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51.
OBJECTIVES: We investigated fatal occupational injury rates in the United States by race and Hispanic ethnicity during the period 1990-1996. METHODS: Fatalities were identified by means of the national traumatic occupational fatalities surveillance system. Fatal occupational injury rates were calculated by race/ethnicity and region using US-census-based workforce estimates. RESULTS: Non-Hispanic Black men in the South had the highest fatal occupational injury rate (8.5 per 100000 worker-years), followed by Hispanic men in the South (7.9 per 100000 worker-years). Fatal injury rates for Hispanic men increased over the study period, exceeding rates for non-Hispanic Black men in the latter years of observation. CONCLUSIONS: These data suggest a change in the demographics of fatal occupational injuries in the United States. Hispanic men in the South appear to be emerging as the group with the nation's highest unintentional fatal occupational injury rate.  相似文献   
52.
BACKGROUND: Occupational fatal injury rate studies are often based upon uncertain and variable data. The numerator in rate calculations is often obtained from surveillance systems that can understate the true number of deaths. Worker-years, the denominator in many occupational rate calculations, are frequently estimated from sources that exhibit different amounts of variability. METHODS: Effects of these data limitations on analyses of trends in occupational fatal injuries were studied using computer simulation. Fatality counts were generated assuming an undercount. Employment estimates were produced using two different strategies, reflecting either frequent but variable measurements or infrequent, precise estimates with interpolated estimates for intervening years. Poisson regression models were fit to the generated data. A range of empirically motivated fatality rate and employment parameters were studied. RESULTS: Undercounting fatalities resulted in biased estimation of the intercept in the Poisson regression model. Relative bias in the trend estimate was near zero for most situations, but increased when a change in fatality undercounting over time was present. Biases for both the intercept and trend were larger when small employment populations were present. Denominator options resulted in similar rate and trend estimates, except where the interpolated method did not capture true trends in employment. CONCLUSIONS: Data quality issues such as consistency of conditions throughout the study period and the size of population being studied affect the size of the bias in parameter estimation.  相似文献   
53.
54.
Family caregivers of older adults with progressive dementia (e.g., Alzheimer's disease) are faced with a variety of emotional and behavioral difficulties, such as dealing with persistent, repetitive questions, managing agitation and depression, and monitoring hygiene and self-care activities. Although professional and governmental organizations have called for the creation of community-based education and support programs, most dementia caregivers continue to receive little or no formal instruction in responding effectively to these challenges. The current paper describes the development and implementation of Alzheimer's Caregiver Support Online, a Web- and telephone-based education and support network for caregivers of individuals with progressive dementia. Lessons learned from the first two years of this state-supported initiative are discussed, followed by the findings of a Robert Wood Johnson Foundation-funded strategic marketing initiative and an initial program evaluation of AlzOnline's Positive Caregiving classes. Finally, clinical implications and future directions for program development and evaluation research are proposed.  相似文献   
55.
Recent studies have shown that hypertonic saline (HS) resuscitation can reduce hemorrhage-induced lung damage by preventing neutrophil activation. In this study, we examined whether this protective effect can be improved by increasing the HS dose used for resuscitation. The protective effect of two HS doses was tested in a mouse model of hemorrhagic shock. BALB/c mice were bled to a mean arterial blood pressure of 35 +/- 5 mmHg for 1 h. Then the animals were resuscitated with lactated Ringer's (LR) or with HS (7.5% NaCl) at doses of 4 mL/kg or 6 mL/kg body weight, sacrificed after 24 h, and lung tissue samples were collected. Evidence of lung injury was evaluated morphologically by scoring histology specimens in a blinded fashion. In a separate set of mice, plasma Na+ and osmolarity were determined 15 min after resuscitation. Resuscitation of hemorrhaged mice with 4 and 6 mL/kg HS increased plasma Na+ concentrations by 5 and 11 mM, respectively. LR treatment reduced plasma Na+ concentrations by 6 mM and resulted in a lung injury score of 6.1 +/- 0.8, accompanied by focal thickening of alveolar membranes, congestion, pulmonary edema, and interstitial and intra-alveolar neutrophil infiltration. HS at 4 mL/kg decreased focal thickening, congestion, pulmonary edema, and neutrophil infiltration, and the injury score to 3.8 +/- 0.9, which was not significantly different from controls (3.6 +/- 0.8), and lung damage was lowest in animals that received 6 mL/kg HS (2.5 +/- 0.2, P < 0.005 vs. LR). Lung damage scores inversely correlated with plasma Na+ concentrations (r > 0.9999). Our data suggest that the protective effect of HS may be a function of the plasma Na+ concentration and that HS at 6 mL/kg is at least equally effective in reducing hemorrhage-induced lung damage compared to the more commonly used HS dose of 4 mL/kg.  相似文献   
56.
Homicide on the job: workplace and community determinants   总被引:3,自引:0,他引:3  
Homicide is the second leading cause of death on the job for workers in the United States. To identify workplace-level predictors of homicide risk, a case-control study of worker killings in North Carolina in 1994-1998 was conducted. Workplaces were the units of analysis: case workplaces (n = 105) were those where a worker was killed during the study period, while controls (n = 210) were a density sample of North Carolina workplaces, matched on time and industry sector. Potential risk and protective factors were assessed in telephone interviews with workplace managers. Associations were measured by the exposure odds ratio and 95% confidence interval, estimated via conditional logistic regression. Characteristics associated with notably higher risk included being at the current location for 2 years or less (odds ratio (OR) = 5.3, 95% confidence interval (CI): 2.2, 12.6), having only one worker (OR = 2.9, 95% CI: 1.2, 7.2), and having night (OR = 4.9, 95% CI: 2.7, 8.8) or Saturday (OR = 4.2, 95% CI: 1.9, 9.2) hours. Workplaces with only male employees (OR = 3.1, 95% CI: 1.5, 6.5) or with African-American or Asian employees were also more likely to experience a killing. While few of the preceding risk factors are directly modifiable through workplace interventions, it is important to identify them before developing or evaluating preventive measures.  相似文献   
57.
We retrospectively reviewed 13 patellar tendon repairs done over 32 months at a tertiary care, military medical center. Early mobilization was initiated within 2 weeks postoperatively. Clinical and functional results were statistically examined with relation to age, timing of surgery, length of follow-up, quadriceps atrophy, extensor lag, patella position, and time to full duty. At an average of 24 months' follow-up, six patients (46%) had thigh girth atrophy, and one patient (8%) had an extensor lag >5 degrees. Mean Lysholm score was 84 (range, 57 to 100). Maximum postoperative Tegner activity scores averaged 7.1 (range, 5 to 10). Clinical results classified five cases as excellent, three good, three fair, and two poor. Functional results classified three cases as excellent, four good, two fair, and four poor. Time to return to duty averaged 13 months. Our results suggest that adequate extensor function can be restored after primary repair and immediate motion therapy.  相似文献   
58.
There are 183 zoos and aquariums accredited by the American Zoo and Aquarium Association and scores of smaller, nonaccredited zoos in the U.S. Thousands of individuals work at these zoos in many different roles. Likewise, most counties and many larger cities employ animal control officers and have animal shelters. The authors discuss the numerous hazards encountered by animal control officers as well as employees of zoo and aquarium facilities. Suggested protocols for ensuring a safe workplace are presented. However, a thorough industrial hygiene and safety inspection should be performed on a regular basis, as additional protocols may be needed periodically.  相似文献   
59.

