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991.
Kuipers PW Kamphuis ET van Venrooij GE van Roy JP Ionescu TI Knape JT Kalkman CJ 《Anesthesiology》2004,100(6):1497-1503
BACKGROUND: Intrathecal administration of opioids may cause lower urinary tract dysfunction. In this study, the authors compared the effects of morphine and sufentanil administered intrathecally in a randomized double-blind fashion (two doses each) on lower urinary tract function in healthy male volunteers. METHODS: Urodynamic evaluation was performed before and every hour after drug administration up to complete recovery of lower urinary tract function using pressure and flow measurements recorded from catheters in the bladder and rectum. Sense of urge and urinary flow rates were assessed every hour by filling the bladder with its cystometric capacity and asking the patient to void. Full recovery was defined as a residual volume of less than 10% of bladder capacity and a maximum flow rate within 10% of the initial value. RESULTS: Intrathecal administration of both opioids caused dose-dependent suppression of detrusor contractility and decreased sensation of urge. Mean times to recovery of normal lower urinary tract function were 5 and 8 h after 10 or 30 microg sufentanil and 14 and 20 h after 0.1 or 0.3 mg morphine, respectively. This recovery profile can be explained by the spinal pharmacokinetics of both opioids. CONCLUSIONS: Intrathecal opioids decrease bladder function by causing dose-dependent suppression of detrusor contractility and decreased sensation of urge. Recovery of normal lower urinary tract function is significantly faster after intrathecal sufentanil than after morphine, and the recovery time is clearly dose dependent. 相似文献
992.
An RCT of early intervention in
psychosis: Croydon Outreach and Assertive Support Team
(COAST) 总被引:1,自引:0,他引:1
Kuipers E Holloway F Rabe-Hesketh S Tennakoon L;Croydon Outreach Assertive Support Team 《Social psychiatry and psychiatric epidemiology》2004,39(5):358-363
BACKGROUND: Despite considerable interest in early intervention in psychosis, the evidence base for its effectiveness is sparse.We aimed to evaluate a new service in South London, UK, Croydon Outreach and Assertive Support Team (COAST) using a randomised controlled trial (RCT) during its first year. METHOD: Referrals were taken from local adult community mental health teams of those with documented first service contact in the last 5 years and a diagnosis of any functional psychosis. Those who consented (N = 59) were randomised to COAST or treatment as usual (TAU). COAST offered a range of interventions, including optimum atypical medication, psychological interventions (individual cognitive behavioural therapy and family intervention if appropriate) and a range of vocational and welfare help according to need. Whole team training was used to be able to offer these kinds of interventions. RESULTS: Outcomes were evaluated at baseline, 6 months and 9 months on a range of standardised clinical and social measures. Overall both COAST and TAU clients improved over time, but there were no significant improvements for COAST clients; a lack of significant results in the time x treatment interaction. There was a trend for COAST carers' quality of life to increase. Bed days were also less in COAST, but not significantly so. CONCLUSIONS: The lack of clearly demonstrated improvements for COAST is consistent with the published literature so far. The fact that both groups improved in symptoms and functioning over the year suggests that while access to early intervention is helpful, community adult mental health teams should aim to offer high quality input at any stage of psychosis in order to meet client and carer needs. 相似文献
993.
BACKGROUND: Inclusion of cardiac output and other physiologic parameters, in addition to or instead of, demographic variables might improve the population pharmacokinetic modeling of lidocaine. METHODS: Thirty-one patients were included in a population pharmacokinetic study of lidocaine. After bolus injection of lidocaine (1 mg/kg), 22 or 10 blood samples per patient were taken from a radial artery. During the experiment, cardiac output was measured using a thoracic electrical bioimpedance method. The following four population pharmacokinetic models were constructed and their performances investigated: a model with no covariates, a model with cardiac output as covariate, a model with demographic covariates, and a model with both cardiac output and demographic characteristics as covariates. Model discrimination was performed with the likelihood ratio test. RESULTS: Inclusion of cardiac output resulted in a significant improvement of the pharmacokinetic model, but inclusion of demographic covariates was even better. However, the best model was obtained by inclusion of both demographic covariates and cardiac output in the pharmacokinetic model. CONCLUSIONS: When population pharmacokinetic models are used for individualization of dosing schedules, physiologic covariates, e.g., cardiac output, can improve their ability to predict the individual kinetics. 相似文献
994.
