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11.
Depression-executive dysfunction syndrome in stroke patients.   总被引:6,自引:0,他引:6  
OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. Methods: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options.  相似文献   
12.

Background  

Movement control dysfunction [MCD] reduces active control of movements. Patients with MCD might form an important subgroup among patients with non specific low back pain. The diagnosis is based on the observation of active movements. Although widely used clinically, only a few studies have been performed to determine the test reliability. The aim of this study was to determine the inter- and intra-observer reliability of movement control dysfunction tests of the lumbar spine.  相似文献   
13.
14.
A novel chemical etching method was recently developed to create a controlled microrough surface on porous bioactive glass implants. Our earlier in vitro studies showed enhanced attachment of osteoblast-like MG63 cells on a microrough bioactive glass surface. The purpose of our current study was to confirm the in vivo significance of surface microroughening for bone bonding of bioactive glass. Porous bioactive glass cones made of sintered microspheres were surgically implanted in the anterior cortex of rabbit femurs. Peripheral quantitative computed tomography (pQCT), biomechanical push-out testing, histomorphometry, and electron microscopy (BEI-SEM) were used to analyze bone ingrowth and osseointegration at 7, 10, 14, 28, 56, and 84 days after implantation. The results showed that microroughening of the bioactive glass surface significantly enhanced the bone-bonding response of the biomaterial. The positive response was seen in one of the three bioactive glass compositions studied. The affinity index of new bone on the glass surface was significantly (p = 0.02) increased with a trend (p = 0.10) toward improved mechanical incorporation. New bone formation was dependent on the glass composition, and it was found to occur not only through the mechanism of bone ingrowth but also based on in situ osteogenesis within implant interstices. Based on these results, the procedure of microroughening could enhance the osteopromotive properties of certain bioactive glass compositions.  相似文献   
15.
Chromosome aberrations (CA), micronuclei (MN, cytokinesis-block [CB] method), and sister-chromatid exchanges (SCE) were analysed in blood lymphocytes of 17 workers and 17 control subjects. The mean urinary mandelic acid level (average 9.4 mmol/l) and styrene glycol in blood (average 2.5 mumol/l) implied exposure to about 300 mg/m3 of styrene in the plant. The number of CA was significantly higher in non-smoking workers compared with nonsmoking controls. A significant correlation was observed between duration of exposure and individual CA level of all workers. No significant effects were observed in MN or SCE. Single-strand breaks (SSB) in DNA of isolated lymphocytes were studied in nine of the workers and eight of the controls by the DNA-unwinding technique. The results showed an increase in SSB among the exposed workers. The present findings support earlier reports on the increase of structural CA in blood lymphocytes of workers in the reinforced plastic industry, and also show that SSBs are elevated in such workers.  相似文献   
16.
The intermediate filament proteins nestin, vimentin, and desmin show a specific temporal expression pattern during the development of myofibers from myogenic precursor cells. Nestin and vimentin are actively expressed during early developmental stages to be later down-regulated, vimentin completely and nestin to minimal levels, whereas desmin expression begins later and is maintained in mature myofibers, in which desmin participates in maintaining structural integrity. In this study we have analyzed the expression levels and distribution pattern of nestin in intact and denervated muscle in rat and in human. Nestin immunoreactivity was specifically and focally localized in the sarcoplasm underneath neuromuscular junctions (NMJs) and in the vicinity of the myotendinous junctions (MTJs), ie, in regions associated with acetylcholine receptors (AChRs). This association prompted us to analyze nestin in neurogenically and myogenically denervated muscle. Immunoblot analysis disclosed a marked overall increase of accumulated nestin protein. Similar to the extrajunctional redistribution of AChRs in denervated myofibers, nestin immunoreactivity extended widely beyond the NMJ region. Re-innervation caused complete reversion of these changes. Our study demonstrates that the expression levels and distribution pattern of nestin are regulated by innervation, ie, signal transduction into myofibers.  相似文献   
17.
Both [Leu5]- and [Met5]-enkephalin have been localized immunohistochemically in nerve fibres and in small, intensely fluorescent cells of adult human sympathetic ganglia. The nerve fibres showing enkephalin-like immunoreactivity formed a network varying in density around the sympathetic neurons, some being closely related to the perikarya. No labelled neuronal cell bodies were found. No structures within the ganglion were labelled after reaction with antibodies to vasoactive intestinal polypeptide, adrenocorticotrophin or substance P. No differences between the distributions of [Leu5]-and [Met5]-enkephalin-like immunoreactivities were found.The physiological roles of enkephalins are still unknown, but it is possible that they might act as neurotransmitters or neuromodulators in the human sympathetic nervous system.  相似文献   
18.
Glial-cell-line-derived neurotrophic factor (GDNF) is a distant member of the transforming growth factor superfamily. It binds to and activates a receptor complex consisting of GFR-alpha1 and Ret receptor tyrosine kinase. In testis, GDNF is expressed by Sertoli cells. We have shown by transgenic loss- and gain-of-function mouse models that GDNF regulates the cell fate decision of undifferentiated spermatogonia. In the GDNF +/- mice, the spermatogonia differentiate in excess leading to the depletion of germ cells. In the mice overexpressing GDNF in testes, undifferentiated spermatogonia accumulate in the tubules, no sperm is produced, and the mice are infertile. After a year, the GDNF overexpressing mice frequently (89%) develop testicular tumours, and most of them are bilateral (56%). All these tumours show the same histological pattern. They are composed of round spermatogonial/gonocytic cells with only a scant cytoplasm. The tumours are locally invasive but do not metastasise. They express germ line markers, are positive for alkaline phosphatase, and aneuploid with a triploid peak. Thus, by several histological, molecular, and histochemical characteristics, the GDNF-induced tumours mimic classical seminomas in men, but the precursor lesions are apparently different in mouse and man.  相似文献   
19.
Summary World Health Organization's goal Health for All is the starting point for a most ambitious health policy ever. The paper analyzes the role of epidemiology in the Organization's work, particularly in the Health for All development. During WHO's early years, epidemiology helped to design and carry out major public health campaigns against such scourges of the humanity as yaws, tuberculosis, malaria and small pox. When the Organization during the 1960s began to emphasize the need to develop the infrastructure of health care, health services research partly replaced epidemiology as WHO's main scientific allay. After the Health for All policy was launched in 1987, epidemiology has again played a major role in establishing the scientific background of the policy. The European experiences show how the epidemiologists can help WHO to identify the most important health problems and set achievable and measurable targets for them. The paper concludes that epidemiology serves to identify problems, show ways to solve them, monitor the changes in the situation and evaluate the achievements.
Zusammenfassung Das Ziel der Weltgesundheitsorganisation Gesundheit für alle ist Ausgangspunkt für die ehrgeizigste Gesundheitspolitik, die je definiert wurde. Der vorliegende Artikel analysiert die Rolle der Epidemiologie in der Arbeit der Organisation, insbesondere bei der Entwicklung von Gesundheit für alle. Während der frühen Jahre der WHO half die Epidemiologie bei der Planung und Ausführung der grossen Gesundheitskampagnen gegen Geisseln der Menschheit wie Frambösie, Tuberkulose, Malaria und Pocken. In den 60er Jahren begann die WHO, die Wichtigkeit der Entwicklung von Infrastrukturen für die Gesundheitsversorgung zu betonen, Gesundheitswesensforschung ersetzte in der Folge teilweise Epidemiologie als wichtigsten wissenschaftlichen Bereich der WHO. Seit 1987 aber Gesundheit für alle in Angriff genommen wurde, spielt die Epidemiologie wieder eine wichtige Rolle in der Erarbeitung des wissenschaftlichen Hintergrundes dieser Politik. Die europäische Erfahrung zeigt, wie Epidemiologen der WHO helfen können, die wichtigsten Gesundheitsprobleme zu erkennen und erreichbare und messbare Ziele für sie zu setzen. Der vorliegende Artikel schliesst, dass die Epidemiologie dazu dient, Gesundheitsprobleme zu identifizieren, Wege aufzuzeigen, wie sie zu lösen sind, Änderungen der Situation zu überwachen und die Erfolge zu evaluieren.

