全文获取类型
收费全文 | 1735篇 |
免费 | 113篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 83篇 |
妇产科学 | 14篇 |
基础医学 | 239篇 |
口腔科学 | 18篇 |
临床医学 | 130篇 |
内科学 | 309篇 |
皮肤病学 | 35篇 |
神经病学 | 273篇 |
特种医学 | 132篇 |
外科学 | 228篇 |
综合类 | 110篇 |
一般理论 | 2篇 |
预防医学 | 109篇 |
眼科学 | 17篇 |
药学 | 81篇 |
中国医学 | 1篇 |
肿瘤学 | 77篇 |
出版年
2022年 | 13篇 |
2021年 | 28篇 |
2020年 | 18篇 |
2019年 | 12篇 |
2018年 | 28篇 |
2017年 | 27篇 |
2016年 | 35篇 |
2015年 | 38篇 |
2014年 | 48篇 |
2013年 | 57篇 |
2012年 | 68篇 |
2011年 | 74篇 |
2010年 | 62篇 |
2009年 | 71篇 |
2008年 | 77篇 |
2007年 | 64篇 |
2006年 | 65篇 |
2005年 | 59篇 |
2004年 | 47篇 |
2003年 | 43篇 |
2002年 | 56篇 |
2001年 | 56篇 |
2000年 | 58篇 |
1999年 | 48篇 |
1998年 | 63篇 |
1997年 | 49篇 |
1996年 | 45篇 |
1995年 | 32篇 |
1994年 | 38篇 |
1993年 | 26篇 |
1992年 | 39篇 |
1991年 | 37篇 |
1990年 | 33篇 |
1989年 | 32篇 |
1988年 | 38篇 |
1987年 | 53篇 |
1986年 | 25篇 |
1985年 | 24篇 |
1984年 | 20篇 |
1983年 | 19篇 |
1982年 | 22篇 |
1981年 | 12篇 |
1980年 | 8篇 |
1979年 | 13篇 |
1978年 | 13篇 |
1977年 | 12篇 |
1976年 | 12篇 |
1975年 | 7篇 |
1974年 | 9篇 |
1972年 | 5篇 |
排序方式: 共有1864条查询结果,搜索用时 31 毫秒
91.
92.
Mitchell L. Jones Christopher J. Martoni Sandeep Tamber Mathieu Parent Satya Prakash 《Food and chemical toxicology》2012
Probiotic organisms have shown promise in treating diseases. Previously, we have reported on the efficacy of microencapsulated Lactobacillus reuteri NCIMB 30242 in a yogurt formulation at lowering serum cholesterol levels in otherwise healthy hypercholesterolemic adults. This study investigates the safety and toxicology of oral ingestion of microencapsulated L. reuteri NCIMB 30242 in a yogurt formulation. A randomized group of 120 subjects received a dose of 5 × 1010 CFU microencapsulated L. reuteri NCIMB 30242 in yogurt (n = 59) or placebo yogurt (n = 61) twice/day for 6 weeks. Clinical chemistry and hematological parameters of safety were analyzed. Fecal samples were collected at these time points for the analysis of deconjugated bile acids. The frequency, duration and intensity of adverse events (AEs) and clinical significance of safety parameters were recorded for both groups. No clinically significant differences between the probiotic yogurt and placebo yogurt treated groups were detected in either the blood clinical chemistry or hematology results and there was no significant increase in fecal deconjugated bile acids (P > 0.05) between treated and control groups. The frequency and intensity of AEs was similar in the two groups. These results demonstrate the safe use of this formulation in food. 相似文献
93.
AB Rossi JJ Leyden AS Pappert A Ramaswamy A Nkengne R Ramaswamy M Nighland 《Journal of the European Academy of Dermatology and Venereology》2011,25(4):398-402
Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method. 相似文献
94.
