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991.
Human papillomavirus DNA in glandular dysplasia and microglandular hyperplasia: presumed precursors of adenocarcinoma of the uterine cervix 总被引:2,自引:0,他引:2
T Tase T Okagaki B A Clark L B Twiggs R S Ostrow A J Faras 《Obstetrics and gynecology》1989,73(6):1005-1008
Presumed precursors of adenocarcinoma of the uterine cervix were investigated with specific techniques to identify human papillomavirus (HPV) DNA. The presence of HPV DNA in 36 lesions of glandular dysplasia and 16 lesions of microglandular hyperplasia of the uterine cervix was studied by in situ hybridization using 3H-labeled HPV 16 and HPV 18 DNA probes. Only two of 36 lesions (6%) of glandular dysplasia contained HPV 18 DNA, although 64% of coexisting adenocarcinoma in situ, microinvasive adenocarcinoma, and cervical squamous intraepithelial neoplasia III lesions contained HPV 18 and/or HPV 16 DNA. Two lesions of HPV 18 DNA-positive glandular dysplasia coexisted with adenocarcinoma in situ that contained the same type of HPV DNA. None of the microglandular hyperplasia lesions contained HPV 16 DNA or HPV 18 DNA. These results suggest that, if HPV infection is an initial step toward carcinogenesis, it is unlikely that glandular dysplasia and microglandular hyperplasia are precursor lesions of adenocarcinoma of the uterine cervix. A large proportion of glandular dysplasia may represent reactive lesions of endocervical columnar epithelium. Two lesions of HPV 18 DNA-positive glandular dysplasia may represent well-differentiated components of adenocarcinoma in situ of the uterine cervix. 相似文献
992.
993.
It has been postulated that motion stimulation accelerates postnatal development. To test this hypothesis, 26 premature infants participated in a randomized controlled study of the effects of rocking on body weight gain and measures of neuromuscular development. Treatment infants were exposed to 15-min sessions of sinusoidal oscillation about the longitudinal axis, three times a day for 2 weeks. Infants were evaluated at the beginning and end of the 2-week treatment period and 2 weeks later. Neuromuscular development at these three times was measured with the comprehensive Dubowitz examination. Following treatment, large as compared with small premature infants showed a marked, but not statistically significant increase in weight gain. Duration of treatment appears to be a critical factor in influencing weight gain. All infants exposed to motion stimulation showed significant gains over controls in overall neuromuscular development. Passive muscle tone (posture, arm recoil and popliteal angle) and active motility (arm traction, head lag and ventral suspension) showed significant improvement in the treatment group at posttest. Similar results were recorded with auditory and visual orientation, alertness and defensive reaction. These specific areas of behavior have been recognized to be delayed in premature infants not exposed to a program of sensory stimulation. 相似文献
994.
From January 1, 1972 to December 31, 1981, sixty-five patients underwent pelvic exenteration as treatment for recurrent or persistent gynecologic malignancy at Memorial Sloan-Kettering Cancer Center. Cervical carcinoma was the disease most commonly treated by exenteration. The operative mortality of 9.2% represents an improvement over previous reports from this institution. After routine use of prophylactic minidose heparin, no cases of thrombophlebitis or pulmonary embolus occurred postoperatively. A 5-year survival rate of 23% warrants continued use of exenteration in carefully selected patients. The significant mortality and morbidity associated with pelvic exenteration preclude its use as a palliative procedure. 相似文献
995.
