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The human mallei, incudes and stapedes from 34 cadavers were examined using scanning electron microscope (SEM) to compare the bone surface type among different regions of auditory ossicles for males and females. On the malleus of both males and females, almost all of the surfaces showed a smooth fibrous appearance, characteristic of resting surface. Limited bone-forming or resorbing surfaces were identified on the malleus. As compared with the malleus, the percentage area of the resorbing surface and the vascular canal openings were higher on the incus and stapes, especially on the long process (Crus longum) of the incus and the neck of the stapes for both males and females. The percentage area occupied by the resorbing surface of the long process of the incus and the neck of the stapes correlated with that of the vascular canal openings. We consider that the malleus maintained the stable condition, while the long process of the incus and the neck of the stapes demonstrated marked bone resorption. We suppose that the bone erosion may be related to the vascularization in these regions. Though the percentage area of the resorbing surface and the vascular canal openings had the tendency to be high in females, we did not find any significant differences between the males and females. There was no significant correlation between the age and the area of resorbing surface or vascular canal openings.  相似文献   
3.
The origin and characteristics of so-called stromal cells (stromal cell) and the osteoclast-like giant cell series of 19 cases of giant cell tumor (G.C.T.) of bone were studied. Immunohistochemically, two interesting cases were found. The stromal cells of one case were alpha-1-antitrypsin positive and those of the other case were alpha-1-antichymotrypsin positive. The histiocytic stromal cells of the latter case seemed to be surely neoplastic since they showed mild to moderate cell atypism. There were foci consisting of fibroblastic cells or osteoid and osteoblasts within the tumor. Those cells in the foci were apparently continuous with the surrounding stromal cells, and they were, therefore, also considered to be neoplastic. These findings strongly indicate that the stromal cells originate from the undifferentiated mesenchymal cells in the bone marrow and may differentiate to osteoblastic, fibroblastic, and histiocytic cells. All cells of these three series were not stained for a high stable form of acid phosphatase (SAPhase). SAPhase activity was demonstrated only in osteoclast-like giant cells and some mononuclear cells, which are recently believed to be non-neoplastic. Therefore, the cell atypia of SAPhase negative stromal cells is considered to have a prognostic value.  相似文献   
4.
Combining fluorescence R-banding, fluorescence in situ hybridization and spectral karyotyping allowed us to precisely define chromosomal breakpoints, gains, losses and a newly detected amplification in the human mantle cell lymphoma (MCL) cell line GRANTA-519. GRANTA-519 is characterized by the t(11;14)(q13;q32) resulting in overexpression of cyclin D1, a key player in cell cycle control. Hitherto unresolved complex rearrangements involve 1p, 1q, 3cen, 9p, 11q, 12p, 12q, 16p, 17p, and 18cen. Moreover, a 4- to 6-fold gain of sequences on 18q leads to a low-level amplification of the BCL2 gene and to an overexpression of the BCL2 protein. These results provide the basis for the identification of not only candidate oncogenes responsible for MCL in gained regions, but also for the identification of putative tumor suppressor genes in commonly deleted regions like 1p22, which would eventually enable functional studies of these genes.  相似文献   
5.
Early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH)/ataxia with oculomotor apraxia type 1 (AOA1) is caused by mutations in the gene encoding aprataxin (APTX). Although several in vitro findings proposed that impaired enzymatic activities of APTX are responsible for EAOH/AOA1, potential instability of mutant proteins has also been suggested as the pathogenesis based on in vivo finding that mutant proteins are almost undetectable in EAOH/AOA1 tissues or cells. The present study aimed to experimentally prove instability of mutant proteins in neuronal cells, the cell type preferentially affected by this disease. Results of pulse-chase experiments demonstrated that all of the disease-associated mutants had extremely shorter half-lives than the WT. We further found that mutants were targeted for rapid proteasome-mediated degradation. These results help establish pathogenic and physiological protein characteristics of APTX in neuronal cells.  相似文献   
6.
Effects of body position on snoring in apneic and nonapneic snorers   总被引:3,自引:0,他引:3  
Nakano H  Ikeda T  Hayashi M  Ohshima E  Onizuka A 《Sleep》2003,26(2):169-172
STUDY OBJECTIVES: The positional dependency of obstructive sleep apnea (OSA) is well known, but objective evidence for the positional effect on snoring is lacking. The aim of this study is to elucidate the effect of body position on snoring, and that of sleep stage as well. DESIGN: Retrospective analysis of the effects of body position and sleep stage on snoring in nonapneic snorers (snorer group) and OSA patients (apneic group). SETTING: A sleep laboratory in a national hospital in Japan. PATIENTS: Seventy-two patients who complained of habitual snoring and underwent overnight polysomnography. INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: In the lateral position, most subjects in the snorer group showed decreased snoring both in time (p = 0.0004) and intensity (p = 0.0003), but subjects in the apneic group showed variable changes. In the apneic group, the positional dependency of snoring (the ratio of lateral value to supine value) was correlated with supine apnea-hypopnea index (AHI), that is, OSA patients with higher supine AHI tended to show increased snoring in the lateral position. AS to the effect of sleep stage, snoring was increased in deeper non-rapid eye movement sleep and decreased in rapid eye movement sleep in a given position. CONCLUSIONS: This study demonstrated that the positional dependency is different between nonapneic snorers and OSA patients. Most of the nonapneic snorers snore less in the lateral position than in the supine position in contrast to OSA patients who often fail to decrease snoring even in the lateral position.  相似文献   
7.
