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41.
42.
1. The vasoconstrictor responses of isolated intrapulmonary arteries (IPA) to P2-receptor agonists was investigated during adaptation to extrauterine life in the normal piglet and the effect of pulmonary hypertension was studied following exposure of newborn animals to chronic hypobaric hypoxia (51 kPa) for 3 days. 2. At resting tone, alpha,beta-methyleneATP (alpha,beta-meATP) (P2X-receptor agonist) contracted intrapulmonary arteries from adult, but not immature pigs, and repeated application desensitized the response. 3. Adenosine 5'-triphosphate (ATP) induced endothelium-independent relaxation at low concentrations at all ages, a variable contractile response to high concentrations developed by 3 days, becoming larger and consistent by 14 days of age. 4. Uridine 5'-triphosphate (UTP) evoked a contractile response in normal intrapulmonary arteries from foetal to adult life, the magnitude of the response increasing with age. Endothelial removal and pre-incubation with Nomega-nitro-L-arginine methyl ester (L-NAME) (100 microM) increased the contractile response of adult vessels. 5. Pre-incubation with alpha,beta-meATP (100 microM), increased the contractile response to UTP in both newborn and adult vessels. ATP-induced relaxations were reduced in newborn vessels but there was no effect on the responses of adult vessels. 6. Responses to UTP, ATP and alpha,beta-meATP of intrapulmonary arteries from newborn piglets exposed to chronic hypobaric hypoxia for 3 days were normal. 7. In summary, UTP elicited marked vasoconstriction of porcine IPA at all ages. UTP and ATP responses were consistent with activation of the P2Y4-receptor recently identified in vascular smooth muscle by others. alpha, beta-meATP induced a small vasoconstriction in the adult probably via the P2X1-receptor. Responses remained normal in neonatal pulmonary hypertension.  相似文献   
43.
AIMS: To determine the clinical performance of three cerebrospinal fluid (CSF) IgG synthesis formulae using data obtained from two quantitation methods. METHODS: Receiver operator characteristic (ROC) analysis and decision index plots were used to compare a rate nephelometric (RN) and a rocket immunoelectrophoretic (RIEP) method for quantitating albumin and IgG for use in CSF IgG synthesis formulae. Further analysis was used to determine the most clinically accurate of these formulae for a diagnosis of multiple sclerosis with regard to technical accuracy and cost effectiveness. RESULTS: Values for albumin and IgG determined by RN gave better sensitivities and specificities than the RIEP method when applied to all three formulae; however, when the 95% confidence limits were considered, the difference was not significant. Using the RN method with an agreed "rule in" threshold value of 90% specificity, the IgG index gave the best clinical performance. CONCLUSION: ROC curve analysis and decision index plots provide valuable tools in assessing and comparing the clinical performance of new and existing laboratory assays.  相似文献   
44.
We report here a patient with acute mycloid leukaemia who relapsed 20 months after undergoing a double autograft procedure in first remission. He was reinduced and subsequently underwent a third autologous bone marrow transplantation in second remission using bone marrow harvested in second remission and a Busulphan and Cyclophosphamide conditioning regimen. Although the engraftment was very slow, he has remained in second remission for 34+ months. This case demonstrates that durable disease-free survival can be attained by a second preparative therapy, even in second remission, for patients relapsed after autologous bone marrow transplantation.  相似文献   
45.
It has been demonstrated recently in mycosis fungoides and lichen planus that T lymphocyte subsets may be identified in cutaneous lymphocytic infiltrates using the immunoperoxidase technic in conjunction with monoclonal antibodies produced by the technic of Kohler and Milstein. This communication describes the application of this technic to cutaneous lymphoid infiltrates of parapsoriasis in which T cell predominance has been demonstrated previously. The lymphoid infiltrates of six patients with atrophic parapsoriasis were examined by the indirect immunoperoxidase technic using monoclonal antibodies (from two commercial sources) directed against "helper" and "suppressor" T cell subsets. Both "helper" and "suppressor" cells (as defined by a positive reaction with monoclonal antibodies) could be identified in cutaneous infiltrates. "Helper" cells predominated, but in varying degrees among patients. The relevance of these findings in relation to the possible development of clinical mycosis fungoides from atrophic parapsoriasis is discussed. In addition, factors causing difficulty in the consistent identification of cell subtypes are discussed. These factors suggest that in the present state of imperfection, difficulty will be experienced in using this technic for the accurate quantification of percentages of lymphocyte subsets in tissue sections.U  相似文献   
46.
Pigeons responding under a variable-interval (VI) 75-s schedule of food presentation were used to study cross-tolerance from 9-tetrahyrocannabinol (9-THC) to pentobarbital and barbital. After initial dose-effect functions for pentobarbital and barbital were determined, the birds received 9-THC injections for 6 weeks. This chronic administration regimen resulted in a greater than 100-fold tolerance to 9-THC. Redetermination of the pentobarbital and barbital dose-effect functions during the chronic 9-THC regimen revealed statistically significant shifts to the right for the pentobarbital (0.191 log unit) and barbital (0.078 log unit) dose-effect curves. All six birds showed tolerance to pentobarbital, while four of the six showed tolerance to barbital. Blood barbital levels before and after chronic 9-THC administration did not differ significantly. Tolerance to 9-THC was more prolonged and of much greater magnitude than the cross-tolerance to pentobarbital or barbital. The results demonstrate that cross-tolerance can develop from 9-THC to a barbiturate that normally undergoes little metabolism.  相似文献   
47.
