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31.
OBJECTIVE: To examine psychosocial predictors of distress (mood disturbance, perceived stress, caregiver burden) in parents of children undergoing stem cell or bone marrow transplantation (BMT). METHOD: Measures of prior illness experiences, premorbid child behavior problems, family environment, social support, and parental coping behavior were obtained from the resident parents of 151 children prior to the children's admission for BMT. Parents subsequently completed assessments of their mood disturbance, perceived stress, and caregiving burden on a weekly basis through week +6 post-BMT, and then monthly through month +6 post-BMT. RESULTS: Significant changes were observed in parental distress across the course of BMT. After correcting for demographic and medical factors, several significant predictors of parental distress trajectories were identified, including prior parent and patient illness-related distress, premorbid child internalizing behavior problems, the family relationship dimensions of the family environment, and parental avoidant coping behaviors. Multivariable models were developed using a hierarchical modeling approach. The best-fit model accounted for approximately 50% of the variance in parental global distress. CONCLUSIONS: Subgroups of parents at higher risk for increased distress during the acute phase of transplant have been identified. These findings can help target parents who may be in greater need of intervention aimed at reducing transplant-related distress. 相似文献
32.
Seminoma in a postmenopausal woman with a Y;15 translocation in peripheral blood lymphocytes and a t(Y;15)/45,X Turner mosaic pattern in skin fibroblasts. 下载免费PDF全文
N Hoshi M Fujita M Mikuni T Fujino K Okuyama Y Handa H Yamada T Sagawa H Hareyama Y Nakahori K Fujieda J A Kant K Nagashima S Fujimoto 《Journal of medical genetics》1998,35(10):852-856
We report an unusual case of a 55 year old Japanese woman with a seminoma but relatively normal menses. The patient was a phenotypic female with late onset menarche (18 years of age), who was amenorrhoeic for the first year, followed by menses of one to three days' slight flow with dysmenorrhoea, but an otherwise normal menstrual history. A typical seminoma was removed from the left adnexal region and an immature testis was identified separately as an associated right adnexal mass. Repeated karyotypic studies on peripheral blood lymphocyte cultures showed only 46,X,-Y,t(Y;15)(q12;p13). Cytogenetic examination of the patient's younger brother, who had fathered three healthy children, showed an identical karyotype. Mosaicism of 46,X,-Y,t(Y;15)(q12;p13)/45,X cell lines was found in skin samples from the patient's elbow and genital regions, although there were no clinical stigmata of Turner syndrome. An androgen receptor binding assay of cultured genital skin fibroblasts was negative. Molecular analysis using Southern blot hybridisation, PCR, and direct DNA sequencing showed that neither the patient nor her brother had a detectable deletion or other abnormalities of Y chromosome sequences, including the SRY (sex determining region of the Y chromosome) gene sequence. These findings suggest that Turner mosaicism of the 45,X cell line may have contributed to this atypical presentation in an XY female, although we cannot exclude abnormalities of other genes related to sex differentiation. 相似文献
33.
K. S. Kohli Dr. D. V. Rai V. K. Jindal N. Goyal 《Medical & biological engineering & computing》1998,36(5):604-607
A computer assisted AC impedance system is used to measure the DC voltage—current (V-I) characteristics and AC impedance of
a goat eye lens using a two-probe Ag−AgCl electrode system. The measurement of the V-I characteristics shows that when a DC
voltage from 0mV to 30mV is applied, the resultant current decreases from an initial value of 0.58μA to 0.006μA. However,
when the voltage is increases beyond 30mV, the current increases and reaches a value of 0.9μA at 100mV. The data on the frequency
response (0.01–10 Hz) of the impedance of lens tissue show an inverse relationship with frequency. The effect of various DC
voltages, namely 0, 30, 50, 100 and 200 mV, on the impedance of the eye lens is also investigated over a frequency range of
0.01–10 Hz. The measurement results for both V-I characteristics and AC impedance further suggest the presence of a 30 mV
voltage compartment in the goat eye lens. 相似文献
34.
