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421.
A 57-year-old man was admitted to our hospital with cardiomegaly on a chest roentgenogram. A mediastinal tumor was observed during a chest computed tomographic scan and the patient was diagnosed with pericardial synovial sarcoma as a result of a tumor biopsy. Surgery, radiotherapy and chemotherapy were carried out, and although the tumor temporarily decreased in size, it subsequently increased and the patient died approximately 3 years following the initial medical examination. Most synovial sarcomas commonly occur in the vicinity of the joints of the extremities. Therefore, we herein report a rare case of synovial sarcoma which occurred in the pericardium.  相似文献   
422.
Konuma T  Morooka N  Nagasawa H  Nagata S 《Endocrinology》2012,153(7):3111-3122
Adipokinetic hormone (AKH) is a peptide hormone that regulates the nutritional state in insects by supporting the mobilization of lipids. In the present study, we manipulated AKH signaling to evaluate how metabolic state regulates feeding in an orthopteran insect, the two-spotted cricket, Gryllus bimaculatus. This was accomplished by RNA interference (RNAi) targeting the receptor gene for AKH [G. bimaculatus AKHR (GrybiAKHR)]. We found that the knockdown of GrybiAKHR by AKHR-double-stranded RNA treatment decreased the levels of 1,2-diacylglycerol and trehalose in the hemolymph, whereas it increased the level of triacylglycerol in the fat body. In addition, the knockdown of GrybiAKHR enhanced starvation resistance and increased food intake. Furthermore, direct observation of GrybiAKHR(RNAi) crickets revealed that the knockdown of GrybiAKHR increased feeding frequency but did not alter meal duration, whereas locomotor activity decreased. The increased frequency of feeding by GrybiAKHR(RNAi) crickets eventually resulted in an increase of food intake. These data demonstrate that the regulation of the metabolic state by AKH signaling affects feeding frequency, probably through nutritional control.  相似文献   
423.

Objectives

To investigate fluorodeoxyglucose (FDG) accumulation in large joints, bursas, and large vessels in patients with polymyalgia rheumatica (PMR) using 18-FDG positron emission tomography/computed tomography (PET/CT) and to differentiate PMR from similar diseases.

Methods

Fourteen untreated patients with active PMR and 17 control patients with rheumatoid arthritis (n?=?11) or other active rheumatic diseases (n?=?6) underwent 18-FDG PET/CT. FDG uptake in large joints, bursas and vertebral spinous processes was evaluated by calculating maximum standardised uptake values and by visual scoring (scale 0–4). PET scan images were scored in seven vascular regions, and total vascular scores (range 0–21) were calculated.

Results

Polymyalgia rheumatica patients showed increased FDG uptake in ischial tuberosities, greater trochanters, and lumbar spinous processes. Positive results at two or more of these sites showed high sensitivity (85.7%) and specificity (88.2%) for the diagnosis of PMR, and shoulder or hip-joint involvement showed low disease specificity. High FDG accumulations were found in the aortas and subclavian arteries of two PMR patients who were asymptomatic for temporal arteritis and scanty synovium and perisynovium, based on FDG uptake. PET/CT images of the 12 PMR patients without apparent vascular involvement showed synovitis and/or perisynovitis.

Conclusions

Fluorodeoxyglucose-PET/CT may be useful for the detection of PMR lesions, which are difficult to identify using other methods.  相似文献   
424.
Background: A few studies have explored the prevalence of dyslexia among children who speak Japanese as their native language by evaluating them individually by means of reading‐based tasks. The present study was designed to clarify the frequency of suspected dyslexia among second‐graders attending ordinary classes. Methods: The subjects were 40 children (22 males, 18 females; 7 years 4 months–8 years 4 months; mean age, 7 years 11 months) out of 182 second‐graders at a public elementary school situated in a local city. Each subject underwent a monomoraic syllable reading task, a word reading task, a non‐word reading task, and a short sentence reading task. Results: The scores on the four tests were not normally distributed; rather, they were strongly skewed to shorter reading time or fewer reading errors. In addition, they were significantly extended toward either longer reading time or more reading errors. Except in the non‐word reading task, most subjects only made a few reading errors. Seven subjects (17.5%) showed at least one score that was more than 1.5 IQR (interquartile range) higher than the third quartile of that subject's eight scores on the four tasks. Assuming that those seven children are potentially dyslexic, at least 3.8% of second‐graders (seven out of 182) are suspected to be suffering from dyslexia. Conclusion: It is likely that the prevalence of dyslexia in Japan is comparable to that in Europe and the US. To confirm this, a more comprehensive study on a larger scale should be implemented in the future.  相似文献   
425.

