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121.
122.
Developmental foundations of externalizing problems in young children: the role of effortful control 总被引:4,自引:0,他引:4
Examined associations between effortful control temperament and externalizing problems in 220 3-year-old boys and girls, controlling for co-occurring cognitive and social risk factors. We also considered possible additive and/or interactive contributions of child dispositional anger and psychosocial adversity, and whether relations between effortful control and early externalizing problems were moderated by child gender. Individual differences in children's effortful control abilities, assessed using behavioral and parent rating measures, were negatively associated with child externalizing problems reported by mothers, fathers, and preschool teachers. These associations were not overshadowed by other cognitive or social risk factors, or by other relevant child temperament traits such as proneness to irritability. Further analyses revealed that associations between externalizing problem behavior and effortful control were specific to components of child problem behavior indexing impulsive-inattentive symptoms. Thus, children's effortful control skills were important correlates of children's early disruptive behavior, a finding that may provide insight into the developmental origins of chronic behavioral maladjustment. 相似文献
123.
CD39 activity correlates with stage and inhibits platelet reactivity in chronic lymphocytic leukemia
Dianne Pulte Kim E Olson M Johan Broekman Naziba Islam Harold S Ballard Richard R Furman Ashley E Olson Aaron J Marcus 《Journal of translational medicine》2007,5(1):23
Background
Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its metabolism of ADP to AMP. We hypothesize that if CD39 is observed on CLL cells, then patients with CLL may be relatively protected against platelet aggregation and recruitment and that CD39 may have other effects on CLL, including modulation of the disease, via its metabolism of ATP. 相似文献124.
The DNA of the human serum amyloid A (SAA) gene GSAA1 contains several repetitive regions within its introns. We have studied length variations at one such region in the 2nd intron by selective amplification using the polymerase chain reaction (PCR) and defined oligonucleotide primers. The lengths of the repetitive regions frequently differ between individual chromosomes and can be transmitted as Mendelian markers, making them useful for genetic linkage analysis. 相似文献
125.
Peter A. Shapiro Richard P. Sloan Emilia Bagiella J. Thomas Bigger JR. Jack M. Gorman 《Psychophysiology》1996,33(1):54-62
Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation. 相似文献
126.
Cellular and developmental patterns of expression of Ret and glial cell line-derived neurotrophic factor receptor alpha mRNAs 总被引:6,自引:0,他引:6
C. A. Nosrat Andreas Tomac Barry J. Hoffer Lars Olson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,115(3):410-422
Glial cell line-derived neurotrophic factor (GDNF) has recently been shown to signal by binding to GDNF receptor-alpha (GDNFR-α),
after which the GDNF-GDNFR-α associates with and activates the tyrosine kinase receptor Ret. We have localized Ret messenger
RNA (mRNA) in the developing and adult rodent and compared with to the expression of GDNF and GDNFR-α mRNA. Ret mRNA is strongly
expressed in dopamine neurons and α-motorneurons as well as in thalamus, ruber and occlumotor nuclei, the habenular complex,
septum, cerebellum, and brain stem nuclei. Ret mRNA was also found in several sensory systems, in ganglia, and in nonneuronal
tissues such as teeth and vibrissae. Very strong Ret mRNA signals are present in kidney and the gastrointestinal tract, where
Ret and GDNF mRNA expression patterns are precisely complementary. The presence of Ret protein was confirmed in adult dopamine
neurons using immunohistochemistry. GDNFR-α mRNA was strongly expressed in the developing and adult dopamine neurons. It was
also found in neurons in deep layers of cortex cerebri, in hippocampus, septum, the dentate gyrus, tectum, and the developing
spinal cord. In the kidney and the gastrointestinal tract, GDNFR-α mRNA and Ret mRNA distribution overlapped. Dorsal root
ganglia, cranial ganglia, and developing peripheral nerves were also positive. GDNFR-α was additionally found in sensory areas
and in developing teeth. Sensory areas included inner ear, eye, olfactory epithelium, and the vomeronasal organ, as well as
developing tongue papillae. The temporospatial pattern of expression of GDNFR-α mRNA did not always match that of Ret mRNA.
