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101.
Recent studies have suggested that Epstein-Barr virus (EBV) may play a role in the aetiology of Hodgkin's disease. To determine the role of EBV in childhood Hodgkin's disease in different geographical areas, immunohistochemical staining and in situ hybridisation were used to analyse latent membrane protein 1 (LMP 1) and small nuclear non-transcribed RNAs (EBER-1) respectively. Testing for EBV within the Reed-Sternberg and Hodgkin's cells was carried out in childhood Hodgkin's disease from 10 different countries. The proportion of LMP 1 positive cases varied significantly, being 50% of cases from the United Kingdom (38/75), South Africa (9/18), Egypt (7/14), and Jordan (8/16), 60% from the United Arab Emirates (6/10), 70% from Australia (11/16), 81% from Costa Rica (34/42), 88% from Iran (7/8), 90% from Greece (20/22), and 100% of the 56 cases from Kenya. A sensitive polymerase chain reaction based EBV strain typing technique was established using archival tissues. EBV strain type 1 was shown to be predominant in childhood Hodgkin's disease from the United Kingdom, South Africa, Australia, and Greece. Type 2 was predominant in Egypt. EBV strain types 1 and 2 were both detected in some cases of childhood Hodgkin's disease in the United Kingdom, Costa Rica, and Kenya. The high incidence of EBV and the presence especially in developing countries of dual infection with both strain types 1 and 2 may reflect socioeconomic conditions leading to malnutrition induced immunological impairment. The possibility of HIV infection also needs to be explored.  相似文献   
102.
Scientific information on the potential harmful effects of silver nanoparticles (AgNPs) on human health severely lags behind their exponentially growing applications in consumer products. In assessing the toxic risk of AgNP usage, liver, as a detoxifying organ, is particularly important. The aim of this study was to explore the toxicity mechanisms of nano and ionic forms of silver on human hepatoblastoma (HepG2) cells. The results showed that silver ions and citrate‐coated AgNPs reduced cell viability in a dose‐dependent manner. The IC50 values of silver ions and citrate‐coated AgNPs were 0.5 and 50 mg L?1, respectively. The LDH leakage and inhibition of albumin synthesis, along with decreased ALT activity, indicated that treatment with either AgNP or Ag ions resulted in membrane damage and reduced the cell function of human liver cells. Evaluation of oxidative stress markers demonstrating depletion of GSH, increased ROS production, and increased SOD activity, indicated that oxidative stress might contribute to the toxicity effects of nano and ionic forms of silver. The observed toxic effect of AgNP on HepG2 cells was substantially weaker than that caused by ionic silver, while the uptake of nano and ionic forms of silver by HepG2 cells was nearly the same. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 679–692, 2016.  相似文献   
103.
BACKGROUND: Transforming growth factor-beta (TGF-beta) has been identified as an important component of wound healing. Recent developments in molecular therapy offer exciting prospects for the modulation of wound healing, specifically those targeting TGF-beta. The purpose of this study was to analyze the effect of TGF-beta targeting on the expression of matrix metalloproteinases (MMPs) in fibroblasts isolated from radiation-induced chronic dermal wounds. MATERIALS AND METHODS: The expression of MMPs in tissue samples from radiation-induced chronic dermal wounds was investigated by immunohistochemistry and microarray technique. The effect of TGF-beta targeting using antisense oligonucleotides on the expression of MMPs in