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991.
Using a unique measure of unmet need that taps into several dimensions of informal long-term care, the present study included data from 694 informal caregivers of persons suffering from dementia at different times in the caregiving career (e.g., at home, following institutionalization, following the death of the care recipient). Multivariate regression models found that unmet need for either confidante or formal support had key implications for caregivers' emotional distress in each of the care situations. The findings suggest that conceptual models should incorporate unmet need as a viable predictor of caregiving outcomes and that assessment of unmet need may provide guidance in the development of more refined psychosocial and community-based intervention protocols.  相似文献   
992.
DNA microarray technology is based on the principle of hybridization between 2 complementary strands of nucleic acids, one being fixed into a solid membrane, the other being the sample to analyze. This has resulted in a very powerful method to examine differential gene expression between samples, and has been widely used in the study of tumors. The application of DNA microarray technology to the study of the nervous system has to consider several properties of the nervous tissue: composition of various neuronal types, as well as astrocytes, oligodendrocytes, and microglia; regional and area differences; developmental and age-dependent variations; and functional and pathological status. Moreover, human samples are usually obtained postmortem following variable agonal periods and postmortem delays between death and tissue preservation, which are accompanied by variable RNA degradation. Yet human postmortem nervous tissue stored in brain banks offers a unique opportunity to facilitate material for the study of diseases of the nervous system and to gain direct understanding on the mechanisms of disease. This review analyzes the application of DNA microarray technology to current practice using brain-banked tissues in order to recognize and minimize sub-optimal processing of brain samples and to correct pitfalls due to inadequate procedures. Also discussed are RNA preservation and RNA degradation effects on expression pattern assessments, analysis of individual versus pooled samples, array normalization, types of DNA chip platforms, whole genomic analysis versus specialized chips, and microgenomics. Minimizing RNA degradation and improving detection of resistant RNA in postmortem brain has been considered in detail in order to improve the efficiency and reliability of DNA microarray technology employed in the study of human postmortem nervous tissue.  相似文献   
993.
Chlorpromazine (CPZ) is concentrated by human macrophages where it kills intracellular mycobacteria when the concentration outside the macrophage is sub-clinical. We have previously demonstrated that thioridazine (TZ), a much milder phenothiazine, has similar activity and kills intracellular methicillin-susceptible S. aureus at sub-clinical concentrations. We have extended this latter study to include methicillin-resistant S. aureus (MRSA) and show that TZ kills intracellular MRSA at clinically relevant concentrations. The ultrastructure of MRSA exposed to in vitro concentrations of TZ just below its MIC and that of MRSA phagocytosed by macrophages previously exposed to a clinically relevant concentration of TZ was also studied. TZ inhibits the replication of phagocytosed MRSA, affecting the structure of the cell envelope, resulting in lysis of the bacterium 6 hours post-phagocytosis. These ultrastructural changes are identical to those produced in vitro by a TZ concentration that is just below the MIC. Because macrophage intracellular MRSA is not killed by the macrophage and its intracellular location protects it from antibiotics that are unable to reach that site, recurrent infections which result may be successfully managed with the use of TZ.  相似文献   
994.
995.
Eyelid bleeding and atypical amyloidosis   总被引:1,自引:0,他引:1  
PURPOSE: To describe a case of atypical systemic amyloidosis in a patient who presented with recurrent subcutaneous bleeding of the eyelids and auricles. DESIGN: Observational case report. METHODS: A 52-year-old man with chronic cardiac failure, hypertension, weight loss, and impotence presented with recurrent bleeding of the eyelids and auricles, and was investigated for suspected amyloidosis. RESULTS: Biopsy specimens taken from the bone marrow, salivary gland, abdominal subcutaneous fat, and gastric mucosa, and eyelids were all negative for Congo red. Results of a conjunctival biopsy, which were returned after the patient's death, and cardiac muscle autopsy were positive for Congo red staining, indicating amyloidosis. CONCLUSION: The findings in this case show that the presentation of amyloidosis may be atypical. Ophthalmologists should consider a diagnosis of amyloidosis in patients with periorbital bleeding, even if biopsies are negative for Congo red. A conjunctival biopsy may be useful in establishing a diagnosis of primary systemic amyloidosis.  相似文献   
996.
PURPOSE: The study reports the results of a histological and ultrastructural examination of the corneal button, obtained during penetrating keratoplasty from patient with clinically recognized macular corneal dystrophy. MATERIAL AND METHODS: 34-year-old male patient suffering from macular corneal dystrophy (MCD) has been treated on corneal epithelium defect and photophobia since his early childhood. Visual acuity was decreased on the Snellen test chart to 0.02. Slit-lamp examination, and ultrasonographical measurement of the cornea's thickness were performed. Removed during penetrating keratoplasty corneal button was divided into two pieces. One of them was prepared in standard procedure for histological examination in the light microscopy after having been stained with hematoxylin and eosin, alcian blue and paS-method. From the other part, slides for ultrastructural examination in the transmission electron microscopy were prepared with the use of standard method. The family history from the patient was also taken, and available relatives have undergone examination in search of typical MCD symptoms. RESULTS: Slit-lamp examination findings revealed diffuse, from limbus to limbus, stromal opacification. In measurement by pachymeter cornea's thickness was reduced. In the light microscopy, in typical stained slides, delaminations within stroma and deficit of endothelial cells were observed. After being stained with alcian blue, dark blue deposits in the places of delamination became visible. By transmission electron microscopic examination, intracellular and extracellular deposits were detected in the stroma, Descemet membrane and endothelium. Distended keratocytes with enormous vacuoles containing abnormal material were found. Pedigree was typical for autosomal recessive inherited disease. CONCLUSIONS: Histological and ultrastructural diagnosis is a basis of recognition of macular corneal dystrophy. Analysis of the pedigree as well as ultrasonographical measurement of the cornea's thickness is very helpful to establish the right diagnosis.  相似文献   
997.
