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91.
M. Dosemeci I. Gokmen M. Unsal R. B. Hayes A. Blair 《Cancer causes & control : CCC》1997,8(5):729-737
Effects of tobacco smoking and alcohol use on risks of cancers of thelarynx and lung have been evaluated extensively in industrialized countries.Few studies on the effect of these risk factors have been reported fromdeveloping countries. We conducted a case-control study to evaluate risks oflaryngeal and lung cancers in men by subsite and cell type in relation tosmoking and alcohol drinking in Turkey, a country where smoking and alcoholconsumption patterns are different from those in industrialized countries. Weidentified 832 laryngeal and 1,210 lung cancer cases and 829 controls withinformation on smoking and alcohol use (amount and duration) and histologiccell type from an oncology treatment center of a Social Security Agencyhospital in Istanbul, Turkey, admitted between 1979 and 1984. Both laryngealand lung cancer showed significant associations with smoking and alcoholdrinking, but no monotonic dose-response was obtained for alcohol drinking.Among smokers, the highest risks were observed in the supraglottis region ofthe larynx (odds ratio [OR] = 4.1) after adjustment for age and alcohol use.Among alcohol drinkers, the highest risks were observed in the glottis regionof the larynx (OR = 1.7) after adjustment for age and smoking. In theanalysis by the cell type of lung cancer among ever-smokers, small cell typeshowed the highest risk (OR = 5.4), while it showed no association withalcohol drinking. Cumulative cigarette use (pack-years) and number ofcigarettes per day showed stronger associations than years smoked for bothcancer sites. The relative risks of joint exposure to smoking and alcoholwere 12.2 for laryngeal cancer and 14.1 for lung cancer among heavy smokersand heavy alcohol drinkers. This study provides epidemiologic evidence fromTurkey that smoking and alcohol use are associated with risks of cancers ofthe larynx and lung. 相似文献
92.
Hemoglobin and albumin adducts of benzene oxide among workers exposed to high levels of benzene 总被引:3,自引:0,他引:3
Yeowell-O'Connell K; Rothman N; Smith MT; Hayes RB; Li G; Waidyanatha S; Dosemeci M; Zhang L; Yin S; Titenko-Holland N; Rappaport SM 《Carcinogenesis》1998,19(9):1565-1571
Benzene oxide (BO) reacts with cysteinyl residues in hemoglobin (Hb) and
albumin (Alb) to form protein adducts (BO-Hb and BO-Alb), which are
presumed to be specific biomarkers of exposure to benzene. We analyzed
BO-Hb in 43 exposed workers and 42 unexposed controls, and BO-Alb in a
subsample consisting of 19 workers and 19 controls from Shanghai, China, as
part of a larger cross-sectional study of benzene biomarkers. The adducts
were analyzed by gas chromatography-mass spectrometry following reaction of
the protein with trifluoroacetic anhydride and methanesulfonic acid. When
subjects were divided into controls (n = 42) and workers exposed to < or
=31 (n = 21) and >31 p.p.m. (n = 22) benzene, median BO-Hb levels were
32.0, 46.7 and 129 pmol/g globin, respectively (correlation with exposure:
Spearman r = 0.67, P < 0.0001). To our knowledge, these results
represent the first observation in humans that BO-Hb levels are
significantly correlated with benzene exposure. Median BO-Alb levels in
these 3 groups were 103 (n = 19), 351 (n = 7) and 2010 (n = 12) pmol/g Alb,
respectively, also reflecting a significant correlation with exposure
(Spearman r = 0.90, P < 0.0001). The blood dose of BO predicted from
both Hb and Alb adducts was very similar. These results clearly affirm the
use of both Hb and Alb adducts of BO as biomarkers of exposure to high
levels of benzene. As part of our investigation of the background levels of
BO-Hb and BO-Alb found in unexposed persons, we analyzed recombinant human
Hb and Alb for BO adducts. Significant levels of both BO-Hb (19.7 pmol/g)
and BO-Alb (41.9 pmol/g) were detected, suggesting that portions of the
observed background adducts reflect an artifact of the assay, while other
portions are indicative of either unknown exposures or endogenous
production of adducts.
相似文献
93.
Increased aneusomy and long arm deletion of chromosomes 5 and 7 in the lymphocytes of Chinese workers exposed to benzene 总被引:4,自引:1,他引:4
Zhang L; Rothman N; Wang Y; Hayes RB; Li G; Dosemeci M; Yin S; Kolachana P; Titenko-Holland N; Smith MT 《Carcinogenesis》1998,19(11):1955-1961
Two of the most common cytogenetic changes in therapy- and chemical-
related leukemia are the loss and long (q) arm deletion of chromosomes 5
and 7. The detection of these aberrations in lymphocytes of individuals
exposed to potential leukemogens may serve as useful biomarkers of
increased leukemia risk. We have used a novel fluorescence in situ
hybridization (FISH) procedure to determine if specific aberrations in
chromosomes 1, 5 and 7 occur at an elevated rate in the blood cells of
workers exposed to benzene. Forty-three healthy workers exposed to a wide
range of benzene concentrations (median 31 p.p.m., 8 h time-weighted
average) and 44 unexposed controls from Shanghai were studied. Whole blood
was cultured and metaphase spreads were harvested at 72 h. Benzene exposure
was associated with increases in the rates of monosomy 5 and 7 but not
monosomy 1 (P < 0.001, P < 0.0001 and P = 0.94, respectively) and
with increases in trisomy and tetrasomy frequencies of all three
chromosomes. Long arm deletion of chromosomes 5 and 7 was increased in a
dose-dependent fashion (P = 0.014 and P < 0.0001) up to 3.5-fold in the
exposed workers. These results demonstrate that leukemia-specific changes
in chromosomes 5 and 7 can be detected by FISH in the peripheral blood of
otherwise healthy benzene-exposed workers. We suggest that aberrations in
chromosomes 5 and 7 may be useful biomarkers of early biological effect for
benzene exposure.
