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991.
992.
Reversal of the effect of albumin on gut barrier function in burn by the inhibition of inducible isoform of nitric oxide synthase 总被引:2,自引:0,他引:2
Chen LW Wang JS Hwang B Chen JS Hsu CM 《Archives of surgery (Chicago, Ill. : 1960)》2003,138(11):1219-1225
HYPOTHESIS: The use of albumin in the early resuscitation formula after major burn has been forbidden because of its damaging effect on the gut barrier function. We hypothesize that inhibition of the inducible isoform of nitric oxide synthase to stabilize endothelial permeability and to retain albumin in the vascular space will ameliorate the major trauma-induced gut barrier dysfunction. DESIGN, INTERVENTIONS, AND MAIN OUTCOME MEASURES: In experiment 1, specific pathogen-free rats undergoing 35% total body surface area burn or sham burn were given equal volumes (7.5 mL/kg) of isotonic sodium chloride solution or albumin from femoral veins for fluid resuscitation at 0, 4, or 8 hours after burn. In experiment 2, intraperitoneal S-methylisothiourea sulfate (7.5 mg/kg) was given immediately after burn to rats from different groups, as in experiment 1 (SMT groups). At 24 hours after burn, the intestinal mucosa was assayed for myeloperoxidase activity as an index for neutrophil sequestration, the distribution of fluorescein isothiocyanate-dextran across the lumen of small intestine was determined to evaluate the intestinal permeability, and bacterial translocation (BT) to the mesenteric lymph nodes (MLNs) and histological findings in the ileum were also examined. RESULTS: Compared with sham burn, burn induced significant increases in intestinal mucosa myeloperoxidase activity, intestinal permeability, BT to the MLNs, and villi sloughing in rats. Albumin administration at 0 or 4 hours after burn enhanced the increases in neutrophil sequestration, permeability, and villi sloughing compared with saline injection at the same times. In contrast, injection of albumin in the burn-SMT group did not aggravate these changes in intestinal myeloperoxidase activity, intestinal permeability, BT to the MLNs, and villi edema. Burn-SMT rats with albumin injections at 4 or 8 hours after burn showed significant 35% and 52% decreases, respectively, in intestinal permeability compared with burn-SMT-saline rats. Use of albumin at 8 hours after burn in combination with S-methylisothiourea significantly attenuated BT to the MLNs and reduced villi edema. CONCLUSIONS: Early albumin resuscitation aggravated the burn-induced gut damage. Albumin administration and inhibition of the inducible isoform of nitric oxide synthase in combination decreased burn-induced gut barrier dysfunction and reversed the damaging effect of albumin on gut barrier function and decreased BT. 相似文献
993.
Beltran J Matityahu A Hwang K Jbara M Maimon R Padron M Mota J Beltran L Sundaram M 《Skeletal radiology》2003,32(8):435-445
OBJECTIVE: To describe the normal MR anatomy and variations of the distal semimembranosus tendinous arms and the posterior oblique ligament as seen in the three orthogonal planes, to review the biomechanics of this complex and to illustrate pathologic examples. RESULTS AND CONCLUSION: The distal semimembranosus tendon divides into five tendinous arms named the anterior, direct, capsular, inferior and the oblique popliteal ligament. These arms intertwine with the branches of the posterior oblique ligament in the posterior medial aspect of the knee, providing stability. This tendon-ligamentous complex also acts synergistically with the popliteus muscle and actively pulls the posterior horn of the medial meniscus during knee flexion. Pathologic conditions involving this complex include complete and partial tears, insertional tendinosis, avulsion fractures and bursitis. 相似文献
994.
Soon-A Hwang Joon Beom Seo Byeong-Kyoo Choi Kyung-Hyun Do Sung Min Ko Soo-Hyun lee Jin Seong Lee Jae-Woo Song Koun-Sik Song Tae-Hwan Lim 《Korean journal of radiology》2003,4(3):153-156
Objective
To compare observer performance using liquid-crystal display (LCD) and cathode-ray tube (CRT) monitors in the interpretation of soft-copy chest radiographs for the detection of small solitary pulmonary nodules.Materials and Methods
By reviewing our Medical Center''s radiologic information system, the eight radiologists participating in this study (three board-certified and five resident) retrospectively collected 40 chest radiographs showing a solitary noncalcified pulmonary nodule approximately 1 cm in diameter, and 40 normal chest radiographs. All were obtained using a storage-phosphor system, and CT scans of the same patients served as the gold standard for the presence of a pulmonary nodule. Digital images were displayed on both high-resolution LCD and CRT monitors. The readers were requested to rank each image using a five-point scale (1 = definitely negative, 3 = equivocal or indeterminate, 5 = definitely positive), and the data were interpreted using receiver operating characteristic (ROC) analysis.Results
The mean area under the ROC curve was 0.8901±0.0259 for the LCD session, and 0.8716±0.0266 for the CRT session (p > 0.05). The reading time for the LCD session was not significantly different from that for the CRT session (37.12 and 41.46 minutes, respectively; p = 0.889).Conclusion
For detecting small solitary pulmonary nodules, an LCD monitor and a CRT monitor are comparable. 相似文献995.
