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241.
The hypothesis of metal defense as a substitute for a defective biotic stress signaling system in metal hyperaccumulators was tested using the pathosystem Alternaria brassicicola–Noccaea caerulescens under low (2 µM), medium (12 µM) and high (102 µM) Zn supply. Regardless the Zn supply, N. caerulescens responded to fungal attack with the activation of both HMA4 coding for a Zn transporter, and biotic stress signaling pathways. Salicylate, jasmonate, abscisic acid and indoleacetic acid concentrations, as well as biotic stress marker genes (PDF1.2, CHIB, LOX2, PR1 and BGL2) were activated 24 h upon inoculation. Based on the activation of defense genes 24 h after the inoculation an incompatible fungal–plant interaction could be predicted. Nonetheless, in the longer term (7 days) no effective protection against A. brassicicola was achieved in plants exposed to low and medium Zn supply. After 1 week the biotic stress markers were even further increased in these plants, and this compatible interaction was apparently not caused by a failure in the signaling of the fungal attack, but due to the lack of specificity in the type of the activated defense mechanisms. Only plants receiving high Zn exhibited an incompatible fungal interaction. High Zn accumulation in these plants, possibly in cooperation with high glucosinolate concentrations, substituted for the ineffective defense system and the interaction turned into incompatible. In a threshold‐type response, these joint effects efficiently hampered fungal spread and, consequently decreased the biotic stress signaling.  相似文献   
242.

Background

Diabetes and hypertension increase arterial stiffness and cardiovascular events in all societies studied so far; sub-Saharan African studies are sparse. We investigated factors affecting arterial function in Ghanaians with diabetes, hypertension, both or neither.

Method

Testing the hypothesis that arterial stiffness would progressively increase from controls to multiply affected patients, 270 participants were stratified into those with diabetes or hypertension only, with both, or without either. Cardio-ankle vascular index (CAVI), heart–ankle pulse wave velocity (haPWV), aortic PWV (PWVao) by Arteriograph, aortic and brachial blood pressures (BP), were measured.

Results

In patients with both diabetes and hypertension compared with either alone, values were higher of CAVI (mean?±?SD, 8.3?±?1.2 vs 7.5?±?1.1 and 7.4?±?1.1 units; p?<?0.05), PWVao (9.1?±?1.4 vs 8.7?±?1.9 and 8.1?±?0.9 m/s; p?<?0.05) and haPWV (8.5?±?1 vs 7.9?±?1 and 7.2?±?0.7 m/s; p?<?0.05) respectively. In multivariate analysis, age, having diabetes or hypertension and BMI were independently associated with CAVI in all participants (β?=?0.49, 0.2, 0.17 and -0.2 units; p?<?0.01, respectively). Independent determinants of PWVao were heart rate, systolic BP and age (β?=?0.42, 0.27 and 0.22; p?<?0.01), and for haPWV were systolic BP, age, BMI, diabetes and hypertension status (β?=?0.46, 0.32, -0.2, 0.2 and 0.11; p?<?0.01).

Conclusion

In this sub-Saharan setting with lesser atherosclerosis than the western world, arterial stiffness is significantly greater in patients with coexistent diabetes and hypertension but did not differ between those with either diabetes or hypertension only. Simple, reproducibly measured PWV/CAVI may offer effective and efficient targets for intervention.
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Amyloid‐like peptides are an ideal model for the mechanistic study of amyloidosis, which may lead to many human diseases, such as Alzheimer disease. This study reports a strong second harmonic generation (SHG) effect of amyloid‐like peptides, having a signal equivalent to or even higher than those of endogenous collagen fibers. Several amyloid‐like peptides (both synthetic and natural) were examined under SHG microscopy and shown they are SHG‐active. These peptides can also be observed inside cells (in vitro). This interesting property can make these amyloid‐like peptides second harmonic probes for bioimaging applications. Furthermore, SHG microscopy can provide a simple and label‐free approach to detect amyloidosis. Lattice corneal dystrophy was chosen as a model disease of amyloidosis. Morphological difference between normal and diseased human corneal biopsy samples can be easily recognized, proving that SHG can be a useful tool for disease diagnosis.  相似文献   
246.

Background and Aim

Asthma and tobacco exposure is common among pregnant women. We investigated the effect of passive and active smoking on asthma control during pregnancy.

Methods

Prospective observational design. Patients had their asthma control, based on symptoms, use of medication, spirometry, and exhaled nitric oxide [FENO], assessed every four weeks during 2nd and 3rd trimester of pregnancy; data on tobacco exposure were also collected prospectively. The primary outcome was episodes of uncontrolled and partly controlled asthma during pregnancy (defined according to GINA-guidelines).

Results

A total of 500 pregnant women with asthma (mean age 30.8 years, range 17 to 44) were consecutively included, of whom 32 (6.4%), 115 (23.0%) and 353 (70.6%), respectively, were current smokers, ex-smokers and never smokers [NS]. Sixty-five NS (18.4%) reported passive tobacco exposure. NS with passive tobacco exposure had significantly lower FEV1% predicted (p<0.02) and FENO (p = 0.01) compared to NS without passive tobacco exposure. The relative risk [RR] of an episode of uncontrolled asthma during pregnancy was 4.5 (95% CI 2.7–7.5: p<0.001) in current and ex-smokers compared with never smokers, and 2.9 (95% CI 1.4–5.9; p = 0.004) in NS-women with passive tobacco exposure compared with NS-women not reporting passive tobacco exposure. Treatment with inhaled corticosteroids, most likely as a marker of more severe asthma, was also associated with a higher risk (RR 8.1, 95% CI 5.1–13.0; p<0.001) of an episode of uncontrolled asthma.

Conclusion

Passive tobacco exposure in never smokers is associated with an increased risk of episodes of uncontrolled asthma during pregnancy, which is likely to have adverse effects on pregnancy outcome.  相似文献   
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This study reports on the C-terminal fragment of the 11S proteasome activator complex (PA28 or Reg alpha), a novel ovarian-specific biomarker of early and late stages of ovarian cancer (OVC) relapse, in patient biopsies after chemotherapy. A total of 179 tissue samples were analyzed: 8 stage I, 55 stage III-IV, 10 relapsed serous carcinomas, 25 mucinous carcinomas and 12 borderline and 68 benign ovarian tissue samples. This fragment was detected by MALDI mass spectrometry profiling in conjunction with a novel extraction method using hexafluoroisopropanol (1,1,1,3,3,3-hexafluoro-2-propanol; HFIP) solvents for protein solubilization and by immunohistochemistry using a specific antibody directed against the C-terminal fragment of PA28. Due to its specific cellular localization, this fragment is a suitable candidate for early OVC diagnosis, patient prognosis and follow-up during therapy and discriminating borderline cancers. Statistical analyses performed for this marker at different OVC stages reflect a prevalence of 77.66 ± 8.77 % (with a correlation coefficient value p < 0.001 of 0.601 between OVC and benign tissue). This marker presents a prevalence of 88 % in the case of tumor relapse and is detected at 80.5 % in stage I and 81.25 % ± 1.06 in stage III-IV of OVC. The correlation value for the different OVC stages is p < 0.001 of 0.998. Taken together, this report constitutes the first evidence of a novel OVC-specific marker.  相似文献   
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