相似文献
94.
Dietary factors and the risk of squamous cell esophageal cancer among black and white men in the United States 总被引:4,自引:0,他引:4
Linda Morris Brown Christine A. Swanson Gloria Gridley G. Marie Swanson Debra T. Silverman Raymond S. Greenberg Richard B. Hayes Janet B. Schoenberg Linda M. Pottern Ann G. Schwartz Jonathan M. Liff Robert Hoover Joseph F. Fraumeni 《Cancer causes & control : CCC》1998,9(5):467-474
Objectives: To investigate dietary factors for squamous cell esophageal cancer and whether these factors may contribute to the five-fold higher incidence of this cancer in the black versus white population of the United States.Methods: Data from a food frequency questionnaire were analyzed for 114 white men and 219 black men with squamous cell esophageal cancer, and 681 white and 557 black male controls from three areas of the United States who participated in a population-based case-control study of esophageal cancer.Results: Protective effects were associated with intake of raw fruits and vegetables (odds ratio for high versus low consumers=0.3 in both white and black men) and use of vitamin supplements (especially vitamin C; odds ratio for high versus low consumers=0.4 in both races), with the frequency of consumption of raw fruits and vegetables and vitamin supplements being greater for white than black controls. In addition, elevated risks were associated with high versus low intake of red meat (OR=2.7 for blacks and 1.5 for whites) and processed meat (OR=1.6 for blacks and 1.7 for whites), with the levels of consumption being greater for black than white controls.Conclusions: In the United States, these dietary factors may contribute in part to the much higher incidence of squamous cell esophageal cancer among black compared to white men. 相似文献
95.
OBJECTIVE. The objective was to determine the MR imaging findings that differentiate intact anterior cruciate ligament reconstruction graft, partial-thickness tear, and full-thickness tear, using arthroscopy as the gold standard. MATERIALS AND METHODS. Sixteen consecutive MR imaging examinations were retrospectively and independently evaluated by two musculoskeletal radiologists for primary signs (graft signal, orientation, fiber continuity, complete discontinuity, and thickness) and secondary signs (anterior tibial translation, uncovered posterior horn lateral meniscus, posterior cruciate ligament hyperbuckling, and abnormal posterior cruciate ligament line) of anterior cruciate ligament reconstruction graft tear in 15 patients with follow-up arthroscopy. Results were compared with arthroscopy, and both receiver operating characteristic curves and kappa values for interobserver variability were calculated. RESULTS. Arthroscopy revealed four full-thickness graft tears, seven partial-thickness tears, and five intact grafts. Of the primary signs, graft fiber continuity in the coronal plane and 100% graft thickness in the sagittal or coronal plane were most valuable in excluding full-thickness tear. Complete discontinuous graft in the coronal plane also was valuable in diagnosis of full-thickness tear. Of the secondary signs, anterior tibial translation and uncovered posterior horn lateral meniscus assisted in differentiating graft tear (partial or full thickness) from intact graft. The other primary and secondary signs were less valuable. Kappa values were highest for graft fiber continuity and graft discontinuity in the coronal plane. CONCLUSION. Full-thickness anterior cruciate ligament graft tear can be differentiated from partial-thickness tear or intact graft by evaluating for graft fiber continuity (coronal plane), complete graft discontinuity (coronal plane), and graft thickness (coronal or sagittal plane). 相似文献
96.
