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81.
Effects of a high-selenium yeast supplement on celecoxib plasma levels: a randomized phase II trial.
Denise H Frank Denise J Roe H-H Sherry Chow Jose M Guillen Karin Choquette Debra Gracie Jennifer Francis Airley Fish David S Alberts 《Cancer epidemiology, biomarkers & prevention》2004,13(2):299-303
A combination of celecoxib and selenium was used in a randomized double-blind Phase II trial as a preliminary study to a multicenter Phase III colorectal cancer chemoprevention trial using these two agents together. The purpose of this trial was to determine whether high-selenium baker's yeast [(Saccharomyces cerevisiae) 200 microg once daily] in combination with celecoxib (400 mg once daily) altered the steady-state plasma concentration of celecoxib or produced clinically significant toxicities. Seventy-three healthy subjects (ages 40-75 years) were recruited to the 6-week study from the general local population and were randomized to either the celecoxib plus selenized baker's yeast group or the celecoxib plus placebo group after a 2-week run in period of celecoxib only. Blood samples were taken at baseline (to document that there was no evidence of celecoxib intake), after the 2-week run-in period on celecoxib to verify steady-state blood levels of this agent, and at end of study (4 weeks postrandomization). Toxicities were monitored at 2 weeks after initiation of celecoxib, at 4 weeks after initiation, and at the end of the study. Blood level concentrations of celecoxib did not differ between the two groups as determined by high-performance liquid chromatography analysis nor were there significant differences in blood chemistry values between the two groups. Subjects' self-report of general physical toxicities was uncommon and limited to National Cancer Institute toxicity grade 2 or less; however, 2 female participants (3%) were removed from the study medications because of grade 2 edema and significant weight gain after 2 and 2.5 weeks of celecoxib administration. In conclusion, high-selenium yeast and celecoxib can be taken at the described doses with minimum short-term negative effects. In future Phase III chemoprevention trials of celecoxib, weight gain should be carefully monitored, and participants should be made aware of this potential side effect before study entry. 相似文献
82.
Serologic evidence of human papillomavirus 16 and 18 infections and risk of prostate cancer. 总被引:2,自引:0,他引:2
Karin A Rosenblatt Joseph J Carter Lori M Iwasaki Denise A Galloway Janet L Stanford 《Cancer epidemiology, biomarkers & prevention》2003,12(8):763-768
Human papillomavirus (HPV) subtypes 16 and 18 are sexually transmitted and have been associated with an increased incidence of several anogenital tumors. Although previous epidemiological studies have suggested that sexual behaviors such as an early age at first intercourse and larger numbers of sexual partners are also related to an increased risk of prostate cancer, seroepidemiological studies of these infectious agents in relation to prostate cancer have produced differing results. To further evaluate this potential relationship, we completed a population-based control study in King County, Washington. Middle-aged (40-64 years) men diagnosed with prostate cancer (n = 642) were ascertained through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry between January 1993 and December 1996. Controls (n = 570) of similar age were selected from the same population as the cases by random digit dialing. Overall, there was no association between serological evidence of prior HPV-16 (adjusted odds ratio, 1.06; 95% confidence interval, 0.71-1.57) or HPV-18 (adjusted odds ratio, 1.36; 95% confidence interval, 0.69-2.69) infection and the risk of prostate cancer. Analyses of clinical features demonstrated no relationship between HPV infection status and Gleason score, stage of disease, or a combined measure of disease aggressiveness. Our findings indicate that HPV-16 and HPV-18 are not associated with prostate cancer risk. 相似文献
83.
