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81.
An 80-year-old man was under annual surveillance esophagogastroduodenoscopy after endoscopic submucosal dissection(ESD) for early gastric cancer(EGC).Two years after the initial ESD, a 0-Ⅱc type metachronous EGC lesion, 8 mm in size, without an ulcer scar, was found in the gastric antrum.The estimated tumor depth was up to the mucosa, and biopsy revealed well and poorly differentiated adenocarcinoma.ESD was performed for this lesion and en bloc resection with negative margins was achieved.Histopathological examination revealed an adenosquamous carcinoma 8 mm in size invading the deep submucosal layer(1600 μm), with lymphovascular invasion, consistent with the diagnosis of non-curative resection.Additional gastrectomy was recommended for this patient; however, two months after the ESD, preoperative computed tomography revealed multiple liver metastases, and the patient was considered as an unsuitable candidate for surgical resection.Systemic chemotherapy was therefore started; however, the patient died of gastric cancer 27 mo after the second ESD.Early gastric adenosquamous carcinoma localized to the mucosa and submucosa is extremely rare and its clinical behavior is not well known.The present report is very significant in that it underscores the distinct possibility of gastric adenosquamous carcinoma being very aggressive and fatal even when detected at an early cancer.  相似文献   
82.
In this study, we demonstrate that Porphyromonas gingivalis fimbriae use molecules of β2 integrin (CD11/CD18) on mouse peritoneal macrophages as cellular receptors and also show that the β chain (CD18) may play a functional role in signalling for the fimbria-induced expression of interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) genes in the cells. Using a binding assay with 125I-labeled fimbriae, we observed that fimbrial binding to the macrophages was inhibited by treatment with CD11a, CD11b, CD11c, or CD18 antibody but not by that with CD29 antibody. Western blot assays showed that the fimbriae bound to molecules of β2 integrin (CD11/CD18) on the macrophages. Furthermore, Northern blot analyses showed that the fimbria-induced expression of IL-1β and TNF-α genes in the cells was inhibited strongly by CD18 antibody treatment and slightly by CD11a, CD11b, or CD11c antibody treatment. Interestingly, intracellular adhesion molecule 1 (ICAM-1), a ligand of CD11/CD18, inhibited fimbrial binding to the cells in a dose-dependent manner. In addition, ICAM-1 clearly inhibited the fimbria-induced expression of IL-1β and TNF-α genes in the cells. However, such inhibitory action was not observed with laminin treatment. These results suggest the importance of β2 integrin (CD11/CD18) as a cellular receptor of P. gingivalis fimbriae in the initiation stage of the pathogenic mechanism of the organism in periodontal disease.  相似文献   
83.
The mechanism(s) underlying formation of coronary stent thrombus (ST) in chronic phase is yet unclear. Endothelial cells are highly antithrombotic, therefore, it is conceivable that neoendothelial cells (NECs) covering stent struts are damaged and cause ST. This study was performed to examine the role of damaged NECs covering coronary stent struts in the genesis of occlusive or nonocclusive ST in chronic phase.(1) Forty-four patients with acute coronary syndrome (17 females and 27 males) underwent dye-staining coronary angioscopy, using Evans blue which selectively stains damaged endothelial cells, 6 months after bare-metal stent (BMS) deployment. Neointimal coverage was classified into not covered (grade 0), covered by a thin layer (grade 1), and buried under neointima (grade 2) groups. (2) In 7 beagles, the relationships between neointimal thickness and ST were examined 6 months after BMS deployment. (3) The NECs on the struts were stained blue in 4 of 25 patients with grade 2 and in 11 of 20 patients with grade 0/1 (P < 0.05). ST was observed in none of the former and in 5 of the latter (P < 0.05). (4) In beagles, neointimal coverage was grade 0/1 when neointimal thickness was 80.2 ± 40.0 μm, whereas grade 2 when thickness was 184 ± 59.4 μm. ST was observed in 9 of 15 struts with neointimal thickness within 100 μm and in one of 17 struts with thickness over 100 μm (P < 0.05). ST arose from damaged NECs covering the stent struts. NECs may have been damaged due to friction between them and struts due to thin interposed neointima which might have acted as a cushion, resulting in ST.  相似文献   
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85.
