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71.
AIM: To evaluate the retention of skills 6 months after training in ventilation and chest compressions (CPR) on a manikin with computer based on-line voice advisory feedback and the possible effects of initial overtraining. METHODS: Thirty five volunteers had 20 min provisional CPR training on a manikin with computer based voice advisory feedback but without an instructor. The appropriate feedback was taken from a pre-recorded list depending on performance measured by the manikin--computer system versus set limits for ventilation and compression variables. One group in addition was randomised to receive 10 similar 3 min training sessions during 1 week in the following month (overtrained group). All ventilation and compression variables were measured without feedback before and after the initial training session, with feedback immediately thereafter, and both without and with feedback 6 months after the initial training session. RESULTS: The initial training improved all variables. Compressions with correct depth increased from a mean of 33 to 77%, and correct inflations from a mean of 9 to 58%. After 6 months, the results for the controls were not significantly different from pre-training, except for a higher of correct inflations (18%), while the overtrained group had better retention of skills including the correct compression depth (mean 61%) and inflations (mean 42%). When verbal feedback was added both the compressions and ventilations immediately improved both when tested immediately and 6 months after the initial training session. CONCLUSIONS: The computer-based voice advisory manikin (VAM) feedback system can improve immediate performance of basic life support (BLS) skills, with better long-term retention with overtraining. 相似文献
72.
Vestergaard EM Poulsen SS Grønbaek H Larsen R Nielsen AM Ejskjaer K Clausen JT Thim L Nexø E 《Clinical chemistry》2002,48(10):1689-1695
BACKGROUND: The three trefoil factors (TFF1, TFF2, and TFF3) are small peptides believed to cross-link mucous glycoproteins and to play a role in the maintenance and repair of the gastrointestinal mucosa. To define the physiologic and potential diagnostic values of TFF3, assays able to measure TFF3 are warranted. METHODS: An ELISA was developed that uses two antibodies from rabbits immunized with recombinant human TFF3 and a calibrator (3-100 pmol/L) prepared from recombinant human TFF3. RESULTS: The ELISA had a detection limit of 3.0 pmol/L. The imprecision (CV) was 5-9% for mean concentrations of 13-65 pmol/L, corresponding to serum concentrations of 65-330 pmol/L. There was no cross-reaction toward human TFF1 and TFF2 (40 nmol/L). Neither food intake nor the menstrual cycle influenced the values of TFF3 significantly. The central 95% reference interval for TFF3 in serum from healthy blood donors (n = 300) was 91-250 pmol/L and showed no variation with age and limited variation with sex. TFF3 was increased in serum from patients (n = 12) with inflammation and/or ulceration of the upper gastrointestinal tract (P <0.05), whereas in serial measurements of serum from three patients with severe exacerbation of chronic inflammatory bowel disease restricted to the colon, normal concentrations and only minor variations during treatment and tapering were observed. CONCLUSIONS: The ELISA measures TFF3 in human serum and represents a specific and precise method for measurement of TFF3, which will be of value for further studies of TFF3 in health and disease. 相似文献
73.
Svaneborg N Kristensen SD Hansen LM Büllow I Husted SE Schmidt EB 《Thrombosis research》2002,105(4):311-316
Antiplatelet therapy with acetylsalicylic acid (ASA) is commonly used to reduce the risk of cardio- and cerebrovascular events. Fish consumption has been inversely related to coronary disease, which has been partly attributed to an inhibitory effect of n-3 polyunsaturated fatty acids (n-3 PUFA) on platelet production of tromboxane A2. In this study, we investigated the acute and short-time effect of supplementation with n-3 PUFA and intravenous ASA on platelet function, platelet fatty acid composition and plasma lipids. Eighteen healthy men were randomly allocated to a daily intake of 10 g n-3 PUFA or placebo. After this supplement (14 h and 14 days), blood was sampled before and after intravenous injection of 100 mg ASA. n-3 PUFA given for 14 days caused a minor inhibition of platelet reactivity but negligible compared to 100 mg ASA. No additive effect of n-3 PUFA and ASA could be demonstrated. 相似文献
74.