OBJECTIVES: The purpose of this study was to determine whether vicarious experience, in which former patients exemplify the active lives they are leading, reduces anxiety and increases self-efficacy expectation and self-reported activity in patients after cardiac surgery. DESIGN: A randomized, controlled trial was used to evaluate an intervention that linked volunteers who had recovered from cardiac surgery in dyadic support with patients about to undergo similar surgery. The linking was achieved by means of visits during the hospitalization and recovery period. SUBJECTS: Fifty-six first-time male patients undergoing coronary artery bypass graft (CABG) surgery, with a mean age of 56.5 years, were randomly assigned to an experimental (n = 27) or control group (n = 29). Outcome Measures: Anxiety was measured at 48 hours and 24 hours before surgery, and again at 5 days and 4 weeks after surgery. Self-efficacy expectation and self-reported activity were both evaluated at 5 days and 4 weeks after surgery. RESULTS: Only the experimental group showed a significant decrease in anxiety during hospitalization. At all measurement times after the first intervention, the experimental group reported significantly lower levels of anxiety compared with the control group. The experimental group reported significantly higher levels of self-efficacy expectation and self-reported activity for general activities, walking, and climbing stairs evaluated at 5 days, and for general activities at 4 weeks after surgery. CONCLUSIONS: Vicarious experience provided through dyadic support is effective in helping patients undergoing cardiac surgery cope with surgical anxiety and in improving self-efficacy expectations and self-reported activity after surgery. Dyadic support is a valuable tool for recovery from cardiac surgery that needs to be maintained and explored through nursing practice and research. 相似文献
95.
Sevilla R Sejas E Zalles L Belmonte G Chevalier P Parent G Katherine H Kolsteren P 《Santé (Montrouge, France)》2000,10(2):97-102
The "CLAPSEN" approach was developed at the Hospital Materno Infantil German Urquidi in Cochabamba, to provide a global response for the study and treatment of childhood malnutrition. "CLAPSEN" is short for Clinical, Laboratory, Anthropometry, Psychology, Sociology, Nursing (Enfermera in Spanish) and Nutritional care. Most of the malnourished children admitted to Cochabamba Hospital are from poor families, more than three quarters of whom have only recently arrived in the city. Acute malnutrition is just one of the manifestations of a generally unfavorable environment. Malnutrition should not be considered as a simple deficiency in energy, protein or micronutrients, but rather as a multi-deficiency syndrome, also involving a lack of basic health and social care. This study demonstrates that malnourished children display a considerable degree of psychological retardation and of immune system depression. After five weeks of rehabilitation, the children were considered to have recuperated physically, as assessed by anthropometry, but not psychologically, as assessed by the adapted Dewer Score, or immunologically, as shown by the size of the thymus or the extent of maturation of lymphocytes. This strategy was not designed as a long-term approach for treating malnutrition, but rather as a research project to characterize the children arriving at the hospital, to determine the reasons for their malnutrition and to identify strategies that could be implemented earlier by health centers of social services, to prevent deterioration in the condition of these children to severe malnutrition requiring hospital admission. We believe that, in this Latin American context, in which the rate of acute malnutrition is low, the hospital should continue to be involved in the treatment of severely malnourished children with associated diseases. The child's stay in hospital should be short and once the child has recovered clinically, he should be sent home. In light of the observed levels of social deprivation, psychosocial and immune deficits, there appears to be a need for continued support for the family, to ensure the full recovery of the child and to prevent relapses. 相似文献
96.
Occupational risk factors for renal cell carcinoma in Montreal 总被引:4,自引:0,他引:4
BACKGROUND: Little is known about the role of workplace exposures on the risk of renal cell cancer. METHODS: A population-based case-control study was undertaken in Montreal to assess the association between hundreds of occupational circumstances and several cancer sites, including the kidney. A total of 142 male patients with pathologically confirmed renal cell carcinoma, 1900 controls with cancer at other sites and 533 population-based controls were interviewed. Detailed job histories and relevant data on potential confounders were obtained. A group of chemists-hygienists evaluated each job reported and translated them into a history of occupational exposures using a checklist of 294 substances. Multivariate logistic regression models using either population, cancer controls, or a pool of both groups were used to estimate odds ratios. RESULTS: There were some indications of excess risks among printers, nursery workers (gardening), aircraft mechanics, farmers, and horticulturists, as well as in the following industries: printing-related services, defense services, wholesale trade, and retail trade. Notwithstanding the low precision of many of the odds ratio estimates, the following workplace exposures showed some evidence of excess risk: chromium compounds, chromium (VI) compounds, inorganic acid solutions, styrene-butadiene rubber, ozone, hydrogen sulphide, ultraviolet radiation, hair dust, felt dust, jet fuel engine emissions, jet fuel, aviation gasoline, phosphoric acid and inks. CONCLUSIONS: For most of these associations there exist no, or very little, previous data. Some associations provide suggestive evidence for further studies. 相似文献
97.