Ultrasonographic umbilical artery blood flow velocity waveform analysis has been proposed as a means of noninvasive assessment of fetal well-being. We computed waveform indices from directly measured umbilical artery blood flow in chronically instrumented ovine fetuses from 109 to 138 days of gestation (term, 145 days). The three waveform indices (systolic/diastolic ratio, pulsatility index, and resistance index) correlated significantly with each other (r = 0.90 to 0.98). These indices progressively decreased with gestation and were significantly correlated with calculated umbilical vascular resistance (r = 0.68 to 0.70, p less than 0.01) and with umbilical blood flow (r = -0.71, p less than 0.01). During the final week of pregnancy, systolic/diastolic ratio could be predicted by the combination of placental size (total cotyledonary mass), fetal size (ponderal index), and either umbilical blood flow or umbilical vascular resistance (multiple linear regression, r2 = 0.94). Fetal heart rate declined from day 109 of gestation to 138 days. Fetal heart rate was significantly correlated with waveform indices only when values exceeded 170 beats/min (r = -0.37 to -0.51). Ovine fetal umbilical artery waveform indices changed at approximately the same rate as those reported for human fetuses in late gestation on the basis of external Doppler ultrasonographic velocity measurements. These results suggest that the sheep is a suitable model for investigations of umbilical artery waveform analysis. 相似文献
996.
BACKGROUND: This paper examines whether the Massachusetts Tobacco Control Program is affecting the rates of smoking and smokeless tobacco use among Massachusetts' youth. METHODS: School survey data from the Massachusetts Prevalence Study were analyzed to estimate differences between 1993 and 1996 rates of youth cigarette and smokeless tobacco use, attitudes toward smoking, and awareness of cigarette ads and promotions of antismoking messages. RESULTS: Lifetime and Current Smoking rates declined significantly among middle school males, contrasting with stable national trends. Among girls in this age group, Lifetime and Current Smoking did not change significantly. Hispanic middle school students exhibited a significant decline in Lifetime Use. There were no significant changes in Lifetime or Current Smoking rates among high school students. Lifetime use of smokeless tobacco declined among middle school students while Current Use declined among both middle and high school students. Students reported declines in awareness of cigarette ads or promotions and increases in awareness of antismoking messages. CONCLUSIONS: These results provide evidence for cautious optimism regarding the impact of tobacco control, but indicate that these efforts should begin earlier and that additional research is needed to understand and address the problems of tobacco use by girls. 相似文献
997.
The purpose of a respirator is to prevent the inhalation of harmful airborne substances or to provide a source of respirable air when breathing in oxygen-deficient atmospheres. For a physician to recommend the use of respirator, general background information on respiratory-protective devices is required. The first part of this clinical practice review describes the general aspects of industrial hygiene, respirators and a respirator-certification program. The second part addresses matters related to medical certification for respirator use. Medical certification for respirators is an important part of the activities of the occupational physician. To determine whether a worker is able to tolerate the added strain of a respiratory protective device is a complex process in which factors such as fitness for work, health of the individual, characteristics of the work itself, and the properties, type, and requirements of the respiratory protective device, have to be considered. Medical certification is of utmost importance for respirator use, and it should be viewed as an element in a comprehensive respiratory protection program. A comprehensive program is the key element in affording the workers' effective respiratory protection once the initial steps of the hierarchy of methods of hazard control have proved insufficient or infeasible. As a result, the need for the industrial hygiene/safety officer, the worker, the employer and the medical professional to work as a team is much more than in any other field of occupational medicine--a necessary requirement for making the right decision. 相似文献
998.
A case is presented in which apparent non-mosaic trisomy 16 was found in chorionic villi (direct and culture) obtained from a patient undergoing first-trimester prenatal diagnosis. The fetal karyotype subsequently was determined to be 46,XX by follow-up amniocentesis. Serial ultrasonographic examinations revealed placental sonolucencies and intrauterine growth retardation. At 37 weeks, a small-for-gestational-age female was delivered by Caesarean section for fetal distress. Postnatal cytogenetic studies revealed a normal female karyotype in cord blood and mosaic trisomy 16 in placental tissues. These findings suggest that in cases where aneuploidy is confined to placental tissues, it may have biological significance, as evidenced by the apparent placental dysfunction and poor fetal growth in this case. 相似文献
999.
A workshop for 18 doctors and managers at the start of their careers revealed considerable differences of opinion about the roles of the two groups. Managers were more firmly convinced than doctors that their role in hospitals was indispensable. Doctors saw managers as being in the pockets of politicians. The workshop did not change doctors' views. 相似文献
1000.