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991.
BACKGROUND: Urticarial patients are usually treated with oral antihistamines and 50% respond well to this treatment; however, the other 50% do not respond to antihistamines and need a more aggressive approach, such as short or prolonged courses of oral corticosteroids or cyclosporine. Potential adverse effects, however, limit this regimen. OBJECTIVE: To determine the efficacy of mycophenolate mofetil, an immunomodulatory drug, in the treatment of patients with severe chronic urticaria. METHODS: In an open-label, uncontrolled trial, nine patients with documented chronic urticaria who had been treated previously with antihistamines and/or corticosteroids with poor response were enrolled in the trial. After 2 weeks of baseline assessment, patients received 1000 mg twice daily of mycophenolate mofetil for 12 weeks. Improvement was monitored using the urticarial activity score, which is the sum of the wheal number score and itch severity score. Patients also recorded their daily need for other medications to control allergic symptoms. RESULTS: There was a significant decrease in the urticarial activity score relative to the baseline assessment at the end of the study period (P < 0.001). All patients were able to stop prednisone on completion of the study. There was also a decrease in antihistamine dose, but this did not reach statistical significance. Treatment with mycophenolate mofetil was not associated with significant adverse effects. CONCLUSIONS: Mycophenolate mofetil may be a valuable and safe treatment for patients with chronic urticaria who do not respond to antihistamines and/or corticosteroids, and who require aggressive treatment to control their disease symptoms. Further controlled clinical studies are needed to determine its value.  相似文献   
992.
Previous investigations have suggested that probenecid (PRB) alters the in vivo disposition of valproic acid (VPA), perhaps by inhibiting hepatic formation of valproate glucuronide (VG). Because VPA and PRB bind moderately to plasma proteins, protein binding also is a potential locus of interaction. The purpose of this investigation was to determine whether in vitro systems could accurately predict PRB-associated perturbations in the hepatobiliary disposition of VPA and VG in vivo. VPA and PRB were coadministered to rats for 60 min at various infusion rates to examine steady-state VPA disposition. PRB did not alter the binding of VPA in serum or hepatic cytosol. However, PRB decreased the apparent intrinsic clearance of VPA (1.81 +/- 0.58 versus 1.23 +/- 0.23 ml/min; P =.025) by competitively inhibiting VPA elimination. In a separate study, rat hepatic S9 fractions were incubated with VPA (7.2-721 microg/ml) and PRB (0-2850 microg/ml). VG formation (V(max) = 0.80 +/- 0.06 microg/min/mg of protein; K(m) = 173 +/- 28.8 microg/ml) was impaired by PRB in a competitive manner (K(i) = 876 +/- 559 microg/ml), consistent with the in vivo data. Despite inhibition of phase II metabolism of VPA to VG by PRB, the VG biliary excretion rate at similar unbound VPA concentrations in hepatic cytosol was not lower in PRB-treated rats. These results indicate that VG disposition in the presence of PRB cannot be predicted accurately based solely on in vitro inhibition of glucuronidation and emphasize the complexity of processes associated with the hepatobiliary system.  相似文献   
993.
Herpesviruses can cause an acute, subacute, or chronic disease state in both immunocompetent and immunocompromised individuals. Herpes simplex virus (HSV) encephalitis is most often an acute monophasic disease process. Rarely, however, it may progress to a chronic state, and more rarely still to a granulomatous encephalitis. Prior studies have suggested that antiviral immunity with Toll-like receptors determines susceptibility to herpesviruses. The authors report the case of a 14-year-old girl with a remote history of treated HSV encephalitis, who had intractable seizures and worsening MR imaging changes that were concerning for either a neoplastic or an inflammatory process. She was found to have granulomatous herpes simplex encephalitis and had a low cytokine response to Toll-like receptor 3 stimulation.  相似文献   
994.
BACKGROUND: The Centers for Disease Control and Prevention is embarking on a program of biannual venue-based time-space sampling surveys to monitor prevalence and incidence of HIV among men who have sex with men (MSM). GOAL: We examine the efficacy of the suggested methodology in terms of population coverage, sample period, range of venues, and representativeness. STUDY: The 2002 Urban Men's Health Study (N = 879) is a telephone interview of a household probability sample of adult MSM living in San Francisco. RESULTS: A 6-month bar/club sample would capture 79% of the adult MSM population and yield an accurate estimate of HIV prevalence. Using a longer sample period or sampling other less-frequented venues yields marginal improvement. Risk behavior, when broadly defined, is overestimated. CONCLUSIONS: The National HIV Behavioral Surveillance of MSM protocol may be satisfactory for sampling urban MSM within defined limits, but could be conducted at significantly less cost by reducing the types of venues and fielding time. However, bias in the venue sample with respect to risk behavior and other key correlates argues for validity checks based on household probability samples conducted at infrequent intervals.  相似文献   
995.
The earliest stages of acne keloidalis are not well characterized. In the present study, transverse sections of the early lesions revealed follicular units in several stages of inflammation. These follicles surrounded the central follicular units that gave rise to the clinically evident papule. Despite a spectrum of inflammatory changes, the most marked inflammation consistently occurred in the deep infundibular and isthmian levels of the hair follicles. Two follicles, presumably in the earliest stage, exhibited primarily an acute folliculitis and perifolliculitis, with destruction of the follicular wall and the release of hair. Central follicles showed predominantly acute neutrophilic or chronic lymphocytic inflammation at the upper isthmian levels and granulomatous inflammation at the deeper isthmian levels. Other follicles showed scar at the isthmian levels trapping hair fragments in the inferior portion of the follicle, with granulomatous inflammation and scarring. Sebaceous glands were absent in all stages of folliculitis in seven of eight follicular units.  相似文献   
996.