Hans-Peter Gschwind Ulrike Pfaar Felix Waldmeier Markus Zollinger Claudia Sayer Peter Zbinden Michael Hayes Rolf Pokorny Michael Seiberling Monique Ben-Am Bin Peng Gerhard Gross 《Drug metabolism and disposition》2005,33(10):1503-1512
Imatinib mesylate (GLEEVEC, GLIVEC, formerly STI571) has demonstrated unprecedented efficacy as first-line therapy for treatment for all phases of chronic myelogenous leukemia and metastatic and unresectable malignant gastrointestinal stromal tumors. Disposition and biotransformation of imatinib were studied in four male healthy volunteers after a single oral dose of 239 mg of (14)C-labeled imatinib mesylate. Biological fluids were analyzed for total radioactivity, imatinib, and its main metabolite CGP74588. Metabolite patterns were determined by radio-high-performance liquid chromatography with off-line microplate solid scintillation counting and characterized by liquid chromatography-mass spectrometry. Imatinib treatment was well tolerated without serious adverse events. Absorption was rapid (t(max) 1-2 h) and complete with imatinib as the major radioactive compound in plasma. Maximum plasma concentrations were 0.921 +/- 0.095 mug/ml (mean +/- S.D., n = 4) for imatinib and 0.115 +/- 0.026 mug/ml for the pharmacologically active N-desmethyl metabolite (CGP74588). Mean plasma terminal elimination half-lives were 13.5 +/- 0.9 h for imatinib, 20.6 +/- 1.7 h for CGP74588, and 57.3 +/- 12.5 h for (14)C radioactivity. Imatinib was predominantly cleared through oxidative metabolism. Approximately 65 and 9% of total systemic exposure [AUC(0-24 h) (area under the concentration time curve) of radioactivity] corresponded to imatinib and CGP74588, respectively. The remaining proportion corresponded mainly to oxidized derivatives of imatinib and CGP74588. Imatinib and its metabolites were excreted predominantly via the biliary-fecal route. Excretion of radioactivity was slow with a mean radiocarbon recovery of 80% within 7 days (67% in feces, 13% in urine). Approximately 28 and 13% of the dose in the excreta corresponded to imatinib and CGP74588, respectively. 相似文献
97.
Use of a reusable shielded marker to enhance the accuracy, safety, and efficacy of nuclear medicine procedures 总被引:1,自引:0,他引:1
Three cases illustrate the use of a reusable, shielded marker to identify anatomic structures and mark pathologic lesions. No other nuclear medicine marker is available with a shutter mechanism designed to interrupt radiation, thus protecting the patient and technologist from unnecessary radiation and minimizing image artifacts. 相似文献
98.
Michael P. Fitzgerald Adam Reynolds Cliona Mc Garvey Gary Norman Mary D. King Breda C. Hayes 《European journal of paediatric neurology》2019,23(1):81-86
Objective
To establish the local incidence of hearing loss in newborns with Hypoxic Ischaemic Encephalopathy (HIE) and to identify associated risk factors.Study design
Retrospective Cohort Study. Neonatal Intensive Care Unit (NICU) dual stage hearing screening protocol, including automated otoacoustic emissions (AOAE) and automated auditory brainstem response (AABR) testing.Results
57 newborns received therapeutic hypothermia for HIE. Twelve babies (21%) died. Audiology data was incomplete in 3 babies. Complete data was available for 42 babies (male n = 24), 4 (9.5%) of whom had hearing impairment. The development of hearing loss was associated with abnormal blood glucose levels (p = 0.006), low Apgar score at 1 min (p = 0.0219) and evidence of multi organ dysfunction [high creatinine (p = 0.0172 and 0.0198) and raised liver transaminases (aspartate aminotransferase (AST) p = 0.0012, alanine aminotransferase (ALT) p = 0.0037)]. An association with gentamicin was not found.Conclusion
This study confirms that hearing impairment is common in term infants who have undergone therapeutic hypothermia for moderate/severe HIE. Blood glucose should be monitored carefully in these infants and developmental surveillance should include formal audiology. Further larger studies are needed to clarify the role, if any, of hypothermia per se in causation of hearing loss and to fully identify risk factors for hearing impairment in this population.What is new
The current study confirms that hearing impairment is common in term infants who have undergone therapeutic hypothermia for moderate/severe HIE.No association between gentamicin use and the development of hearing impairment was found however initial blood glucose outside the normal range was of significance.Other factors associated with hearing impairment were low Apgar scores, greater need for resuscitation and evidence of multi organ dysfunction (renal and liver failure). 相似文献99.
Marielle E. Yohe Christine M. Heske Elizabeth Stewart Peter C. Adamson Nabil Ahmed Cristina R. Antonescu Eleanor Chen Natalie Collins Alan Ehrlich Rene L. Galindo Berkley E. Gryder Heidi Hahn Sharon Hammond Mark E. Hatley Douglas S. Hawkins Madeline N. Hayes Andrea Hayes‐Jordan Lee J. Helman Simone Hettmer Myron S. Ignatius Charles Keller Javed Khan David G. Kirsch Corinne M. Linardic Philip J. Lupo Rossella Rota Jack F. Shern Janet Shipley Sivasish Sindiri Stephen J. Tapscott Christopher R. Vakoc Leonard H. Wexler David M. Langenau 《Pediatric blood & cancer》2019,66(10)
Overall survival rates for pediatric patients with high‐risk or relapsed rhabdomyosarcoma (RMS) have not improved significantly since the 1980s. Recent studies have identified a number of targetable vulnerabilities in RMS, but these discoveries have infrequently translated into clinical trials. We propose streamlining the process by which agents are selected for clinical evaluation in RMS. We believe that strong consideration should be given to the development of combination therapies that add biologically targeted agents to conventional cytotoxic drugs. One example of this type of combination is the addition of the WEE1 inhibitor AZD1775 to the conventional cytotoxic chemotherapeutics, vincristine and irinotecan. 相似文献
100.