Benign solitary solid cold thyroid nodules: US-guided interstitial laser photocoagulation--initial experience 总被引:8,自引:0,他引:8
PURPOSE: To evaluate the effects of ultrasonography (US)-guided interstitial laser photocoagulation (ILP) on the volume of benign solitary solid cold thyroid nodules and any nodule-related symptoms. MATERIALS AND METHODS: ILP was performed in 16 patients with normal thyroid function and a solid benign thyroid nodule. None of the patients had uptake on a radionuclide scan. Patients underwent one ILP session. A needle was positioned in the thyroid nodule with US guidance, and the laser fiber was placed in the lumen of the needle. Patients were treated for 287-1,200 seconds with an output power of 1-3 W. ILP was performed with continuous US guidance and terminated when the echogenic changes were stationary. Thyroid nodule volume and thyroid function were evaluated before and 1, 3, and 6 months after treatment. During the same period, 15 untreated patients (control group) were followed up to evaluate the size of the untreated thyroid nodule. RESULTS: In the 16 patients treated with ILP, the mean thyroid nodule volume decreased from 10 to 5.4 mL (P <.001) after 6 months. The median energy given was 761 J. There was no relationship between the dose of thermal energy given and nodule reduction. Pressure symptoms were significantly reduced (P =.0002) after 6 months. The treatment was well-tolerated in all patients. No significant change in thyroid nodule volume was seen in the control group. CONCLUSION: US-guided ILP could become a useful nonsurgical alternative in the treatment of the benign solitary solid cold thyroid nodule in patients who cannot or will not undergo surgery. 相似文献
75.
Marianne Thoresen Kirsti Haaland Petter Andreas Steen 《Archives of disease in childhood. Fetal and neonatal edition》1994,71(2):F103-F106
To determine whether cerebral blood flow velocity (CBFV) measurements were representative of cerebral blood flow (CBF) changes in pathological flow situations five newborn piglets were investigated. They underwent measurements of CBF by electromagnetic flowmetry on a modified common carotid artery where extracerebral branches were tied off simultaneously with Doppler recording either from the same precerebral or an intracerebral artery. The two methods agreed well within moderate carbon dioxide and blood pressure changes. During severe hypotension and hypertension Doppler overestimated CBF by 25-100%. During transfusion of infected or incompatible blood the two methods differed in opposite directions with Doppler reading from 30-200% of CBF. Transfusion of chilled blood caused CBFV to overestimate 15% and heated blood caused 20% underestimation. These results could be explained by diameter changes in response to variation in myogenic tone or vasoactive substances. CBFV measurements could be seriously misleading in severe clinical derangements where neonatal brain damage might occur. 相似文献
76.
Near-infrared (NIR) spectroscopy was used to measure blood oxygen saturation (SO2)in vivo, in normal rat brain and in subcutaneously-implanted rat 9L gliosarcoma. Changes in cranial and tumor blood SO2 were measured during lethal pentobarbital overdose. After sacrifice, SO2 of cranial blood fell rapidly to a mean of 5.0% of the pre-sacrifice values, whereas SO2 of tumor blood stabilized at a mean of 72.4% of the pre-sacrifice values. This suggests that oxygen consumption by tumor is very low compared to brain. Cranial blood had a higher SO2 than tumor blood before sacrifice (p=0.03), and a lower SO2 after sacrifice (p=0.02). The magnitude of the change in SO2 after sacrifice was greater in normal brain than in tumor (p=0.02), showing that brain tissue uses a greater proportion of the oxygen in ischemic blood than does tumor tissue.To determine the effect of carmustine (BCNU) treatment on tumor and cranial blood SO2, we compared BCNU-treated rats with sham-treated rats. Continuous NIR measurements before and immediately following treatment (ie. over 30–60 min) showed that tumor blood SO2 tended to increase after BCNU treatment, whereas SO2 tended to decrease following sham-treatment. The difference in SO2 between treated and control tumors was significant at 60 min (p=0.02). Thus BCNU treatment can potentially result in immediate increases in tumor oxygenation. The increase in treated tumor blood SO2 occurred despite the fact that there was no change in cranial blood SO2 even at day 4 following treatment. Tumor blood SO2 was inversely correlated with tumor size (p=0.001), confirming that blood is more poorly oxygenated in large tumors. 相似文献
77.
Carlier SG de Korte CL Brusseau E Schaar JA Serruys PW van der Steen AF 《Journal of cardiovascular risk》2002,9(5):237-245
Intravascular ultrasound elastography is a method for measuring the local elastic properties of coronary atherosclerotic plaques using intravascular ultrasound (IVUS). Mechanical properties of the different tissues within a plaque are measured through strain. In the last decade, several groups have applied elastography intravascularly with various levels of success. In this paper, the approaches of the different research groups will be discussed and the focus will be on our approach to the application of intravascular elastography. 相似文献
78.
