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951.
Several viral infections are known to increase the risk of dementia through brain cell damage and systemic infection. The association between hepatitis B and C virus (HBV and HCV) infections and dementia was evaluated using a national sample cohort from South Korea. Using the national cohort study from the Korean National Health Insurance Service, we extracted data for patients with HBV or HCV infection and for matched control participants. The controls were matched to the patients according to age, sex, income, region of residence, and past medical histories. The incidence of HCV infection was higher in the dementia group (1.0% [113/11,228]) than in the control group (0.8% [364/44,912], P = .043). However, there was no difference in the incidence of HBV infection in the dementia and control groups. The adjusted odds ratio (OR) for HCV infection was 1.25 (95% confidence interval [CI] = 1.01–1.54, P = .043) in the dementia group. According to the subgroup analysis by sex, the adjusted ORs for HCV infection were 1.04 (95% CI = 072–1.49, P = .851) in men and 1.38 (95% CI = 1.06–1.79, P = .016) in women. We concluded that the incidence of HCV infection was higher (with a higher OR) in women with dementia than in matched control participants in South Korea.  相似文献   
952.

Purpose

To compare nutrient-stimulated changes in superior mesenteric artery (SMA) blood flow, glucose absorption and glycaemia in individuals older than 65 years with, and without, critical illness.

Methods

Following a 1-h ‘observation’ period (t 0t 60), 0.9 % saline and glucose (1 kcal/ml) were infused directly into the small intestine at 2 ml/min between t 60t 120, and t 120t 180, respectively. SMA blood flow was measured using Doppler ultrasonography at t 60 (fasting), t 90 and t 150 and is presented as raw values and nutrient-stimulated increment from baseline (Δ). Glucose absorption was evaluated using serum 3-O-methylglucose (3-OMG) concentrations during, and for 1 h after, the glucose infusion (i.e. t 120t 180 and t 120t 240). Mean arterial pressure was recorded between t 60t 240. Data are presented as median (25th, 75th percentile).

Results

Eleven mechanically ventilated critically ill patients [age 75 (69, 79) years] and nine healthy volunteers [70 (68, 77) years] were studied. The magnitude of the nutrient-stimulated increase in SMA flow was markedly less in the critically ill when compared with healthy subjects [Δt 150: patients 115 (?138, 367) versus health 836 (618, 1,054) ml/min; P = 0.001]. In patients, glucose absorption was reduced during, and for 1 h after, the glucose infusion when compared with health [AUC120–180: 4.571 (2.591, 6.551) versus 11.307 (8.447, 14.167) mmol/l min; P < 0.001 and AUC120–240: 26.5 (17.7, 35.3) versus 40.6 (31.7, 49.4) mmol/l min; P = 0.031]. A close relationship between the nutrient-stimulated increment in SMA flow and glucose absorption was evident (3-OMG AUC120–180 and ?SMA flow at t 150: r 2 = 0.29; P < 0.05).

