全文获取类型
收费全文 | 1267篇 |
免费 | 92篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 134篇 |
妇产科学 | 86篇 |
基础医学 | 204篇 |
口腔科学 | 33篇 |
临床医学 | 95篇 |
内科学 | 201篇 |
皮肤病学 | 9篇 |
神经病学 | 126篇 |
特种医学 | 18篇 |
外科学 | 108篇 |
综合类 | 29篇 |
一般理论 | 2篇 |
预防医学 | 104篇 |
眼科学 | 11篇 |
药学 | 63篇 |
中国医学 | 1篇 |
肿瘤学 | 127篇 |
出版年
2023年 | 13篇 |
2022年 | 22篇 |
2021年 | 37篇 |
2020年 | 14篇 |
2019年 | 21篇 |
2018年 | 24篇 |
2017年 | 18篇 |
2016年 | 24篇 |
2015年 | 30篇 |
2014年 | 36篇 |
2013年 | 42篇 |
2012年 | 60篇 |
2011年 | 58篇 |
2010年 | 40篇 |
2009年 | 44篇 |
2008年 | 62篇 |
2007年 | 69篇 |
2006年 | 61篇 |
2005年 | 51篇 |
2004年 | 43篇 |
2003年 | 49篇 |
2002年 | 43篇 |
2001年 | 29篇 |
2000年 | 46篇 |
1999年 | 28篇 |
1998年 | 18篇 |
1997年 | 9篇 |
1996年 | 14篇 |
1995年 | 17篇 |
1994年 | 11篇 |
1993年 | 20篇 |
1992年 | 37篇 |
1991年 | 24篇 |
1990年 | 25篇 |
1989年 | 21篇 |
1988年 | 21篇 |
1987年 | 22篇 |
1986年 | 17篇 |
1985年 | 20篇 |
1984年 | 15篇 |
1983年 | 15篇 |
1982年 | 12篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 7篇 |
1977年 | 4篇 |
1976年 | 5篇 |
1974年 | 4篇 |
1973年 | 5篇 |
1967年 | 6篇 |
排序方式: 共有1361条查询结果,搜索用时 46 毫秒
101.
A review of 46 perinatal deaths was conducted using a 1982 to 1985 regional perinatal network database of 6701 delivered postdate (greater than or equal to 42 weeks gestation) infants. Perinatal mortality (6.9 per 1000 births) increased as gestational age advanced beyond 42 weeks, and was higher in young teenagers or mothers with some additional antenatal complications, such as hypertension. Meconium staining of the amniotic fluid, low Apgar scores, low birthweight, congenital malformations, and neonatal complications, including pneumothorax, meconium aspiration, and seizures, were associated with perinatal death. 相似文献
102.
For many years, industry has utilized the concept of human error rates to monitor and minimize human errors in the production process. A consistent quality-controlled product increases consumer satisfaction and repeat purchase of product. Administrative dietitians have applied the concepts of using human error rates (the number of errors divided by the number of opportunities for error) at four hospitals, with a total bed capacity of 788, within a tertiary-care medical center. Human error rate was used to monitor and evaluate trayline employee performance and to evaluate layout and tasks of trayline stations, in addition to evaluating employees in patient service areas. Long-term employees initially opposed the error rate system with some hostility and resentment, while newer employees accepted the system. All employees now believe that the constant feedback given by supervisors enhances their self-esteem and productivity. Employee error rates are monitored daily and are used to counsel employees when necessary; they are also utilized during annual performance evaluation. Average daily error rates for a facility staffed by new employees decreased from 7% to an acceptable 3%. In a facility staffed by long-term employees, the error rate increased, reflecting improper error documentation. Patient satisfaction surveys reveal satisfaction, for tray accuracy increased from 88% to 92% in the facility staffed by long-term employees and has remained above the 90% standard in the facility staffed by new employees. 相似文献
103.
104.
105.
Members of the Collaborative Immunization Initiatives determined the immunization coverage rates for two groups of children
in our clinic: those 7 to 12 months old and those 18 to 23 months old. The Clinic Assessment Software Application from the
Centers for Disease Control and Prevention was used. The immunization rates determined by this method appeared to significantly
underestimate the vaccination coverage rates in our clinic. A review of available charts included in the original sample was
done excluding patients no longer attending our clinic. We found a higher rate of coverage in the same sample and a low rate
of missed opportunities for administering immunizations. The major reason for this discrepancy is overly stringent Clinic
Assessment Software Application inclusion criteria. Additional factors include failure to take into account the wide range
of acceptable ages for administering immunizations and different dosages for different brands of vaccines. Different methods
of calculation may cause as much as a 20% difference in immunization rates for the same or similar population groups. Such
large differences may lead to vastly different responses and interventions. We believe that a central registry is the most
accurate method of determining immunization rates. Until this is widely available and applied, a more accurate measure of
a facility’s immunization effectiveness is the number of missed opportunities for administering immunizations. 相似文献
106.
During an 8-year period, 74 breast cancers were diagnosed in 66 patients 35 years of age and younger who underwent preoperative mammography. Mammograms and clinical data in these women were reviewed retrospectively to evaluate the mammographic findings and the efficacy of mammography. In 58 cases the cancer was detected by means of both clinical examination and mammography; in eight cases, mammography alone enabled readers to find the lesion; in seven cases, the lesion was found by means of clinical examination, but mammograms were negative; and in one case a cancer was found by means of incidental biopsy of the contralateral breast. Although 34 patients (52%) had dense breasts, mammography demonstrated the lesion in 66 cases (89%); the most common mammographic finding was microcalcifications, with or without associated masses (n = 28 [38%]). The authors do not suggest that screening of women younger than 35 years be performed routinely, but they believe that mammography can be valuable in screening young women at high risk for breast cancer or in confirming and suggesting prompt biopsy of a suspicious lesion. 相似文献
107.
108.
109.
BACKGROUND: Research-based standards do not exist for the management of gastric residual volumes from feeding tubes. Withdrawing and returning residual volumes can lead to clogged tubes and exposes patients to possible contamination of the feeding system. However, discarding residual volumes may place patients at risk for electrolyte imbalance and may alter fluid or nutritional balance. OBJECTIVES: To investigate the effects of discarding versus returning gastric residual volumes on body weight, serum electrolyte levels, and the rate of complications associated with tube feeding. METHODS: Thirty-five subjects receiving enteral feedings were recruited from intensive care units at 3 Midwest hospitals and randomized to a discard group or a return group. Eighteen sets of usable data were obtained. RESULTS: Repeated-measures analysis of variance indicated no significant differences between the 2 groups for any of the variables. Complications related to enteral feedings were more common in the return group (n = 8), which had 2 episodes of tube clogging and 1 episode of diarrhea and nausea. None of these complications were experienced by patients in the discard group (n = 10). CONCLUSIONS: Both groups had significant numbers of complications, including a total of 15 episodes, 7 in the discard group and 8 in the return group, of feeding delays due to high gastric residual volumes. Although serum electrolyte levels did not differ significantly between the 2 groups, potassium levels tended to be lower in the discard group. Considerations for the care of critically ill patients with feeding tubes are discussed in light of these findings. 相似文献
110.