Silveira E Skoog I Sundh V Allebeck P Steen B 《Social psychiatry and psychiatric epidemiology》2002,37(1):13-22
Background Comparative epidemiological studies in migrants in Sweden have shown increased prevalence of psychosocial morbidity in young adults, but there is paucity of information on health in people aged 65 years and over. Aims We aim to compare prevalence of mental, physical and social health problems, rates of hospital admission, and mortality in Swedish and non-Swedish born people aged 70 years living in Göteborg, Sweden, and examine associations between social factors, physical health, mood and life satisfaction in the ethnic groups. In addition, we aim to test for the hypothesis that differences in mental health between migrants and natives are explained by social disadvantages rather than ethnicity. Method Semi-structured interviews were administered to 84 migrants (47 women and 37 men randomly selected) with the help of bilingual interpreters, and 409 Swedes (183 males and 226 females) used as “controls”. Complementary health and social data obtained from official sources on the total sample (N = 764, including non-participants in overall medical interviews) were used in comparative analyses of in-patient care and mortality and to check for the possibility of sampling bias. Results Migrants – originating mainly from Estonia, Poland, Yugoslavia, Germany, Italy and Nordic countries other than Sweden – reported more dizziness, poor vision and urinary problems, and fewer gall bladder problems than indigenous people (p ≤ 0.05). Migrants also had higher levels of anxiety and depression and bodily pain, and lower levels of general health, social and emotional functioning, satisfaction with physical health status, family contacts, housing conditions and economic status than natives (p ≤ 0.05). Satisfaction with physical health seemed to be one of the strongest factors related to a lower prevalence of anxiety and depression together with family support and time spent in leisure pursuits. No significant differences in in-patient care in several ICD categories and all-cause mortality were found between overall migrants and the control group notwithstanding differences in self-reported health. Conclusion The results indicate poorer subjective health in older migrants than natives in Göteborg, and also point to a “healthy migrant” effect on survival. 相似文献
79.
Twenty-eight patients suffering from cystic fibrosis, with an age range of 8-21 years entered a randomised cross-over trial to study the efficacy of the Positive Expiratory Pressure (PEP) mask as a method of chest physiotherapy, both on its own and in conjunction with other physiotherapy techniques. Twenty-four of these patients completed the trial consisting of 4 treatment programmes each lasting one month and with no wash-out period between them. Five of these patients went on to a fifth programme of Forced Expiratory Technique (FET) alone. At the end of the trial, no significant difference was found between the programmes as regards growth, Shwachman score, Chrispin-Norman score or pulmonary function tests. Twenty-three patients chose to continue using the PEP mask in conjunction with FET long-term as their chest physiotherapy programme as they felt it was an effective treatment allowing increased independence, with postural drainage being kept to a minimum. 相似文献
80.
Olsen J Bjørnsdottir I Tjørnelund J Honoré Hansen S 《Journal of pharmaceutical and biomedical analysis》2002,29(1-2):7-15
Drugs may be metabolised to reactive electrophilic species that spontaneously react with proteins. The presence of such drug-protein adducts has been associated with drug toxicity. In this study, the reactivity of the major metabolite of naproxen--the 1-beta-O-glucuronide (Nap-GlcU)--was compared to the corresponding naproxen coenzyme A (Nap-CoA) thioester. The reactivity of the two metabolites was assessed in vitro in a phosphate buffer (pH 7.4; 0.1 M) at 37 degrees C towards the model bionucleophiles glutathione and human serum albumin (HSA). The reaction between the electrophilic species (Nap-GlcU and Nap-CoA) and glutathione forming the Nap-glutathione conjugate was monitored using LC-MS-MS and LC-UV, respectively. It was shown that Nap-CoA resulted in an approximate 100-fold higher formation of Nap-glutathione conjugate than Nap-GlcU. The presence of Nap-CoA also resulted in acylated HSA with a rate and a yield that was significantly higher than reported for Nap-GlcU. In summary, the data suggest that CoA metabolites may be more reactive species than acyl glucuronides that previously have been associated with severe drug related side effects in vivo. 相似文献