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11.
Seven cases of granular cell Abrikossoff tumours of the larynx and tongue are reported: four in the tongue and three in the larynx. All of these tumours were removed with the carbon dioxide (CO2) laser. The anatomical site of the origin and clinical features of granular cell tumours (GCT) are not specific. Histological, light microscopic, electron microscopic (EM) and immunohistochemical studies are required for diagnosis. The histogenesis and cellular derivation of GCTs is still controversial. The biological potential and lack of cellular atypia define a benign process. However, it is important to take into account that these tumours have ill-defined borders without a capsule. Radiation therapy has proved ineffective in the past. Surgical excision with a wide margin is required. Because of numerous advantages, for example, no bleeding, no oedema, minimal pain and quick recovery, CO2 laser removal is the treatment of choice. The authors have not seen any recurrence or complications. 相似文献
12.
E. Schulte-Frohlinde S. Schmolke W. Reindl G. Schätzle J. Scherf K. F. Kopp M. Classen & V. Schlüter 《Journal of viral hepatitis》1998,5(5):341-344
Patients on maintenance haemodialysis represent a high-risk group for parenterally transmitted viral infections, such as hepatitis B, C and G. In addition to hepatitis G virus (HGV) (GBV-C) RNA, analysed in previous studies, we characterized the seroprevalence rates of antibodies to the putative E2 protein (anti-E2) of HGV in a German cohort of patients on maintenance dialysis ( n = 72) in comparison to healthy blood donors ( n = 100). The presence of anti-E2 and/or HGV RNA as indicators of present or past HGV infection could be demonstrated in 34.7% of patients and in 16% of the blood donors ( P < 0.01). The infection rates with HGV seem to increase only during the first 6 years of haemodialysis. The simultaneous presence of viraemia and anti-E2 was found very rarely in patients and controls. Therefore, the emergence of anti-E2 indicates clearance of HGV viraemia. In conclusion, patients on haemodialysis are at high risk of acquiring HGV infection, but a chronic carrier state with viraemia is rare. The risk of infection is not strictly correlated with the duration of dialysis. 相似文献
13.
Particular clinical pictures of ALS may occur during the course of some "benign gammapathies". We observed 12 patients (age range 57 to 74 years; 9 men-3 women) with initially benign gammapathy (9 IgG, 1 IgA, 2 IgM) associated to a clinical picture of progressive anterior horn and pyramidal tract involvement. These cases led us to recognize some particularities of gammapathy-associated ALS: Relative frequency of asymmetrical clinical manifestations, rarity of bulbar signs; Decrease of sensory nerve conduction velocities without evidence of sensory clinical symptoms (8 out 9); Increase CSF protein content including the monoclonal component, axonal degeneration and immunostaining evidence of the paraprotein fixation observed on nerve biopsies (5 out 7 cases). Association of ALS and gammapathy is not fortuitous as shown by epidemiology, experiments, pathology and effects of different immunological treatments as related in this study. Demonstration of infra-clinical neuropathy face to a clinical syndrome of ALS should prompt too careful screening for a gammapathy. 相似文献
14.
This paper reviews the literature on the role of dietary fat in calorie intake and body weight gain in humans and laboratory animals. An overview of 40 animal studies which compared growth on high-fat (HF) and high-carbohydrate (HC) solid/powdered diets indicated that the HF diet elicited greater weight gain in 33 out of 40 studies. Enhanced growth on the HF diet was often, but not exclusively, attributable to greater caloric intake. Additional evidence for the growth-enhancing effect of HF diets emerges from "diet option" and "supermarket" feeding studies in rats, and experimental and epidemiological studies in humans. Three principal factors that contribute to the different responses to HF and HC diets are (a) caloric density, (b) sensory properties and palatability, and (c) postabsorptive processing. It is concluded that both calorie intake and metabolic energy expenditure are biased towards weight gain when a HF diet is consumed, and that the high caloric density of high-fat diets plays a primary role in weight gain. Humans may be biologically predisposed to gain weight when a HF diet is consumed. 相似文献
15.
