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991.
Summary The response of the cell to DNA damage and its ability to maintain genomic stability by DNA repair are crucial in preventing cancer initiation and progression. Therefore, polymorphism of DNA repair genes may affect the process of carcinogenesis. The importance of genetic variability of the components of mismatch repair (MMR) genes is well documented in colorectal cancer, but little is known about its role in breast cancer. hMSH2 is one of the crucial proteins of MMR. We performed a case-control study to test the association between two polymorphisms in the hMSH2 gene: an A → G transition at 127 position producing an Asn → Ser substitution at codon 127 (the Asn127Ser polymorphism) and a G → A transition at 1032 position resulting in a Gly → Asp change at codon 322 (the Gly322Asp polymorphism) and breast cancer risk and cancer progression. Genotypes were determined in DNA from peripheral blood lymphocytes of 150 breast cancer patients and 150 age-matched women (controls) by restriction fragment length polymorphism and allele-specific PCR. We did not observe any correlation between studied polymorphisms and breast cancer progression evaluated by node-metastasis, tumor size and Bloom-Richardson grading. A strong association between breast cancer occurrence and the Gly/Gly phenotype of the Gly322Asp polymorphism (odds ratio 8.39; 95% confidence interval 1.44–48.8) was found. Therefore, MMR may play a role in the breast carcinogenesis and the Gly322Asp polymorphism of the hMSH2 gene may be considered as a potential marker in breast cancer.  相似文献   
992.
Cerebral aneurysms are the most common reason of subarachnoid haemorrhage at the age of 50-60. Though the results of such haemorrhage are severe (high morbidity and mortality), it is quite often, the first noticeable sign of the problem. Previous symptoms i. e. headache, ophthalmic disturbances, temporary neurological symptoms are often passed over. The authors present the case of a young woman with cerebral aneurysms, in which the visual acuity impairment was the only symptom of the disease.  相似文献   
993.
Prost ME  Semczuk K 《Klinika oczna》2005,107(7-9):418-420
PURPOSE: To evaluate conjunctival bacterial flora in children and its resistance to the most frequently antibiotics used by the ophthalmologists in Poland. MATERIAL AND METHODS: Bacterial conjuntival cultures obtained in 593 children without ocular infections. RESULTS AND CONCLUSIONS: Pathogenic bacterial isolates were identified in 26.3% children. Most frequently isolated were Gram-positive cocci (70.5%). Significant resistance of Gram-positive cocci to aminoglicosides (5% to 65%) was observed. Emerging resistance to fluoroquinolones, especially of coagulase-negative staphylococci (in 21%), was also observed.  相似文献   
994.
Rats pretreated with acetaminophen (N-acetyl-p-aminophenol, APAP) (600 mg/kg b.w., p.o.) were administered with ethanol and ethyl acetate extracts as well as with isocytisoside (100 mg/kg b.w., p.o.) obtained from Aquilegia vulgaris (L.) (Ranunculaceae) herb. The substances tested decreased enzymatic, non-enzymatic and uninduced microsomal lipid peroxidation (LPO) in the liver of rats treated with APAP by 18-48%. Activity of the antioxidant enzymes in the liver inhibited by APAP was increased in the majority of groups after administration of the substances tested: catalase (CAT) by 55%, glutathione peroxidase (GPx) by 50%, glutathione reductase (GR) by 35% and glutathione S-transferase (GST) by 60%. Hepatic glutathione level depleted by APAP was only slightly increased by the substances tested. The cytochrome P450 contents, and the activities of NADPH-cytochrome P450 reductase and two monooxygenases were not affected by the extracts and isocytisoside. It can be concluded that the protective ability of the substances tested in APAP-induced liver injury is mediated by amelioration of microsomal lipid peroxidation and restoring antioxidant enzymes activity. Inhibition of enzymes responsible for metabolic activation of APAP is not involved in this process.  相似文献   
995.
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997.