Congenital ectropion uveae is a rare, nonprogressive anomaly characterized by the presence of iris pigment epithelium on the anterior surface of the iris stroma and is occasionally associated with Rieger's anomaly, Prader-Willi syndrome and neurofibromatosis type 1 (NF1). The most important complication of ectropion uveae is congenital or juvenile glaucoma. We described a patient with ectropion and the mutation R1748X in the NF1 gene. This is the third report in the literature describing ectropion associated with neurofibromatosis. If this association is confirmed by other authors, the NF1 patients should be examined for the presence of ectropion and, consequently, for the development of glaucoma.  相似文献   
998.
The attention deficit/hyperactivity disorder (ADHD) can affect human infants and adolescents. One important feature of this disorder is behavioural impulsivity. This study assessed the ability of chronic acetyl-l-carnitine (ALC, saline or 100 mg/kg SC, plus 50 mg/kg orally) to reduce impulsivity in a validated animal model for ADHD. Food-restricted rats were tested during adolescence (postnatal days, pnd, 30–45) in operant chambers with two nose-poking holes, one delivering one food pellet immediately, and the other five pellets after a delay. Delay length was increased over days (from 0 to 80 s). Individual differences in the preference-delay curve emerged, with the identification of two distinct subpopulations, i.e. one with a nearly horizontal curve and another with a very steep (impulsive) slope. The impulsivity profile was slightly but consistently reduced by chronic ALC administration. Consistent results were also obtained with methylphenidate (MPH, saline or 3 mg/kg IP twice daily). Impulsive rats exhibited a lower metabolite/serotonin (5HIAA/5HT) ratio in the medial frontal cortex (MFC) and lower noradrenaline (NA) levels in the MFC and cingulate cortex (CC) when compared with the other subgroup. The ALC treatment increased NA levels in the CC and the 5HIAA/5HT ratio in both CC and MFC. Present data suggest that ALC, a drug devoid of psychostimulant properties, may have some beneficial effects in the treatment of ADHD children.  相似文献   
999.
Aims: The aim of our study was to determine serum levels ofadvanced glycation end-products (AGE) in patients with chronicalcohol misuse and to examine their relationship to markersof nutrition and inflammation. Methods: The study group consistedof 23 heavy alcohol drinkers treated for chronic alcohol misuseand 22 healthy controls. Studied parameters included AGE (fluorescence,CML – carboxymethyllysine and pentosidine), lipids, glucose,albumin, leptin, prealbumin, C-reactive protein (CRP) and pregnancy-associatedplasma protein A (PAPP-A). Results: AGE fluorescence was significantlyhigher in chronic alcoholic patients than in healthy subjects(4.3 ± 0.7 x 103 vs 3.7 ± 0.5 x 103 AU/g protein,P < 0.005), while CML was only slightly but not significantlyelevated (569.1 ± 106.6 vs 545.5 ± 85.8 µg/l)and pentosidine levels did not differ (105.4 ± 29 vs102.2 ± 23 nmol/l). In alcoholics, AGE correlate significantlynegatively with leptin (r = –0.46, P < 0.05) and pentosidinewith prealbumin (r = –0.43, P < 0.05), otherwise therewas no relationship between AGE and other biochemical parameters(glucose, cholesterol, albumin, CRP, PAPP-A). Conclusion: Ourfindings suggest a more complex relationship among advancedglycation, oxidative stress and metabolism of ethanol and theirlink to nutrition and nutrition-associated parameters. AGE asa result of oxidative stress might be similarly linked to increasedcardiovascular risk of heavy alcohol drinkers, as are malnutritionand inflammation; however, further studies are needed to confirmthis hypothesis.  相似文献   
1000.
Four cases of hypereosinophilic syndrome (HES) treated with the tyrosine-kinase inhibitor imatinib-mesylate are reported. The drug was effective in three patients, but a prolonged clinical and hematological remission was obtained only in one patient, due to appearance of resistance or poor tolerability in the other cases. The dose of imatinib necessary to achieve a response ranged from 100 to 600 mg/d. One patient with evidence of a clonal T-cell population did not respond at all. We confirm the efficacy of imatinib in HES, but we also underline that type and duration of response may be variable. This could be due to different pathogenetic mechanisms of the disease in single patients.  相似文献   
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