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101.
Rigler SK Perera S Redford L Studenski S Brown EF Wallace D Webb M 《Journal of the American Medical Directors Association》2003,4(2):67-73
OBJECTIVE: To characterize changing patterns of antidepressant use in nursing facilities across the urban-rural continuum during the mid-1990s. DESIGN: Retrospective analysis of antidepressant drug codes and demographic/clinical data from the Minimum Data Set (MDS) 1994 to 1997. SETTING: Kansas nursing facilities. PARTICIPANTS: Facility residents aged 65 and older. MEASUREMENTS: We examined (1) admission use and (2) after-admission use for newer and older antidepressants for each year separately, using a 4-stratum system to classify nursing facility location by county, from urban to most rural. Incidence rate ratios were determined for antidepressant use in each stratum using the urban strata as the reference. RESULTS: Remarkable increases in use of newer antidepressants were seen over time in all strata, but use was highest in the urban area. Modest urban-rural gradient effects attenuated over time and were not consistently seen across analyses and years. Tricyclic antidepressant (TCA) use remained largely unchanged over time and at much lower rates than newer agents. However, TCA use was also modestly higher in urban areas. Differences were clearer for use after admission, in contrast with admission use patterns. CONCLUSIONS: Newer antidepressants were rapidly adopted across the urban-rural continuum from 1994 to 1997. Marked increases in both admission and after-admission use of newer antidepressants were seen. Both newer and older antidepressants were used at modestly higher rates in urban areas. Further work is needed to elucidate the patient, prescriber, and facility factors that explain these prescribing patterns. 相似文献
102.
Van Der Hoek W Konradsen F Amerasinghe PH Perera D Piyaratne MK Amerasinghe FP 《International journal of epidemiology》2003,32(2):280-285
BACKGROUND: In Sri Lanka, the major malaria vector Anopheles culicifacies breeds in pools formed in streams and river beds and it is likely that people living close to such breeding sites are at higher risk of malaria than people living further away. This study was done to quantify the importance of house location relative to vector breeding sites for the occurrence of malaria in order to assess the usefulness of this parameter in future malaria risk maps. Such risk maps could be important tools for planning efficient malaria control measures. METHODS: In a group of seven villages in north central Sri Lanka, malaria cases were compared with community controls for distance from house to breeding sites and a number of other variables, including type of housing construction and use of anti-mosquito measures. The presence of An. culicifacies in bedrooms was determined by indoor insecticide spray collections. RESULTS: People living within 750 m of the local stream, which was the established vector-breeding site, were at much higher risk for malaria than people living further away (odds ratio adjusted for confounding by other variables 5.93, 95% CI: 3.50-8.91). Houses close to the stream also had more adult An. culicifacies in the bedrooms. Poor housing construction was an independent risk factor for malaria. CONCLUSIONS: Risk maps of malaria in Sri Lanka can be based on the location of houses relative to streams and rivers that are potential breeding sites for the malaria vector An. culicifacies. A distance of 750 m is suggested as the cut-off point in defining low- and high-risk villages. 相似文献
103.
104.
Sheyda?Ketabchi Daniela?Massi Roberto?Santoro Alessandro?FranchiEmail author 《European archives of oto-rhino-laryngology》2003,260(6):336-340
We describe the case of a 72-year-old woman presenting with a 1-year history of recurrent epistaxis and unilateral progressive nasal obstruction with associated rhinolalia resulting from the presence of a tumor mass occupying two-thirds of the right nasal cavity. Histopathologically, neoplastic cells or "chief cells" were arranged in well-defined nests, which had the classic alveolar or so-called "zellballen" pattern. Immunohistochemical studies highlighted the presence of S-100 protein-positive sustentacular cells located at the periphery of the clusters of chief cells. The chief cells showed a diffuse and intense positivity for neuron-specific enolase and synaptophysin. A diagnosis of paraganglioma was made. The lesion was excised completely and the patient did not develop recurrences or distant metastases after 8 months of follow-up. Paragangliomas arising in the nasal cavity and paranasal sinuses are extremely rare tumors. We report on the clinical, histopathological and immunohistochemical findings of our case and review the cases previously described in the literature. 相似文献
105.