For instance, GDNFR-α mRNA was also found in the developing ventral striatum, including the olfactory tubercle, and in hippocampus.
These areas seemed devoid of Ret mRNA, suggesting that GDNFR-α might also have functions unrelated to Ret.
Received: 2 January 1997 / Accepted: 26 February 1997 相似文献
127.
IgG antibody to gE, the Fc gamma-binding herpes simplex 1 (HSV-1) viral glycoprotein, was studied in 49 rheumatoid arthritis (RA) patients and 43 normal controls. Antibody to gD, another important HSV-1 antigen, was assayed in parallel. No difference between RA patients and normal controls was found in levels of anti-gE antibody measured by reactivity of IgG F(ab')2 fragments reacting with gE coated to ELISA plates. No difference in anti-gD antibody was recorded between normals and patients with RA. Levels of IgG anti-IgE antibody did not correlate with quantitative elevations of serum rheumatoid factor (RF) in RA patients. When IgG anti-gE and anti-gD were assayed in 20 patients with juvenile rheumatoid arthritis and 22 children controls, no significant differences were noted. However, when individual RFs from patients with RA were tested for reactivity against a panel of affinity-isolated F(ab')2 antibodies to gE, some evidence for individual autospecificity was obtained. Four of 20 monoclonal IgM RFs produced from RA patients' B cells showed marked elevations of reactivity with some RA patients' F(ab')2 antibodies to gE. All four of the monoclonal RFs showing this specificity were derived from RA synovial tissue B cells. These findings may provide support for the concept that some RFs in patients with RA show individual specificity for internal image determinants of IgG antibodies to viral Fc gamma-binding proteins. 相似文献
128.
129.
Brilakis ES Olson LJ Berry GJ Daly RC Loisance D Zucker M Cooper LT 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2000,46(5):569-572
Giant cell myocarditis is a highly lethal disorder characterized by rapidly progressive congestive heart failure. The aim of this study was to describe the clinical course of patients with giant cell myocarditis who received a ventricular assist device. Patients with giant cell myocarditis were identified from the Multicenter Giant cell Myocarditis Registry. Bridging to cardiac transplantation in the giant cell myocarditis patients who received a ventricular assist device was compared with bridging in the general population of heart failure patients, as reported in the literature. Median posttransplantation survival for patients with giant cell myocarditis who received and did not receive ventricular assist devices was calculated by the Kaplan-Meier method and compared with use of the log-rank test. Nine patients with giant cell myocarditis who received ventricular assist devices were identified. Seven patients survived to transplantation, four were alive 30 days posttransplantation, and two survived to 1 year. The rate of successful bridging to transplantation in seven of nine patients (78%) is similar to that reported for other ventricular assist device recipients. Posttransplantation survival of 57% (4 of 7) at 30 days and 29% (2 of 7) at 1 year was significantly lower compared with 93% 1-year survival of the 30 patients with giant cell myocarditis who did not receive ventricular assist devices before transplantation (p<0.001). Ventricular assist devices can be an effective bridge to transplantation for patients with heart failure caused by giant cell myocarditis. Although their posttransplantation survival was poor in our series, a few patients had long-term survival. 相似文献
130.
C A Olson E W Cupp S Luckhart J M Ribeiro C Levy 《Journal of medical entomology》1992,29(6):1060-1062
Adults and immatures of Ixodes pacificus Cooley & Kohls were collected by flagging vegetation and from lizards during a 3-mo period in the Hualapai Mountain Park, Mohave County, AZ, in 1991. Collections were made at altitudes > or = 2,134 m. Two of 48 gut-salivary gland extracts of adult ticks were positive by IFA using a monoclonal antibody (H5332) specific to Borrelia burgdorferi. These are the first records of I. pacificus and of spirochetes tentatively identified as B. burgdorferi in Arizona. 相似文献