Despite increasing discussion about the dental care setting as a logical, potentially fruitful venue for rapid HIV testing, dentists’ willingness to take on this task is unclear. Semistructured interviews with 40 private practice dentists revealed their principal concerns regarding offering patients HIV testing were false results, offending patients, viewing HIV testing as outside the scope of licensure, anticipating low patient acceptance of HIV testing in a dental setting, expecting inadequate reimbursement, and potential negative impact on the practice. Dentists were typically not concerned about transmission risks, staff opposition to testing, or making referrals for follow-up after a positive result. A larger cultural change may be required to engage dentists more actively in primary prevention and population-based HIV screening.An estimated one fifth of Americans infected with HIV, approximately 250 000 individuals, are unaware of their status.1 Consequently, individuals are often diagnosed only when their disease has progressed and they are symptomatic2 or they already have AIDS. The advent of the rapid HIV test has made it possible to offer HIV testing in a much wider array of settings, thus creating the opportunity for more infected individuals to be identified earlier. Paltiel et al.3 estimated that widespread routine HIV screening would extend survival by 1.5 years for the average detected HIV-infected individual who enters care. Furthermore, studies have also shown that most persons who learn that they are HIV positive reduce sexual risk behaviors, resulting in reduced transmission to others.4–6The rapid HIV test is a fast, reliable, simple, and cost-effective method to screen for HIV,7–11 yielding results typically in 20 minutes or less and relieving burdens on both patients and providers that arise from the need for tested persons to return later to obtain results. Although it is a screening test, and therefore a reactive-positive result must be confirmed with traditional testing, it has been shown to be comparable to the traditional Western blot in sensitivity and specificity.11 The Food and Drug Administration approved the rapid HIV test using whole blood from a finger stick in 200212 and using oral fluid in 2004.13 Rapid testing is now the preferred method for many providers and clients. Oral fluid collection for testing has demonstrated high acceptability in preliminary studies with various risk groups.14–18 Given the availability of a safe, reliable, and acceptable rapid test for HIV, and recognizing the value for both individuals and public health of identifying undiagnosed cases of HIV infection as early as possible, in 2006 the Centers for Disease Control and Prevention issued revised recommendations for HIV testing.19 In the recommendations, they advocated that all individuals aged 13 to 64 years be routinely tested in all private and public health care settings and that HIV testing be included among the routine prenatal tests pregnant women take.  相似文献   
997.
In order for the global healthcare system to remain sustainable, healthcare spending needs to be reduced, and self-treating certain conditions under the guidance of a pharmacist provides a means of accomplishing this goal. This article was developed to describe global healthcare trends affecting self-care with a specific focus on the role of the pharmacist in facilitating over-the-counter (OTC) medication management. Potential healthcare-related economic benefits associated with the self-care model are outlined. The importance of the collaboration between healthcare providers (HCPs), including specialists, primary care providers, and pharmacists, is also discussed. The evolving role of the pharmacist is examined and recommendations are provided for ways to successfully engage with other HCPs and consumers to optimize the pharmacist’s unique qualifications and accessibility in the community. Using the management of frequent heartburn with an OTC proton-pump inhibitor as a model, the critical role of the pharmacist in patient self-treatment of certain symptoms will be discussed based on the World Gastroenterology Organization’s recently published guidelines for the community-based management of common gastrointestinal symptoms. As the global healthcare system continues to evolve, self-care is expected to have an increasing role in treating certain minor ailments, and pharmacists are at the forefront of these changes. Pharmacists can guide individuals in making healthy lifestyle choices, recommend appropriate OTC medications, and educate consumers about when they should consult a physician. Funding: Pfizer Inc.  相似文献   
998.
999.
Recent attention to the increasing incidence of venous thromboembolism has included a call to action from the surgeon general and new guidelines from various specialty organizations. The standard of care for treatment of deep venous thrombosis in the emergency department (ED), supported by the 2008 American College of Chest Physicians (ACCP) guidelines, involves initiation of anticoagulation with low-molecular-weight heparin, pentasaccharide, or unfractionated heparin. For selected appropriate patients with extensive acute proximal deep venous thrombosis, the ACCP guidelines now recommend thrombolysis in addition to anticoagulation to reduce not only the risk of pulmonary embolism but also the risk of subsequent postthrombotic syndrome and recurrent deep venous thrombosis. Postthrombotic syndrome is a potentially debilitating chronic cluster of lower-extremity symptoms occurring in 20% to 50% of deep venous thrombosis patients subsequent to the acute insult, sometimes not until years later. A strategy of early thrombus burden reduction or frank removal might reduce the incidence of postthrombotic syndrome, as per natural history studies, venous thrombectomy data, observations after systemic and catheter-directed thrombolysis, and the still-limited number of randomized trials of catheter-directed thrombolysis (with anticoagulation) versus anticoagulation alone. Contemporary invasive (endovascular) treatments mitigate the drawbacks historically associated with thrombolytic approaches by means of intrathrombus delivery of drugs with greater fibrin specificity and lower allergenicity, followed by mechanical dispersion to accelerate lysis and then aspiration of remaining drug and clot debris. With a 2016 target completion date, the National Heart, Lung, and Blood Institute--sponsored Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter-Directed Thrombolysis trial is comparing the safety and efficacy, in terms of both deep venous thrombosis and postthrombotic syndrome parameters, of the most evolved pharmacomechanical catheter-directed thrombolysis devices versus standard anticoagulation therapy alone. This article reviews the grounds for use of adjunctive thrombolysis in patients with acute proximal deep venous thrombosis and begins to identify types of deep venous thrombosis patients encountered in the ED who might benefit most from multidisciplinary consideration of early referral for possible endovascular therapy.  相似文献   
1000.
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