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91.
Somatoform pain disorder in the general population   总被引:6,自引:0,他引:6  
BACKGROUND: Chronic pain disorder is assumed to represent a frequent and disabling condition. However, data on the prevalence of somatoform pain symptoms and somatoform pain disorder in the community are limited to date. METHODS: German versions of the Composite International Diagnostic Interview were administered to a representative national sample of 4,075 people. Somatoform pain disorder was diagnosed by standardized diagnostic algorithm based on the DSM-III-R criteria (absence of adequate physical findings). One subgroup was identified as also meeting the DSM-IV criterion B for 'significant distress or psychosocial impairment due to the somatoform pain'. RESULTS: A lifetime prevalence rate of somatoform pain disorder according to DSM-III-R of 33.7% and a 6-month rate of 17.3% was found. When applying the DSM-IV B criterion, the prevalence rate dropped to 12.3 and 5.4%, respectively. In both groups more than 95% of the probands had contacted their doctor because of the pain. In 25% of the probands the pain was positively assigned to psychological factors. A female:male ratio of 2:1 was found. CONCLUSIONS: Somatoform pain disorder (DSM-III-R) is a frequent condition. However, only about one third of these subjects is severely distressed or impaired by the pain. A clear operationalized concept of the DSM-IV criterion C 'psychological factors are judged to have an important role in the onset, severity, exacerbation or maintenance of the pain' should be provided in the further development of the diagnosis 'pain disorder' in order to make this diagnosis suitable for general population surveys.  相似文献   
92.
Summary: Using extensive Molecular Dynamics simulations we study the behavior of very rigid polyelectrolytes with hydrophobic side chains that are known to form cylindrical micelles in aqueous solution. We investigate the stability of such micelles with respect to hydrophobicity, Coulomb interaction, and micellar size. We show that for the parameter range relevant for poly(p‐phenylene sulfonate)s (PPP) one finds a stable finite micellar size close to the experimental parameter region. We also point out that our model has some similarities to DNA solutions with added condensing agents, hinting to the possibility that the size of DNA aggregates is under certain circumstances thermodynamically limited.

DNA‐like morphologies of the polyelectrolytes.  相似文献   

93.
Aerobic microorganisms were isolated and identified from 9 of 10 malignant tissues aseptically obtained from surgical patients. The organisms isolated are species commonly associated with the flora of the human body. When these cancer-associated organisms were grown in Trypticase soy broth (BBL Microbiology Systems), a protein substance was isolated from the culture filtrates by acetone precipitation. The acetone precipitates of 12 of 14 organisms tested were positive when assayed by radioimmunoassay for the beta subunit of human chorionic gonadotropin (hCG). All but one of the bacterial isolates from the malignancies were capable of producing the hCG-like substance, but in varying quantities. Control organisms (not isolated from a malignancy) and uninoculated Trypticase soy broth were either completely negative in the radioimmunoassay for beta hCG or had levels of beta hCG near the limit of the sensitivity of the method. These results suggest the possibility that bacteria-tumor relationships do exist and are in agreement with the findings of other workers. Investigation of these relationships may have important and provocative implications in the study of neoplastic diseases.  相似文献   
94.
Summary The ascomycete fungus Ascochyta rabiei, an important pathogen of the grain legume crop chickpea (Cicer arietinum L.) in the Mediterranean region, has not been adequately characterized in molecular terms. We therefore used DNA fingerprinting, with synthetic oligodeoxynucleotides complementary to simple repetitive sequences, to pathotype different isolates of the fungus. Six single-spored A. rabiei isolates were first categorized using a host differential set of nine chickpea genotypes. Seedlings were inoculated under controlled environmental conditions, and disease severity was recorded 9 days after inoculation. DNA was extracted from in vitro-grown mycelia of the six purified fungal isolates, restricted with EcoRI, HinfI, MboII and TaqI, and fingerprinted with radiolabeled (GATA)4, (GTG)5, (CA)8, and (TCC)5, respectively. High levels of polymorphism were detected with optimal enzyme/probe combinations that allow one to discriminate between the isolates. The potential of DNA fingerprinting with simple repetitive sequences can thus be expanded to the identification of fungal races and pathotypes. The characterization of the geographic distribution and genetic variability of pathotypes will facilitate the selection of suitable host cultivars to be grown in specific regions.  相似文献   
95.
96.

Introduction

The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.

Design

FFPE-derived RNA from sections of 23 patients with spontaneous pneumothoraxes was used. Unstained sections of FFPE tissue were stored at various temperatures (?80?°C, ?20?°C, 4?°C, 24?°C) prior to RNA extraction. The potential impact on RNA quality of semi-automatic and manual RNA isolation and three different deparaffinization agents (mineral oil, xylene and d-limonene) were compared.