Conclusions

In critically ill patients aged >65 years, stimulation of SMA flow by small intestinal glucose infusion may be attenuated, which could account for the reduction in glucose absorption.  相似文献   
953.
The present work examines the potential of sesquiterpenoids to sensitize Escherichia coli and Staphylococcus aureus, and modulate their susceptibility to the standard antibiotics ciprofloxacin, erythromycin, gentamicin and vancomycin. It was tested samples of three sesquiterpenoids: guaiazulene, nerolidol (racemic mixture of the cis and trans isomers) and germacrene D enriched natural extract. Experiments were conducted aiming to assess the antimicrobial effects of the antibiotic-sesquiterpenoid combination on bacterial growth inhibition, by the disc diffusion assay and the minimum inhibitory concentration (MIC) assessment, the bactericidal effects, the post-antibiotic effect (PAE) and the effect on membrane permeability. The data related with the antimicrobial activity evidenced, through the disc diffusion assay, an antibiotic S. aureus antimicrobial activity enhancement by sesquiterpenoids presence. The MIC value for E. coli decreased significantly by sesquiterpenoids combination with ciprofloxacin, erythromycin and gentamicin, and for S. aureus, with all four selected antibiotics. This combination also increased the PAE, with the exception of guaiazulene, which seemed to quench antibiotic antimicrobial action. A moderate correlation between antimicrobial action and impairment of cell membrane function was detected for germacrene D enriched extract, and nerolidol, as single treatments and in combination with antibiotic, while a poor correlation was obtained for guaiazulene. This study provides basis for the evaluation of sesquiterpenoids as alternative or possible synergistic compounds for current antimicrobial chemotherapeutics, showing the practical utility of natural derived products to increase the susceptibility of E. coli and S. aureus.  相似文献   
954.
INTRODUCTION: It is known that mechanical ventilation and many of its features may affect the evolution of inspiratory muscle strength during ventilation. However, this evolution has not been described, nor have its predictors been studied. In addition, a probable parallel between inspiratory and limb muscle strength evolution has not been investigated. OBJECTIVE: To describe the variation over time of maximal inspiratory pressure during mechanical ventilation and its predictors. We also studied the possible relationship between the evolution of maximal inspiratory pressure and limb muscle strength. METHODS: A prospective observational study was performed in consecutive patients submitted to mechanical ventilation for > 72 hours. The maximal inspiratory pressure trend was evaluated by the linear regression of the daily maximal inspiratory pressure and a logistic regression analysis was used to look for independent maximal inspiratory pressure trend predictors. Limb muscle strength was evaluated using the Medical Research Council score. RESULTS: One hundred and sixteen patients were studied, forty-four of whom (37.9%) presented a decrease in maximal inspiratory pressure over time. The members of the group in which maximal inspiratory pressure decreased underwent deeper sedation, spent less time in pressure support ventilation and were extubated less frequently. The only independent predictor of the maximal inspiratory pressure trend was the level of sedation (OR=1.55, 95% CI 1.003 - 2.408; p = 0.049). There was no relationship between the maximal inspiratory pressure trend and limb muscle strength. CONCLUSIONS: Around forty percent of the mechanically ventilated patients had a decreased maximal inspiratory pressure during mechanical ventilation, which was independently associated with deeper levels of sedation. There was no relationship between the evolution of maximal inspiratory pressure and the muscular strength of the limb.  相似文献   
955.
OBJECTIVE: To evaluate the effects of estrogen treatment in combination with gestrinone on an experimental rat model of endometriosis. METHODS: Uterine transplants were attached to the peritoneum of female Wistar rats via a surgical autotransplantation technique. The implanted area was measured during the proestrus phase and after hormonal treatment. We performed morphometric analysis and examined the macroscopic and morphometric alterations of endometrial implants after hormonal treatment in ovariectomized rats. RESULTS: The high dose of estrogen caused macroscopic increases in the endometrial implant group compared with other groups, which were similar to increases in the proestrus phase. The low dose showed morphometric development of implants, such as an increase in number of endometrial glands, leukocyte infiltration and mitosis. Gestrinone antagonized both doses of estrogen. CONCLUSION: Our findings suggest that gestrinone antagonizes estrogen's effects on rat peritoneal endometrial implants.  相似文献   
956.
The present study investigated the effects of 8 week of resistance training (RT) on hemodynamic and ventricular function on cardiac myosin ATPase activity, and on contractility of papillary muscles of rats. Groups: control (CO), electrically stimulated (ES), trained at 60% (TR 60%) and 75% of one repetition maximum (1RM) (TR 75%). Exercise protocol: 5 sets of 12 repetitions at 60 and 75% of 1RM, 5 times per week. The CO and ES groups had similar values for parameters analyzed (P > 0.05). Blood pressure (BP), heart rate (13%), left ventricle systolic pressure (LVSP 13%) decreased and cardiac myosin ATPase activity increased in the TR 75% group (90%, P < 0.05). The contractile performance of papillary muscles increased in trained rats (P < 0.05). Eight weeks of RT was associated with lowering of resting BP, heart rate and LVSP, improvements in contractility of the papillary muscle and an increase of cardiac myosin ATPase activity in rats.  相似文献   