Kopp Z 《IPPF medical bulletin》1989,23(1):3-4
After a decade of investigations,, the US Food and Drug Administration (USFDA) approved the Prentif Cavity-Rim cervical cap on May 23, 1988. In use in many other countries since 1838, the findings of the USFDA-mandated study showed a theoretical-effectiveness rate of 93.6%, comparable to a 95.4% rate for the diaphragm. Use-effectiveness rates were 88.3% and 87.4% respectively. However studies revealed a wide range in reported efficacy rate and in the % of women who were able to be fitted for the cap. There are 4 cap sizes; when the cap is correctly in place a vacuum in created between the cervix and the cap. A health practitioner, trained in cap fitting, should do the initial fitting 40-60 minutes should be used to explain to and train the cap user. Contraindications to cap use include: an allergy to rubber or nonoxynol-9; inability to insert or remove the cap; and abnormal Pap smears. The USFDA study showed a 4% conversion rate from Class I to Class III Pap tests as compared to 1.7% for diaphragm users after 3 months. Beyond 3 months conversion rates were similar. Although these results have been questioned, the USFDA has requested that the manufacturer gather further data on Pap test conversions. Like diaphragm users, cervical cap users are less likely to contract sexually transmitted diseases; In contrast to a diaphragm the cervical cap can be left in place for up to 2 days; less spermicide is used, decreasing messiness; and the smaller size means increased comfort. The cervical cap should appeal to 3 groups: 1) women seeking a temporary method of family planning who are experiencing or concerned about side-effects with other methods, or for whom other methods are contra-indicated; 2) adolescents whose special needs require a temporary method with minimal side-effects which has not been found to affect future fertility; and 3) users concerned with preventing HIV infection and other sexually transmitted diseases, and who use the cap in conjunction with the condom. 相似文献
16.
17.
Hollie A. Power Jonathan A. Norton Cheryl L. Porter Zoe Doyle Isaiah Hui K. Ming Chan 《The Journal of physiology》2006,577(3):795-803
Intermuscular coherence analysis can be used to assess the common drive to muscles. Coherence in the β-frequency band (15–35 Hz) is thought to arise from common cortical sources. Intermuscular coherence analysis is a potentially attractive tool for the investigation of motor cortical excitability changes because it is non-invasive and can be done relatively quickly. We carried out this study to test the hypothesis that intermuscular coherence analysis was able to detect cortical excitability changes in healthy subjects following transcranial direct current stimulation (tDCS). tDCS has been shown to increase (anodal stimulation) or decrease (cathodal stimulation) the size of the muscle potential evoked by TMS. We found that anodal tDCS caused an increase in motor evoked potential (MEP) size that was paralleled by an increase in β-band intermuscular coherence. Similarly, the reduction in MEP size produced by cathodal tDCS was paralleled by a reduction in β-band intermuscular coherence, while sham stimulation did not result in any change in either MEP amplitude or β-band intermuscular coherence. The similar pattern of change observed for MEP and intermuscular coherence may indicate similar mechanisms of action, although this cannot be assumed without further investigation. These changes do suggest that at least some of the action of tDCS is on cortical networks, and that combined tDCS and intermuscular coherence analysis may be useful in the diagnosis of pathologies affecting motor cortical excitability. 相似文献
18.
