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The purpose of this study was to determine whether the transport of small hydrophilic molecules across the blood-brain barrier (BBB) during focal cerebral ischemia could be altered by a topical application of endothelin-1 (ET-1) in the ischemic cortex (IC). Forty minutes after middle cerebral artery (MCA) occlusion, patches of 10 nM ET-1 (low-endothelin group), 100 nM ET-1 (high-endothelin group), or normal saline (control group) were placed on the IC of rats for a 20-min period. One hour after MCA occlusion, transfer coefficient (Ki) of [14C-alpha-]aminoisobutyric acid (14C-AIB) or regional cerebral blood flow (rCBF) was determined. Vital signs were not significantly different among the experimental groups. In the control group (n=8), the Ki of the IC was significantly higher than that of the contralateral cortex (CC; 11.9+/-5.8 vs 5.0+/-1.9 microl/g per minute). In the low-endothelin group (n=8), the Ki of the IC was still significantly higher than that of the CC (9.4+/-5.2 vs 5.3+/-2.5 microl/g per minute). However, in the High-endothelin group (n=8), the Ki of the IC was not different from that of the CC (6.9+/-2.1 vs 5.6+/-2.3 microl/g per minute) and 42% lower than that of the control group. The rCBF was not affected by 100 nM of ET-1 [control (n=6): IC 53+/-18 ml/100 g per minute, CC 94+/-23 ml/100 g per minute; high-endothelin (n=6): IC 49+/-15 ml/100 g per minute, CC 98+/-24 ml/100 g per minute]. Our data suggest that the application of endothelin-1 in the IC could reduce the transfer coefficient of small hydrophilic molecules across the BBB during focal ischemia.  相似文献   
575.
The incidence of wound infections that do not adequately respond to standard-of-care antimicrobial treatment has been increasing. To address this challenge, a novel antimicrobial magnetic thermotherapy platform has been developed in which a high-amplitude, high-frequency, alternating magnetic field is used to rapidly heat magnetic nanoparticles that are bound to Staphylococcus aureus (S. aureus). The antimicrobial efficacy of this platform was evaluated in the treatment of both an in vitro culture model of S. aureus biofilm and a mouse model of cutaneous S. aureus infection. We demonstrated that an antibody-targeted magnetic nanoparticle bound to S. aureus was effective at thermally inactivating S. aureus and achieving accelerated wound healing without causing tissue injury.  相似文献   
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Wu-Ling-San (WLS) formula has been proved to prevent calcium oxalate nephrolithiasis both in vitro and in vivo. This is the first prospective, randomized and placebo-controlled clinical trial of WLS in calcium oxalate nephrolithiasis prevention. All patients who enrolled were asked to drink enough fluid to urinate at least 2 L daily during the study period. A 24-hour urine collection was performed to establish the baseline levels of multiple urinary parameters before taking the medicine. The patients were randomized and divided into two groups. The medication group took 2 gm WLS formula three times daily for 1 month. The control group took 2 gm placebo three times daily for 1 month. A 24-hour urine collection was performed to evaluate multiple urinary and serum parameters from all patients during the study period. A total of 39 patients were enrolled and 28 patients completed the study. Fourteen patients were allocated to WLS group and 14 patients to placebo group. After treatment, the mean urine output level increased to 2796.4 ± 525.7 ml/day (percentage of change, 13.9 %) in the WLS formula group. With placebo therapy, the mean decreased slightly to 2521.4 ± 762.7ml/day (percentage of change, −5.7 %). The percentage of change was significantly different between the two groups (independent t-test, P=0.02). No patient complained of side effects, such as fatigue, dizziness, musculoskeletal symptoms, or gastrointestinal disturbance. WLS formula is a promising adjunct to surgical and medical management of kidney stones. Active therapy with WLS formula has a positive effect on diuresis without leading to electrolyte imbalance.  相似文献   
577.

Objective

This study examined the prevalence and correlates of depressive symptoms in North Korean defectors who have been living in South Korea for more than one year.

Methods

We used questionnaires developed by the authors to collect sociodemographic data in addition to the Center for Epidemiologic Studies Depression Scale (CES-D), the Psychosocial Well-being Index to measure stress, and a social support scale. A total of 367 subjects were included in this study.

Results

The results showed that 30.5% of the men and 34.7% of the women reported depressive symptoms, and 33.1% of the men and 36.1% of the women exhibited signs of severe distress. Correlates of depressive symptoms were lack of occupation [odds ratio (OR)=2.198, 95% confidence interval (CI), 1.247-3.873], having escaped without family (OR=1.725, 95% CI, 1.006-2.959), and a poor subjective sense of health status (OR=3.111, 95% CI, 1.591-6.085).

Conclusion

Continuing vocational training and career management, psychological support programs, and intensive physical health services are needed to improve the mental health of this population.  相似文献   
578.
BACKGROUND/AIMS: Antibiotic resistance of Helicobacter pylori (H. pylori) is a significant clinical problem because it reduces the efficacy of eradication therapy. The aims of this study were to assess the changing patterns of antibiotic resistance of H. pylori in patients with peptic ulcer diseases and to evaluate the eradication rate in antibiotic resistant H. pylori strains. METHODS: One hundred forty four H. pylori isolates obtained from 466 patients with peptic ulcer disease between June 2001 and December 2005 were examined for antimicrobial resistance. The minimum inhibitory concentration (MIC) of metronidazole was determined by modified broth microdilution method (mBMD) and E test. MICs of clarithromycin and amoxicillin were determined by mBMD, E test, and disc diffusion test. The breakpoints for metronidazole, clarithromycin, and amoxicillin resistance were defined as >8 microg/mL, >1 microg/mL, and > or =1 microg/mL, respectively. RESULTS: Resistance to metronidazole and clarithromycin was detected in 34.7% and 16.7% of H. pylori isolates, respectively. During the recent 5-year study period, amoxicillin-resistant rate of H. pylori was 11.8%, and multi-drug resistance rate of H. pylori was 16.7%. The eradication rate of clarithromycin containing triple therapies was low (7.8%) in clarithromycin-resistant H. pylori strains. CONCLUSIONS: The proportions of clarithromycin-resistant H. pylori strains have increased significantly over the last 5-years. There is an increasing tendency for the emergence of strains with multi-drug resistance. The increase in clarithromycin-resistant strains results in a decrease in eradication rate for H. pylori. In areas with high clarithromycin resistance, new alternative first-line treatment combination should be considered.  相似文献   
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BackgroundTraumatic events are thought to be a cause of acral melanoma. However, little is known about the role of mechanical trauma or physical stress in the development of acral melanoma.ObjectiveIn our study, we evaluated the frequency of trauma, physical stress, and occupation in patients with acral melanoma and aimed to identify any pathological correlates of these factors.MethodsWe conducted a retrospective study of 313 acral melanoma patients from Chonnam National University Hospital. We mapped melanoma-developed anatomical sites of acral areas and assessed patients'' history of trauma, physical stress, and occupation.ResultsAmong the 313 acral melanoma patients, many reported a traumatic event (84 of 313; 26.8%) or physical stress (91 of 313; 29.1%) before the melanoma developed. The most common anatomical sites in these patients were on the borders of the foot (136 of 313; 43.5%). Trauma was more commonly associated with the fingernails and toenails than other sites. The frequency of each type of physical stress depended on the site of the lesion. Farmer and fisherman were the most common occupations (130 of 313; 41.5%) of the acral melanoma patients.ConclusionOur results demonstrate that traumatic events, physical stress, and certain occupations are common in acral melanomas. Further studies are needed to establish whether these are risk factors for acral melanomas.  相似文献   
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