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81.
Cheung R Tucker SL Dong L Kuban D 《International journal of radiation oncology, biology, physics》2003,56(5):1234-1240
INTRODUCTION: The literature on dose-response characteristics of high-risk prostate cancer has been scarce in this era, when these patients are treated with hormone therapy along with radiotherapy. In this study, we estimated the dose-response of prostate-specific antigen (PSA) control probability in high-risk prostate cancer patients treated with radiotherapy alone. METHODS AND MATERIALS: The data set contains information on 363 high-risk prostate cancer patients who were treated with external beam radiotherapy without hormonal treatment between February 1987 and September 1998. These patients have one or more of the following adverse prognostic features: digital rectal examination stage > or =cT3, PSA >20 ng/mL, and biopsy Gleason score > or =8. These patients had biopsy-proven adenocarcinoma of prostate and were staged according to the 1992 AJCC staging system that was based on digital rectal examination. The logistic model was fitted to the data at various time points after treatment, and the dose-response parameters were estimated. RESULTS: The dose required to have 50% tumor control, TCD50 (95% confidence interval), for high-risk patients is 75.5 (range: 70.7-80.2) Gy. The gamma 50 (95% confidence interval) is 1.7 (range: 0.7-2.7) around 75.5 Gy. Recursive partitioning analysis based on the null Martingale residuals identifies two subgroups within the high-risk group. The TCD50 estimates of the two subgroups (PSA < or = vs. >20 ng/mL) differ by 15 Gy at 5 years. There is a dose response in both subgroups. CONCLUSION: We recognize that this study has the usual limitations of a retrospective study that includes treatment policy change that spanned a long time frame. However, our data strongly suggest a benefit of dose escalation for all the patients in the entire high-risk group. There is a steep dose response in PSA control probability around a modern dose of 78 Gy. A 5-Gy dose increase beyond 78 Gy may improve PSA control by about 10%. 相似文献
82.
Thames H Kuban D Levy L Horwitz EM Kupelian P Martinez A Michalski J Pisansky T Sandler H Shipley W Zelefsky M Zietman A 《International journal of radiation oncology, biology, physics》2003,57(4):929-943
PURPOSE: To assess the merit of the American Society for Therapeutic Radiology and Oncology (ASTRO) definition of biochemical failure after external beam radiotherapy for prostate cancer by testing alternative prostate-specific antigen (PSA) failure definitions against the "gold standard" of clinical failure and to study the effect of backdating the time of failure. METHODS AND MATERIALS: Nine participating institutions agreed to submit follow-up results for all patients with clinically localized prostatic cancer (Stage T1b, T1c, T2, N0M0) treated between 1986 and 1995 by external beam radiotherapy only, to doses of >or=60 Gy, with no androgen deprivation before treatment. A total of 4839 men met the study criteria, with a median follow-up time of 6.3 years. The prediction of clinical failure by 102 definitions of biochemical failure was assessed using various quantitative measures. RESULTS: Four definitions were superior as measured by the sensitivity, specificity, positive and negative predictive values, and hazard of clinical failure after biochemical failure: two rises of at least 0.5 ng/mL backdated, PSA level at or greater than the absolute nadir plus 2 ng/mL at the call date, and PSA level at or greater than the current nadir plus 2 or 3 ng/mL at the call date. The absolute nadir was the lowest measured PSA level during all of follow-up, and the current nadir was the lowest PSA measured previous to a particular PSA measurement during follow-up. With the possible exception of patients in the low-risk group, the likelihood of ultimate clinical failure decreased as the time of biochemical failure increased. Failure definitions based on PSA levels >0.2 or 0.5 ng/mL were inferior to other definitions. Backdating the failure time introduced bias into the estimate of freedom from biochemical failure, which was increasingly overestimated at shorter median follow-up times. This bias can be circumvented either by using a failure definition based on the call date or by backdating the censoring times of patients with one or two rises who could potentially have failure at a future (unobserved) time. A short follow-up time as such does not result in bias unless the failures are backdated; in the absence of backdating, it is the precision of failure-free survival that is increasingly compromised as the follow-up time is reduced. CONCLUSION: The ASTRO failure definition ended the confusion resulting from different failure definitions that had been in use, and it did so accurately enough that it is probably not necessary to recalculate previously published results. Nevertheless, for the current pooled analysis of outcome in 4839 men with a 6.3-year median follow-up, other definitions of biochemical failure were superior as assessed by various quantitative measures of concordance of biochemical and ultimate clinical failure. An additional disadvantage of the ASTRO definition is the bias introduced by backdating failures, as well as the necessarily retrospective nature of its application. Some "current" definitions, but not those based on the PSA level rising above a fixed threshold, have significantly higher sensitivity and specificity, do not lead to biased estimations of biochemical disease-free survival, and are directly applicable during patient counseling. These are all issues that would play a role in replacing the ASTRO consensus definition. 相似文献
83.
