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991.
Cardiac responses to non-signal stimuli and to signal stimuli in a vigilance task were examined in children born with congenital heart defects (CHD), and in normal and attention deficit disordered (ADD) subjects. Overall task performance was lower in subjects with heart defects and in the ADD group. Cardiac measures revealed that normal children displayed significantly larger heart rate deceleration to the target stimuli than did either of the clinical groups. Moreover, although no group differences were observed in the cardiac response to non-signal auditory stimuli, exaggerated heart rate deceleration was observed to vibrotactile stimuli in both the clinical groups. Regression analyses revealed that the magnitude of the cardiac response to somatosensory stimuli was predictive of task performance (both within and between subject groups), with larger responses associated with higher error rates and lower perceptual sensitivity. Results were suggestive of a predictive relationship between somatosensory reactivity and neuropsychological maturation.  相似文献   
992.
A patient complying with the clinical criteria for brain death was studied by preenhanced computed tomography (CT). Preenhanced CT showed apparent increased density at the base of the brain along the course of the major arterial vessels, and abnormally dense-appearing deep venous structures, like those of contrast-enhanced CT. There was a diffuse decrease in brain density with a poorly delineated ventricular system. These CT findings were very characteristic. CT as a non-invasive method seems to be valuable in the diagnosis of brain death. The relevant literature is reviewed and mechanisms showing those CT findings are discussed.  相似文献   
993.
The serum antibody response of 50 infants and children infected with respiratory syncytial virus (RSV) was determined by a glycoprotein-specific enzyme-linked immunosorbent assay, and the effects of age and preexisting antibody titer at the time of RSV infection on response to the G and F glycoproteins of RSV were examined. The immune response to the G and F glycoproteins was assessed with anti-human immunoglobulin A to permit measurement of the response of young infants in the presence of maternally derived immunoglobulin G. The findings suggested that age primarily affects the response to the F glycoprotein and that preexisting antibody titer affects the response to the G glycoprotein.  相似文献   
994.
Diastematomyelia is a rare congenital anomaly characterized by a division of the spinal cord or the filum terminale into two parts. In Korea, only one case has been reported. The authors have operated on 5 cases of diastematomyelia with septum since July, 1978. The ages ranged from 1 to 44 years (median; 11 years). There were 2 boys, 2 girls and an adult man. The disease manifested by cutaneous abnormalities and neurological or orthopedic deficits. Pain was a chief complaint in the adult patient. The symptoms had progressed in 3 cases. The diagnosis was made correctly by CT myelography or MRI in 4 cases. The median septum was located at the lumbar area in 4 cases and at the lumbosacral region in 1 case. Associated abnormalities included low lying conus (5 cases), lipoma (2 cases), thickened filum terminale (1 case), hemilipomyelomeningocele (1 case) and syrinx (1 case). The median septum was removed. The dural sleeve adjoining the septum was resected and the dural sac was reconstructed. The role of MRI in the diagnosis and planning of surgery and the high frequency of associated low lying conus were emphasized. Though the surgical treatment relieved pain, it did not reverse the neurological deficits or orthopedic deformities significantly, which suggests the beneficial effects of early surgical intervention in the cases with progressive symptoms.  相似文献   
995.
Characterization of a single base-pair deletion in neurofibromatosis type 1   总被引:1,自引:0,他引:1  
The gene which is responsible for neurofibromatosis type 1 (NF1)is located on chromosome 17 (17q11.2). The NF1 gene is approximately350 kilobases (kb) long and exhibits an extremely high mutationrate; therefore, most patients are expected to have unique mutations.To date, relatively few mutations have been well characterized.We report here a de novo single base pair (bp) deletion in oneNF1 allele in a patient diagnosed with NF1 and leukemia. Wefurther characterized this mutation at the RNA level by allele-specificoligonucleotide (ASO) hybridization which demonstrated thatthe mutant allele is transcribed.  相似文献   
996.
Anti-CD3 (OKT3) MoAb is a mitogenic agent which activates lymphocytes. We have studied the effects of murine anti-human OKT3 MoAb (IgG1) alone or in combination with IL-2, human thyroglobulin (Tg) and thyroperoxidase (TPO) antigens on the proliferation of whole peripheral blood mononuclear cells (PBMC) (including monocytes) or subtypes (T, CD4+, CD8+, B) as measured by tritiated thymidine (3H-TdR) incorporation. B cell differentiation was studied by measuring numbers of IgG-secreting cells and specific anti-TPO/anti-Tg-secreting cells by SPOT ELISA. PBMC or lymphocyte subtypes, obtained from 45 patients with Hashimoto's thyroiditis (HT), 40 Graves' disease (GD) and 51 normal controls were cultured in 96 microtitre plates for 6 days in the presence of OKT3 MoAb at final concentrations 25-250 ng/ml, IL-2 15 U/ml, Tg and TPO (1 micrograms/ml). Then cultures were pulsed with 0.2 microCi 3H-TdR/well and incorporation was measured after 18 h. IgG and anti-TPO/Tg-secreting cells were detected at 7 days. Higher proliferative responses from whole PBMC preparations in response to any of the combinations including OKT3 MoAb were observed in the HT preparations, while the basal values were the lowest. IL-2 alone increased these responses markedly, but equally in all groups. IL-2 in combination with OKT3 had an additive effect on proliferation, with higher responses in HT. Tg and TPO antigens did not change these responses. Most HT preparations responded with their maximum proliferation to the lowest concentration of OKT3 MoAb (25 ng/ml), whereas in GD and control preparations of PBMC these responses were shifted to higher concentrations (250 ng/ml); even with those, proliferation was not so enhanced in controls when compared with HT and GD preparations. In contrast, the proliferative responses of T cells alone and subpopulations of CD8+ suppressor/cytotoxic cells were decreased in HT preparations compared with controls. Monocytes were necessary for proliferation. In the subpopulation of B cells (> 95% pure) and CD4+ helper/inducer cells, differences did not reach significance. In spite of the effect on proliferation, OKT3 MoAb only mildly but significantly increased the numbers of IgG-secreting cells in HT and GD preparations and did not stimulate synthesis of specific antibodies. Our data suggest that the increased proliferative responses of whole PBMC to OKT3 MoAb in HT preparations might be due to insufficient activation of T suppressor/cytotoxic cells.  相似文献   
997.
