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91.
92.
R L Hansen A T Evans K M Gillogley C S Hughes P G Krener 《Journal of perinatology》1992,12(3):220-224
Accurate identification of substance abusing mothers and their infants is critical for appropriate medical management as well as the collection of accurate information on the effects of illicit drug use on perinatal morbidity, mortality, and long-term neurobehavioral outcome in the infants. This study examines the differences found using two methods for urine toxicology screening at the time of obstetrical admission to the hospital. The institution of universal screening identified significantly more women than were previously identified through the use of a risk-directed protocol (P less than .0001). Women identified using either protocol were significantly more likely than toxicology-negative women to have had poor prenatal care and to have smoked and used alcohol during pregnancy (P less than .001). In the population studied, the multiple criteria needed to accurately identify mothers with positive-toxicology screens would also include screening over one half of the toxicology-negative mothers. 相似文献
93.
D. A. Basketter E. W. Scholes M. Cumberbatch C. D. Evans I. Kimber 《Contact dermatitis》1992,27(4):209-213
The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man. 相似文献
94.
95.
Abnormalities of copper in Gilles de la Tourette syndrome 总被引:1,自引:0,他引:1
The Gilles de la Tourette syndrome is a disorder whose etiology and pathogenesis are little understood. The number of biochemical abnormalities described in this disorder is minimal. Ten of a total of 80 patients were found to have an abnormally low serum copper. A report is presented on two patients who consented to further detailed investigation and in whom copper radioisotope studies were carried out. Both exhibited abnormalities of copper handling, in that we observed an abnormally fast disappearance of copper from the plasma and an abnormally slow uptake by the liver. The rates of intestinal absorption and urinary excretion were normal. We did not identify an abnormal site of sequestration of the metal in the body. 相似文献
96.
S E Evans J S Crawford I D Stevens G M Durbin H Daya 《British journal of obstetrics and gynaecology》1986,93(4):329-333
Two types of fluid regimen were provided for patients having labour induced under epidural analgesia. Reasons for the infusion were to pre-load the circulation before the epidural, and subsequently to sustain maternal hydration. Both fluids were isotonic, one was predominantly saline based (Hartmann's solution) and the other contained both saline and dextrose. Blood glucose and serum sodium, lactate and beta-hydroxybutyrate were measured before the start of induction, at delivery and in the cord sample. Blood glucose and serum sodium were measured in the babies at 12 and 24 h of age. The dextrose-saline fluid caused small but significant changes in blood glucose and serum sodium which did not exceed the normal reference limits for either. The use of Hartmann's solution was associated with considerable rises in maternal serum beta-hydroxybutyrate at delivery. Neither fluid had any significant effect on the blood glucose or serum sodium in infants at 12 and 24 h of age. 相似文献
97.
We present the findings of a pilot study to assess the perception of risk in 155 women with a family history of breast cancer by questionnaire. Only 11% of women were able to identify the correct population risk and more than half were unable to assess their own lifetime risk within 50% of the clinicians'' estimate. Although it is probable that women are helped by genetic counselling and if at substantial risk, annual mammography, the psychological impact of assigning true risk and the value of mammography need to be evaluated. 相似文献
98.
In conscious rabbits an inferior vena caval cuff was progressively inflated so cardiac output fell at a constant approximately 8% of its baseline value. There was a biphasic haemodynamic response, consisting of an initial compensatory phase during which there was progressive systemic vasoconstriction and tachycardia, followed by a decompensatory phase in which systemic vasoconstriction failed abruptly, blood pressure plummeted and heart rate declined. We tested the effects on the haemodynamic response of prior 4th ventricular, and in some cases intravenous, infusions of saline, yohimbine, clonidine, yohimbine plus clonidine, and bunazosin. From the results we conclude that a yohimbine-sensitive mechanism in the brainstem, possibly alpha 2-adrenoceptor-mediated, may be an essential element of the cardiac receptor-mediated decompensatory phase of acute central hypovolaemia, but does not contribute to the arterial baroreflex-mediated compensatory phase. 相似文献
99.
Estimation of body composition in Chinese and British men by ultrasonographic assessment of segmental adipose tissue volume. 总被引:1,自引:1,他引:0 下载免费PDF全文
It has been shown that ultrasonographic measurements can be used to predict body composition in adults. The purpose of this study was to assess the relationship between ultrasonograph and caliper (SKF) measurements of subcutaneous adipose tissue thickness in athletic Caucasian (English, E) and Asian (Chinese, C) men against estimates of body composition determined from hydrodensitometry (HYD). The usefulness of a proposed ultrasonographic method of estimating lean and fat proportions in the upper and lower limbs was also evaluated as a potential method of predicting body composition. Ultrasonography (US) was used to measure adipose and skin thickness at the following sites: biceps, triceps, subscapular, suprailiac, abdominal, pectoral, thigh and calf. Caliper measurements were also made at the above sites. Subcutaneous fat thickness and segmental radius were measured directly from the display screen of the ultrasonic scanner (Aloka 500 SD). By applying the geometry of a cone, the proximal and distal radii of the upper arm and upper leg were used to calculate the proportionate volumes of adipose tissue. The best correlations for US and SKF were obtained at the quadriceps, subscapular and pectoral sites for E (r = 0.96, 0.93 and 0.90, respectively) and at the quadriceps, calf and abdominal sites for C (r = 0.90, 0.81 and 0.75, respectively). The best ultrasonographic predictor of the percentage fat in both groups was the percentage adipose tissue volume in the upper leg (r = 0.83 and 0.79 for C and E, respectively). Stepwise multiple regression analysis indicated that the prediction of percentage fat was improved by the addition of the ultrasonographic abdomen measurement in both groups: Chinese sample: %fat = %fat(leg) (0.491) + US abdomen (0.337) + 0.95 ( R = 0.89, s.e.e. = 1.9%); English sample: %fat = %fat(leg) (0.435) + US abdomen (0.230) - 0.765 ( R = 0.80, s.e.e. = 3.6%). It is concluded that ultrasonographic measurements of subcutaneous adipose tissue and volumetric assessment of percentage adipose tissue in the thigh are useful estimates of body composition in athletic English and Chinese males. 相似文献
100.