The present study examined the degree to which event related rumination, a quest orientation to religion, and religious involvement is related to posttraumatic growth. Fifty-four young adults, selected based on prescreening for experience of a traumatic event, completed a measure of event related ruminations, the Quest Scale, an index of religious participation, and the Posttraumatic Growth Inventory. The three subscales of the Quest Scale, the two groups of rumination items (soon after event/within past two weeks), and the index of religious participation were entered in a standard multiple regression with the total score of the Posttraumatic Growth Inventory as the dependent variable. The degree of rumination soon after the event and the degree of openness to religious change were significantly related to Posttraumatic Growth. Congruent with theoretical predictions, more rumination soon after the event, and greater openness to religious change were related to more posttraumatic growth. Present findings offer some confirmation of theoretical predictions, and also offer clear direction for further research on the relationships of religion, rumination, and posttraumatic growth.  相似文献   
48.
Beacon: a novel gene involved in the regulation of energy balance   总被引:3,自引:0,他引:3  
The hypothalamus plays a major role in the control of energy balance via the coordination of several neuropeptides and their receptors. We used a unique polygenic animal model of obesity, Psammomys obesus, and performed differential display polymerase chain reaction on hypothalamic mRNA samples to identify novel genes involved in obesity. In this study, we describe a novel gene that encodes a small protein we have termed "beacon." Beacon mRNA gene expression in the hypothalamus was positively correlated with percentage of body fat. Intracerebroventricular infusion of beacon resulted in a dose-dependent increase in food intake and body weight and an increase in hypothalamic expression of neuropeptide Y (NPY). Simultaneous infusion of beacon and NPY significantly potentiated the orexigenic response and resulted in rapid body weight gain. These data suggest a role for beacon in the regulation of energy balance and body weight homeostasis that may be mediated, at least in part, through the NPY pathway.  相似文献   
49.
Avasimibe, an acyl-CoA:cholesterol acyltransferase inhibitor, has been previously shown to be a potent inducer of CYP3A4 and multiple drug resistance protein 1. We have further characterized the drug interaction potential of avasimibe by studying the inductive and inhibitory effect of this compound on major drug-metabolizing enzymes. Enzymes known to be involved in the metabolism of drugs likely to be coadministered with avasimibe, such as CYP1A1/2, CYP2C, and CYP2B6, were evaluated further by microarray analysis, Western immunoblotting, and activity assays, using rifampicin and beta-naphthoflavone as positive controls. No change was observed in CYP1A1/2 mRNA or activity levels after avasimibe treatment. Differential induction of CYP2C9- and CYP2B6-immunoreactive protein and activity was observed depending on drug concentration and donor. Microarray analysis showed a similar increase in CYP2C and CYP2B6 mRNA levels. The inhibition potential of avasimibe on the major drug-metabolizing enzymes was assessed using pooled human liver microsomes. Avasimibe inhibited CYP2C9 (IC50 2.9 microM), CYP1A2 (IC50 13.9 microM), and CYP2C19 (IC50 26.5 microM). A clinical drug interaction study was conducted to determine whether avasimibe might interact with the CYP2C9 substrate warfarin. Volunteers received 750 mg of avasimibe and showed a 54.2% reduction in trough concentrations of S-warfarin and decreased prothrombin times by 12, 15, 19, and 21% on days 6 through 9, respectively. These results demonstrate that avasimibe's inductive spectrum resembles that of rifampin.  相似文献   
50.
Background: The management of cholangiocarcinoma is continually reviewed on a current evidence basis to develop practice guidelines and consensus statements. However, the standardized treatment guidelines are still unclear for cholangiocarcinoma patients who are listed for liver transplantation. We aimed to validate and evaluate the potential efficacy of chemotherapy combination of Gemcitabine and Cisplatin as a neo-adjuvant treatment for cholangiocarcinoma patients before liver transplantation. Methods: In this prospective case series, patients with locally advanced, unresectable, hilar, or intrahepatic cholangiocarcinoma with no evidence of extrahepatic disease or vascular involvement were treated with a combination of neoadjuvant gemcitabine and cisplatin with no radiation. All patients included received chemotherapy prior to being listed for liver transplantation at a single cancer center according to an open-labeled, and center-approved clinical management protocol. The primary endpoints were the overall survival and recurrence-free survival after liver transplantation. Results: Between 1 March 2016, and 15 March 2022, 10 patients (8 males and 2 females) with a median age of 62.71(interquartile range: 60.02–71.87) had a confirmed diagnosis of intrahepatic or hilar cholangiocarcinoma and underwent liver transplantation. Median days of neoadjuvant therapy for a given combination of gemcitabine and cisplatin were 181 (IRQ: 120–250). Nine patients (90%) were reported with no recurrence or metastasis, and only 1 patient had confirmed metastasis (10%); days for metastasis after transplantation were 612 for this patient. All patients received a combination of gemcitabine and cisplatin as neo-adjuvant while awaiting liver transplantation. The median days of follow-up were 851 (813–967). Overall survival was 100% (95% CI 100–100%) at both years one and two; 75% (95% CI 13–96%) at years three to five. One patient died at eight hundred and eighty-five days. No adverse events were reported after liver transplantation including the patient who was confirmed with recurrence. Conclusions: Our finding demonstrated that neo-adjuvant gemcitabine and cisplatin with no radiation prior to liver transplantation resulted in excellent outcomes for patients with cholangiocarcinoma.  相似文献   
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