Clinical usefulness of human cytomegalovirus antigenemia assay after kidney transplantation 总被引:9,自引:0,他引:9
Kim CK Song JH Kim SM Peck KR Oh W Huh W Kim YG Kim SJ Joh JW Lee NY Park CG Hwang ES Cha CY Oh HY 《Transplantation》2003,75(12):2151-2155
BACKGROUND: Human (H) cytomegalovirus (CMV) infections are a major cause of morbidity and mortality among kidney transplants. We performed a prospective study to evaluate the clinical usefulness of HCMV antigenemia assay for preemptive treatment after kidney transplantation. METHODS: A total of 100 patients were followed up by HCMV antigenemia assay at posttransplantation weeks 1, 3, 5, 7, 9, 13, 17, and 21. Asymptomatic patients with positive antigenemia were observed without specific antiviral therapy. RESULTS: Most patients had been given cyclosporine A- and prednisolone-based immunosuppressive therapy (99.0%) and were HCMV seropositive before transplantation (99.0%). A positive antigenemia assay was detected in 41 patients among 97 eligible patients. Symptomatic CMV diseases were observed in 10 of 41 patients. HCMV infections were related to history of acute rejection and use of antithymocyte globulin. HCMV-related symptoms and signs were clearly correlated with the level of antigenemia. All patients who had an HCMV antigenemia titer of higher than 50 per 400,000 leukocytes developed HCMV-related symptoms and signs during the follow-up period. This criterion showed the highest positive predictive value and specificity in the development of symptomatic HCMV infection. CONCLUSIONS: Data suggest that HCMV antigenemia titer can be used as a useful guide to preemptive treatment of HCMV infection after kidney transplantation in HCMV-positive donor and recipient. 相似文献
996.
Kim SP Hwang MS Cho YR Kwon SY Kang YN Kim IH Sohn SS Mun KC Kwon TK Lee SR Suh SI 《Cancer letters》2003,195(1):87-91
The bcl-2 homologue antagonist/killer (BAK) is a potently apoptosis-inducing gene and plays an important role in modulating apoptosis in epithelial cells. We have analyzed the mutation of the entire coding region of BAK gene in 107 Korean advanced gastric adenocarcinomas by polymerase chain reaction-single strand conformation polymorphism and sequencing. Homozygous deletions were not found in these samples. Only three cases of 107 gastric adenocarcinomas (2.8%) exhibited the BAK mutations. Two of them exhibited missense mutations and the remaining one had a silent mutation. All of these mutations were exclusively detected in exon 2. Mutations in the BAK gene were observed only in advanced gastric adenocarcinomas with extensive metastases of regional lymph nodes. The data presented here suggest that the mutations of BAK gene rarely occurred in advanced gastric adenocarcinomas. 相似文献
997.
998.
Kim JS Na CS Hwang WJ Lee BC Shin KH Pak SC 《The American journal of Chinese medicine》2003,31(3):481-488
As pregnancy advances, prostaglandins (PG) increase in the uterus, leading to elevated uterine contractility. Therefore, regulating the concentration of PG in the uterus can be a key factor for controlling the duration of labor. Since the synthesis of PGs in the uterus is catalyzed by cyclooxygenase-2 (COX-2), devising a tool to regulate the expression of COX-2 could provide a method for treating complicated labor. In this study, Sp-6 acupuncture treatment was evaluated for its potential in controlling uterine motility. Immunohistochemical methods showed the COX-2 enzyme was primarily found in the endometrium and myometrium of rat uterus. COX-2 expression in these two locations were intensified by pregnancy, but reduced by acupuncture at the Sp-6 acupoint. Uterine motility monitored during Sp-6 acupuncture was reduced by 28.15% (p < 0.05) and 19.88% (p < 0.05) in pregnant rats and non-pregnant rats, respectively. The significant reduction of uterine motility in pregnant rat suggests a role for Sp-6 acupuncture in regulating the expression of COX-2 during pregnancy. These results suggest that Sp-6 acupuncture could be used as a complementary method for controlling labor in human pregnancy. 相似文献
999.
Antioxidant activity of extracts from Alpinia katsumadai seed 总被引:5,自引:0,他引:5
Alpinia katsumadai (Zingiberaceae) has been widely used in traditional Chinese medicine to treat a variety of conditions such as emesis and gastric disorders. However, very little is known about the cellular actions by which this plant mediates its therapeutic effects. Various aspects of antioxidant activity were evaluated in a total extract derived from Alpinia katsumadai seed in this study. Relatively high levels of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were detected in the total extract (IC(50) 1.6 microgram/mL). Other known compounds such as (-)-epigallocatechine-3-gallate (EGCG) and resveratrol showed IC(50) values of <0.8 and 4.8 microgram/mL, respectively. The total extract also enhanced the viability of Chinese hamster lung fibroblast (V79-4) cells and inhibited H(2)O(2)-induced apoptosis. The total extract of Alpinia katsumadai also dose-dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79-4 cells, and these effects were comparable to other antioxidant compounds such as EGCG and resveratrol. Taken together, our findings show that Alpinia katsumadai contains significant antioxidant activity. 相似文献
1000.
Kuwanon G: an antibacterial agent from the root bark of Morus alba against oral pathogens 总被引:2,自引:0,他引:2
Kuwanon G was isolated from the ethyl acetate fraction of methanol extract of Morus alba and its structure was elucidated by 13C-NMR, 1H-NMR and FAB-MS. Antibacterial activity of kuwanon G was investigated by the minimum inhibitory concentration (MIC) test and the viable cell count method. MIC of kuwanon G against Streptococcus mutans causing dental caries was determined to be 8.0 microg/ml. The bactericidal test showed that kuwanon G completely inactivated S. mutans at the concentration 20 microg/ml in 1 min. Kuwanon G also significantly inhibited the growth of other cariogenic bacteria such as Streptococcus sobrinus and Streptococcus sanguis, and Porpyromonas gingivalis causing periodontitis. Transmission electron microscopy (TEM) of kuwanon G treated cells demonstrated remarkable morphological damage of the cell wall and condensation of the cytoplasm. 相似文献