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81.
Chronic distal spinal muscular atrophy (Chronic DSMA, MIM (*)607088) is a rare autosomal recessive disorder characterized by a progressive motor weakness and muscular atrophy, predominating in the distal parts of the limbs. A form of Chronic DSMA gene has been previously mapped to chromosome 11q13 in the 10.3 cM interval defined by loci D11S1889 and D11S1321. By linkage analysis in 12 European Chronic DSMA families, we showed that a disease gene maps to chromosome 11q13.3 (Z(max)=6.66 at theta=0.00 at the DSM4 locus) and suggested that this condition is genetically homogeneous. Recombination events allowed us to reduce the genetic interval to a 2.6 cM region, telomeric to the IGHMBP2 gene, excluding this gene as the disease causing gene in Chronic DSMA. Moreover, partial linkage disequilibrium was found between three rare alleles at loci D11S1369, DSM4 and D11S4184 and the mutant chromosome in European patients. Analysis of the markers at these loci strongly suggests that most Chronic DSMA chromosomes are derived from a single ancestor. Refinement of the Chronic DSMA locus will hopefully allow to test candidate genes and lead to identification of the disease-causing mutations.  相似文献   
82.
Chromosome investigations were carried out in 7 patients with Fanconi's anemia, type Estren-Dameshek. The frequency and types of chromosome instability found in cultured lymphocytes were in accord with those detected in individuals with classical Fanconi's anemia. The break-point distribution indicates a significant excess of breaks in chromosomes No. 1, 2, and 7 and a deficit in No. 18 and X and Y chromosomes. There was a clear clustering of breaks at certain locations in chromosomes No. 1, 2, 3, 7, 9, and 14. The location of the breaks with respect to the bands demonstrated an almost exclusive involvement of the lighter bands, regardless of the banding method used. These results suggest that most breaks take place in the interbands between the G and R bands. In all patients, chromosome instability was less frequent in direct bone marrow preparations than in lymphocyte cultures. However, cultured bone marrow cells showed a significant increase of chromosome aberrations. On the whole, the chromosome data derived from this series of patients are in agreement with those obtained in individuals with classical Fanconi's anemia and give no support to the idea of cytogenetic heterogeneity between subjects affected by these two forms of childhood aplastic anemia.  相似文献   
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We report the seventeenth case of the recessive form of the DOOR syndrome. The parents were Guatemalan and not known to be consanguineous. The patient had developmental delay, severe sensorineural deafness, and abnormal nails and phalanges in the hands and feet. Urinary 2-oxoglutarate excretion was normal. The patient was among a subset of DOOR syndrome patients may be useful in discussing the prognosis for newly identified cases. © 1993 Wiley-Liss, Inc.  相似文献   
86.
We have shown that fetuses whose mothers underwent subtotal nephrectomy (STNx) before pregnancy had high urine flow rates and sodium excretions, but lower hematocrits, plasma chloride, and plasma renin levels compared with controls. To see if these functional differences in utero persist after birth and are the result of altered renal development, we studied 8 lambs born to STNx mothers (STNxL) and 10 controls (ConL) in the second week of life. These lambs were of similar body weights, nose–rump lengths and abdominal girths. Their kidney weights were not different (ConL 36.1 ± 1.9 vs. STNxL 39.8 ± 3.3 g), nor were kidney dimensions or glomerular number (ConL 423,520 ± 22,194 vs. STNxL 429,530 ± 27,471 glomeruli). However, STNxL had 30% larger glomerular volumes (both mean and total, P < 0.01) and there was a positive relationship between total glomerular volume and urinary protein excretion (P < 0.05) in STNxL. Despite this change in glomerular morphology, glomerular filtration rate, tubular function, urine flow, and sodium excretion rates were not different between STNxL and ConL, nor were plasma electrolytes, osmolality, and plasma renin levels. Thus while many of the functional differences seen in late gestation were not present at 1–2 weeks after birth, the alteration in glomerular size and its relationship to protein excretion suggests that exposure to this altered intrauterine environment may predispose offspring of mothers with renal dysfunction to renal disease in adult life. Anat Rec, 291:318–324, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
87.
Parkinson's disease (PD) is a progressive neurodegenerative illness associated with a selective loss of dopaminergic neurons in the nigrostriatal pathway of the brain. Despite the overall rarity of the familial forms of PD, the identification of single genes linked to the disease has yielded crucial insights into possible mechanisms of neurodegeneration. Recently, a putative mitochondrial kinase, PINK1, has been found mutated in an inherited form of parkinsonism. Here, we describe that PINK1 mutations confer different autophosphorylation activity, which is regulated by the C-terminal portion of the protein. We also demonstrate the mitochondrial localization of both wild-type and mutant PINK1 proteins unequivocally and prove that a short N-terminal part of PINK1 is sufficient for its mitochondrial targeting.  相似文献   
88.
