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991.
Mutation of the p53 tumor suppressor gene in spontaneously occurring osteosarcomas of the dog 总被引:8,自引:0,他引:8
Inactivation of the p53 tumor suppressor gene has been implicated in the
pathogenesis of numerous human cancers, including osteosarcomas.
Appendicular osteosarcomas of the dog appear to be a good model for their
human equivalent with regard to biologic behavior, epidemiology and
histopathology. We individually screened exons 5-8 of the p53 gene for
mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to
compare the role of this gene in human and canine osteosarcoma
tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with
one tumor possessing two mutations within different exons. Of these, seven
were missense mutations and the eighth was a 'silent' mutation potentially
affecting the exon 6-7 splicing region. Five of the missense mutations were
located in highly conserved regions IV and V, while another corresponded
with the highly conserved codon 220 mutational hotspot located outside the
conserved domains. The locations and types of mutations were nearly
identical to those reported in human cancer. These findings provide strong
evidence of the involvement of p53 mutations in the development of canine
appendicular osteosarcomas. Canine osteosarcomas appear to be a promising
model for their human equivalent on a clinical, pathologic, and molecular
level.
相似文献
992.
Anthony T. C. Chan Thomas W. T. Leung Wing H. Kwan Tony S. K. Mok Winnie Yeo Maria Lai Philip J. Johnson 《Cancer chemotherapy and pharmacology》1998,42(3):247-249
Purpose: A single-institution phase II trial of Temodal (temozolomide, SCH52365) in Chinese patients with advance nasopharyngeal
carcinoma was undertaken to determine the efficacy and safety of the drug in this population. Methods: A total of 14 patients with metastatic or locoregionally recurrent nasopharyngeal carcinoma were entered into the study.
One patient was unevaluable. Temodal was given at doses of 150 or 200 mg/m2 daily on days 1–5 every 28 days. Results: In all, 30 cycles of Temodal were given with no significant toxicity. All 13 (100%) evaluable patients had progressive disease
after 2 (84.6%) or 4 (15.4%) courses. Conclusion: Temodal given on this schedule has no activity in advanced nasopharyngeal carcinoma.
Received: 9 January 1998 / Accepted: 4 February 1998 相似文献
993.
994.
995.
Plasma from pre-eclamptic women and functional change in myometrial resistance arteries 总被引:1,自引:0,他引:1
Janet R. Ashworth Specialist Registrar Averil Y. Warren Chief Technician Ian R. Johnson Professor Philip N. Baker Senior Lecturer 《BJOG : an international journal of obstetrics and gynaecology》1998,105(4):459-461
This study assesses the ability of plasma from women with pre-eclampsia to induce altered endothelial function in myometrial resistance vessels from normotensive women. Vessels from normotensive pregnant women (n= 7) were incubated with plasma from other pregnant women who were normotensive (n= 6)or had pre-eclampsia (n= 7). A wire myograph was used to test the endothelium-dependent relaxatory response to bradykinin of preconstricted vessels. The relaxation in vessels incubated with plasma from women with pre-eclampsia was markedly less than in vessels incubated with plasma from normotensive pregnant women ( P = 0.039 ). This supports the theory that a plasma-borne factor contributes to the endothelial changes seen in pre-eclampsia. 相似文献
996.
Onome Ogueh Lecturer Gautam Khastgir Subspeciality Trainee John W. W. Studd Consultant Julia Jones Senior Scientist † Jamshid Alaghband-Zadeh Reader † Mark Richard Johnson Senior Lecturer 《BJOG : an international journal of obstetrics and gynaecology》1998,105(5):551-555
Objective To assess the risk of maternal osteoporosis associated with antenatal corticosterioid administration for neonatal respiratory distress syndrome prophylaxis.
Design Prospective longitudinal study.
Setting Maternity unit of Chelsea and Westminster Hospital, London.
Population Fourteen pregnant women who received dexamethasone therapy for fetal lung maturation in anticipation of delivery before 34 completed weeks of gestation.
Methods Blood samples were collected before dexamethasone administration, 24 hours and 48 hours after the course of dexamethasone, and within 24 hours of delivery. Serum levels of carboxy terminal pro-peptide of type I pro-collagen (PICP) were measured to monitor the rate of bone formation, and serum levels of cross-linked carboxy terminal telopeptide (ICTP) were measured as a marker of bone resorption.
Main outcome measures Changes in the markers of bone turnover following dexamethasone administration.
Results Serum PICP levels dropped 24 hours after dexamethasone therapy ( P = 0.001 ), but partially recovered by 48 hours ( P = 0.014 ) to reach higher than pre-therapy levels at delivery ( P = 0.044 ). Although there were no corresponding changes in the serum levels of ICTP after 24 and 48 hours of therapy, levels increased from pretherapy to delivery ( P = 0.006 ).
Conclusion Antenatal corticosteroid therapy leads to a transient suppression of, followed by an increase in, bone formation without any significant alteration in the pattern of bone resorption expected during pregnancy. 相似文献
Design Prospective longitudinal study.
Setting Maternity unit of Chelsea and Westminster Hospital, London.
