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101.
The European Academy of Allergology and Clinical Immunology has proposed a revised terminology for allergic and allergy-related reactions that can be used independently of target organ or patient age group. The proposed terminology is based on the present knowledge of the mechanisms which initiate and mediate allergic reactions. 'Hypersensitivity' is an umbrella term, 'allergy' involves a hypersensitivity reaction which is initiated by an immunological mechanism, and 'atopy' is an individual or familial tendency to produce IgE antibodies in response to low doses of allergens, and is accompanied by the typical symptoms or asthma rhino-conjunctivitis or eczema/dermatitis. Each condition should be categorised as 'allergic/not allergic', and the allergic conditions should be further categorised as 'IgE-mediated/non IgE-mediated' (sometimes: 'IgE-associated'). Terms which are no longer in use include: 'idiosyncrasy' (this will now become 'hypersensitivity'); 'pseudo-allergy' ('non-allergic hypersensitivity'); 'extrinsic', 'intrinsic', 'endogenous' and 'exogenous asthma' ('allergic' (possibly 'IgE-mediated') and 'non-allergic asthma'); 'atopic eczema' ('atopic eczema/dermatitis syndrome': 'allergic (possibly 'IgE-mediated') or 'non-allergic'); 'intrinsic' and 'cryptogenic variants of eczema' ('non-allergic atopic eczema/dermatitis syndrome'); 'food intolerance' ('non-allergic food hypersensitivity') and 'anaphylactoid reaction' ('non-allergic anaphylaxis').  相似文献   
102.
BACKGROUND: In 1999, an extensive study among bell pepper growers showed that a predatory mite, Amblyseius cucumeris, is a potentially relevant source of occupational allergens because 23% of the population had positive skin prick test reactions. OBJECTIVE: To investigate whether cross-reactivity between A. cucumeris and Dermatophagoides pteronyssinus is responsible for the cosensitization to both mite species found in 58.7% of A. cucumeris-sensitized greenhouse workers. METHODS: Fifteen serum samples from greenhouse workers with work-related inhalant allergy and a positive radioallergosorbent test (RAST) reaction to A. cucumeris or D. pteronyssinus were selected for immunoblot analysis using extracts of both mites. A subselection (n = 5) was used for RAST and immunoblot inhibition to investigate potential cross-reactivity. RESULTS: On immunoblot, 2 distinct patterns were observed: one pattern showed common protein bands in A. cucumeris and D. pteronyssinus blots suggestive of cross-reactivity between A. cucumeris and D. pteronyssinus and the other pattern showed no shared protein bands. Dermatophagoides pteronyssinus RAST inhibition with A. cucumeris extract was low in 4 serum samples (<25% inhibition) and nearly absent in 1 serum sample; A. cucumeris RAST inhibition with D. pteronyssinus extract was high in 1 serum sample (75% inhibition), low in 2 serum samples (35% and <15% inhibition), and absent in 2 serum samples. These results were confirmed by immunoblot inhibition experiments. CONCLUSIONS: Amblyseius cucumeris, a new occupational allergen, has species-specific antigens and common antigens that are cross-reactive with the house dust mite D. pteronyssinus.  相似文献   
103.
Nephrin (NHPS1) encodes a transmembrane protein of approximately 1,200 amino acids that plays a critical role in podocyte slit-diaphragm formation and the development of functional mammalian glomerular filtration barriers. In humans and mice with congenital defects in the nephrin gene, the glomerular filtration barrier is defective and protein leakage into the kidney filtrate causes a life-threatening proteinuria. This protein also plays an essential role in the formation of the stellate cells of the Drosophila Malpighian tubules. In this report, the sequence and expression of a Xenopus ortholog of nephrin is described using both conventional and novel three-dimensional (3D) visualization methodologies. Xenopus nephrin encodes a protein of 1,238 amino acids and is expressed at high levels in the forming pronephric kidney glomus, the equivalent of the mammalian glomerulus. Expression commences at stage 25 and is specific to the pronephric glomus up until at least tadpole feeding stages. Two-color fluorescent whole-mount in situ analysis of nephrin expression allowed the 3D shape of the glomus to be imaged and contrasted to the pronephric tubules throughout its morphogenesis. Confocal data processing pipelines were established to generate both volumetric and surface models of the developing pronephros, and a Web-based visualization system was used to generate dynamic and manipulable models of the forming nephric organs. This system allows simple on-line morphometric analysis of the developing pronephric components. As in fish embryos, the glomera first form laterally then migrate medially as the pronephros matures. Unlike in the zebrafish, in Xenopus, this migration stops short of complete fusion of the two glomera at the midline, but a nephrin-positive glomeral nexus does form anteriorly and links the two structures from stage 38 onward.  相似文献   
104.
