of a tumor suppressor gene on 17q, analogous to that on chromosome 22 in NF2, by searching for deletions of chromosome 17 in NF1-derived tumor specimens. Both neurofibrosarcomas from patients with "atypical" NF and 5 of 6 neurofibrosarcomas from NF1 patients displayed loss of alleles for polymorphic DNA markers on chromosome 17. However, the common region of deletion was on 17p and did not include the NF1 region of 17q. Since no loss of markers on chromosome 17 was observed in any of 30 benign tumors from NF1 patients, the 17p deletions seen in neurofibrosarcomas are probably associated with tumor progression and/or malignancy. This region contains a candidate gene for tumor progression, p53, which has recently been implicated in the progression of a broad array of human cancers. In a preliminary search for p53 aberrations by direct sequencing of polymerase chain reaction-amplified DNA from 7 neurofibrosarcomas, 2 tumors that contained point mutations in exon 4 of the p53 gene were found, suggesting a role for this gene in at least some neurofibrosarcomas. Thus the formation of malignant neurofibrosarcomas may result from several independent genetic events including mutation of the NF1 gene, whose mechanism of tumorigenesis remains uncertain, and subsequent loss of a "tumor suppressor" gene on 17p, most likely p53. 相似文献
80.
Mohanakrishnan L Vijayakumar K Sukumaran P Menon N Prabu CR Balaji S Manoharan S 《Asian cardiovascular & thoracic annals》2003,11(1):74-76
The recommended operative management of unruptured sinus of Valsalva aneurysm consists of closure of the mouth of the aneurysm with or without aortic valve surgery. We report a case of unruptured aneurysm producing right ventricular outflow tract obstruction. Closure of the mouth of the aneurysm failed to relieve the obstruction, which was subsequently achieved by excising the aneurysmal wall overlying the outflow tract. 相似文献