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31.
Analysis of human dentine by infrared spectrophotometry suggests that ball-grinding may result in damage of the apatite crystallites.
The present study includes further assessments of this effect by X-ray diffraction, infrared spectroscopy, and electron microscopy.
Each of three coarse-ground dentine samples (Group I) was divided into three portions of 30 mg. One of these portions was
ball-ground for approximately 1 min (Group II), the second portion for 6 min (Group III), and the third portion for 23 min
(Group IV). The 002 reflection showed line broadening, most marked from Group II to III. Electron microscopy showed a gradual
change in crystallite appearance with increased grinding, most pronounced from Group II to III. These observations indicate
that by prolonged grinding a limit is approached where no further changes in the crystallites occur. Electron microscopy also
indicated that fracture of the crystallites might have occurred. This was probably accompanied by strains in the lattice.
The infrared spectra indicated that no breakdown of the apatite structure had occurred during the entire grinding. 相似文献
32.
33.
Type 2 diabetes mellitus (DM) is associated with an increased risk for both micro-and macrovascular complications, and cardiovascular diseases (CVD) are the most common causes of death in these patients, accounting for almost 70% of the deaths. Given the high prevalence of the condition and the expected global increase in the prevalence of type 2 DM, a case is made for prevention of these serious complications in order to reduce the individual morbidity and the economic burden on society. In this review we present the knowledge of how macrovascular disease in patients with type 2 DM may be prevented, and suggest possible strategies for doing so. A thorough search of the published literature was conducted and we first present relevant epidemiological studies demonstrating the impact of important risk factors for CVD in DM, such as dyslipidemia, hyperglycemia, hypertension, smoking, familial premature coronary heart disease and some non-classical risk factors such as hyperinsulinemia, insulin resistance, endothelial dysfunction and inflammation. Secondly, we review the results from published randomized controlled clinical trials and meta-analysis of these, evaluate the findings and suggest strategies for preventing CVD in patients with type 2 DM using non-pharmacological and pharmacological approaches. Present knowledge indicates that most patients with type 2 DM either have manifest CVD or have a high risk for future cardiovascular events, men with DM have a 2- to 4-fold; and women with DM a 3- to 5-fold increased risk for cardiovascular death compared with non-diabetic individuals. Care of patients with type 2 DM should include yearly risk assessment by the use of published risk equations or risk charts. On the background of this assessment, an individual risk reducing strategy should be tailored to each patient’s need, including the treatment of hyperglycemia, hypertension and dyslipidemia together with the use of aspirin (acetylsalicylic acid) and ACE inhibitors. Such measures can reduce the risk of cardiovascular events in patients with type 2 DM. 相似文献
34.
Peer K. Lilleng Odd R. Monge Anders Wall e Clement S. Trovik Markus Hordvik Johan H ie Olav Dahl Gisle Bang 《Acta oncologica (Stockholm, Sweden)》1997,36(4):438-440
Fibrosarcoma is a rare tumour in children. The potential of malignancy has been questioned. We present three cases of fibrosarcoma in children. The follow-up periods range from 10 to 37 years. The first patient had pulmonary metastases at the time of diagnosis in 1958. The primary tumour in fossa ischio-rectalis was resected in 1960. Lung metastases were resected in 1960 and 1989. Radiotherapy was given in 1992. He is still alive with metastases 37 years after the first manifestation of disease. The second patient had a primary tumour and several local recurrences in the mandible. He is alive without evidence of disease 4 years after resection of pulmonary metastases and 21 years after resection of the primary tumour. The third patient has no signs of recurrence or metastasic spread 10 years after a wide excision of subcutanous tumours of the left upper arm. The cases demonstrate a special tumour-entity of low-grade malignancy, which show a good prognosis and a wide spectrum of biological behaviour. 相似文献
35.
Acute effects on systemic circulation after intratracheal instillation of Curosurf or Survanta in surfactant-depleted newborn piglets 总被引:2,自引:0,他引:2
A Moen X-Q Yu R Almaas T Curstedt OD Saugstad 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(3):297-303
Systemic vasodilatation in surfactant-depleted newborn piglets is induced by 200 mg/kg of modified porcine lung surfactant (Curosurf™). The aim of this investigation was to study whether this effect is dependent on dose and could further be induced by instillation of a bovine surfactant preparation (Survanta™). Twenty-two 3–5-d old piglets were subjected to repeated saline lung lavage and then randomized to one of three groups. Instillation of either Curosurf 100 mg/kg ( n = 8), Survanta 100 mg/kg ( n = 7) or Curosurf 200 mg/kg ( n = 7) was performed through the endotracheal tube. Systemic vascular resistance decreased 7 (± 4)%, 15 (± 12)% and 18 (± 6)% in the three groups, respectively ( p < 0:05 in all three groups). A significant difference between the high and low dose Curosurf groups was found ( p < 0:05), whereas no significant difference was seen between the Curosurf 100 mg group and the Survanta group. The decrease in vascular resistance was compensated by an increase in cardiac output, resulting in a stable mean arterial blood pressure. In conclusion, both Curosurf and Survanta induce a significant decrease in systemic vascular resistance in surfactant-depleted newborn piglets. A more pronounced effect was observed after 200 mg/kg than after 100 mg/kg of Curosurf. 相似文献
36.