Résumé Pour l'OMS (Organisation mondiale de la santé), le programme «Santé pour tous» doit être le point de départ d'une action de santé sans précédent. Cet article analyse le rôle de l'épidémiologie à l'OMS, en particulier dans le cadre de ce programme. Au début de l'existence de l'OMS l'épidémiologie a permis de planifier et de conduire les grandes campagnes contre des maladies telles que la tuberculose, la malaria et la variole. Dans les années 60, l'OMS a insisté sur le développement de l'infrastructure des soins, la recherche sur les services de santé remplaçant en partie le rôle conducteur de l'épidémiologie. Avec le lancement du programme «Santé pour tous» en 1987, l'épidémiologie joue à nouveau un rôle central pour fonder le programme scientifique de l'OMS. L'expérience européenne montre de quelle façon les épidémiologistes peuvent aider l'OMS pour identifier les problèmes les plus importants et établir des buts raisonnables et mesurables. L'article montre comment l'épidémiologie sert à identifier les problèmes, établir des façons de les résoudre et évaluer l'impact de ces programmes.
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20.
OBJECTIVE: To present the clinical, neuroimaging, and electrophysiologic characteristics of a variant AD phenotype. BACKGROUND: The authors have identified a large Finnish kindred with presenile dementia and spastic paraparesis due to deletion of exon 9 of presenilin 1. Neuropathologic analysis showed unusual cortical "cotton wool" plaques, immunoreactive for the beta-amyloid peptide but lacking congophilic cores. PATIENTS AND METHODS: Twenty-two affected individuals (16 men and 6 women) were identified in four successive generations. All surviving five patients were examined and subjected to molecular genetic analysis. In addition, the neurologic records of nine deceased patients were evaluated. Electrophysiologic investigations were available in eight cases. CT or MRI of the head had been performed on 11 patients and PET was performed on three patients. RESULT: The mean age at onset (+/-SD) was 50.9 +/- 5.2 years (range 40 to 61 years). Memory impairment was present in all patients. Memory impairment appeared simultaneously with or was preceded by walking difficulty due to spasticity of the lower extremities (10/14). Impaired fine coordination of hands (9/14) and dysarthria (6/14) in some patients suggested cerebellar involvement. EEG showed intermittent generalized delta-theta activity. Head MRI showed temporal and hippocampal atrophy; PET showed bilateral temporo-parietal hypometabolism. CONCLUSION: Spastic paraparesis or brisk stretch reflexes of lower extremities or clumsiness of hands combined with dementia suggests this variant of AD.  相似文献   
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