Blanchard R Kuban ME Klassen P Dickey R Christensen BK Cantor JM Blak T 《Archives of sexual behavior》2003,32(6):573-581
Previous research has found that pedophilic men referred for clinical assessment of their sexual behavior are more likely to report that they suffered head injuries before their 13th birthday than are nonpedophilic men referred for the same purpose. This study investigated whether pedophilic patients are also more likely to report head injuries after their 13th birthday. The 685 participants represented all patients with usable data from a consecutive series of men referred to a clinical laboratory specializing in phallometric assessment of erotic preferences. In addition to phallometric testing, participants were administered a brief neuropsychological test battery and a companion interview, which included questions on head injury, drug abuse, and childhood diagnosis of attention-deficit/hyperactivity disorder. The results showed that the pedophilic patients reported more head injuries before age 13 than did the nonpedophilic patients, but they did not report more head injuries after age 13. The association between pedophilia and childhood head injuries could mean either that subtle brain damage after birth increases a boy's risk of pedophilia, or that neurodevelopmental problems before birth increase a boy's accident-proneness along with his risk of pedophilia. Additional analyses showed that self-reported head injuries before age 13 were associated with attentional problems and with left-handedness; in contrast, head injuries after age 13 were associated with drug abuse and promiscuity. These analyses suggest that, among patients with primary presenting complaints of sexual rather than cognitive problems, childhood head injuries cluster with neuropsychological phenomena, whereas later head injuries cluster with lifestyle variables. 相似文献
84.
Casanueva FF Molitch ME Schlechte JA Abs R Bonert V Bronstein MD Brue T Cappabianca P Colao A Fahlbusch R Fideleff H Hadani M Kelly P Kleinberg D Laws ED Marek J Scanlon M Sobrinho LG Wass JAH Giustina A 吴哲褒 张亚卓 《中华神经外科杂志》2008,24(8)
3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异. 相似文献
85.
Ten classic deep tendon reflexes (DTRs) were evaluated in 62 premature infants of greater than 27 weeks post-conceptional age. The pectoralis major was the most readily elicitable reflex in all infants (100%), regardless of maturity. Achilles, patellar, biceps, thigh adductors, and brachioradialis reflexes also were obtained in at least 98% of babies of greater than 33 weeks gestation. Among these reflexes, less mature infants (less than 33 weeks gestation) had decreased elicitation rates for patellar and biceps reflexes and overall had diminished reflex intensity when compared to older infants (33-36 weeks gestation). By order of decreasing rate, finger flexors, jaw, crossed adductors, and triceps reflexes were less frequently elicited in both groups. Equal DTRs were obtained often in healthy and previously ill infants of less than 33 weeks gestation. Head position had no apparent affect on the ability to elicit reflexes. Theophylline therapy tended to intensify the Achilles reflex and the quiet, wakeful state appeared to be the most optimal state for the elicitation of DTRs. 相似文献
86.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献
87.
Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function. 相似文献
88.
We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia. 相似文献
89.
Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases 总被引:1,自引:0,他引:1
Bernardino ME; Erwin BC; Steinberg HV; Baumgartner BR; Torres WE; Gedgaudas- McClees RK 《Radiology》1986,159(1):71-74
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary. 相似文献
90.
V. de las Alas MD W. D. Voorhees PhD L. A. Geddes ME PhD J. D. Bourland PhD W. E. Schoenlein 《Journal of clinical monitoring and computing》1990,6(3):183-185
In 4 spontaneously breathing, barbiturate-anesthetized dogs, hyperthermia was induced with 2,4-dinitrophenol while rectal
temperature, heart rate, mean blood pressure, end-tidal carbon dioxide, and carbon dioxide production (milliliters per minute)
were measured continuously. The latter was determined with a pneumotachygraph (to obtain respired volume) and an infrared
carbon dioxide analyzer that measured inspired and expired carbon dioxide concentration. Of the five physiologic measurements,
the increase in carbon dioxide production preceded the increase in rectal temperature by more than 120 seconds. End-tidal
carbon dioxide was an unreliable indicator in the spontaneously breathing animal of approaching hyperthermia during spontaneous
breathing due to a transient tachypnea, which decreased end-tidal carbon dioxide. The carbon dioxide production (milliliters
per minute) increased immediately and reached three to five times the control value. Blood pressure and heart rate were insensitive
indicators of approaching hyperthermia. 相似文献