Weijnen CF De Wit NJ Numans ME Kuipers EJ Hoes AW Verheij TJ 《Alimentary pharmacology & therapeutics》2001,15(8):1205-1210
AIM: To identify the most accurate and efficient test for diagnosing Helicobacter pylori infection in primary care patients. STUDY DESIGN: A whole blood test, an ELISA, and carbon13 urea breath test (CUBT) were evaluated in a primary care setting and validated against two different gold standards that used gastric biopsies. POPULATION: Primary care patients who had dyspeptic complaints lasting at least 2 weeks and were referred for endoscopy. OUTCOMES MEASURED: Positive and negative predictive values, sensitivity and specificity were determined for all three noninvasive H. pylori tests. RESULTS: Data from the three non-invasive H. pylori tests were available for 136 primary care dyspeptic patients referred for endoscopy. They were compared with data from the gold standards. The positive predictive value of the whole blood test was in the range 71-75%, the ELISA 83-86%, and the CUBT 88-92%, while the negative predictive values were in the ranges 72-77%, 96-100%, and 95-98%, respectively. The sensitivity of the whole blood test was in the range 36-42%, the ELISA 93-100%, and the CUBT 92-97%, while the specificities were in the ranges 92-93%, 90-91% and 93-95%, respectively. The positive predictive value of the ELISA dropped significantly at lower H. pylori infection rates. DISCUSSION: Both the ELISA and CUBT are effective in the primary care setting, while the whole blood tests produces inferior results. ELISA might, however, be less suitable for detecting H. pylori infection in a population with a low rate of infection. 相似文献
995.
Bile formation and cholestasis 总被引:1,自引:0,他引:1
Transport proteins in hepatocytes and bile duct epithelium mediate uptake and secretion of cholephilic compounds in the liver and are involved in bile formation. Many of these proteins have recently been cloned and characterized and appear to belong to large gene families. Apart from the liver these proteins are expressed in the blood-brain barrier, placenta, kidneys, lungs, intestine and seminiferous tubules. Prokaryotes and yeasts contain similar proteins. In cancer cells they are involved in multidrug resistance. Some genetic cholestatic liver diseases, including progressive familial intrahepatic cholestasis, Dubin-Johnson syndrome, benign recurrent intrahepatic cholestasis and intrahepatic cholestasis of pregnancy result from mutations in transport protein genes. These proteins also play a role in drug-induced liver disease and in primary biliary cirrhosis. Cyclosporine and oestradiol (glucuronide) for instance inhibit bile salt export protein (BSEP). 相似文献
996.
RC Tait EJ Ladusans M El-Metaal RG Patel AM Will 《Archives of disease in childhood》1996,74(3):228-231
The lack of oral anticoagulant guidelines specific to paediatric practice has led to the adoption of adult regimens, often without scientific evidence of efficacy or safety. A two year prospective study of anticoagulant control was carried out in 45 children aged 9 months to 18 years, the majority of whom were receiving primary prophylactic anticoagulation. The main indication was congenital heart disease, either with (n = 8) or without (n = 34) mechanical valve prosthesis. During a follow up period of 602 patient months the average interval between visits was three weeks. Target international normalised ratios (INRs) were achieved on 62% and 39% of visits for children with low target INR (2.0-3.0) and high target INR (3.0-4.0) respectively. However warfarin dose was altered on only 22% of visits. Warfarin doses required to achieve a stable INR of 2.0-3.0 in 33 children were strongly correlated with weight [dose (mg/d) = 0.07 x weight (kg) + 0.54] but independently influenced by age. No thrombotic complications were recorded, and haemorrhagic events were infrequent (2.1% of visits) and, with one exception, minor. Safe outpatient oral anticoagulation is feasible in children, whose warfarin requirements appear moderately predictable and whose control is no more erratic than that of adults. 相似文献
997.
Pathways of tumor spread through the lung: radiologic correlations with anatomy and pathology 总被引:7,自引:0,他引:7
The pathways of tumor spread through the lung are described and their significance for radiographic interpretation is illustrated. A key to understanding the spread of bronchogenic carcinoma is the realization that although the normal flow of lymph in the pulmonary lymphatics is centripetal, lymphatic obstruction can cause reversal of flow. As a result, tumor cells are commonly carried centrifugally to the periphery in lymphatics or the connective tissue around them, and remote pleural involvement, secondary parenchymal masses, or satellite nodules may develop. Failure to appreciate peripheral spread of tumor has negative consequences for tumor staging, surgery, and radiotherapy. In the absence of hilar node involvement causing obstruction, long line shadows more than 0.5 inch (1.25 cm) in length proximal to a peripheral mass very infrequently represent tumor. 相似文献
998.
