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2.
Empty Sella and Headache   总被引:2,自引:0,他引:2  
SYNOPSIS
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology.  相似文献   
3.
We have investigated the use of a cationic lipid preparation to enhance antisense oligonucleotide activity in human umbilical vein endothelial cells. A liposomal preparation containing the cationic lipid N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA) was found to increase by at least 1000-fold the potency of an antisense oligonucleotide (ISIS 1570) that hybridizes to the AUG translation initiation codon of human intercellular adhesion molecule-1. In the presence of 8 microM DOTMA, 6-15-fold more 35S-ISIS 1570 associated with cells, at oligonucleotide concentrations from 0.01 to 5 microM, than did in the absence of DOTMA. Both 35S-ISIS 1570 association with cells and antisense activity were increased as a function of DOTMA concentration and with increasing time of incubation with the cationic lipid. Fluorescein-labeled ISIS 1570 was used to assess the intracellular distribution of the oligonucleotide in the presence and absence of DOTMA. In the absence of DOTMA, the oligonucleotide localized to discrete structures in the cytoplasm of the cell, resulting in a punctate fluorescence pattern. In the presence of DOTMA, cellular fluorescence markedly increased and the oligonucleotide localized within the nucleus, as well as to discrete structures in the cytoplasm. Accumulation of the oligonucleotide in the nucleus in the presence of DOTMA was time and temperature dependent. Nuclear accumulation was inhibited by preincubation of the cells with monensin but not chloroquine, NH4Cl, nocodazole, colcemid, or brefeldin A. These data demonstrate that cationic lipids increase antisense activity by increasing the amount of oligonucleotide associated with cells and altering intracellular distribution of the oligonucleotide.  相似文献   
4.
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%.  相似文献   
5.
OBJECTIVE: Epilepsy with mutation of the CDKL5 gene causes early seizures and is a variant of Rett syndrome (MIM (312750), which is reported typically as infantile spasms. The purpose of this study was to analyze the epileptic histories and EEGs of patients with the CDKL5 mutation. METHODS: We reviewed the epilepsy histories and electroclinical analyses of three girls aged 9.5, 7.4, and 9.4 years, each with a mutation of the CDKL5 gene. RESULTS: We revealed the presence of an encephalopathy that started by 1.5 months of age. At first, seizures involved tonic spasms or complex partial seizures, and were complicated by the later appearance of complex partial, tonic, and unexpectedly, myoclonic seizures. This form of epilepsy was drug resistant. Routine and prolonged video EEGs both displayed a homogeneous electroclinical pattern consisting of (a) unique background with diffuse high voltage sharp waves of 6-7 Hz, and absence of the typical rhythmic frontal-central theta activity present in Rett syndrome; (b) unique awake and sleep background, with diffuse, high voltage, continuous sharp waves with multifocal and diffuse spikes; (c) rhythmic, diffuse, 15 Hz activity accompanied clinically by tonic seizures; (d) intercritical pattern with pseudoperiodic, diffuse, sharp waves or pseudoperiodic, diffuse spike and polyspike or wave discharges; and (e) diffuse, spike, polyspike and wave discharges accompanied by massive or focal myoclonias or both. CONCLUSIONS: Patients with the CDKL5 mutation have an early onset, epileptic encephalopathy in infancy that evolves into myoclonic seizures in childhood with a unique EEG pattern. SIGNIFICANCE: Recognizing this type of encephalopathy could be useful in prompting clinicians to proceed further with their diagnostic work in patients not fitting the criteria of classical Rett syndrome.  相似文献   
6.
The relationships between gastric pH and Helicobacter pylori infection were studied in 37 consecutive subjects affected with nonulcer dyspepsia. Each underwent esophagogastroduodenoscopy with multiple gastric biopsies for both H. pylori and histologic assessment, and 24-hr antral pH monitoring. H. pylori was harbored by 59.5% of the subjects with whole gastric spread of infection in all but one patient. Histologic gastritis was shown in 70.3% of the subjects. H. pylori was strongly associated with gastritis, both antral nonatrophic and multifocal atrophic. The ranges of 24-hr pH values were 1.3-6.9 in the H. pylori-positive and 1.2-6.8 in the H. pylori-negative group. Differences in pH values between the two groups were not significant. Moreover, the mean percent time duration of pH above 2, 4, and 6 did not significantly differ between the two groups. Therefore, this study has shown that chronic H. pylori infection is not related to luminal gastric pH.  相似文献   
7.
OBJECTIVE: The present study tested the hypothesis that the serum copper abnormalities were correlated with alterations of resting electroencephalographic (EEG) rhythms across the continuum of healthy elderly (Hold), mild cognitive impairment (MCI), and AD subjects. METHODS: Resting eyes-closed EEG rhythms delta (2-4Hz), theta (4-8Hz), alpha 1 (8-10.5Hz), alpha 2 (10.5-13Hz), beta 1 (13-20Hz), beta 2 (20-30Hz), and gamma (30-40Hz), estimated by LORETA, were recorded in 17 Hold, 19 MCI, 27 AD- (MMSE< or =20), and 27 AD+ (MMSE20) individuals and correlated with copper biological variables. RESULTS: Across the continuum of Hold, MCI and AD subjects, alpha sources in parietal, occipital, and temporal areas were decreased, while the magnitude of the delta and theta EEG sources in parietal, occipital, and temporal areas was increased. The fraction of serum copper unbound to ceruloplasmin positively correlated with temporal and frontal delta sources, regardless of the effects of age, gender, and education. CONCLUSIONS: These results sustain the hypothesis of a toxic component of serum copper that is correlated with functional loss of AD, as revealed by EEG indexes. SIGNIFICANCE: The present study represents the first demonstration that the fraction of serum copper unbound to ceruloplasmin is correlated with cortical delta rhythms across Hold, MCI, and AD subjects, thus unveiling possible relationships among the biological parameter, advanced neurodegenerative processes, and synchronization mechanisms regulating the relative amplitude of selective EEG rhythms.  相似文献   
8.