A Systematic Overview of Radiation Therapy Effects in Cervical Cancer (Cervix Uteri) 总被引:2,自引:0,他引:2
Nina Einhorn Claes Trop Mona Ridderheim Karin Boman Bengt Sorbe Eva Cavallin-st hl 《Acta oncologica (Stockholm, Sweden)》2003,42(5):546-556
A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for cervical cancer is based on data from 1 meta-analysis and 34 randomized trials. In total, 35 scientific articles are included, involving 7 952 patients. The results were compared with those of a similar overview from 1996 including 34 024 patients. The conclusions reached can be summarized in these points: There are limited scientific data supporting that postoperative pelvic radiotherapy improves disease-free survival in early cervical cancer. No firm conclusion can be drawn.There is moderate scientific evidence that external beam radiotherapy combined with brachytherapy gives a similar disease-free and overall survival rate as radical hysterectomy in early cervical cancer.There is strong scientific evidence that concomitant radiochemotherapy improves disease-free and overall survival compared to radiotherapy alone in early cervical cancer.The NCI has recently published an announcement stating that cisplantin-based chemotherapy should be used concomitantly with radiotherapy in cervical cancer. No solid documentation for this statement can be found concerning locally advanced stages (>IIB).There is a strong scientific evidence that cisplatin-based chemotherapy given concomitantly with radiotherapy is superior to concomitant chemotherapy with hydroxyurea.There is no scientific evidence to show that neoadjuvant chemotherapy followed by radiotherapy improves disease-free or overall survival compared to radiotherapy alone in patients with localized cervical cancer.There is moderate scientific evidence that high-dose-rate brachytherapy gives the same local control rate as low-dose-rate brachytherapy but with fewer rectal complications. 相似文献
84.
Priv.-Doz.Dr. T. Kühn A. Bembenek H. Büchels T. Decker J. Dunst U. Müllerleile D. L. Munz H. Ostertag M. L. Sautter-Bihl H. Schirrmeister A. H. Tulusan M. Untch K. J. Winzer C. Wittekind 《Der Onkologe》2003,9(9):1011-1016
Die Sentinel-Lymphknotenbiopsie
(Sentinel-Node-Biopsie, SNB) ist ein diagnostisches Verfahren
beim Mammakarzinom, mit dem der Nodalstatus durch selektive
Entnahme und Untersuchung des (der) Lymphknoten mit der höchsten
Wahrscheinlichkeit für eine Metastasierung bestimmt wird.
Hauptziel der Methode ist eine vollständige Erfassung der
Patientinnen mit Lymphknotenmetastasen sowie die Vermeidung von
Morbidität durch eine Axilladissektion bei nodalnegativen
Frauen. Aufgrund der hohen Übereinstimmung zwischen dem
histologischem Status des
Sentinel-Nodes
und dem definitiven Nodalstatus (ermittelt durch
konventionelle Axilladissektion) stellt sich immer mehr die
Frage, ob und unter welchen Bedingungen die SNB als
Routineverfahren für das axilläre Staging gelten
kann. 相似文献
85.
CT-based delineation of lymph node levels and related CTVs in the node-negative neck: DAHANCA, EORTC, GORTEC, NCIC,RTOG consensus guidelines. 总被引:25,自引:0,他引:25
Vincent Grégoire Peter Levendag Kian K Ang Jacques Bernier Marijel Braaksma Volker Budach Cliff Chao Emmanuel Coche Jay S Cooper Guy Cosnard Avraham Eisbruch Samy El-Sayed Bahman Emami Cai Grau Marc Hamoir Nancy Lee Philippe Maingon Karin Muller Hervé Reychler 《Radiotherapy and oncology》2003,69(3):227-236
BACKGROUND AND PURPOSE: The appropriate application of 3-D CRT and IMRT for HNSCC requires a standardization of the procedures for the delineation of the target volumes. Over the past few years, two proposals--the so-called Brussels guidelines from Grégoire et al., and the so-called Rotterdam guidelines from Nowak et al.--emerged from the literature for the delineation of the neck node levels. Detailed examination of these proposals however revealed some important discrepancies. MATERIALS AND METHODS: Within this framework, the Brussels and Rotterdam groups decided to review their guidelines and derive a common set of recommendations for delineation of neck node levels. This proposal was then discussed with representatives of major cooperative groups in Europe (DAHANCA, EORTC, GORTEC) and in North America (NCIC, RTOG), which, after some additional refinements, have endorsed them. The objective of the present article is to present the consensus guidelines for the delineation of the node levels in the node-negative neck. RESULTS AND CONCLUSIONS: First a short discussion of the discrepancies between the previous Brussels and the Rotterdam guidelines is presented. The general philosophy of the consensus guidelines and the methodology used to resolve the various discrepancies are then described. The consensus proposal is then presented and representative CTVs that are consistent with these guidelines are illustrated on CT sections. Last, the limitations of the consensus guidelines are discussed and some concerns about the direct applications of these guidelines to the node-positive neck and the post-operative neck are described. 相似文献
86.