Population Fourteen pregnant women who received dexamethasone therapy for fetal lung maturation in anticipation of delivery before 34 completed weeks of gestation.
Methods Blood samples were collected before dexamethasone administration, 24 hours and 48 hours after the course of dexamethasone, and within 24 hours of delivery. Serum levels of carboxy terminal pro-peptide of type I pro-collagen (PICP) were measured to monitor the rate of bone formation, and serum levels of cross-linked carboxy terminal telopeptide (ICTP) were measured as a marker of bone resorption.
Main outcome measures Changes in the markers of bone turnover following dexamethasone administration.
Results Serum PICP levels dropped 24 hours after dexamethasone therapy ( P = 0.001 ), but partially recovered by 48 hours ( P = 0.014 ) to reach higher than pre-therapy levels at delivery ( P = 0.044 ). Although there were no corresponding changes in the serum levels of ICTP after 24 and 48 hours of therapy, levels increased from pretherapy to delivery ( P = 0.006 ).
Conclusion Antenatal corticosteroid therapy leads to a transient suppression of, followed by an increase in, bone formation without any significant alteration in the pattern of bone resorption expected during pregnancy. 相似文献
997.
丹参酮对2型糖尿病高C反应蛋白的作用 总被引:3,自引:0,他引:3
目的 评价丹参酮对2型糖尿病高C反应蛋白(CRP)的作用。方法 将5 2例2型糖尿病CRP增高患者随机分2组各2 6例,均予常规降糖治疗,治疗组加服丹参酮4片/次,每天3次。共治疗3个月,比较2组治疗前及治疗后CRP水平。结果 治疗组CRP下降较对照组明显,P <0 .0 5。结论 丹参酮可明显降低CRP水平,可抑制2型糖尿病炎症反应。 相似文献
998.
目的:观察黔产习见蓼水提物(AE-P)的利尿、止血、镇痛药理作用及急性毒性。方法:测定NS负荷大鼠的排尿量及尿中Na+,K+,Cl-的含量;小鼠断尾出血时间(BT)及血浆复钙时间(RT);ip醋酸致小鼠扭体反应及热板致痛的潜伏期;LD50等指标。结果:AE-P能明显增加大鼠尿量和尿中Na+,K+,Cl-含量,且ig2次/d,连续给药7d,利尿作用无耐受性产生;AE-P能明显缩短小鼠BT和RT;能明显抑制小鼠扭体反应及延长热致痛潜伏期。AE-P以5g/kg(相当于干燥原生药80.64g/kg)给小鼠24hig3次,观察10d,小鼠全部存活;ip给药,其小鼠LD50为(3.13±0.39)g/kg(相当于干燥原生药50.48g/kg)。结论:AE-P具有利尿、止血及镇痛药理作用,其利尿作用不易产生耐受性,而止血作用与影响内凝系统有关,且毒性较低。 相似文献
999.
PURPOSE: Lung cancer is the leading cause of cancer deaths in the United States. Non-small-cell lung cancer (NSCLC) accounts for 75% to 85% of lung cancers. CT has been the standard anatomic study for localizing and staging NSCLC, although it is associated only with moderate accuracy. In-111 pentetreotide, a radiolabeled somatostatin analog largely used in the scintigraphic localization of neuroendocrine tumors, has been shown incidentally to identify NSCLC lesions. This observation is important in the workup for metastatic disease for neuroendocrine tumors, because presumed metastatic lesions may actually be second primary tumors of NSCLC. In-111 may also serve as a potentially useful adjunct to CT in the anatomic evaluation of NSCLC. The purpose of this study was to determine the likelihood of detecting and localizing NSCLC using In-111 pentetreotide scintigraphy. MATERIALS AND METHODS: Ten patients with known or possible NSCLC were examined using In-111 pentetreotide. Scans were compared with the patients' previously performed chest radiographs and CT scans. RESULTS: In-111 pentetreotide imaging correctly identified sites of tumor involvement as detected by chest CT and surgery in all 10 patients with NSCLC. CONCLUSION: This study demonstrates the uptake of In-111 pentetreotide by NSCLC. This important observation should be considered in the workup for metastatic disease of neuroendocrine tumors with In-111 pentetreotide, because NSCLC can be a source of false-positive findings. In-111 pentetreotide imaging may also serve as a potentially useful adjunct to CT for identifying obscured or equivocal lesions and as an aid in localizing tissue for biopsy. 相似文献
1000.
海尔福口服液驱铅效果的实验研究 总被引:1,自引:1,他引:1
目的观察中药海尔福口服液降低铅染毒小鼠血铅含量的效果。方法将80只雄性35 d昆明种小鼠分成4组:海尔福口服液组,大蒜提取物组,中毒不治疗组,正常对照组。以醋酸铅水溶液腹腔注射造模,2周后用中药海尔福口服液和大蒜提取液进行驱铅治疗,测定实验前、后小鼠体质量和血红蛋白(Hb)含量,检测实验后小鼠血铅含量。结果海尔福口服液组和大蒜提取物组小鼠的体质量和Hb含量比中毒不治疗组升高,血铅含量比中毒不治疗组明显降低。结论中药海尔福口服液具有驱铅功效。 相似文献