ABSTRACT: BACKGROUND: In juvenile idiopathic arthritis (JIA), the trend towards early therapeutic intervention and the development of new highly effective treatments have increased the need for sensitive and specific imaging. Numerous studies have demonstrated the important role of MRI and US in adult rheumatology. However, investigations of imaging in JIA are rare, and no previous study has been comparing MRI with Doppler ultrasonography (US) for assessment of arthritis. The aim of the present study was to compare the two imaging methods regarding their usefulness for evaluating disease activity in JIA, and to compare the results with those obtained in healthy controls. METHODS: In 10 JIA patients (median age 14 years, range 11--18), 11 joints (six wrists, three knees, two ankles) with arthritis were assessed by color Doppler US and MRI. The same imaging modalities were used to evaluate eight joints (three wrists, three knees, two ankles) in six healthy age- and sex-matched controls. The US examinations of both the patients and controls were compared with the MRI findings. RESULTS: In 10 JIA patients, US detected synovial hypertrophy in 22 areas of 11 joints, 86% of which had synovial hyperemia, and MRI revealed synovitis in 36 areas of the same 11 joints. Erosions were identified by US in two areas of two joints and by MRI in six areas of four joints. Effusion was shown by US in nine areas of six joints and by MRI in 17 areas of five joints. MRI detected juxta-articular bone marrow edema in 16 areas of eight joints. CONCLUSIONS: The results of this pilot study indicate that both MRI and US provide valuable imaging information on disease activity in JIA. Importantly, the two techniques seem to complement each other and give partly different information. Although MRI is considered to be the reference standard for advanced imaging in adult rheumatology, US seems to provide useful imaging information that could make it an option in daily clinical practice, in JIA as well as in adult rheumatology. However, the current work represents a pilot study, and thus our results need to be confirmed in a larger prospective clinical investigation.  相似文献   
998.
Symptomatic overdrainage of cerebrospinal fluid (CSF) can be seen in shunted hydrocephalus patients and in non-shunted patients with spontaneous intracranial hypotension (SIH). In these patients, intracranial pressure (ICP) monitoring often reveals negative static ICP, while it is less understood how the pulsatile ICP (cardiac induced ICP waves) is affected. This latter aspect is addressed in the present study. A set of 40 ICP recordings from paediatric and adult hydrocephalus patients were randomly selected. Each cardiac induced ICP wave was automatically identified and manually verified by the beginning and ending diastolic minimum pressures and the systolic maximum pressure. The ICP wave parameters (static pressure, amplitude, rise time, rise time coefficient, downward coefficient, wave duration, and area-under-curve) were then automatically computed. The material of 40 ICP recordings provided a total of 3,192,166 cardiac induced ICP waves (1,292,522 in paediatric patients and 1,899,644 in adult patients). No apparent changes in ICP wave parameters were seen when mean ICP became negative, except that the parameters amplitude, rise time coefficient, downward coefficient and area under curve somewhat increased when mean ICP was below -15 mmHg.  相似文献   
999.
Aim of this work was to develop a modular computational model able to interact with ventricular assist devices (VAD) for research and educational applications. The lumped parameter model consists of five functional modules (left and right ventricles, systemic, pulmonary, and coronary circulation) that are easily replaceable if necessary. The possibility of interacting with VADs is achieved via interfaces acting as impedance transformers. This last feature was tested using an electrical VAD model. Tests were aimed at demonstrating the possibilities and verifying the behavior of interfaces when testing VADs connected in different ways to the circulatory system. For these reasons, experiments were performed in a purely numerical mode, simulating a caval occlusion, and with the model interfaced to an external left-VAD (LVAD) in two different ways: with atrioaortic and ventriculoaortic connection. The caval occlusion caused the leftward shift of the LV pv loop, along with the drop in arterial and ventricular pressures. A narrower LV pv loop and cardiac output and aortic pressure rise were the main effects of atrioaortic assistance. A wider LV pv loop and a ventricular average volume drop were the main effects of ventricular-aortic assistance. Results coincided with clinical and experimental data attainable in the literature. The model will be a component of a hydronumerical model designed to be connected to different types of VADs. It will be completed with autonomic features, including the baroreflex and a more detailed coronary circulation model.  相似文献   
1000.
Trichinella larvae were detected in a marten (Martes martes) and a badger (Meles meles) in Poland. The animals were found dead following car accidents. All examined animals derived from the Mazurian Lake district, north-east Poland, near the village Kosewo Górne where Trichinella infection were earlier confirmed in wildlife; red foxes and wild boars. The muscle samples were examined by artificial pepsin-HCl digestion method. The parasites were identified as Trichinella britovi by multiplex polymerase chain reaction method. Larvae were found in two out of three martens and one out of seven examined badgers. This is the first report of the identification of Trichinella britovi larvae from martens and badgers in Poland.  相似文献   
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