A Papadopoulou MO Rawashdeh GA Brown AS McNeish IW Booth 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(1):79-83
The short- and long-term effects of an elemental diet in children with acute Crohn's disease were compared with those of prednisolone in historical controls. Clinical remission was induced in 25 of 30 and in 18 of 28 episodes treated for six weeks with an elemental diet and prednisolone. Patients with proximal disease had longer remission after treatment with an elemental diet (p < 0.05) than did patients with colonic disease after treatment with prednisolone (p < 0.01). Disease activity index score improved in both groups compared with the pretreatment scores (p < 0.05). However, the improvement in the elemental diet group was significantly better than in the prednisolone group (p < 0.001). Changes in linear growth were better after treatment with an elemental diet compared with steroids (p < 0.001). Serum albumin and haematocrit concentrations all improved significantly in the children treated with an elemental diet (p < 0.001) but not in those treated with steroids. Thus an elemental diet was better than prednisolone in proximal disease and confirmed improved growth and nutritional status. 相似文献
98.
IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):544-549
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty. 相似文献
99.
Association of hepatitis B virus infection with other sexually transmitted infections in homosexual men. Omega Study Group 下载免费PDF全文
Remis RS Dufour A Alary M Vincelette J Otis J Mâsse B Turmel B LeClerc R Parent R Lavoie R 《American journal of public health》2000,90(10):1570-1574
OBJECTIVES: This study determined the prevalence and factors associated with hepatitis B virus (HBV) infection among men who have sex with men. METHODS: At the baseline visit of an HIV study among men who have sex with men, we asked about HBV vaccination status and tested for HBV markers. RESULTS: Of 625 subjects, 48% had received at least 1 dose of HBV vaccine. Of 328 unvaccinated men, 41% had 1 or more HBV markers. HBV prevalence increased markedly with age and was associated with many sexual and drug-related behaviors. In a multivariate model, 7 variables were independently associated with HBV infection: ulcerative sexually transmitted diseases (odds ratio [OR] = 10.1; 95% confidence interval [CI] = 2.6, 54); injection drug use (OR = 5.2; 95% CI = 1.2, 26); gonorrhea or chlamydia (OR = 4.0; 95% CI = 1.9, 8.9); sexual partner with HIV/AIDS (OR = 3.6; 95% CI = 1.8, 7.1); 50 or more casual partners (OR = 3.4; 95% CI = 1.6, 7.1); received money for sex (OR = 3.0; 95% CI = 1.2, 7.8); and 20 or more regular partners (OR = 2.5; 95% CI = 1.1, 6.1). CONCLUSIONS: In Montreal, men who have sex with men are at risk for HBV infection, but a substantial proportion remain unvaccinated; new strategies are required to improve coverage. Men who have sex with men and who have a sexually transmitted infection, especially a genito-ulcerative infection, appear to be at particularly high risk for HBV infection. 相似文献
100.
J. Gaudin C. Le Treguilly P. Parent H. Le Guern J. J. Chabaud G. Boog B. Jehannin 《Pediatric surgery international》1988,3(2-3):158-164
Twelve cases of ovarian cysts are reported. The diagnosis was made antenatally by ultrasound scan. The authors consider the ultrasonic images of these cysts and signs of in-utero torsion, the antenatal and postnatal evolution, the pathological findings at surgery, and the histological results for six children that were operated. A review of the literature enables us to describe the possible complications in the evolution of this tumor and to discuss the perinatal management of the ovarian cyst, which depends on the appearance and diameter of the cyst and on its evolution.
Offprint requests to: J. Gaudin 相似文献