Background

The contribution of BRCA1 and BRCA2 to the incidence of male breast cancer (MBC) in the United Kingdom is not known, and the importance of these genes in the increased risk of female breast cancer associated with a family history of breast cancer in a male first-degree relative is unclear.

Methods

We have carried out a population-based study of 94 MBC cases collected in the UK. We screened genomic DNA for mutations in BRCA1 and BRCA2 and used family history data from these cases to calculate the risk of breast cancer to female relatives of MBC cases. We also estimated the contribution of BRCA1 and BRCA2 to this risk.

Results

Nineteen cases (20%) reported a first-degree relative with breast cancer, of whom seven also had an affected second-degree relative. The breast cancer risk in female first-degree relatives was 2.4 times (95% confidence interval [CI] = 1.4–4.0) the risk in the general population. No BRCA1 mutation carriers were identified and five cases were found to carry a mutation in BRCA2. Allowing for a mutation detection sensitivity frequency of 70%, the carrier frequency for BRCA2 mutations was 8% (95% CI = 3–19). All the mutation carriers had a family history of breast, ovarian, prostate or pancreatic cancer. However, BRCA2 accounted for only 15% of the excess familial risk of breast cancer in female first-degree relatives.

Conclusion

These data suggest that other genes that confer an increased risk for both female and male breast cancer have yet to be found.
  相似文献   
60.
Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.  相似文献   
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