isolated fibroblasts was analysed by ELISA and multiplex RT-PCR. RESULTS: Immunohistochemical investigation and microarray analysis demonstrated an increased expression of MMP protein and mRNA in tissue samples from radiation-induced chronic dermal wounds compared to normal human skin. Antisense TGF-beta oligonucleotide treatment significantly down-regulated MMP secretion in vitro. CONCLUSION: TGF-beta antisense oligonucleotide technology may be a potential therapeutic option for the inhibition of proteolytic tissue destruction in radiation-induced chronic wounds.  相似文献   
104.
Aerobic endurance exercise (AEX) is an effective treatment in the prevention and management of high blood pressure (BP). Growing evidence suggests potential benefits from isometric handgrip (IHG) exercise, which may promote similar or even larger reductions in BP than AEX. We compared the effects of home-based AEX and home-based IHG on BP. Sixty healthy individuals (31 men; mean age, 33.1 years; mean BP, 126.9 ± 1.6/84.7 ± 1.1 mm Hg) were randomized to IHG, AEX, or a control group. Both exercise interventions were performed in the home environment. The IHG group performed daily 4 × 2 minutes sustained grips at 30% of maximal volitional contraction. Participants in the AEX group were advised to perform at least 150 min/wk of aerobic exercise at moderate intensity. Outcome measurements were assessed at baseline and 8 weeks of follow-up. Compared with the control group, AEX resulted in a larger reduction in ambulatory BP; both AEX and IHG exercise tended to induce larger reductions in office systolic BP, and office diastolic BP was significantly more reduced after AEX but not IHG exercise. Responses to training were not significantly different between both the exercise interventions. Eight weeks of home-based AEX results in significant reductions in both ambulatory BP and office BP in healthy adults, whereas IHG reduces only office BP.  相似文献   
105.
CONCLUSION: The palatal implant method originally designed to reduce snoring can significantly reduce the apnea-hypopnea index (AHI) in some patients with mild to moderate obstructive sleep apnea (OSA) in a single office-based procedure. OBJECTIVE: An initial study designed to evaluate the short-term efficacy and safety of palatal implants as primary treatment for patients with mild to moderate OSA. MATERIALS AND METHODS: This was a prospective, non-randomized study of 16 previously untreated and undiagnosed patients with sleep apnea. The inclusion criteria were an AHI of 10-30/h and a body mass index (BMI) < or = 30. RESULTS: The mean AHI was reduced following implantation, from 16.1 to 11.8 (p<0.01). A reduction in AHI was achieved in 13 patients (81%). Ten of 16 patients had their AHI reduced to <10.0. Snoring intensity decreased from 8.3+/-1.8 to 4.7+/-2.5 on a visual analog scale (p<0.001) and daytime sleepiness dropped from 7.2+/-2.5 to 4.6+/-3.2 on the Epworth Sleepiness Scale (p<0.05). No significant adverse events were reported.  相似文献   
106.
Baisch A  Hörmann K  Goessler UR  Sauter A  Riedel F 《HNO》2007,55(5):392-398
Chronic wounds are characterized by slow or nonexistent wound healing. Usually their treatment is expensive. Therefore new concepts in management are of interest in order to reduce treatment time and costs. One option is vacuum sealing. The concept of topical negative pressure is not new, and many chronic nonhealing wounds could be closed successfully with the help of vacuum sealing. Until now, there has been no documented case of vacuum sealing in head and neck reconstructive surgery. Our case shows the effectiveness of a vacuum-assisted device in successful closure of a chronic nonhealing wound in this region.  相似文献   
107.

