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61.
Children conceived using ICSI do not have an increased risk of delayed mental development at 5 years of age 总被引:5,自引:0,他引:5
Leslie GI Gibson FL McMahon C Cohen J Saunders DM Tennant C 《Human reproduction (Oxford, England)》2003,18(10):2067-2072
BACKGROUND: Concerns about possible adverse outcomes for children conceived using ICSI were highlighted in 1998 when 1-year-old ICSI children were found to be at increased risk (relative risk = 9.2) of delayed mental development compared with children conceived naturally or using IVF. As the findings were biologically plausible, it was considered important to reassess child development when a more accurate measure of long-term cognitive ability could be obtained. METHODS: The mental development of 97 ICSI, 80 IVF and 110 naturally conceived (NC) children at 5 years of age was assessed using intelligence quotients (IQ) obtained from the Wechsler Preschool and Primary Scales of Intelligence. RESULTS: The mean full-scale IQ was 110 +/- 18 for ICSI, 111 +/- 13 for IVF and 114 +/- 13 for NC children (P = 0.21, non-significant). ICSI children were not at increased risk for delayed (full-scale IQ <85) cognitive development (ICSI 5.2%, IVF 2.5%, NC 0.9%; P = 0.18, non-significant). The only significant independent predictor of below-average full-scale IQ on multivariate analysis was lower maternal education level. CONCLUSIONS: These findings suggest that the genetic influence of parental cognitive ability is more important than the mode of conception in determining the long-term intellectual ability of children conceived using ICSI. 相似文献
62.
G N Gephardt R R Tubbs K L Popowniak J T McMahon 《Archives of pathology & laboratory medicine》1986,110(10):902-905
To evaluate the deposition of immunoglobulins and complement and their relationship to sclerotic and nonsclerotic glomerular segments, immunoperoxidase without periodic acid-Schiff counterstain (IMP) and with periodic acid-Schiff counterstain (IMPAS) for IgG, IgA, IgM, and C3 was performed on cryostat-frozen sections using the direct method, along with routine light microscopy and electron microscopy, in a series of 20 renal biopsy specimens from 20 patients with the final diagnosis of focal and segmental glomerulosclerosis. Neither diffuse mesangial nor diffuse glomerular basement membrane deposits were detected by IMP, IMPAS, or electron microscopy. In 18 biopsy specimens, IMPAS demonstrated focal and segmental granular to globular deposits of IgM and/or C3 in sclerotic glomerular segments. In eight biopsy specimens, small granular deposits of IgM and/or C3 deposits were identified in optically normal glomeruli, suggesting that these deposits may precede segmental sclerosis. 相似文献
63.
A whole trout preparation (Salmo gairdneri) externally ventilated with water and internally perfused with artificial medium via a cardiac pump is discribed for the study of O2 exchange and vascular resistance. As cardiac output (Q) was raised, ventral and dorsal aortic pressures increased while branchial (Rg) and systemic (Rs) vascular resistances fell, reflecting considerable passive distensibility. Arterial oxygenation was negative at low Qs due to significant internal O2 demand by the gill tissue, but increased to zero or positive values at intermediate Qs, and eventually declined at high Qs because of transit time limitation. O2 uptake from the ventilatory flow rose with increasing Q. Epinephrine (10(-5) M) decreased Rg, increased Rs, and enhanced arterial oxygenation. Artificial elevation of dorsal aortic pressure decreased Rg but did not affect arterial oxygenation. A 10-fold elevation of ventilatory flow increased arterial oxygenation but did not alter Rg or Rs. Endogenous metabolism of branchial tissue accounted for 11.7% of resting O2 uptake in vivo, and comprised an internal component taking O2 from perfusion flow and an external component drawing O2 from ventilatory flow. 相似文献
64.
Dick DM Foroud T Edenberg HJ Miller M Bowman E Rau NL DePaulo JR McInnis M Gershon E McMahon F Rice JP Bierut LJ Reich T Nurnberger J 《American journal of medical genetics》2002,114(4):407-412
Analyses of a replication sample of families collected as part of the National Institute of Mental Health (NIMH) Genetics Initiative for bipolar disorder provide further evidence for linkage to a region of chromosome 16. Families who had a bipolar I (BPI) proband and at least one BPI or schizoaffective, bipolar type (SABP) first-degree relative were ascertained for the purpose of identifying genes involved in bipolar affective disorder. A series of hierarchical models of affected status was used in linkage analyses. Initial genetic analyses of chromosomes 3, 5, 15, 16, 17, and 22, completed at Indiana University in 540 subjects from 97 families, suggested evidence of linkage to chromosomes 5, 16, and 22 [Edenberg et al., 1997: Am J Med Genet 74:238-246]. Genotyping was subsequently performed on these chromosomes in a replication sample of 353 individuals from 56 families. Nonparametric linkage analyses were performed using both affected relative and sibling pair methods. Analyses in the new sample on chromosome 16, using the broadest model of affected status, corroborate previously reported suggestive linkage to the marker D16S2619. Combining the initial and replication samples further increased the evidence of linkage to this region, with a peak lod score of 2.8. 相似文献
65.