Pain behaviors that are excessive for the degree of known physical disease are common in patients with chronic low back pain and are frequently assumed to arise from a comorbid depressive illness. Although some studies have confirmed an association between depression and excessive pain behavior, methodologic problems (such as the use of depression ratings that also recorded symptoms attributable to physical disease) make interpretation of this finding difficult. We recruited 54 consecutive patients with chronic (>6 months) low back pain from a hospital clinic. Subjects completed self-rated assessments of anxiety and depression (Hospital Anxiety and Depression Scale) designed to be minimally affected by physical symptoms, along with assessments of disability (ODQ), pain (visual analogue scale), pain behavior (Waddell checklist), and physical impairment. Seventeen subjects (31%) exhibited excessive pain behavior. Overall, they were no more depressed or anxious than the remainder, although men with excessive pain behavior showed a trend toward being more depressed. Patients with excessive pain behavior were more disabled (self-rated and observer-rated), reported greater pain, and were more likely to be female and to have pain of shorter duration. Pain behavior did not correlate with anxiety or depression, but correlated with measures of disability and pain intensity. Factor analysis revealed that physical disability, pain intensity, and pain behavior loaded heavily on the first factor. Anxiety and depression loaded together on a separate factor. We conclude that pain behaviors were not related to anxiety or depression in our group, although gender differences between groups could have contributed to our negative findings. Pain behaviors may influence other physical measures. Further studies are required to investigate the relation between depression and pain behavior while controlling for gender differences.  相似文献   
998.
Anderson-Fabry disease (AFD) is an X-linked disorder caused by deficient activity of the lysosomal enzyme alpha-galactosidase A. The availability of enzyme replacement therapy (ERT) for this debilitating condition has led to the need for a convenient and sensitive instrument to monitor clinical effects in an individual patient. This study aimed to develop a scoring system--the Mainz Severity Score Index (MSSI)--to measure the severity of AFD and to monitor the clinical course of the disease in response to ERT. Thirty-nine patients (24 males and 15 females) with AFD were assessed using the MSSI immediately before and 1 year after commencing agalsidase alfa ERT. Control data were obtained from 23 patients in whom AFD was excluded. The MSSI of patients with AFD was significantly higher than that of patients with other severe debilitating diseases. The MSSI indicated that, although more men than women had symptoms classified as severe, overall, the median total severity scores were not significantly different between male and female patients. One year of ERT with agalsidase alfa led, in all patients, to a significant (p < 0.001) reduction in MSSI score (by a median of nine points). This study has shown that the MSSI score may be a useful, specific measure for objectively assessing the severity of AFD and for monitoring ERT-related treatment effects.  相似文献   
999.
To construct the PAC and cosmid contig map spanning the HOXA cluster on human chromosome 7, we used 9 DNA markers (D7S2243, D7S3010, HOXA1, EVX1, 750, pBH8, p60, p8.0, and HOXA11), among which the final 4 were generated in this study by shotgun cloning strategy. From the libraries, 5 PAC and 35 cosmid clones were screened and as a result, an overlapping continuous array of cosmid and PAC clones covering the genomic region (about 200 kb) spanning the entire cluster were constructed. The isolated cosmids contained several consecutive HOX genes of regional group, probably sharing the regulatory processes such as alternative splicing or polyadenylation, and thus could be used as useful materials for elucidating the molecular mechanism of HOX gene expression in the future.  相似文献   
1000.
Site-directed mutagenesis has been used to change amino acid residues of a recombinant Fc-hinge fragment derived from the murine immunoglobulin (Ig)G1 molecule, and the effects of these mutations on the pharmacokinetics of the Fc-hinge fragment have been determined. Specifically, Ile-253, His-310 and Gln-311 of the CH2 domain and His-433 and Asn-434 of the CH3 domain have been changed. In the three dimensional structure of an antibody, these amino acids are in close proximity to each other at the CH2-CH3 domain interface. The mutated Fc-hinge fragments have been purified from recombinant Escherichia coli cells and their pharmacokinetic parameters determined in mice and compared with those of the wild-type Fc-hinge fragment. The results show that the site of the IgG1 molecule that controls the catabolic rate (the ‘catabolic site’) is located at the CH2-CH3 domain interface and overlaps with the Staphylococcal protein A binding site.  相似文献   
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