Acute effects of pentobarbital-anaesthesia on bile secretion 总被引:3,自引:0,他引:3
F Kuipers T Dijkstra R Havinga W van Asselt R J Vonk 《Biochemical pharmacology》1985,34(10):1731-1736
Male Wistar rats were equipped with permanent catheters in the bile duct and the duodenum under ether anaesthesia, at least seven days before the experiments. By this technique, the enterohepatic circulation can be interrupted for bile collection without direct surgical intervention. 14C-Pentobarbital (26.6 mumole/100 g body wt) was injected intraperitoneally immediately before interruption of the enterohepatic circulation (NBD, Non-Bile Diverted) or after eight days of bile diversion (BD, Bile Diverted). In NBD rats, bile flow and biliary bile acid excretion were significantly reduced during the first hour after pentobarbital administration when compared to unanaesthetized controls, but markedly increased thereafter. Pentobarbital treatment slightly decreased biliary bile acid excretion in BD rats, but caused a 60% increase in bile flow. Within four hours 22.3 +/- 0.4% and 26.0 +/- 2.7% of the injected radioactivity was excreted into bile in NBD and BD rats, respectively. The calculated osmotic activity of pentobarbital and its metabolites was 47.8 +/- 5.2 microliter/mumole in NBD rats and 37.8 +/- 1.3 microliter/mumole in BD rats. Consequently, pentobarbital treatment affected the bile acid independent fraction of bile flow (BAIF). The calculated BAIF was 2.68 microliter/min/100 g body wt in unanaesthetized animals, but 4.27 microliter/min/100 g body wt in pentobarbital treated NBD rats. Corresponding values for BD rats were 1.70 and 2.38 microliter/min/100 g body wt. It is concluded that pentobarbital anaesthesia affects bile production in the rat by direct and indirect means. Firstly, pentobarbital and its metabolites are rapidly excreted into bile and exert a significant choleretic effect, thereby increasing the BAIF. Secondly, pentobarbital anaesthesia retards the exhaustion of the intestinal bile acid pool, which leads to secondary changes in the biliary excretion process. 相似文献
999.
Differing responses of globin and glycophorin gene expression to hemin in the human leukemia cell line K562 总被引:3,自引:0,他引:3
Tonkonow BL; Hoffman R; Burger D; Elder JT; Mazur EM; Murnane MJ; Benz EJ Jr 《Blood》1982,59(4):738-746
The human leukemia cell line, K562, produces embryonic and fetal hemoglobins and glycophorin A, proteins normally associated only with erythroid cells. Hemoglobin accumulation is enhanced by exposure of the cells to 0.05 mM hemin. We have examined K562 cells before and after exposure to hemin to determine whether expression of these erythroid proteins was shared by all cells or confined to specific subpopulations. Globin gene expression was examined by quantitation of globin mRNA sequences, using a 3H-globin cDNA molecular hybridization probe. Constitutive cells produced globin mRNA, the content of which was increased 3-4-fold by hemin. Cell-to-cell distribution of globin mRNA was determined by in situ hybridization of 3H-globin cDNA to constitutive and hemin-treated K562 cells. Virtually all cells in the culture exhibited grain counts above background, indicating globin gene expression by all cells, rather than a confined subpopulation. Virtually all hemin-treated cells had 3-5-fold higher grain counts, indicating uniformly increased globin gene expression. The glycophorin content of K562 cells was estimated by fluorescence-activated cell sorting (FACS) of cells labeled with fluorescein-labeled antiglycophorin antiserum. The vast majority of constitutive cells contained glycophorin, but exhibited to apparent increase in glycophorin accumulation after hemin exposure. Thus, glycophorin and globin genes exhibited differential responses to hemin. These differences could reflect normal differences in the patterns of specialized gene expression in stem cells. Alternatively, different aberrations of gene expression could be occurring in response to the determinants of the neoplastic properties of K562. 相似文献
1000.
Tj. Kuipers 《International journal of radiation oncology, biology, physics》1982,8(6):1011-1017
Radiation therapy of cervix carcinoma is applied in this Institute by means of a modified Stockholm method in combination with external beam irradiation. In 1968, parametrial portals were replaced by large planparallel opposed fields extending cranially to LIII/LIV with central shielding in order to avoid overdosage in the area of intracavitary treatment. This resulted in a marked increased incidence of severe sigmoid-colon radiation lesions from 0.25% to 4%; predominantly in Stage I and It patients. Therefore two measures have been introduced: beginning in 1972 measures were taken to prevent the cranial displacement of the uterus during intracavitary treatment in order to shortening the distance between the radioactive sources and the sigmoid-colon; from 1973 stereo X ray photogrammetry (SRM) was applied for dose determinations at points of the sigmoid-colon, which were seen to be located close to the applicator. When SRM data indicated that a high dose at the sigmoid-colon might occur, treatment modifications enabled prevention of radiation damage. Change of position of the applicator was the first to be considered. In the last seven years no surgical intervention had to be performed because of a sigmoid-colon lesion resulting from an unexpected high radiation dose delivered by intrauterine sources. The local recurrence rate was not increased following treatment modifications for prevention of sigmoid-colon radiation damage. 相似文献