Association between carcinogen-DNA adducts in white blood cells and lung cancer risk in the physicians health study 总被引:16,自引:0,他引:16
Tang D Phillips DH Stampfer M Mooney LA Hsu Y Cho S Tsai WY Ma J Cole KJ Shé MN Perera FP 《Cancer research》2001,61(18):6708-6712
In this matched case-control study nested within the prospective Physicians' Health Study, we evaluated whether DNA damage in blood samples collected at enrollment significantly predicted risk, consistent with our hypothesis that cases have greater biological susceptibility to polycyclic aromatic hydrocarbons and other aromatic tobacco carcinogens. The subjects were 89 cases of primary lung cancer and 173 controls, all males, matched on smoking, age, and duration of follow-up. Aromatic-DNA adducts were measured in WBCs by the nuclease P1-enhanced (32)P-postlabeling method that primarily detects smoking-related adducts. Among current smokers, but not former or nonsmokers, there was a significant increase in mean adduct levels of cases compared with controls (11.04 versus 5.63; P = 0.03). "Healthy" current smokers who had elevated levels of aromatic DNA adducts in WBCs were approximately three times more likely to be diagnosed with lung cancer 1-13 years later than current smokers with lower adduct concentrations (odds ratio, 2.98; 95% confidence interval, 1.05-8.42; P = 0.04). We were not able to discern case-control differences in former smokers and nonsmokers. The findings are of interest because they suggest that individuals who become cases have greater biological susceptibility to tobacco carcinogens, a biological difference, which manifests most clearly while exposure is ongoing. 相似文献
106.
Modern theoretical techniques are employed to provide complete three dimensional structure for the zymogen and activated forms of human coagulation factors IX and IXa. These structures are fully calcium bound and equilibrated in an electrically neutral aqueous environment. The relationship of structure to mutational data is examined. We find that a substantial relative orientational change of the catalytic domain occurs on activation. Also, we find that the electrostatistically dipolar nature of the catalytic domain is substantially modified upon activation, with cleavage of the negatively charged activation peptide leaving behind a largely hydrophobic face in factor IXa. While the backbone atoms of the catalytic residues have little relative movement, nearby loops are found that do move. The presence or absence of these changes likely defines specificity. 相似文献
107.
OBJECTIVE: To report our local experience of the sternoclavicular syndrome and sample the experience of other rheumatologists in the UK. METHODS: We studied case records of 23 patients referred to the Southend rheumatology clinic and data obtained from a postal questionnaire survey of British rheumatologists. RESULTS: We describe 58 cases (20 males and 38 females, mean age 47.2 yr). The disease was unilateral in 40 patients. Shoulder and/or arm pain (38 cases) with limitation of shoulder movements was an important presenting feature; other presenting features were anterior chest wall pain (14 cases) and neck pain (15 cases). Peripheral joint involvement was seen in 12 cases. Skin rash was reported in 12 cases (psoriasis, 6; acne, 2; none had pustulosis). No patients had symptoms or signs of sacroiliitis, and HLA-B27 was negative in 22 out of 23 patients. 99Technetium scintiscanning showed increased uptake in the sternoclavicular region in 31/34 patients (91.1%), but not in the sacroiliac areas. Plain radiographs were abnormal in 18 cases (sclerosis, 9; erosions, 2; soft tissue swelling, 2; bony expansion, 5). CT and/or MRI scans (available in 27 cases) showed erosions in 12 and osteitis in 18. Available histology showed a variable picture, including inflammation, bone erosion, sterile osteomyelitis and fibrosis. The majority of patients (45) were treated with non-steroidal anti-inflammatory drugs: 12 received steroids and 10 received disease-modifying anti-rheumatic drugs (methotrexate, 4; sulphasalazine, 6). Follow-up information was available for 38 patients, of whom 14 became asymptomatic and 24 had chronic disease with intermittent flares. CONCLUSION: Sternoclavicular disease is not uncommon in the UK. It can present with pain in the shoulder, neck or anterior chest wall, and may be underdiagnosed. Our results do not show a link with acne or pustulosis. Features of spondyloarthropathies, such as sacroiliitis and HLA-B27 positivity, were rare in this survey. 相似文献
108.