Christoffer Bugge Erik Magnus Sæther Odd Terje Brustugun Ivar Sønbø Kristiansen 《Health policy (Amsterdam, Netherlands)》2021,125(8):1100-1107
BackgroundThe broader cost consequences of diseases may be of interest for a wide range of stakeholders. We aimed to estimate all relevant societal costs of cancer and to provide insight into the relative magnitude of the different cost categories.MethodWe used data from eight different health and work-related registries in Norway. Direct, indirect, and intangible costs (value of lost life years) were estimated over a period of one year with a combination of a top-down and a bottom-up costing approach.ResultsThe indirect costs (EUR 1,997 million per year) are almost as high as direct costs (EUR 2,154 million), and the value of lost life years and quality of life represents the greatest cost related to cancer (EUR 18,200 million). In addition, cancer is associated with other costs which are commonly omitted from cost-of-illness analyses, including informal nursing (EUR 306 million), patient time costs (EUR 85 million), and excess costs of using public funds (EUR 439 million). Breast and cervical cancer had relatively high work absenteeism costs, while pancreatic and lung cancer had relatively high production costs due to premature deaths.DiscussionDirect health care costs represent small proportions of the total societal costs of cancer. Costs commonly omitted in cost-of-illness analyses represent a significant cost and should be measured and valued in these analyses. 相似文献
37.
Aina E. Fossum Moen Tone Møller Tannæs Truls Michael Leegaard 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(11):1091-1096
Moen AEF*, Tannæs TM, Leegaard TM. USA300 methicillin‐resistant Staphylococcus aureus (MRSA) in Norway. Community‐associated methicillin‐resistant S. aureus USA300 is known for its ability to disseminate and colonize and the clone has been detected globally. We studied the most populated area in Norway in search for the strain and for signs of endemic establishment. Strain typing techniques such as spa‐, SCCmec‐ and dru‐typing, pulsed‐field gel electrophoresis and detection of USA300 molecular markers, lukS/F‐PV and arcA, were performed. USA300 has been present in the study area since 2003 and has increased in incidence in parallel with the total MRSA incidence. Most USA300 isolates were found in the community, but isolates were also detected in health care institutions. 相似文献
38.
39.
Objectiveto explore experiences with nutrition-related information during routine antenatal care among women of different ethnical backgrounds.Designindividual interviews with seventeen participants were conducted twice during pregnancy. Data collection and analysis were inspired by an interpretative phenomenological approach.Settingparticipants were purposively recruited at eight Mother and Child Health Centres in the area of Oslo, Norway, where they received antenatal care.Participantsparticipants had either immigrant backgrounds from African and Asian countries (n=12) or were ethnic Norwegian (n=5). Participants were pregnant with their first child and had a pre-pregnancy Body Mass Index above 25 kg/m2.Findingsparticipants experienced that they were provided with little nutrition-related information in antenatal care. The information was perceived as presented in very general terms and focused on food safety. Weight management and the long-term prevention of diet-related chronic diseases had hardly been discussed. Participants with immigrant backgrounds appeared to be confused about information given by the midwife which was incongruent with their original food culture. The participants were actively seeking for nutrition-related information and had to navigate between various sources of information.Conclusionsthe midwife is considered a trustworthy source of nutrition-related information. Therefore, antenatal care may have considerable potential to promote a healthy diet to pregnant women. Findings suggest that nutrition communication in antenatal care should be more tailored towards women's dietary habits and cultural background, nutritional knowledge as well as level of nutrition literacy. 相似文献
40.
Elin-Johanne Katle Jan G. Hatlebakk Sverre Steinsvåg 《Current allergy and asthma reports》2013,13(2):218-223
Gastro-esophageal reflux disease (GERD) and chronic rhino-sinusitis (CRS) are prevalent disorders. Coexistence by chance is to be expected in a number of patients. Coexistence due to shared pathogenic mechanisms is controversial. In this paper, we have described the characteristics of GERD and CRS epidemiologically, diagnostically, and pathophysiologically, and reviewed the existing data about a potential role of gastro-esophageal reflux (GER) in the pathogenesis of CRS. A causal link between GERD and CRS has so far not been sufficiently documented. However, some studies do indicate a correlation. Hence, anti-reflux measures should be considered as an option in CRS, particularly in patients where conventional medical and surgical treatment is insufficient. 相似文献