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41.
To elucidate the early events of blood-borne metastasis under actual blood flow, real-time trafficking of RAW117 large cell lymphoma cells, namely parental RAW117-P and liver-metastatic RAW117-H10 cells, was investigated using positron emission tomography (PET). Both types of cells accumulated in the liver immediately after injection via the portal vein, and were eliminated from the liver time-dependently. The elimination rate of RAW117-H10 cells, however, was slower than that of RAW117-P cells, suggesting that RAW117-H10 cells interact more strongly with hepatic sinusoidal endothelium than the parental cells. This result correlated with the metastatic potential of these cells: RAW117-H10 cells metastasized in the liver to a greater extent than RAW117-P cells after injection via this route. To investigate the role of sialylglycoconjugates in the interaction of RAW117-H10 cells with the hepatic endothelium after injection via the portal vein, the trafficking of RAW117-H10 cells was examined after the cells had been treated with sialidase. The elimination rate of RAW117-H10 cells from liver was observed to be greatly accelerated by sialidase treatment. To elucidate what kind of sialylglycoconjugates is related to this phenomenon, we analyzed the distribution of sialyl Lewis A and sialyl Lewis X antigens of both sublines of RAW117 by using flow cytometry. RAW117-H10 cells were found to express a much higher level of sialyl Lewis A than RAW117-P cells, whereas the amount of sialyl Lewis X did not differ significantly. These findings suggest that some sialylglycoconjugates, perhaps sialyl Lewis A in particular, play an important role in the initial interaction of RAW117-H10 cells with the hepatic endothelium, leading to metastasis.  相似文献   
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43.
An 82-year-old female was referred to our hospital because a 16 x 8 cm tumor detected in her liver by abdominal ultrasonography (echo, hereafter) and CT. The patient was diagnosed as having highly advanced cholangiocellular carcinoma (CCC) by abdominal angiography. Since excision of the tumor was impossible due to the patient's age, a reservoir was indwelled for intra-arterial injection into the liver. Continuous injection of 1,000 mg 5-FU over 24 hours was performed every 2 weeks using a portable disposable pump 70 times. The tumor has been markedly reduced since the start of chemotherapy, with a reduction rate (PR) of 98% over the 3 years until the present. Since the frequency of administration was low, only twice a month, the patient had few side effects despite her old age, and injections could be performed in the outpatient department. Usually, the prognosis for CCC is poor. However, the patient has maintained a good QOL with the periodic intra-arterial injection of the carcinostatic into the liver, and this treatment has had a strong antitumor effect. This chemotherapy is thus considered useful for CCC which can not be resected.  相似文献   
44.
T cell lymphoma carrying Epstein Barr virus (EBV(+) TL) is very rare among Western countries while it is much more common among Japanese. Here we report an EBV(+) TL which has been maintained for years by the use of mice with severe combined immune deficiency (SCID) mice. Lymphoma was obtained from a 55-year-old male suffering from oculomotor nerve palsy and lymphadenopathy. A small piece of biopsied tumor was transplanted into SCID mice and the lymphoma has been maintained for over 3 years with passages every 2 - 3 weeks. The maintained lymphoma, termed as TMS24, and the original lymphoma cells showed identical phenotype and genotype, including diffuse medium-sized cell morphology lacking granules, suppressor / cytotoxic immunophenotype and identical T cell receptor beta-chain gene rearrangement mode. Further, both were shown to carry an identical EBV clone in terms of the number of terminal repeats and the latency II-type restricted gene expression profile. Cytogenetically, TMS24 retained two characteristic chromosomal translocations of t(1;18)(q32;q21) and t(6;12)(p21;q24). Since only one cell line with such characters has been reported previously, TMS24 should be useful for detailed analysis of EBV(+) TL.  相似文献   
45.
46.
Gamma-aminobutyric acid (GABA) is present in the mammalian brain as the main inhibitory neurotransmitter and in foods. It is widely used as a supplement that regulates brain function through stress-reducing and sleep-enhancing effects. However, its underlying mechanisms remain poorly understood, as it is reportedly unable to cross the blood–brain barrier. Here, we explored whether a single peroral administration of GABA affects feeding behavior as an evaluation of brain function and the involvement of vagal afferent nerves. Peroral GABA at 20 and 200 mg/kg immediately before refeeding suppressed short-term food intake without aversive behaviors in mice. However, GABA administration 30 min before refeeding demonstrated no effects. A rise in circulating GABA concentrations by the peroral administration of 200 mg/kg GABA was similar to that by the intraperitoneal injection of 20 mg/kg GABA, which did not alter feeding. The feeding suppression by peroral GABA was blunted by the denervation of vagal afferents. Unexpectedly, peroral GABA alone did not alter vagal afferent activities histologically. The coadministration of a liquid diet and GABA potentiated the postprandial activation of vagal afferents, thereby enhancing postprandial satiation. In conclusion, dietary GABA activates vagal afferents in collaboration with meals or meal-evoked factors and regulates brain function including feeding behavior.  相似文献   
47.
The aim of this study was to investigate the influence of systemic chemotherapy on the skeletal growth of young osteosarcoma patients as a treatment-related late adverse effect. We reviewed the height data of 20 osteosarcoma patients (13 males and 7 females) aged ≤18 years. The average (±SD) age at diagnosis was 14.5 (±3.3) years. The average follow-up interval was 89.6 months. After wide resection of the affected bones, reconstruction with tumor prostheses and auto-bone grafting was carried out in 11 and 9 cases, respectively. Pearson’s correlation coefficient was calculated to evaluate the association between actual and predicted (using Paley’s multiplier method) heights. Z-scores were used to compare the initial and final heights with the Japanese national growth curve. Actual and predicted heights were correlated according to Pearson’s correlation coefficient (R = 0.503). Z-analysis showed that statistical significance (p = 0.04) was noted for the height data Z-scores of patients between ≤10 years and >10 years at the final follow-up. Systemic chemotherapy did not reduce skeletal growth in young osteosarcoma patients as a late adverse effect based on two different evaluation methods. However, patients aged ≤10 years at diagnosis may develop a short stature after systemic chemotherapy.  相似文献   
48.