Tomas Norlander Sam-Hyun Kwon Gert Henriksson Karl Magnus Westrin Karin Sandstedt Pontus Stierna 《The Laryngoscope》1998,108(3):411-417
To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation. 相似文献
87.
M. Johansson A. Tommy Bergenheim Roland D’Argy Karin Edman Per-Olov Gunnarsson Anders Widmark Roger Henriksson 《Cancer chemotherapy and pharmacology》1998,41(4):317-325
Estramustine (EaM), a carbamate ester of 17β-estradiol and nor-nitrogen mustard, is a cytotoxic compound with antitumoral
effect in malignant glioma in vitro and in vivo . However, knowledge of the pharmacokinetics of EaM in experimental glioma
is limited. The objective of this study was therefore to investigate further the distribution of EaM in the BT4C rat glioma
model. Assessment of EaM uptake and distribution was performed by quantitative whole-body autoradiography. In addition, the
uptake of EaM and its metabolites estromustine (EoM), estradiol, and estrone were analyzed by gas chromatography. EaM was
taken up from the circulation and was found to be the main product in glioma tissue. Whole-body autoradiography after [14C]-EaM administration revealed a strong 14C label simultaneously in tumor and normal brain tissue at 0.5 h after drug administration. In tumor tissue, sustained high
levels of 14C label were detected at 12 h after drug administration. In contrast to the tumor, radioactivity in normal brain tissue rapidly
leveled off, indicating a retention of radioactivity in the tumor. The tumor/brain radioactivity ratio reached a peak of 4.5
at 12 h after drug administration. High levels of 14C label were also found in pulmonary tissue. By gas chromatography, EoM was found to be the main metabolite in plasma. However,
EaM reached higher levels in tumor tissue, with the mean tumor/plasma ratio being 11.7 as compared with 2.0 for EoM. Only
low plasma levels of the estrogen metabolites were detected. In conclusion, EaM is taken up in the BT4C rat glioma tissue
and is retained in the tumor as compared with normal brain tissue and plasma. EaM showed a greater selectivity for tumor tissue,
exhibiting a high tumor/plasma ratio as compared with EoM. The distribution pattern after administration of EaM, as evaluated
by both whole-body autoradiography and gas chromatography, supports the earlier suggestion that the uptake is related to a
protein with EaM-binding characteristics.
Received: 12 January 1997 / Accepted: 28 August 1997 相似文献
88.
Rosie Ashbolt Jenny Barralet Robert Bell Dennis Bittisnich Andrew Black Barry Combs Christine Carson Scott Crerar Craig Dalton Joy Gregory Michelle Harlock Gillian Hall Geoff Hogg Martyn Kirk Karin Lalor Tony Merritt Sally Munnoch Jennie Musto Lillian Mwanri Leonie Neville Chris Oxenford Rhonda Owen Jane Raupach Cameron Sault Russell Stafford Barbara Telfer Hassan Vally Kefle Yohannes 《Communicable diseases intelligence》2005,29(1):85-88
89.