Results

The storage temperature of FFPE sections affects RNA concentration and fragmentation, with the optimal storage temperature below -20?°C. The RNA extracted with d-limonene shows equivalent quality to the RNA extracted using more toxic standard agents. The manual isolation provides a higher RNA yield compared to the semi-automatic isolation. However, no differences in the amount of longer RNA fragments were observed. Furthermore, the semi-automatic isolation showed an enhanced RNA quality.

Conclusion

FFPE sections not directly used for RNA extraction should be stored below -20?°C to increase quality and yield of the RNA. Usage of semi-automatic isolation produces superior results and simplifies routine processes by having less hands-on-time. Replacement of toxic xylene by d-limonene may contribute to improved occupational safety while not influencing analytical results.  相似文献   
97.
Various procedures were used to derive continuously growing cytotoxic T lymphocyte (CTL) clones from a primary culture containing responder cells from immunized mice and 3-(p-sulfophenyldiazo)-4-hydroxylphenyl acetic acid (SP)-or fluorescein isothiocyanate (FL)-coupled stimulator cells. It seems likely that CTL have to undergo some change, possibly genetic, to be able to grow continuously in T cell growth factor conditioned medium in the absence of any stimulator or filler cells. The most convenient and reliable procedure to generate CTL clones with different specificities was to establish from several aliquots of a primary culture cell populations continuously growing in medium conditioned with T cell growth factor(s). Clones with different specificities segregated in the different populations. SP-and FL-specific CTL clones restricted to H-2Kk, and H-2Dd and two FL-specific CTL clones with no apparent H-2 restriction are described.  相似文献   
98.
We examined 26 individuals with clinical and electron microscopic signs of late infantile neuronal ceroid lipofuscinosis (LINCL). In 22 cases, we found both pathogenic alleles. Sixteen patients exclusively carried either one or a combination of the two common mutations R208X and IVS5-1G > C. In the remaining cases, four missense mutations could be detected, of which R127Q, N286S, and T353P represent novel, previously not described alleles. A clinical performance score was developed by rating motor, visual, and verbal functions and the incidence of cerebral seizures in 3-month intervals during the course of the disease. A Total Disability Score was derived by summing up the single scores for motor, visual, and verbal functions. The 16 individuals with the two common mutations were grouped together (referred to as standard patients), and the 5th, 50th, and 95th centiles were calculated and graphically depicted over time. The scores for motor function and language ability dropped earliest and progressed very similarly in the standard patients. The performance curves of two children with the N286S mutation slightly diverged from the 95th centile. However, the performance curves of one patient with atypical LINCL carrying the R127Q mutation fell far beyond the 95th centile. The presented performance rating clearly and quantitatively delineates the disease course of the LINCL patients and hence offers a useful tool for clinical evaluation of future therapeutic interventions. In addition, the described performance score system can be applied to other types of neuronal ceroid lipofuscinoses and could be adapted to various other neurodegenerative diseases of childhood.  相似文献   
99.
Recent event-related potential (ERP) studies revealed the selective processing of affective pictures. The present study explored whether the same phenomenon can be observed when pictures are presented only briefly. Toward this end, pleasant, neutral, and unpleasant pictures from the International Affective Pictures Series were presented for 120 ms while event related potentials were measured by dense sensor arrays. As observed for longer picture presentations, brief affective pictures were selectively processed. Specifically, pleasant and unpleasant pictures were associated with an early endogenous negative shift over temporo-occipital sensors compared to neutral images. In addition, affective pictures elicited enlarged late positive potentials over centro-parietal sensor sites relative to neutral images. These data suggest that a quick glimpse of emotionally relevant stimuli appears sufficient to tune the brain for selective perceptual processing.  相似文献   
100.
We report on the development of a fully automated real-time PCR assay for the quantitative detection of hepatitis B virus (HBV) DNA in plasma with EDTA (EDTA plasma). The MagNA Pure LC instrument was used for automated DNA purification and automated preparation of PCR mixtures. Real-time PCR was performed on the LightCycler instrument. An internal amplification control was devised as a PCR competitor and was introduced into the assay at the stage of DNA purification to permit monitoring for sample adequacy. The detection limit of the assay was found to be 200 HBV DNA copies/ml, with a linear dynamic range of 8 orders of magnitude. When samples from the European Union Quality Control Concerted Action HBV Proficiency Panel 1999 were examined, the results were found to be in acceptable agreement with the HBV DNA concentrations of the panel members. In a clinical laboratory evaluation of 123 EDTA plasma samples, a significant correlation was found with the results obtained by the Roche HBV Monitor test on the Cobas Amplicor analyzer within the dynamic range of that system. In conclusion, the newly developed assay has a markedly reduced hands-on time, permits monitoring for sample adequacy, and is suitable for the quantitative detection of HBV DNA in plasma in a routine clinical laboratory.  相似文献   
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