Background

In Japan, the cervical cancer screening rate is extremely low. Towards improving the cervical cancer screening rate, encouraging eligible people to make an informed choice, which is a decision-making process that relies on beliefs informed by adequate information about the possible benefits and risks of screening, has attracted increased attention in the public health domain. However, there is concern that providing information on possible risks of screening might prevent deter from participating.

Methods

In total, 1,912 women aged 20–39 years who had not participated in screening in the fiscal year were selected from a Japanese urban community setting. Participants were randomly divided into 3 groups. Group A received a printed reminder with information about the possible benefits of screening, group B received a printed reminder with information about possible benefits and risks, and group C received a printed reminder with simple information only (control group).

Results

Out of 1,912 participants, 169 (8.8%) participated in cervical cancer screening. In the intervention groups, 137 (10.9%) participated in cervical cancer screening, compared to only 32 (4.9%) of the control group (p < 0.001). In addition, logistic regression analysis revealed that there was no significant difference in screening rate between group A and group B (p = 0.372).

Conclusions

Providing information on the possible risks of screening may not prevent people from taking part in cervical cancer screening among a Japanese non-adherent population.  相似文献   
49.
A man in his 30s injected insulin several times into his abdomen and was found dead several hours later. Micropathological findings showed alveolar injury with hemorrhaging and cerebral parietal lobe nerve cell edema. Biochemical examinations showed that the blood insulin level was high, significantly so at the insulin injection sites. The blood glucose and C-peptide levels were low. The insulin level in the kidneys was low. In forensic medicine, a postmortem diagnosis of insulin subcutaneous injection is often difficult. When insulin injection is suspected, particularly high insulin levels can be expected at the insulin injection site, rather than in the blood.  相似文献   
50.
Colloidal crystals (CCs) are periodic arrays of monodisperse microparticles. Such CCs are very attractive as they can be potentially applicable as versatile photonic devices such as reflective displays, sensors, lasers, and so forth. In this article, we describe a promising methodology for synthesizing monodisperse magnetite microparticles whose diameters are controllable in the range of 100–200 nm only by adjusting the base concentration of the reaction solution. Moreover, monodisperse magnetite microparticles in aqueous suspensions spontaneously form the CC structures under an external magnetic field, leading to the appearance of Bragg reflection colors. The reflection peak can be blue-shifted from 730 nm to 570 nm by the increase in the external magnetic field from 28 mT to 220 mT. Moreover, the reflection properties of CCs in suspension depend on the microparticle concentration in suspension and the diameter of the magnetite microparticles. Both fine-control of microparticle diameter and investigation of magneto-optical properties of CCs would contribute to the technological developments in full-color reflective displays and sensors by utilizing these monodisperse magnetite microparticles.  相似文献   
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