Wieslaw Jedrychowski Alek Sander Galas Elzbieta Flak Ryszard Jacek Agnieszka Penar John Spengler Frederica P. Perera 《Early child development and care》2007,177(4):369-381
The main purpose of our study was to assess the effects of prenatal tobacco smoke on respiratory symptoms and on doctor consultations in a birth cohort of 445 infants who had no smoking mothers and who had no postnatal exposure to environmental tobacco smoke (ETS). Before and after delivery, questionnaires and interviews with mothers were administered to solicit information on prenatal and postnatal ETS exposure. Newborns were followed-up over six months of life, and respiratory outcomes such as runny or stuffed nose, cough with or without cold, difficult (puffed) breathing, wheezing or whistling in the chest irrespective of respiratory infection were considered. In addition, medical visits related to the occurrence of respiratory symptoms were recorded for each child over a six-month study period. In the multivariate Poisson regression analysis, a set of potential confounders has been taken into account such as gender of child, season of birth, gestational age, maternal education, maternal atopy, presence of moulds in households and prenatal level of personal exposure to fine particles. The adjusted rate ratio (RR) estimated for the occurrence of episodes of running nose was significantly higher in infants exposed to prenatal ETS (1.40; 95% confidence interval [CI]: 1.11-1.68) and the corresponding RR estimates for cough, difficult breathing and wheezing were 1.49 (95% CI: 1.15-1.93), 1.96 (95% CI: 1.22-3.16) and 5.12 (95% CI: 2.86-9.16). The rate ratios of doctor consultations attributable to prenatal ETS because of cough was 1.94 (95% CI: 1.49-2.54). The risk estimate for consultations due to difficult breathing was 2.77 (95% CI: 1.76-4.36), and that for wheezing was 5.86 (95% CI: 3.56-9.64). The data strongly support the view about the impact of the in-utero effect of passive smoking on children's respiratory health. Higher utilization rates of doctor consultations in infants attributable to prenatal ETS exposure demand the revision of public health policy, which should be focused also on cessation of smoking practices by all household members during and after the pregnancy period. 相似文献
109.
Hua Zhu Ajay Kumar Jerome Ozkan Rani Bandara Aidong Ding Indrani Perera Peter Steinberg Naresh Kumar William Lao Stefani S Griesser Leanne Britcher Hans J Griesser Mark D P Willcox 《Optometry and vision science》2008,85(5):292-300
PURPOSE: To examine the ability of contact lenses coated with fimbrolides, inhibitors of bacterial quorum sensing, to prevent microbial adhesion and their safety during short-term clinical assessment. METHODS: A fimbrolide was covalently attached to commercially available high Dk contact lenses. Subsequently Pseudomonas aeruginosa, Staphylococcus aureus, Serratia marcescens, or Acanthamoeba sp. were added to the lenses and control uncoated contact lenses. Lenses plus microbes were incubated for 24 h, then washed thoroughly to remove non-adherent microbes. Lenses were macerated and resulting slurry plated onto agar plates. After appropriate incubation, the numbers of colony forming units of bacteria (or numbers of Acanthamoeba trophozoites measured using a hemocytometer) from fimbrolide-coated and uncoated lenses were examined. A Guinea Pig model of lens wear was used to assess the safety of lenses worn on a continuous basis for 1 month. In a separate study, 10 subjects wore fimbrolide-coated lenses for 24 h. The responses of the Guinea Pigs and human volunteers to the lenses were assessed by slit lamp examination. RESULTS: The fimbrolides-coated lenses reduced the adhesion of all bacterial strains tested, with reductions occurring of between 67 and 92%. For Acanthamoeba a reduction of 70% was seen. There were no significant differences in ocular responses to fimbrolide-coated lenses compared with controls in either the 1 month animal model or overnight human trial. CONCLUSIONS: Fimbrolide-coated lenses show promise as an antibacterial and anti-acanthamoebal coating on contact lenses and appear to be safe when worn on the eye in an animal model. 相似文献
110.
Anemia is a common complication of autonomic failure and reduced red blood cell mass may contribute to the orthostatic hypotension of these patients. We investigated whether treatment with recombinant erythropoietin improves anemia and increases blood pressure in patients with primary autonomic failure. Three patients with multiple system atrophy and autonomic failure and one with pure autonomic failure were studied. All patients had normocytic normochromic anemia and low (n = 2) or normal (n = 2) serum levels of erythropoietin. Treatment with erythropoietin, 4000 U subcutaneously biweekly for 6 weeks, increased hematocrit and blood pressure in all patients. Hematocrit increased from 33.9 ± 0.7 to 44.3 ± 1.4%, blood pressure in supine position increased from 150 ± 8/87 ± 8 (systolic/diastolic; mean ± SD) to 166 ± 25/92 ± 12 mmHg, and after 3 min in the head-up tilt position from 86 ± 21/47 ± 15 to 102 ± 23/63 ± 12 mmHg, (p < 0.05). All patients reported improvement in orthostatic symptoms and increased tolerance to standing. The study shows that treatment with erythropoietin improves anemia, increases blood pressure and ameliorates orthostatic hypotension in patients with primary autonomic failure. 相似文献