Catharina Wising Jozef Azem Madeleine Zetterberg Liselott A Svensson Karin Ahlman Teresa Lagerg?rd 《Toxicon》2005,45(6):767-776
We investigated the impact of highly purified Haemophilus ducreyi cytolethal distending toxin (HdCDT) on the apoptosis and necrosis of various human cells; including myeloid cells, epithelial cells, keratinocytes, and primary fibroblasts. The levels of apoptosis and necrosis induced in these cells were compared to those induced by HdCDT in human T cells and in the Jurkat T cell line. Levels of caspase-3 activity were measured, and membrane changes like phosphatidylserine (PS) translocation was evaluated after double-staining with the fluorescein isothiocyanate (FITC)-labeled annexin V and propidium iodide (PI) using flow cytometry. HdCDT induced various degrees of apoptosis and necrosis in dose- and time-dependent manners in cells of various lineages. Early and late apoptosis (annexin V-stained cells) were induced in more than 90% of T cells and monocytes after treatment with 100 ng/ml HdCDT for 24 and 48 h, respectively. The corresponding numbers for epithelial cells, keratinocytes, and fibroblasts were 26-32% after treatment with 100 ng/ml HdCDT for 48 h. HdCDT appears to eliminate effectively by inducing apoptosis those cells that are involved in immune responses. Epithelial cells, keratinocytes and fibroblasts, which are important for the healing of chancroid ulcers, are eliminated by apoptosis or necrosis after contact with HdCDT, albeit slower and to a lesser extent than T cells. 相似文献
90.
A randomized, double-blinded study of remifentanil versus fentanyl for tonsillectomy and adenoidectomy surgery in pediatric ambulatory surgical patients 总被引:19,自引:0,他引:19
Davis PJ Finkel JC Orr RJ Fazi L Mulroy JJ Woelfel SK Hannallah RS Lynn AM Kurth CD Moro M Henson LG Goodman DK Decker MD 《Anesthesia and analgesia》2000,90(4):863-871
We compared, in a double-blinded manner, the anesthetic maintenance and recovery properties of remifentanil with a clinically comparable fentanyl-based anesthetic technique in pediatric ambulatory surgical patients. Anesthesia was induced with either halothane or sevoflurane and nitrous oxide and oxygen. Patients were randomized (computer generated) to receive either remifentanil or fentanyl in a blinded syringe with nitrous oxide and oxygen in one of four possibilities: halothane/remifentanil, halothane/fentanyl, sevoflurane/remifentanil or sevoflurane/fentanyl. In patients receiving remifentanil, a placebo bolus was administered, and a continuous infusion (0.25 microg. kg(-1). min(-1)) was begun. In patients receiving fentanyl, a bolus (2 microg/kg) was administered followed by a placebo continuous infusion. The time from discontinuation of the anesthetic to extubation, discharge from the postanesthesia care unit (PACU), and discharge to home, as well as pain scores, were assessed by a blinded nurse observer. Systolic blood pressure and heart rate were noted at selected times, and adverse events were recorded. Remifentanil provided faster extubation times and higher pain-discomfort scores. PACU and hospital discharge times were similar. There were no statistical differences among the groups for adverse events. There were statistically, but not clinically, significant differences in hemodynamic variables. We noted that continuous infusions of remifentanil were intraoperatively as effective as bolus fentanyl. Although patients could be tracheally extubated earlier with remifentanil, this did not translate to earlier PACU or hospital discharge times. In addition, remifentanil was associated with higher postoperative pain scores. The frequent incidence of postoperative pain observed in the postoperative recovery room suggests that better intraoperative prophylactic analgesic regimens for postoperative pain control are necessary to optimize remifentanil's use as an anesthetic for children. Implications: This is a study designed to examine the efficacy and safety of a short-acting opioid, remifentanil, when used in pediatric patients. The frequent incidence of postoperative pain observed in the postoperative recovery room suggests that better intraoperative prophylactic analgesic regimens for postoperative pain control are necessary to optimize remifentanil's use as an anesthetic for children. 相似文献