957.
The complement system is a protein cascade capable of neutralizing invading pathogens. One of its activation pathways is the lectin pathway which is dependent on the binding of MBL or the ficolins. The specificity of L-ficolin binding has been investigated previously and it was observed that binding is dependent on acetyl groups. If this was the only requirement this would enable L-ficolin to bind to most mammalian glycosylations since they contain acetylated monosaccharides. To investigate this further L-ficolin was subjected to glycan-array analysis in which L-ficolin binding to 279 different glycans was investigated. Few of these bound L-ficolin above background level but clear structural requirements were discovered.  相似文献   
958.
The relation between the detection of clue cells in cervical smears of women with CIN and the expression of COX-2 in these lesions were determined. Samples from 228 women, treated due to CIN and who underwent cervical conization, were obtained. Hybrid Capture II and Pap smear samples were collected immediately before performing conization. Pathological diagnoses were 11 (5%) normal cervix, 35 (15%) CIN1, 31 (14%) CIN2, and 151 (66%) CIN3. COX-2 immunoreactivity grading on the pathological specimens was based on the German ImmunoReactive score. In cervical smears, 20 fields (40x) were examined, each of them with a minimum count of 10 epithelial cells. When 20% or more of clue cells were detected the sample was considered positive for clue cells. The prevalence of clue cells was similar across histological strata (P = 0.42). Although the expression of COX-2 did not differ in lesions with varying severities (P = 0.24), there was a negative association between the expression of COX-2 and the presence of clue cells in Pap smear (OR = 0.4; 95% CI = 0.2-0.9): only 12% of women with moderate and strong expression of COX-2 had clue cells in their smears, contrasted to 22% of those with negative and weak expression of COX-2. HPV infection was associated in a borderline manner to the expression of COX-2 (P = 0.04; OR = 2.3 95% CI = 1.0-5.4). The reduced expression of COX-2 in CIN specimens may suggest that clue cells interfere with the inflammatory component of the carcinogenic process that lead to CIN.  相似文献   
959.
OBJECTIVE: To analyze histological aspects of ovaries as well as the ovulation of adult mice treated with the anabolic agent hexestrol. METHODS: Thirty adult mice were divided into three groups of 10 animals each: (GI) the animals received a dose of 3 mg/kg of hexestrol; (GII) the animals were given a dose of 6 mg/kg of hexestrol; (GIII) the animals were injected with distilled water (vehicle). Another 10-animal group (GIV) was included, and these mice were injected with propionate testosterone (1.25 mg) after 5 days from the day of birth. Hexestrol was administered intraperitoneally once a day and the treatment lasted 30 days. The mice were then sacrificed; their ovaries and oviducts were removed, submitted to histological routine and analyzed under light microscopy. RESULTS: In mice treated with hexestrol (6 mg/kg) (Group II), ovaries were smaller than those from the controls but highly vascularized; similar results were obtained in GIV. A great number of follicles in several stages of development were found -- however, with no corpora lutea -- in six animals in GII. No corpora lutea were found in GIV. The number of luteal bodies and oocytes in GII was lower than that in GI or GIII. No oocytes were detected in GIV. Finally, the nuclear volume of interstitial cells in GII and GIV was the largest. CONCLUSION: Our data suggest that the anabolic agent hexestrol in a high dose may decrease ovulation in mice.  相似文献   
960.
Homologs to Autographa californica multiple nucleopolyhedrovirus (AcMNPV) open reading frame (ORF) 136 or Acp26 are present within almost all nucleopolyhedroviruses (NPVs). Two copies of the gene are found in some members of group II NPVs, suggesting that it may play an important role in transmission or replication. Phylogenetic analysis revealed that the predicted protein has some similarity with Camelpox virus v-slfn protein, which reduces the virulence of orthopoxviruses in vivo. To investigate the influence of ACP26 on the infectivity and virulence of AcMNPV a bacmid system was used to delete the Acp26 ORF. The Acp26null bacmid was able to generate a transmissible infection in cell culture and larvae, indicating that Acp26 is not essential for propagation of viral infection in vitro or in vivo. Deletion of Acp26 from the AcMNPV genome had no apparent effect on timing or production of infectious BV in cell culture or in insect larvae. Additional comparisons of AcMNPV and Acp26null bacmid viruses showed that deletion of Acp26 did not significantly influence the infectivity and virulence of AcMNPV occlusion bodies or the number produced. The Acp26 may be an auxiliary gene with subtle effects on virus replication and transmission.  相似文献   
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