全文获取类型
收费全文 | 99962篇 |
免费 | 42443篇 |
国内免费 | 95篇 |
专业分类
耳鼻咽喉 | 1734篇 |
儿科学 | 5026篇 |
妇产科学 | 1133篇 |
基础医学 | 18802篇 |
口腔科学 | 5910篇 |
临床医学 | 14517篇 |
内科学 | 27963篇 |
皮肤病学 | 7911篇 |
神经病学 | 15293篇 |
特种医学 | 2926篇 |
外科学 | 16529篇 |
综合类 | 168篇 |
一般理论 | 33篇 |
预防医学 | 6211篇 |
眼科学 | 1655篇 |
药学 | 7000篇 |
中国医学 | 1102篇 |
肿瘤学 | 8587篇 |
出版年
2023年 | 176篇 |
2022年 | 400篇 |
2021年 | 1914篇 |
2020年 | 5378篇 |
2019年 | 11309篇 |
2018年 | 10707篇 |
2017年 | 11817篇 |
2016年 | 12513篇 |
2015年 | 12453篇 |
2014年 | 12592篇 |
2013年 | 13308篇 |
2012年 | 5746篇 |
2011年 | 5708篇 |
2010年 | 9812篇 |
2009年 | 6055篇 |
2008年 | 3369篇 |
2007年 | 2360篇 |
2006年 | 2230篇 |
2005年 | 1962篇 |
2004年 | 1810篇 |
2003年 | 1763篇 |
2002年 | 1729篇 |
2001年 | 1200篇 |
2000年 | 1096篇 |
1999年 | 717篇 |
1998年 | 266篇 |
1997年 | 245篇 |
1996年 | 192篇 |
1995年 | 187篇 |
1994年 | 169篇 |
1993年 | 143篇 |
1992年 | 312篇 |
1991年 | 279篇 |
1990年 | 221篇 |
1989年 | 242篇 |
1988年 | 213篇 |
1987年 | 173篇 |
1986年 | 196篇 |
1985年 | 183篇 |
1984年 | 148篇 |
1983年 | 132篇 |
1982年 | 95篇 |
1981年 | 101篇 |
1980年 | 67篇 |
1979年 | 104篇 |
1978年 | 91篇 |
1976年 | 60篇 |
1975年 | 65篇 |
1973年 | 61篇 |
1972年 | 59篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
62.
The results of the multiple regression and correlation analysis between perinatal mortality and social and health care variables in Spanish provinces between 1975 and 1979 are presented. Although the perinatal mortality rates of Spanish provinces correlate significantly with a series of socioeconomic variables (family income available per capita, percentage of active population in primary sector, educational level of women at childbearing age) and health care variables (active obstetricians per 1000 live births and active pediatricians per 1000 live births), the multiple correlation and regression analysis has shown that the most important variable is the family income available per capita: 44% of the variability of perinatal mortality in Spanish provinces can be accounted for by this factor. By regression analysis, it is also possible to predict a decrease of 0.065 points in perinatal mortality for every additional 1000 pesetas in the family income available per capita. 相似文献
63.
Prospective study of antigenemia,plasma viremia and lymphocytic viremia in HIV-infected hemophiliacs
S. Melón Garcia M. de Oña Navarro C. Rodriguez Pinto M. Fernández Urgellés A. Martinez Gutierrez P. de la Iglesia F. J. Mendez García 《European journal of clinical microbiology & infectious diseases》1995,14(5):400-405
A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05). 相似文献
64.
Access to food and the amount consumed were investigated within a group of 45 children aged 33 to 60 months, among whom growth stunting was common. Children were observed throughout 1 day; all foods offered and consumed were weighed, and food-related behaviors noted. Children ate frequently, at least 2 meals and an average of 7.4 +/- 2.6 snacks daily. Children had access to 2029 +/- 575 kcal (8493 +/- 2407 kJ) yet only consumed 1528 +/- 343 kcal (6396 +/- 1436 kJ) daily; thus food availability was not restricting intake. A higher proportion of snacks than meals (85 per cent vs. 71 per cent) was consumed. Children requested foods frequently (x = 9.2 +/- 4.3) and 76 per cent of requests were fulfilled. Neither amount of accessible food nor amount consumed differed by age, gender, or socioeconomic status. The importance of the child's role in determining food intake, and of snacking to overall food consumption, was demonstrated. 相似文献
65.
In every Radiation Oncology Department there is a group of patients referred for curative radiotherapy and within this group of patients there is a subset of patients who present the most difficult of treatment scenarios, maximum tumor dose and minimum spinal cord dose. The case to be presented involved the use of a head and neck five field technique of which three fields were treated isocentrically with the remaining two fields being electron boosts. It is from these patients that we extend to the maximum our planning capabilities. 相似文献
66.
The present study provides an analysis of the effects of particular patterns of teacher respose to students' entries in dialogue journals. It extended on previous research related to teacher-student instructional discourse by concentrating on written, teacher-student interactions. Second grade children who were participating in a daily dialogue journal activity were randomly subjected to two types of response patterns by their teacher. The results show that a teacher's elaborative responses to student journal entries directly lead to increase written output by students coupled with a distinct process #ophigher order#cp orientation of student entries. 相似文献
67.