Helen Vaughan Victoria J Chalker Zoe Mee Anneline Rossouw Vivienne James 《Journal of clinical virology》2006,35(2):135-140
BACKGROUND: The range of nucleic acid-based technologies for the molecular detection of pathogens has grown rapidly in recent years. The influx of new testing methods into the clinical laboratory, demands for evaluation and standardisation of methods, interpretation of results and evaluation of laboratory performance have highlighted the need for internal and External Quality Assessment (EQA) systems more than ever before. External Quality Assessment panels demand reproducible, stable specimens of consistent form, suitable for transportation. OBJECTIVES: To determine the stability of freeze-dried viral specimens in terms of molecular detection. STUDY DESIGN: When EQA specimens are prepared, they undergo long-term storage and testing as part of the quality control (QC) process. The frequency and nature of testing is dependent on the resources and methodologies available at the time. A range of virus preparations used for EQA was monitored over a period of months to years in a retrospective study; the available quality monitoring data for the five viruses, including storage temperature and method of detection were analysed. RESULTS: The nucleic acid (DNA or RNA) of the freeze-dried viruses included in the study was readily detectable over a long period of time. Quantitative analysis indicated that detectable concentrations of nucleic acid post-freeze drying were similarly maintained. Storage temperature was an important factor in the stability of HCV, but other viruses were unaffected by storage at different temperatures. CONCLUSIONS: In summary, the molecular detection of nucleic acid (DNA or RNA) in freeze-dried specimens of HSV1, HSV2, HBV, HCV and HIV is possible even after prolonged storage, in some cases at a range of temperatures. Freeze drying allows large-scale production of viral specimens of high quality for EQA, which are stable in varying storage and shipment conditions. Furthermore, detection of each virus was possible with a range of commonly used molecular diagnostic methods. 相似文献
19.
Nora Franceschini Kari E North Jeffrey B Kopp Louise McKenzie Cheryl Winkler 《Genetics in medicine》2006,8(2):63-75
Nephrotic syndrome, characterized by edema, proteinuria, hyperlipidemia and low serum albumin, is a manifestation of kidney disease involving the glomeruli. Nephrotic syndrome may be caused by primary kidney disease such as focal segmental glomerulosclerosis. Mutations in the podocin gene, NPHS2, have been shown in familial and sporadic forms of steroid-resistant nephrotic syndrome, including focal segmental glomerulosclerosis. Podocin is an integral membrane protein located at the slit diaphragm of the glomerular permeability barrier. Complete information is lacking for the population frequency of some NPHS2 variants for all racial and ethnic groups. The most frequently reported variant, R229Q, is more common among European-derived populations than African-derived populations. We calculated crude odds ratios and 95% confidence intervals of childhood nephrotic syndrome and focal segmental glomerulosclerosis associated with R229Q heterozygosity using data from five studies. The R229Q variant is not associated with focal segmental glomerulosclerosis in the US population of African descent. In contrast, the R229Q variant is associated with a trend toward increased focal segmental glomerulosclerosis risk in European-derived populations, with an estimated increased risk of 20-40%. Our insight into the association between NPHS2 variants and nephrotic disease is hampered by the limitations of the existing studies, including small numbers of affected individuals and suboptimal control groups. Nevertheless, the available data suggest that large epidemiological case-control studies to examine the association between NPHS2 variants and nephrotic syndrome are warranted. 相似文献
20.
Although it is well known that cyclic production of sex hormones is essential to establish reproductive function and female characteristics, distant impacts of the activity of the female endocrine system result from a concert of delicate mechanisms. Estrogen is rather an instrument than a conductor in this physiological orchestra of the female. Thus, controversies in the explanation of results from studies on hormone replacement therapy (HRT) and cardiovascular disease (CVD) prevention might be eliminated, if we analyse not only the role of estrogen but a broader spectrum of factors leading to CVD. Authors would like to hypothesize that haemorheological changes in women around menopause, such as increased blood and plasma viscosity, haematocrit and fibrinogen, are largely responsible for the increased mortality in the post-menopausal life period. We believe that a cyclic withdrawal bleeding establishes a more favourable haemorheological condition, thus, sequentially administered estrogen might be protective in post-menopausal women. Nevertheless, other factors, that decrease blood viscosity, such as daily exercise, intake of ample amount of fluids as well as ideal nutrition, are equally important. We are confident that sequential HRT, as well as healthy life style and risk prevention programmes have their proper place in the management of this issue. 相似文献