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Suprascapular nerve injuries at the spinoglenoid notch are uncommon. The true incidence of this lesion is unknown; however, it appears to be more common in athletes who participate in sports involving overhead activities. When a patient is being evaluated for posterior shoulder pain and infraspinatus muscle weakness, electrodiagnostic studies are an essential part of the evaluation. Electromyography will identify an injury to the suprascapular nerve as well as assist in localizing the site of injury. In addition, imaging studies are also indicated to help exclude other diagnoses that can mimic a suprascapular nerve injury. The initial management should consist of cessation of the aggravating activity along with an organized shoulder rehabilitation program. If the patient fails to improve with 6 months to 1 year of nonoperative management, surgical exploration of the suprascapular nerve should be considered. Release of the spinoglenoid ligament with resultant suprascapular nerve decompression may result in relief of pain and a return of normal shoulder function. 相似文献
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Cummins RJ Mothersill C Seymour CB Johns H Joiner MC 《International journal of radiation biology》1999,75(2):225-232
PURPOSE: To investigate the effect of irradiating microcolonies of various sizes on their subsequent ability to form colonies. MATERIALS AND METHODS: The location of individual HPV-G cells in tissue culture flasks was recorded using computerized microscopy. This allowed the cells' positions to be continually revisited, which enabled manual sizing of individual microcolonies both at the time of irradiation (between 0-5 Gy) and following an incubation period during which the microcolonies were assessed for cologenic survival. RESULTS: The experiments indicate that when irradiated as microcolonies, cells have plating efficiencies (PE) that are lower than expected when compared with the prediction from the PE values of cells irradiated individually. CONCLUSION: These data support the conclusions of Mothersill and Seymour (1997b) which challenge the concept of independent survival of certain types of cells following irradiation. The results indicate that interactions between cells can occur even in small aggregates. 相似文献
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Studies of diabetic polyneuropathy using conduction velocity distribution (DCV) analysis 总被引:5,自引:0,他引:5
L J Dorfman K L Cummins G M Reaven J Ceranski M S Greenfield L Doberne 《Neurology》1983,33(6):773-779
The distributions of nerve fiber conduction velocities (DCVs) derived from the median nerves of 29 adult diabetic patients (mean age, 52.1 +/- 12.3 years) with mild or no symptoms or signs of polyneuropathy were compared with DCVs from 34 age-appropriate normal subjects. Ten patients (34%) had normal findings (type A DCVs). In the 19 patients (66%) with abnormal DCVs, defined as 10% or more of the DCV area falling outside the normal 95% confidence limits, two distinct patterns of DCV alteration were observed: type B DCVs (11 patients) showed reduced DCVmax, DCVmean, and DCVpeak, together with reduced DCVrange (narrow profile); whereas type C DCVs (8 patients) had reduced DCVmax, DCVmean, DCVpeak, and DCVmin, with normal DCVrange (broad profile). It is proposed that type C DCV represents a more advanced form of type B and that both reflect selective dysfunction of the fastest conducting (presumably largest-diameter) fibers in the nerve trunk. DCVmax was consistently greater than conventional measures of "maximal" CV in all patient subgroups. Patients with abnormal DCVs had higher incidence of mild neuropathic symptoms (15 of 19 versus 4 of 10, p less than 0.01) and greater insulin dependence (11 of 19 versus 1 of 10, p less than 0.001). Serial studies in 10 patients showed, at most, small degrees of change in conduction properties over relatively short intervals (1 to 9 months). 相似文献
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A randomized controlled study of luteal support therapy (using intramuscular injections of progesterone and/or human chorionic gonadotropin) was conducted in a trial designed to minimize variables that might adversely affect the change of pregnancy. After applying rigid selection criteria, 207 women were recruited into one of four groups. Mathematical modeling was applied to the results to determine if there were degrees of improvement in uterine receptivity relative to various grades of embryo quality ("E" factor). Although the trial size was insufficient to enable the detection of significant improvements in the pregnancy rates that ranged from 27.5% for non-treatment to 41.2% for those receiving combined treatment, the birth rates were significantly better with luteal support (11.8% versus 29.4%). Similarly, the overall implantation rate just failed to reach statistical significance for luteal support, but the ongoing implantations were significantly better (3.6% versus 9.0%). Data modeling indicated that luteal support, particularly with the combined regimen, could improve the ongoing implantation rate by up to 2.5-fold when the E factor was poorest. 相似文献
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OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease. 相似文献
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Context Health plan utilization review rules are intended to enforce insurance contracts and can alter and constrain the services that physicians provide to their patients. Physicians can manipulate these rules, but how often they do so is unknown. Objective To determine the frequency with which physicians manipulate reimbursement rules to obtain coverage for services they perceive as necessary, and the physician attitudes and personal and practice characteristics associated with these manipulations. Design, Setting, and Participants A random national sample of 1124 practicing physicians was surveyed by mail in 1998; the response rate was 64% (n = 720). Main Outcome Measure Use of 3 different tactics "sometimes" or more often in the last year: (1) exaggerating the severity of patients' conditions; (2) changing patients' billing diagnoses; and/or (3) reporting signs or symptoms that patients did not have to help the patients secure coverage for needed care. Results Thirty-nine percent of physicians reported using at least 1 tactic "sometimes" or more often in the last year. In multivariate models comparing these physicians with physicians who "never" or "rarely" used any of these tactics, physicians using these tactics were more likely to (1) believe that "gaming the system" is necessary to provide high-quality care today (odds ratio [OR], 3.67; 95% confidence interval [CI], 2.54-5.29); (2) have received requests from patients to deceive insurers (OR, 2.44; 95% CI, 1.72-3.45); (3) feel pressed for time during patient visits (OR, 1.69; 95% CI, 1.21-2.37); and (4) have more than 25% of their patients covered by Medicaid (OR, 1.60; 95% CI, 1.08-2.38). Notably, greater worry about prosecution for fraud did not affect physicians' use of these tactics (P = .34). Of those reporting using these tactics, 54% reported doing so more often now than 5 years ago. Conclusions A sizable minority of physicians report manipulating reimbursement rules so patients can receive care that physicians perceive is necessary. Unless novel strategies are developed to address this, greater utilization restrictions in the health care system are likely to increase physicians' use of such manipulative "covert advocacy" tactics. 相似文献