BACKGROUND: Assessment of inpatient asthma management has generally been limited to urban settings, including Chicago, which is known for its high asthma morbidity and mortality. Previously published data have been based on survey methodology. The Suburban Asthma Consortium (SAC) sought to obtain patient-based data unique to the Chicago suburbs to improve asthma care in those areas. OBJECTIVE: To evaluate current inpatient asthma management based on the 1997 National Asthma Education and Prevention Program (NAEPP). DESIGN: Retrospective chart review of all hospitalized patients 3-65 years bearing asthma-related ICD-9 codes for fiscal year 2002 in community, nonteaching hospitals in Chicago suburbs. RESULTS: Nine hundred two cases were submitted from seven hospitals. The majority ( > or = 75%) received inhaled bronchodilators, systemic steroids, oxygen and pulse oximetry. Antibiotic use (67%), chest radiography (85%), complete blood count (77%), and electrolytes (59%) appeared excessive in view of NAEPP recommendations. Peak flow monitoring (PFM) was recorded on admission in 45% of patients 5 years old and older; 52% had PFM during hospitalization. Thirty-eight percent of patients were taking ICS prior to admission; of those not on ICS, only 12% were newly diagnosed asthmatics. Overall, 51% of patients were discharged with ICS. Patients were more likely to receive ICS at discharge if they had required intensive care (ICU), had been on ICS prior to admission, were referred to an asthma specialist while hospitalized, or were insured. Patients with Medicare/Medicaid (MC/MA) had more repeat emergency visits and hospitalizations, longer lengths of stay, and received less ICS at discharge. Depending on the parameter, 41% or less patients received discharge planning education and were not more likely to have received education if in the ICU. Results ranged significantly between hospitals for most parameters (p < 0.05 or less). CONCLUSION: Study subjects received appropriate acute therapy and oxygen monitoring, but there was a divergence from NAEPP recommendations regarding PFM, ICS use, antibiotics, and laboratory evaluation. Patients receiving MC/MA experienced higher morbidity and received less ICS. Discharge asthma education was suboptimal for most hospitals. Most parameters demonstrated significantly wide practice variations between hospitals. Peak flow monitoring and patient education findings differed significantly from those in survey-conducted studies. 相似文献
68.
Telma L F Gouveia Julia F O Paim Rita C Pavanello Mayana Zatz Mariz Vainzof 《Diagnostic molecular pathology》2006,15(2):95-100
Sarcoglycanopathies (SGpathies) are highly frequent among severely affected limb-girdle muscular dystrophy patients. On the basis of the findings of 5 common mutations in the 4 sarcoglycan (SG) genes in the Brazilian population, we standardized a multiplex polymerase chain reaction-single-strand conformation polymorphism methodology for their concomitant analysis in DNA samples. The test was able to confirm the diagnosis in about 63% of new patients with a suspected SGpathy and was particularly important in patients in advanced stages of the disease, when obtaining a muscle biopsy for analysis may be very difficult. As common mutations have been described in several countries, this multiplex analysis could be useful for the diagnosis of SGpathies if established according to the most prevalent mutations in each population. Besides, even though the disorder studied is rare, the technique could be broadly applicable to other genes and disorders. 相似文献
69.
70.
Andrea von Berg Renate Engelstätter Predrag Minic Miodrag Sréckovic Maria Luz Garcia Garcia Tadeusz Lato Jan H. Vermeulen Stefan Leichtl Stefan Hellbardt Thomas D. Bethke 《Pediatric allergy and immunology》2007,18(5):391-400
Ciclesonide is an onsite-activated inhaled corticosteroid (ICS) for the treatment of asthma. This study compared the efficacy, safety and effect on quality of life (QOL) of ciclesonide 160 microg (ex-actuator; nominal dose 200 microg) vs. budesonide 400 microg (nominal dose) in children with asthma. Six hundred and twenty-one children (aged 6-11 yr) with asthma were randomized to receive ciclesonide 160 microg (ex-actuator) once daily (via hydrofluoroalkane metered-dose inhaler and AeroChamber Plus spacer) or budesonide 400 microg once daily (via Turbohaler) both given in the evening for 12 wk. The primary efficacy end-point was change in forced expiratory volume in 1 s (FEV1). Additional measurements included change in daily peak expiratory flow (PEF), change in asthma symptom score sum, change in use of rescue medication, paediatric and caregiver asthma QOL questionnaire [PAQLQ(S) and PACQLQ, respectively] scores, change in body height assessed by stadiometry, change in 24-h urinary cortisol adjusted for creatinine and adverse events. Both ciclesonide and budesonide increased FEV1, morning PEF and PAQLQ(S) and PACQLQ scores, and improved asthma symptom score sums and the need for rescue medication after 12 wk vs. baseline. The non-inferiority of ciclesonide vs. budesonide was demonstrated for the change in FEV1 (95% confidence interval: -75, 10 ml, p = 0.0009, one-sided non-inferiority, per-protocol). In addition, ciclesonide and budesonide showed similar efficacy in improving asthma symptoms, morning PEF, use of rescue medication and QOL. Ciclesonide was superior to budesonide with regard to increases in body height (p = 0.003, two-sided). The effect on the hypothalamic-pituitary-adrenal axis was significantly different in favor of ciclesonide treatment (p < 0.001, one-sided). Both ciclesonide and budesonide were well tolerated. Ciclesonide 160 microg once daily and budesonide 400 microg once daily were effective in children with asthma. In addition, in children treated with ciclesonide there was significantly less reduction in body height and suppression of 24-h urinary cortisol excretion compared with children treated with budesonide after 12 wk. 相似文献