105.
Light-scattering and viscosity measurements were performed on dilute solutions of polyamide-12 in 1,1,1,3,3,3-hexafluoro-2-propanol at 25°C. The [η]-M?w relationship was determined to be [η]=8,43·10?4·M?w0,68 dl g?1.  相似文献   
106.
Allergen immunotherapy (AIT) has been in use for the treatment of allergic disease for more than 100 years. Asthma treatment relies mainly on corticosteroids and other controllers recommended to achieve and maintain asthma control, prevent exacerbations, and improve quality of life. AIT is underused in asthma, both in children and in adults. Notably, patients with allergic asthma not adequately controlled on pharmacotherapy (including biologics) represent an unmet health need. The European Academy of Allergy and Clinical Immunology has developed a clinical practice guideline providing evidence‐based recommendations for the use of house dust mites (HDM) AIT as add‐on treatment for HDM‐driven allergic asthma. This guideline was developed by a multi‐disciplinary working group using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. HDM AIT was separately evaluated by route of administration and children and adults: subcutaneous (SCIT) and sublingual AIT (SLIT), drops, and tablets. Recommendations were formulated for each. The important prerequisites for successful treatment with HDM AIT are (a) selection of patients most likely to respond to AIT and (b) use of allergen extracts and desensitization protocols of proven efficacy. To date, only AIT with HDM SLIT‐tablet has demonstrated a robust effect in adults for critical end points (exacerbations, asthma control, and safety). Thus, it is recommended as an add‐on to regular asthma therapy for adults with controlled or partially controlled HDM‐driven allergic asthma (conditional recommendation, moderate‐quality evidence). HDM SCIT is recommended for adults and children, and SLIT drops are recommended for children with controlled HDM‐driven allergic asthma as the add‐on to regular asthma therapy to decrease symptoms and medication needs (conditional recommendation, low‐quality evidence).  相似文献   
107.
Inflammation, structural, and functional abnormalities within the airways are key features of asthma. Although these processes are well documented, their expression varies across the heterogeneous spectrum of asthma. Type 2 inflammatory responses are characterized by increased levels of eosinophils, FeNO, and type 2 cytokines in blood and/or airways. Presently, type 2 asthma is the best‐defined endotype, typically found in patients with allergic asthma, but surprisingly also in nonallergic patients with (severe) asthma. The etiology of asthma with non‐type 2 inflammation is less clear. During the past decade, targeted therapies, including biologicals and small molecules, have been increasingly integrated into treatment strategies of severe asthma. These treatments block specific inflammatory pathways or single mediators. Single or composite biomarkers help to identify patients who will benefit from these treatments. So far, only a few inflammatory biomarkers have been validated for clinical application. The European Academy of Allergy & Clinical Immunology Task Force on Biomarkers in Asthma was initiated to review different biomarker sampling methods and to investigate clinical applicability of new and existing inflammatory biomarkers (point‐of‐care) to support diagnosis, targeted treatment, and monitoring of severe asthma. Subsequently, we discuss existing and novel targeted therapies for asthma as well as applicable biomarkers.  相似文献   
108.
BACKGROUND: Rhinitis symptoms among bell pepper greenhouse employees can be caused by an allergy to occupational allergens, such as bell pepper pollen and predatory mites, and common inhalant allergens. OBJECTIVES: To estimate the effect of sensitization to these allergens on rhinitis-specific quality of life (QoL) during and outside the flowering period and to evaluate whether the QoL of sensitized employees is comparable with that of chrysanthemum greenhouse employees with rhinitis and an average population sample with perennial rhinitis. METHODS: We invited 233 employees with rhinitis symptoms to complete 2 rhinitis QoL questionnaires and to undergo skin prick testing with common inhalant allergens and occupational allergen extracts. Multiple regression analysis was used to estimate the impact of sensitization to the various allergens on QoL. RESULTS: Sensitization to bell pepper pollen had a significant negative effect on all the domain and mean QoL scores. The other allergens had no effect on QoL. A significant decrease in all the rhinitis scores was found outside the flowering period. There were no relevant differences in the mean scores of the different domains for both occupational groups. Greenhouse employees scored higher on limitations in activities and much lower on emotional, sleeping, and practical problems compared with individuals with perennial rhinitis. CONCLUSIONS: Bell pepper greenhouse employees are impaired in QoL because of their sensitization to bell pepper pollen, suggesting that bell pepper pollen is the most important occupational allergen in greenhouse workers with allergic symptoms. A common allergy does not have more impact on a person's day-to-day life than an occupational allergy; however, there is a clear difference in the way in which an occupational group is hampered compared with a nonoccupational group.  相似文献   
109.