D. G. Hicks V. A. LiVolsi J. A. Neidich J. M. Puck J. A. Kant 《The American journal of pathology》1990,137(3):553-562
Accumulated data using functional, morphologic, and histochemical analysis suggests that follicular proliferations in the thyroid include polyclonal and monoclonal patterns with encapsulated follicular adenomas most frequently monoclonal, and other nodules generally polyclonal. However, examples of polyclonal carcinomas or adenomas raise the possibility that histologically similar lesions may arise through different pathogenetic mechanisms. The authors have performed a clonal analysis of histologically benign and malignant thyroid nodules in seven women using HPRT (hypoxanthine phosphoribosyl transferase) and PGK (phosphoglycerate kinase) restriction fragment length polymorphisms (RFLPs) on the X chromosome. These RFLPs used in concert with methylation-sensitive restriction endonucleases HpaII and HhaI permit distinction of active and inactive X chromosomes. DNA from a multinodular goiter showed equal sensitivity of both X chromosome RFLP alleles to a methylation-sensitive restriction endonuclease, consistent with a polyclonal origin. In contrast, three solitary follicular nodules and three carcinomas displayed predominant sensitivity of a single RFLP allele, consistent with a monoclonal origin. Although further detailed studies will be necessary to understand polyclonal origins reported for some adenomas, our data from a limited number of samples supports a predominantly monoclonal origin, and possible neoplastic pathogenesis, for many solitary adenomatous nodules in the thyroid. 相似文献
35.
We have analysed the hypervariable regions (HVR I and II) of human mitochondrial DNA (mtDNA) in individuals from Uttar Pradesh (UP), Bihar (BI) and Punjab (PUNJ), belonging to the Indo-European linguistic group, and from South India (SI), that have their linguistic roots in Dravidian language. Our analysis revealed the presence of known and novel mutations in both hypervariable regions in the studied population groups. Median joining network analyses based on mtDNA showed extensive overlap in mtDNA lineages despite the extensive cultural and linguistic diversity. MDS plot analysis based on Fst distances suggested increased maternal genetic proximity for the studied population groups compared with other world populations. Mismatch distribution curves, respective neighbour joining trees and other statistical analyses showed that there were significant expansions. The study revealed an ancient common ancestry for the studied population groups, most probably through common founder female lineage(s), and also indicated that human migrations occurred (maybe across and within the Indian subcontinent) even after the initial phase of female migration to India. 相似文献
36.
B S Ooi K S Kant I B Hanenson A J Pesce V E Pollak 《Clinical and experimental immunology》1977,30(1):56-61
The present study was undertaken to determine the prevalence and nature of lymphocytotoxic antibodies in patients receiving phenytoin. Of forty-six sera examined, lymphocytotoxins and antinuclear antibodies were detected in fourteen and eleven samples respectively. Antibodies to double-stranded RNA (poly-A-poly-U) were found in six out of thirty-eight sera studied. A highly significant correlation was found between the presence of lymphocytotoxins and antinuclear antibodies (chi2 = 9.72; P less than 0.01). Lymphocytotoxins were found to be of the IgM class, to have activity against T and B cells, and to be dependent on the presence of Ca and Mg ions for activity. These findings may have pathogenetic importance in the genesis of the altered immune state of patients reveiving phenytoin. 相似文献
37.
Roest RW Carman WF Maertzdorf J Scoular A Harvey J Kant M Van Der Meijden WI Verjans GM Osterhaus AD 《Journal of medical virology》2004,73(4):601-604
Clinical recurrences of Herpes simplex virus type 1 (HSV-1)-associated genital herpes are thought to be caused by reactivation of latent endogenous HSV-1. However, the possibility of reinfection with exogenous HSV-1 cannot be excluded. This study aimed to determine the incidence of genital HSV-1 superinfection in patients by investigating the genotype of sequential HSV-1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV-1 recurrent genital herpes. Sequential genital HSV-1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV-1 genes US1 and US12. Whereas the sequential HSV-1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV-1-induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV-1 strain. 相似文献
38.
Pitt-Rogers-Danks syndrome and Wolf-Hirschhorn syndrome are caused by a deletion in the same region on chromosome 4p 16.3. 总被引:2,自引:1,他引:2 下载免费PDF全文
S G Kant A Van Haeringen E Bakker I Stec D Donnai P Mollevanger G C Beverstock M C Lindeman-Kusse G J Van Ommen 《Journal of medical genetics》1997,34(7):569-572
Recently, a deletion of chromosome 4pter was found in three patients with Pitt-Rogers-Danks syndrome. We investigated two of these patients, by means of DNA and FISH studies, together with two additional patients with Pitt-Rogers-Danks syndrome, to determine the critical region of the deletion in these patients and to compare this with the critical region in Wolf-Hirschhorn syndrome. All four patients showed terminal deletions of chromosome 4p of different sizes. One of them appeared to have an unbalanced karyotype caused by a cryptic translocation t(4;8) in the mother, resulting in a deletion of chromosome 4pter and a duplication of chromosome 8pter. The localisation of the Wolf-Hirschhorn critical region has been confined to approximately 1 Mb between D4S43 and D4S115. Our study shows that the deletions in four patients with the Pitt-Rogers-Danks syndrome overlap the Wolf-Hirschhorn critical region and extend beyond this in both directions. This study, combined with the fact that our third patient, who was previously described as a Pitt-Rogers-Danks patient, but who now more closely resembles a Wolf-Hirschhorn patient, makes it likely that Pitt-Rogers-Danks and Wolf-Hirschhorn syndromes are different clinical phenotypes resulting from a deletion in the same microscopic region on chromosome 4p16. 相似文献
39.