Background

Recent studies have revealed that the low-affinity nerve growth factor receptor, p75 neurotrophin receptor (p75NTR), is important in inflammatory pain. Moreover, p75NTR immunoreactive sensory nerve and dorsal root ganglion (DRG) neurons have been found to innervate lumbar intervertebral discs. The purpose of the current study was to investigate the effect of p75NTR saporin, a toxin used to destroy p75NTR, on calcitonin gene-related peptide (CGRP), an inflammatory neuropeptide associated with pain, in DRG neurons innervating punctured intervertebral discs in rats.

Methods

The neurotracer fluorogold (FG) was applied to the surfaces of L5/6 discs to label their innervating DRG neurons (n = 30). Of 30 rats, 10 were in a nonpunctured disc sham surgery control group (nonpuncture group), and the other 20 were in experimental groups in which intervertebral discs were punctured with a 23-gauge needle. p75NTR saporin was applied to the discs of 10 rats (puncture + p75NTR saporin group) and the other 10 received the same volume of saline (puncture + saline group). At 14 days after surgery, DRGs from L1 to L6 were harvested, sectioned, and immunostained for CGRP, and the proportions of CGRP-immunoreactive DRG neurons was evaluated.

Results

Of the FG-labeled neurons innervating the L5/6 disc, the proportion of CGRP-immunoreactive neurons was 32% ± 6% (mean ± SE) in the nonpuncture group, 47.2% ± 8% in the puncture + saline group, and 34.6% ± 9% in the puncture + p75NTR saporin group. The proportion of CGRP-immunoreactive neurons was significantly greater in the puncture + saline group compared with the nonpuncture and puncture + p75NTR saporin groups (P < 0.01).

Conclusions

Half of the DRG neurons innervating the discs were positive for CGRP in the puncture + saline group. CGRP is important for mediating inflammatory and nerve-injured pain and may be important in discogenic pain. However, p75NTR saporin suppressed CGRP expression in DRG neurons. Therefore, p75NTR may be an important receptor for mediating discogenic pain via CGRP expression.  相似文献   
426.
427.
428.
In insects, especially phytophagous insects, feeding behavior occurs at a regular frequency. Although a number of physiological studies have revealed various causal factors leading to feeding behavior in insects, little has been demonstrated regarding the regulatory mechanisms underlying insect feeding behavior. To confirm the presence of an endocrinological regulatory mechanism in feeding behavior, we tested the effects of several biologically active peptides on silkworm, Bombyx mori larvae feeding behaviors. To evaluate the effects of the biologically active peptides, we measured the period of latency to the first bite following sample injection into starved Bombyx larvae. Of the chemically synthesized peptides tested, myosuppressin exhibited a prolonged latency, indicating that myosuppressin is a possible inhibitory peptide in Bombyx larvae. In contrast, injections of tachykinin and short neuropeptide F, which are members of the structurally related RF-amide peptide family, had a shorter latency period, indicating that these two peptides are possible stimulatory peptides. In addition, the present study suggests that this bioassay will be advantageous for screening for peptides that regulate insect feeding behavior.  相似文献   
429.
430.
A 60-year-old man presented with a rare case of primary angiitis of the central nervous system mimicking a tumor-like lesion and manifesting as slight disorientation, left hemiparesis, and motor aphasia. Computed tomography showed multiple low density lesions in the left frontal lobe, brain stem, and right parietal lobe. Magnetic resonance images revealed a slightly enhanced mass lesion in the right parietal lobe with surrounding brain edema. Serum, cerebrospinal fluid, and other image examinations did not show any abnormal findings, so surgical removal of the right parietal mass was performed. Histological examination revealed that the mass consisted of hemorrhagic infarction without cellular atypia. Proliferations of endothelial cells in small and medium arteries, and infiltration of macrophages in the perivascular space were detected in the infarction tissues. The histological diagnosis was primary angiitis of the central nervous system.  相似文献   
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