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31.
Bioactive stilbenes of Scirpus maritimus 总被引:1,自引:0,他引:1
32.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
33.
M F Powell 《Journal of pharmaceutical sciences》1986,75(9):901-903
In the absence of strong buffer catalysts, the degradation of codeine sulfate (7,8-didehydro-4,5 alpha-epoxy-3-methoxy-17-methylmorphinan-6 alpha-ol sulfate) in aqueous solution is described by the expression kobs = kH+ [H+] + k0 + kHO-[HO-], where kH+ = (3.9 +/- 1.3) X 10(-8) M-1 X S-1, k0 = (2.7 +/- 0.5) X 10(-8) S-1, and kHO- = (5.1 +/- 1.0) X 10(-6) M-1 X S-1 at 80 degrees C. The activation energies associated with these rate constants are 27.7, 21.0, and 28.3 kcal X mol-1, respectively. In the absence of buffer catalysis, codeine sulfate is predicted to have a room temperature shelf life of approximately 44 years between pH 1 and 10, significantly longer than the 1.1 year shelf life of codeine phosphate reported earlier. 相似文献
34.
This study focuses on the injury rates for natural grass and AstroTurf surfaces and the risk factors of game position and type of play. We examined the game-related knee sprains, medial collateral ligament sprains, and anterior cruciate ligament sprains that occurred in the National Football League during the 1980 to 1989 seasons. The findings are controlled for categories of severity (number of games missed due to injury), position, and situation (rushing or passing) at the time of injury. The analysis of the data incorporates epidemiologic techniques associated with incidence density ratios. The data show that there is a statistically significant difference between the higher AstroTurf injury rates for knee sprains. When knee sprains are separated into medial collateral ligament sprains and anterior cruciate ligament sprains, only the anterior cruciate ligament sprains show a statistically significant higher injury rate for AstroTurf. When simultaneous control variables are considered, significantly more knee sprains occurred to backs on rushing plays and linemen on passing plays. When controlling the data for severity, only the Category II injuries (three or more games missed) sustained by linemen on passing plays had statistically significant higher injury rates for the AstroTurf. For medial collateral ligament sprains, only the Category II injuries for linemen on passing plays remain statistically significant. The data for the ACL sprains show statistically significant differences between the injury rate on natural grass and the injury rate on Astro Turf under conditions of special teams play. 相似文献
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37.
Epidemiology and laboratory diagnosis of infection with viral and bacterial pathogens in infants hospitalized for suspected sepsis 总被引:1,自引:0,他引:1
A prospective study was conducted to determine the frequency and distribution of bacterial and viral pathogens in infants hospitalized with suspected sepsis and to evaluate the potential of virus detection for improving patient management. A causative organism was detected in 157 (67%) of 233 previously healthy infants less than 3 months of age, who had been hospitalized for suspected sepsis: 19 (8%) had bacterial infections, 135 (58%) had viral infections, and 3 (1%) had mixed viral-bacterial infections. Viral infections occurred in a seasonal pattern: enteroviruses were responsible for most of the hospitalizations during summer and fall (65/110; 63%) and respiratory syncytial and influenza A viruses were responsible for most of the infections during winter (44/81; 55%). In contrast, bacterial infections were not seasonally distributed. Virus was detected in 33% of the 138 infected infants within 24 hours, and in 64% within 3 days. We conclude that viral infections are prevalent among infants hospitalized for suspected sepsis, and most can be detected early enough to influence patient management. 相似文献
38.
Nancy D. Brener Etienne G. Krug Linda L. Dahlberg Kenneth E. Powell 《The Journal of school health》1997,67(5):171-174
ABSTRACT: Programs for preventing violence among youth should be evaluated to determine if they are effective. Nurses' logs appear to be a useful tool for evaluating school-based violence prevention programs. The logs provide a record of students' visits to the school nurse that can be used to determine if a violence prevention program is associated with a reduction in fighting—and other injury-related nurse visits. This method has many strengths: it is simple and inexpensive, it does not interrupt the school routine, it permits school-level rather than student-level data collection, it provides a ready "baseline," and it allows continuous data collection. However, potential limitations do exist. For example, the method may provide insufficient information and may be affected by factors unrelated to the intervention. School officials can increase the usefulness of the logs by encouraging standardization and providing training in their use. 相似文献
39.
Deferred treatment for prostate cancer 总被引:2,自引:0,他引:2
The clinical outcome of 278 prostate cancer patients managed by a deferred treatment policy was analysed retrospectively. Following TURP or biopsy, all patients were asymptomatic and deemed suitable for management by a deferred treatment policy, i.e. hormone therapy or other forms of treatment were only initiated if and when symptomatic progression occurred. The overall 5-year survival rate was 30%; 18% of patients died from other causes without needing treatment for their prostate cancer; 11% were alive and untreated after 5 years' follow-up; 17% died from prostate cancer without further treatment. Poor tumour grade, anaemia, metastatic disease, a short history, presentation with retention, and a raised serum creatinine at presentation were associated with a poor prognosis. 相似文献
40.
The pattern of cancer in white and Asian (Indian, Pakistani, and Bangladeshi) children living in the West Midlands Health Authority Region was investigated using age standardised incidence rates. Two sets of rates were calculated, a 10 year rate (1982-91) using survey based estimates of the ethnic population and a four year rate (1989-92) using the ethnic population counts from the 1991 census. The 10 year rates showed a significantly higher annual incidence of cancer in Asian (159.1/million/year) than in white (130.8) children. The pattern of cancers in Asian children was different, with an excess of lymphomas and germ cell tumours, and a deficit of rhabdomyosarcomas. These findings were confirmed by the four year rates. Although underestimation of the Asian population probably contributes to the apparent excess, there remains cause for concern that UK Asian children may be at higher risk of cancer. Accurate ethnic population figures and confirmatory studies are urgently required. 相似文献