Erdreich-Epstein A Liu M Kant AM Izadi KD Nolta JA Durden DL 《Journal of leukocyte biology》1999,65(4):523-534
Cbl is a cytosolic protein that is rapidly tyrosine phosphorylated in response to Fc receptor activation and binds to the adaptor proteins Grb2, CrkL, and Nck. A few reports describe Cbl interactions in primary human hematopoietic cells. We show evidence that Cbl participates in signaling initiated by Fc gammaRI receptor cross-linking in human primary macrophages, and functions downstream of Src family kinases in this pathway. Fc gammaRI stimulation in human macrophages was associated with rapid and transient tyrosine phosphorylation of the Cbl adaptor protein. Immunoprecipitated Cbl was complexed with several tyrosine phosphorylated proteins, the most prominent of which was a 38-kDa band identified as the CrkL adaptor protein. CrkL associated with tyrosine-phosphorylated Cbl and itself became tyrosine phosphorylated after Fc gammaRI cross-linking. SLP-76, a recently cloned Grb2-associated protein, was strongly tyrosine phosphorylated after Fc gammaRI stimulation and was associated with both Cbl and Grb2. Grb2 and Cbl binding to SLP-76 were inducible after Fc gammaRI stimulation of the macrophages. Nck was inducibly bound to Cbl after Fc gammaRI stimulation, whereas Grb2 was constitutively associated with it. Shc was also inducibly tyrosine phosphorylated and bound to Grb2 after Fc gammaRI stimulation of the macrophages. PP1, a specific inhibitor of Src kinases, inhibited the Fc gammaRI-induced respiratory burst, as well as the tyrosine phosphorylation of Cbl and its inducible association with CrkL. These results suggest a fundamental role for the tyrosine phosphorylation of Cbl, CrkL, SLP-76, and Shc and the association of Cbl with CrkL, SLP-76, and Nck in Fc gammaRI signaling in human macrophages. Experiments performed with PP1, the specific Src kinase inhibitor, demonstrate the first evidence that Cbl and the Cbl-Crkl interaction are downstream targets for myeloid Src kinases required for the activation of myeloid NADPH oxidase activity. 相似文献
40.
BACKGROUND: Prolonged fatigue has recently attracted attention in occupational (mental) health research since it may lead to sickness absenteeism and work disability. To date, little is known about the role of psychosocial work characteristics in the aetiology of fatigue. In this study we examined prospectively a wide range of psychosocial work characteristics as possible risk factors for the onset of fatigue and psychological distress in the working population. METHODS: This study is based on 8833 employees, participating in the Maastricht Cohort Study of 'Fatigue at Work'. A wide range of psychosocial work characteristics, measured at baseline, was used to predict the onset of fatigue and psychological distress 1 year later. Fatigue was measured with the Checklist Individual Strength; the General Health Questionnaire was used to measure psychological distress. RESULTS: The cumulative incidence of fatigue during 1 year follow-up was 9.7% (N = 492) in men, and 13.5% (N = 241) in women. Psychological demands at work as well as physical and emotional demands increased the risk for fatigue in men, whereas decision latitude in men and co-worker social support in women were protective against fatigue. These prospective associations remained significant after adjustments for potential confounders and baseline fatigue. As regards psychological distress, no association was found with decision latitude, while conflicts at work increased the risk of psychological distress. CONCLUSIONS: Psychosocial work characteristics were significant predictors for the onset of fatigue in the working population. The prospective associations suggest some differential effects in the aetiology of fatigue and psychological distress. Good interpersonal relationships at work and high decision authority were demonstrated to be relevant aspects that should be targeted for prevention. 相似文献