The authors studied the mode of branching of the celiac trunk in 184 Japanese cadavers during dissecting practice at Gifu University from 1985 to 1988. The findings were as follows; 1) One hundred and sixty-six of the 184 cases belonged to Type I of Adachi's classification of variation in the arrangement of the branches of the celiac trunk. One hundred and twenty-nine cases belonged to Group 1, one case to Group 2, 10 cases to Group 3, 9 cases to Group 4, one case to Group 6, 2 cases to Group 7, 8 cases to Group 8 and 4 cases to Group 11. Two cases did not belong to any group. One of them had an anastomosis between the hepatic artery and the superior mesenteric artery. The other one had the middle colic artery arising from the hepatic artery. 2) Seven cases belonged to Type II, Group 12. 3) Two cases belonged to Type III. One belonged to Group 18. The other one had an accessory right hepatic artery arising from the superior mesenteric artery. 4) One case belonged to Type IV, Group 20. 5) Three cases belonged to Type V, Group 23. 6) Two cases belonged to Type VI. One case had a gastrolienal trunk and an accessory right hepatic artery arising from the superior mesenteric artery. The other one had a gastrolienal trunk and an accessory right hepatic artery arising from the gastrolienal trunk. 7) Of the 184 cases, three could not be classified according to Adachi. Two cases had a gastrolienal trunk and the hepatic artery arising from the abdominal aorta. One case had a lienomesenteric trunk and a gastrohepatic trunk.  相似文献   
8.
The cells from 5 cases of non-lymphocytic leukemia were investigated by immunoelectron microscopy using an anti-granulocyte antibody, clone 1G10 (New England Nuclear), to clarify the nature of immature leukemic cells. Reaction products on the surface of the leukemic cells were composed of two layers, an inner translucent and an outer dense granular zone. Although non-leukemic cells of the granulocytic series in various stages of maturation between promyelocytes and neutrophils were all positive for the antigen-antibody reaction, non-neoplastic monocytes and lymphocytes were all negative. Using this method, it was possible to diagnose the undifferentiated leukemic cells that were negative for myeloperoxidase. Furthermore, the results of our present study suggest the possibility that the antibody 1G10 may be useful for distinguishing granulocytic cells from cells of monocytic lineage.  相似文献   
9.
We report six cases of carcinoma showing sarcomatous change in the urinary tract examined by conventional histochemistry and immunohistochemistry. All of the cases were transitional cell carcinoma with or without focal squamous cell carcinoma. Sarcomatous components resembling spindle cell sarcoma with a marked myxoid stroma or chondrosarcomatous element were also observed in all cases. The sarcomatous elements were closely associated with the areas of squamous cell carcinoma in three cases. Various histochemical staining procedures demonstrated mesenchymal features in the stroma of sarcomatous areas. By immunohistochemical examination, the epithelial components showed positive reactions for keratin, epithelial membrane antigen and, focally, carcinoembryonic antigen. The sarcomatous components revealed a positive immunoreaction for keratin but lacked other epithelial markers in all cases. Chondrosarcomatous elements in two cases were positive for both keratin and S-100 protein. These findings indicate that sarcomatous elements in carcinoma may represent mesenchymal metaplasia with partial or complete loss of epithelial features. However, further study will be necessary in order to determine whether heterogeneous elements, such as chondrosarcomatous areas, are epithelial or truly mesenchymal in origin.  相似文献   
10.
Young female rats were fed with normal (1.18%) or low (0.05%) calcium diet for 3, 7, 15 or 30 days. The morphology of the parathyroid glands was studied together with serum calcium, parathyroid hormone (PTH), calcitonin and bone mineral density (BMD). As compared to the animals fed with the normal calcium diet, BMD of whole body of the rats fed with the low calcium diet was significantly decreased, whereas the serum PTH level was increased. The parathyroid glands in the rats fed with the low calcium diet were markedly enlarged. In the parathyroid chief cells of the rats fed with the low calcium diet, the Golgi complexes and the cisternae of the granular endoplasmic reticulum were well developed, while the large granules and large vacuolar bodies decreased. Some secretory granules located near the plasma membrane. A proportionally larger increase of the cytoplasm was estimated in the rats fed with the low calcium diet for three and seven days. Enlargement of the cytoplasm and rather frequent mitoses of the chief cells were observed in the rats fed with the low calcium diet for 15 and 30 days. These findings suggest that the rapid bone loss in young rats induced by the low calcium diet is essentially due to stimulated activity of the parathyroid gland. The stimulated gland may be a result of hypertrophy at the early stage and a combination of hypertrophy and hyperplasia at the later stage of calcium deficiency.  相似文献   
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