Introduction The aims of the current study were to (i) tissue engineer a cartilage graft with structural and biochemical properties of native articular cartilage in vivo, with potential for use in cartilage repair technologies and (ii) utilize this model as a test system to evaluate the efficiency of novel therapeutics for future research into cartilage metabolism in health and disease. Materials and methods Articular cartilage was harvested from hock joints of (young) 7‐day and (old) 18‐month bovine sources. Cells were isolated by enzymatic digestion and seeded at a range of cell densities (2, 4, 6, 8, 10 and 12 × 106 cells/insert) into type II collagen‐coated Millipore filter inserts and cultured as described previously ( Kandel et al. 1995 ). In order to mimic a catabolic effect on cartilage, some samples were treated with IL‐1α (10 ng/ml) for 24 h in the absence or presence of experimental drugs. Proteoglycan (PG) release, detectable in the medium, was analysed by colorimetric assay ( Farndale et al. 1986 ). At the end of the culture period, cartilage grafts were fixed, sectioned and stained with Alcian Blue or immuno‐fluorescently labelled with a panel of monoclonal antibodies recognizing several components of the graft extracellular matrix. Results Full‐depth chondrocytes from both young and old bovine sources produced a stratified hyaline tissue with distinct zones after 2 weeks in culture. These zones approximated to the surface, middle and deep zones that characterize native articular cartilage in vivo. Increased culture time and seeding density produced cartilage of an increased thickness and cellularity, respectively. Grafts produced from young cartilage contained approximately 3 times more sulfated PG than grafts produced from an old cartilage, indicating an increased matrix secretion in these cultures. Histologically, the old grafts were also thinner and more weakly stained with Alcian Blue, indicating a lower sulfated PG content. Addition of IL‐1α to the cultures resulted in a dramatic PG release from the cartilage grafts, manifest histologically as a loss of Alcian Blue staining in the upper third of the cartilage tissue. Immunofluorescent staining identified subtle changes in matrix composition and in the structure and catabolism of matrix proteoglycans in response to both IL‐1a and the experimental drugs tested. Discussion The grafts produced had many structural and biochemical similarities to articular cartilage in vivo. These grafts may better integrate with the host cartilage in cartilage repair procedure. This culture system also provides ideal conditions to analyse the response of engineered grafts to catabolic factors that occur in the arthritic joint, along with ideal conditions for research into drug therapies. Advantages of this culture system, in comparison with an explant system, are that effects can be analysed within a 24‐h period. Future work will include applying fatty acids, modified glucosamine and some Asian herbal remedies to this culture system and analysing their potential chondroprotective effects.  相似文献   
89.
Kabuki syndrome (KS) is associated with multiple organ system involvement. Characteristic features include long palpebral fissures with everted lower lids, prominent ears, skeletal abnormalities, mental retardation, and short stature. An increased incidence of infection has been reported in KS, and a few patients have been noted to have immune defects. However, the frequency and severity of the immune deficiency has not been clearly defined. Immunologic evaluation of 19 consecutive individuals with KS was performed at The Children's Hospital of Philadelphia. Decreased IgA levels were noted in 15/19 individuals (79%), 2 of whom had undetectable levels. Eight patients (42%) also had low total IgG levels. Specific IgG subclass abnormalities were found in 6 of 13 patients evaluated. IgM levels were less frequently decreased. One patient failed to generate anti-tetanus antibodies despite immunization. This study suggests that hypogammaglobulinemia is a frequent finding in children with KS. The pattern of antibody abnormalities seen in children with KS resembles common variable immune deficiency (CVID). Due to this increased susceptibility to infection, children with KS should have immunologic evaluations at the time of diagnosis in order to reduce preventable morbidity and mortality.  相似文献   
90.
OBJECTIVE: Ospemifene, a novel selective estrogen receptor modulator (SERM), shows promise for bone preservation in postmenopausal women. This study examined the effects of ospemifene on different vascular surrogate markers. DESIGN: A double-blinded study was conducted in 160 healthy, postmenopausal women who used, in a randomized order, ospemifene (at daily doses of 30, 60, or 90 mg) or placebo for 3 months. RESULTS: Although ospemifene caused falls from basal levels in total cholesterol, low-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, and a rise in high-density lipoprotein cholesterol, the only statistically significant difference between ospemifene and placebo was an increase of triglyceride levels (11.3%) in the 90-mg group. Ospemifene caused no significant effect on endothelial markers or homocysteine. Of the markers reflecting coagulation and fibrinolysis, plasma fibrinogen was significantly reduced in the 60- and 90-mg groups of ospemifene (8.7% and 8.5%, respectively) when compared with the placebo group. No changes were seen in generation of thrombin or degradation of crosslinked fibrin D-dimer. The uterine or carotid arteries and 24-h ambulatory blood pressure were not affected by ospemifene. Ospemifene caused no changes in basal insulin or in a 2-h glucose tolerance test, suggesting unaltered insulin sensitivity. CONCLUSIONS: Neutral effects of short-term use of ospemifene on vascular surrogate markers imply no effect for ospemifene on the risk for cardiovascular disorders in healthy, postmenopausal women.  相似文献   
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