Background Adherence is essential for effective treatment. Although several trials on the efficacy of sublingual immunotherapy (SLIT) in youngsters have been published, few contain data on medication intake. Objective We aimed to quantify adherence both to study protocol and medication intake as well as to identify factors that may influence adherence to SLIT in youngsters with rhinoconjunctivitis. Methods Two hundred and four youngsters (6–18 years) with hayfever participated in a randomized controlled trial and used grass pollen extract or placebo for 2 years. The primary outcome of the trial was the mean daily total rhinoconjunctivitis symptom score in the second grass pollen season. Participants having completed the follow‐up were considered adherent to the study protocol. Adherence to medication intake was assessed by weighing the study medication. Participants who completed the follow‐up and used 80% of the prescribed medication were considered adherent to medication intake. Patient‐, disease‐ and treatment‐related factors were analysed. Results One hundred and fifty‐four youngsters completed the study. The main reason for discontinuation was the inability to take medication according to schedule. Drop‐outs were older, had more difficulty following the medication instructions and their overall evaluation of the treatment effect was lower. The number and reasons for drop‐out did not differ between treatment groups. In total, 77% of the participants was adherent to medication intake. Self‐reported adherence was 99%. Non‐adherent participants experienced more severe symptoms before the trial. Symptom scores did not differ between adherent and non‐adherent participants. In adherent as well as non‐adherent participants, no difference was found between verum and placebo group with respect to symptom scores. Conclusion Adherence to both study protocol and medication intake was good. Drop‐out was affected by age, evaluation of the treatment effect and medication instructions. Non‐adherence to medication intake was influenced by the severity of the disease before the trial. The ineffectiveness of SLIT could not be explained by non‐adherence.  相似文献   
110.
OBJECTIVE: The essential amino acid L-methionine is a potential compound in the prophylaxis of recurrent or relapsing urinary tract infection due to acidification of urine. As an intermediate of L-methionine metabolism, homocysteine is formed. The objective was to study the metabolism of L-methionine and homocysteine, and to assess whether there are differences between patients with chronic urinary tract infection and healthy control subjects. DESIGN: A randomized placebo-controlled double-blind intervention study with cross-over design. SETTING: Department of Nutritional Physiology, Institute of Nutrition in cooperation with the Department of Internal Medicine III, Friedrich Schiller University of Jena, Germany. SUBJECTS: Eight female patients with chronic urinary tract infection and 12 healthy women (controls). INTERVENTIONS: After a methionine-loading test, the volunteers received 500 mg L-methionine or a placebo three times daily for 4 weeks.Main outcome measures:Serum and urinary concentrations of methionine, homocysteine, cystathionine, cystine, serine, glycine and serum concentrations of vitamin B12, B6 and the state of folate. RESULTS: Homocysteine plasma concentrations increased from 9.4+/-2.7 micromol/l (patients) and 8.9+/-1.8 micromol/l (controls) in the placebo period to 11.2+/-4.1 micromol/l (P=0.031) and 11.0+/-2.3 micromol/l (P=0.000), respectively, during L-methionine supplementation. There were significant increases in serum methionine (53.6+/-22.0 micromol/l; P=0.003; n=20) and cystathionine (0.62+/-0.30 micromol/l; P=0.000; n=20) concentrations compared with the placebo period (33.0+/-12.0 and 0.30+/-0.10 micromol/l; n=20). Simultaneously, renal excretion of methionine and homocysteine was significantly higher during L-methionine intake. CONCLUSIONS: Despite an adequate vitamin status, the supplementation of 1500 mg of L-methionine daily significantly increases homocysteine plasma concentrations by an average of 2.0 micromol/l in patients and in control subjects. An optimal vitamin supplementation, especially with folate, might prevent such an increase.  相似文献   
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