We have studied quantitatively the levels of substance P and calcitonin gene-related peptide in nerves innervating skin and muscle of rats, and examined the effects of cross-anastomosing these nerves so that they regenerate to an inappropriate target. We have also compared the ability of nerves to induce neurogenic extravasation with their peptide content. Peptide was measured by radioimmunoassay in the proximal section of ligated peripheral nerves, and neurogenic oedema was measured by determination of Evans Blue extravasation induced by either systemic capsaicin treatment or topical mustard oil application. The levels of these peptides are higher in cutaneous nerves than muscle nerves. This cannot be explained by differences in the number of fibres in the nerves studied. The levels of peptides fall when cutaneous afferents reinnervate muscle, and rise when muscle afferents reinnervate skin. We suggest that these changes occur because of some tissue-specific trophic influence arising from the tissue innervated. The ability to produce extravasation in skin is highly correlated with the substance P and calcitonin gene-related peptide levels of its innervation, even when this occurs in inappropriate nerves which do not normally produce extravasation. 相似文献
66.
L F McMahon 《Evaluation & the health professions》1984,7(1):25-41
The new system for hospital reimbursement, called "reimbursement by diagnosis-related group" (DRG), offers a unique opportunity for the development of novel approaches to quality assurance. Groups of medically similar patients with stable patterns of resource use have been defined. These groups form the basis of the new payment system. Patients whose care deviates from the norm of resource consumption for their group, so-called outliers, will need to be reviewed by the hospital's administrative and medical staff. Such outliers are likely to constitute different types of patients than those in their assigned group: (1) patients whose medical complexity precludes grouping because of limitations in the abstracted clinical data; (2) patients whose medical care deviated because of complications of therapy or inappropriate diagnostic and/or therapeutic interventions; (3) patients whose medical course is so unique that they would never fit any classification system. The DRG-based reimbursement system, then, will compel hospitals to review the care of these outliers. The rigorous examination of these patients and their care, although just a first step, should be a major boon to quality of care evaluations. 相似文献
67.
Abrar M. Babateen Oliver M. Shannon Gerard M. OBrien Edward Okello Anmar A. Khan Sofia Rubele Emma Wightman Ellen Smith Nicholas McMahon Dilara Olgacer Christina Koehl William Fostier Inês Mendes David Kennedy John C. Mathers Mario Siervo 《Nutrients》2021,13(3)
Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO3−) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m2) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO3− (HN: 2 × 70 mL BJ/day) (2) medium-NO3− (MN: 70 mL BJ/day), (3) low-NO3− (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO3−-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO3− intake, and by measuring NO3− and NO2− concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO3− dose and the increase in plasma and urinary NO3− concentration (R2 = 0.71, p < 0.001 and R2 = 0.46 p < 0.001, respectively), but relationships between NO3− dose and changes in salivary NO3− and NO2− were non-linear (R2 = 0.35, p = 0.002 and R2 = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults. 相似文献
68.
69.
McMahon L 《The Health service journal》1990,100(5218):1356-1357
'Caring for people in Cornwall' is a project that involved GPs, the FHSA (Family Health Services Authority) and the HA (Health Authority) as three equal partners. Laurie McMahon explains how it evolved. 相似文献
70.
OBJECT: Cohort studies in pharmacoepidemiology can result in a unique type of study, where subjects have complex types of exposure to drugs (with periods of non-exposure as well). The object of this paper is to explain how to calculate the sample size of such a study. METHOD: It is assumed that adverse events follow Poisson distributions in the two study groups. The null hypothesis is that the two groups have equal rates of disease. Formulae are provided to calculate the sample size required to significantly reject the null hypothesis. Sample size is given as the number of events, rather than the number of subjects entered. In a Poisson study, it is the ratio of the amount of person-years exposure in the two groups that is important to calculate sample size, rather than the actual amounts of exposure (or number of subjects in the study). Some examples are included. 相似文献