We have employed an in vitro system to study transport and metabolism of organic molecules by gastrointestinal tissues. Such a system would aid in the evaluation of the potential for oral delivery of organic molecules. Transport and metabolism of 5-fluorouracil (5-FU) were studied using rabbit intestinal preparations. Unidirectional fluxes and metabolism were measured in vitro in Ussing chambers under short-circuit conditions. Results from these studies reveal that in ileum, proximal, and distal colon, steady-state fluxes of 5-FU (10 µM added to both bathing solutions) are established after 30 min and remain constant for at least 110 min. Transport of 5-FU under sink conditions with 10 µM 5-FU present in the mucosal or serosal bathing solution alone demonstrated similar rates of transport as under nonsink conditions. The concentration dependence of 5-FU fluxes indicates that the mucosal (m)-to-serosal (s) flux is composed of both a saturable and a linear component over the range of 1–100 µM in the ileum, whereas the s-to-m flux in the ileum and both fluxes in the colon are linear functions of concentration. Over the concentration range employed and the time course of these studies, 5-FU had no effect on the electrical properties of the ileum or colon. In the ileum, the m-to-s but not the s-to-m flux of 5-FU was reduced by (1) serosal ouabain (0.1 mM); (2) reduction of the bathing solution Na concentration; and (3) addition of uracil, thy mine, thymidine, uridine, 2-deoxyuridine, or uridine-5-monophosphate. These results indicate that 5-FU absorption in the ileum occurs by a Na-dependent mechanism that is inhibited by uracil and structurally related compounds. In distal colon, no evidence for an active transport mechanism was obtained. High-performance liquid chromatography (HPLC) analysis reveals that both ileum and distal colon metabolize 5-FU to more polar compounds. Metabolism in ileum is quantitatively greater than in distal colon. Metabolites are found predominantly on the side to which transport has occurred, suggesting that metabolism occurs concomitantly with transport. Since the intestinal cells metabolize 5-FU to more polar compounds and active absorption is inhibited in a competitive manner by related compounds, these results may provide an explanation for the variable oral activity reported for 5-FU.  相似文献   
9.
The lactoperoxidase (LPO) antibiotic system is a well-characterized component of mammary and salivary gland secretions. Because LPO has been shown to function in ovine airways, human airway tissue and secretions were examined for the presence of LPO and its substrate, the anion thiocyanate (SCN-). In addition, human airway secretions were tested for LPO-mediated antibacterial activity, and LPO's activity was assessed against some human airway pathogens. The data showed that normal human airway secretions contained LPO enzyme activity (0.65 +/- 0.09 microg/mg secreted protein; n = 17), and Western blots of secretions demonstrated bands of the expected sizes for LPO. LPO mRNA was detected in trachea by sequencing PCR-amplified cDNA. SCN-, LPO's substrate, was present in undiluted airway secretions at concentrations sufficient for LPO catalysis (0.46 +/- 0.19 mM; n = 8), and diluted secretions contained antibacterial activity with LPO-like properties. Immunocytochemistry localized LPO to submucosal glands in human bronchi. Finally, as expected based on the known antibacterial spectrum of the LPO system, airway secretions showed LPO-dependent activity against Pseudomonas aeruginosa. In addition, the airway LPO system was shown to be effective against Burkholderia cepacia and Haemophilus influenzae. Thus, a functional LPO system exists in human airways and may contribute to airway host defense against infection.  相似文献   
10.
Increased risk of Alzheimer's disease (AD) has been associated with polymorphisms in the IL-1 gene cluster, and in particular with the IL-1alpha-889 T/T genotype. However, this association is still unclear, and needs further investigation. In order to clarify the role of these polymorphisms in the complex pathogenesis of AD we examined genotype and haplotype frequencies of the two C-to-T SNPs at position -889 and -551 in the IL-1alpha and IL-1beta genes, respectively, and of the 86 bp VNTR intron-2 polymorphisms in the IL-1Ra gene. The analysis was performed in two genetically and diagnostically distinct groups of sporadic AD from Italy and the USA. In the Italian group a significant association between the IL-1alpha-889 T/T genotype and AD (OR=3.022, 95% CI: 1.001-9.119) was found, whereas no difference was found in the group from the USA. Results were also compared with previously published studies that analyzed the same IL-1 polymorphisms in AD. In both groups, the analysis of the estimated haplotypes shows that AD patients and controls who carry the IL-1beta-511 C allele, were also more frequently carriers of the IL-1Ra 1 allele (haplotypes -C-1). The total frequency of the two -C-1 haplotypes (C-C-1 plus T-C-1) was about one half of the total frequency of the eight estimated haplotypes. This was confirmed by significant linkage disequilibrium between these two loci in both the Italian and USA groups. In the Italian group a weak association of the T-C-2 haplotype with the disease (OR=1.648, 95% CI: 1.519-1.788) was also found, whereas in the USA group no difference was found. Although ours and other published data on different samples of Caucasian and non-Caucasian AD show a great heterogeneity in the frequencies of the IL-1alpha-889, the IL-1beta-511 and the IL-1Ra VNTR gene polymorphisms, we confirm the role of the IL-1alpha-889 T/T genotype as a risk factor for sporadic AD, and show the presence of an allelic association between IL-1beta C and IL-1Ra 1 alleles in both the Italian and the USA groups, confirmed by the presence of significant levels of linkage disequilibrium between these two loci.  相似文献   
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