Background

Contaminated medical products may be vectors for infections. A safe disinfection method for the optical instruments used by ENT specialists is undoubtedly needed. So far, a standard method that sufficiently covers the risk of infection for patients and medical staff alike, while serving the need of practicability in daily routine, has not been established.

Patients and Methods

In the ENT departments of the Mannheim and Kaiserslautern hospitals, a study on the practicability of disinfection rigid optical instruments lacking working channels was conducted using cleaning and disinfection automats. A total of 735 patients were examined (Hopkins 30° and 70°) and the endoscopes subsequently sterilized using a cleaning and disinfection automat.

Results

Each cleaning cycle took about 40 min. Examining 70–100 patients a day, a minimum of eight 70° Hopkins endoscopes would be needed.

Conclusion

The sterilization of medical products such as endoscopes is the best practice, but certain hindrances, such as loss of time and costs involved, complicate its general application.
  相似文献   
108.
Purpose: This study aimed to compare blood pressure (BP) after isolated and combined sessions of aerobic and resistance exercises in hypertensive older women. Heart rate (HR) and heart rate variability (HRV) were included as additional variables. Methods: Twenty-one older women (63±1.9 years; 69.9±2.7 kg; 158.8±2.1 cm) with controlled hypertension (resting BP = 132.2 ± 3.1/74.1 ± 4.0 mmHg) performed four random sessions on different days: 1) aerobic exercise (AE: treadmill walking/running; 40 min; 50–60% HRreserve); 2) resistance exercise (RE: 8 exercises; 3 sets; 15 reps; 40% 1RM)); 3) aerobic exercise followed by resistance exercise (A+R); 4); control (CON). BP, HR and HRV were measured at rest and during 180 min after the sessions. Results: The AE and A+R sessions demonstrated significant decreases in SBP and DBP (30, 60, 120, and 180 min; P < 0.05) and increases in HR (30 and 60 min; P < 0.05) compared to the CON. The RE session demonstrated significant reductions compared to the CON only for DBP (120 and 180 min; P < 0.05). No significant differences were observed in HRV between resting and all sessions. Conclusion: All sessions that involved aerobic exercise (AE and A+R) caused postexercise hypotension in comparison to the CON, with no differences in HRV.  相似文献   
109.

Background

Arsenic exposure in drinking water disproportionately affects small communities in some U.S. regions, including American Indian communities. In U.S. adults with no seafood intake, median total urine arsenic is 3.4 μg/L.

Objective

We evaluated arsenic exposure and excretion patterns using urine samples collected over 10 years in a random sample of American Indians from Arizona, Oklahoma, and North and South Dakota who participated in a cohort study from 1989 to 1999.

Methods

We measured total urine arsenic and arsenic species [inorganic arsenic (arsenite and arsenate), methylarsonate (MA), dimethylarsinate (DMA), and arsenobetaine] concentrations in 60 participants (three urine samples each, for a total of 180 urine samples) using inductively coupled plasma/mass spectrometry (ICPMS) and high-performance liquid chromatography/ICPMS, respectively.

Results

Median (10th, 90th percentiles) urine concentration for the sum of inorganic arsenic, MA, and DMA at baseline was 7.2 (3.1, 16.9) μg/g creatinine; the median was higher in Arizona (12.5 μg/g), intermediate in the Dakotas (9.1 μg/g), and lower in Oklahoma (4.4 μg/g). The mean percentage distribution of arsenic species over the sum of inorganic and methylated species was 10.6% for inorganic arsenic, 18.4% for MA, and 70.9% for DMA. The intraclass correlation coefficient for three repeated arsenic measurements over a 10-year period was 0.80 for the sum of inorganic and methylated species and 0.64, 0.80, and 0.77 for percent inorganic arsenic, percent MA, and percent DMA, respectively.

Conclusions

This study found low to moderate inorganic arsenic exposure and confirmed long-term constancy in arsenic exposure and urine excretion patterns in American Indians from three U.S. regions over a 10-year period. Our findings support the feasibility of analyzing arsenic species in large population-based studies with stored urine samples.  相似文献   
110.
Background/aimThe study aims to evaluate the usage of gold weight implants and monitor complaints and comfort of patients.Materials and methodsA hundred and ninety-one implantations performed between January 2009 and January 2019 were analyzed. Seventy-eight patients included in this study The average age of the patients was 51.3 ± 14.5 years. Forty-five (57.7%) of them were male and 33 (42.3%) female. Patient satisfaction was measured with a questionnaire containing the most common complaints related to gold weight in the literature through telephone surveys.ResultsThe average follow-up time was 74.5 months. Ninety-three-point-five percent of subjects had operational causes, among which the most widespread was acoustic neuroma (44.9%). The average time between facial paralysis and implantation was 141.1 days. Implantation was performed 26.6 days on average after acoustic neuroma surgery and 3.2 days on average after temporal zone malignancy surgery. Thirty-eight patients had their implants removed over either complication (n = 14) or recovery (n = 24). Recovery was the fastest after facial nerve decompression (mean= 4.75 ± 3.6 (2–10) months) and the slowest after 7–12 cranial nerve transfer (mean= 18.3 ± 8.2 (3–31) months). Twenty-six-point-nine percent (n = 21) of patients had complications, of which the most common was extrusion (n = 10). The overall satisfaction rate was 88.5% with the highest in visual acuity and the lowest in continuous requirement for artificial tear. ConclusionThe gold weight implantation is an effective, reversible, and easy procedure significantly reducing complaints regarding paralytic lagophthalmos. Early implementation may be beneficial for ocular complications. A dynamic facial reanimation could terminate need of implant.  相似文献   
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