Heme oxigenase-1 (HO-1) is known to be an inducible cytoprotective enzyme that copes with oxidative stress. However, changes in HO-1 expression and their association with human diseases have not been studied. To test the hypothesis that the capacity to upregulate HO-1 in response to oxidative stress is an intrinsic marker for susceptibility to coronary atherosclerosis, we assessed stimulation-induced change in HO-1 expression in blood cells in 110 patients who underwent coronary angiography, comparing the results with the extent of coronary atherosclerosis and (GT)(n) repeat polymorphism in the HO-1 gene promoter region, which is believed to affect the gene expression level. The extent of coronary atherosclerosis was assessed by coronary score. Mononuclear cells were incubated with 10 micromol/l hemin or vehicle for 4 h to maximally stimulate HO-1 expression, then the HO-1 expression level was determined by real-time polymerase chain reaction (PCR). The difference between the HO-1 mRNA levels of hemin- and vehicle-treated cells (DeltaHO-1 mRNA) was taken as an index of the capacity to upregulate HO-1 mRNA. The coefficient of variance of DeltaHO-1 mRNA was 7.2%. Consistent with previous studies, DeltaHO-1 mRNA was significantly lower in patients carrying a long (GT)(n) repeat. DeltaHO-1 mRNA negatively and significantly correlated with the coronary score (r(2)=0.50, p<0.01). In conclusion, the capacity to upregulate HO-1 expression may be determined, at least in part, by genetics, and reduced ability to induce HO-1 may be involved in the mechanism of coronary atherosclerosis.  相似文献   
86.
OBJECTIVE: The purpose of the present study was to investigate the possible roles of PvuII and XbaI polymorphisms of the estrogen receptor alpha (ER(alpha)) in bone mineral density (BMD), vertebral fracture, bone loss rate after menopause and response to hormone replacement therapy (HRT). METHODS: All 286 women were grouped according to the genotypes of PvuII or XbaI polymorphisms of the ER(alpha) gene. We compared the BMD Z-score, incidence of vertebral fracture, changes in Z-score after menopause and response of BMD to HRT among the genotypes. RESULTS: Subjects with the PPxx genotype had significantly (P<0.05) lower Z-scores than did subjects with the other genotypes. A negative correlation was observed between the length of time after menopause and the decrease of the Z-score only in women with the pp genotype, suggesting faster bone loss in this group. In the analysis of the ER(alpha) polymorphism with regard to the effect of HRT on BMD, there appears to be a significantly greater increase of BMD (P<0.01 and 0.05) in women with the pp genotype than in those with the Pp or PP genotype. CONCLUSIONS: PvuII and XbaI polymorphisms of the ER(alpha) gene were associated with BMD in postmenopausal Japanese women. Also, the polymorphisms may be useful genetic markers for predicting vertebral fracture in relatively young postmenopausal women. The PvuII polymorphism may be associated with susceptibility to changes in estrogen level.  相似文献   
87.
88.
Primary invasive micropapillary carcinoma of the stomach   总被引:1,自引:0,他引:1  
Reported herein is the case of a 74-year-old man with an unusual gastric carcinoma that developed at the lesser curvature of the stomach. The tumor consisted of small clusters of carcinoma cells surrounded by clear spaces, with histopathology similar to invasive micropapillary carcinoma (IMPC) of the breast. The carcinoma cells, which had downregulation of E-cadherin expression, invaded the subserous tissue and metastasized to the perigastric lymph nodes. IMPC, an unusual subtype of invasive breast carcinoma, is known to have frequent lymph node metastases, resulting in a poor clinical outcome. Although IMPC has been reported in breast, urinary bladder, ureter, lung, salivary gland and colon, to the best of the authors' knowledge this is the first report of IMPC arising in the stomach. Presented here are the clinicopathological features of primary IMPC of the stomach.  相似文献   
89.
In our ongoing series of anatomical studies to determine the three‐dimensional architecture of the human velar muscles, we have previously reported on the palatopharyngeus. The present study deals with the musculus uvulae (MU), in which the positional relationships of its origin to the posterior nasal spine and the palatine aponeurosis, as well as the interrelation between its anatomical status and functions, have yet to be clarified. Macroscopic and microscopic examinations were performed on 25 and 2 cadavers, respectively. In the former, bilateral MUs and their adjacent structures were exposed mainly from the nasal aspect. In the latter, the soft palates embedded in paraffin were cut into frontal and sagittal sections and alternately processed with HE and Azan stains. The left and right MUs adjacent to each other were found to run longitudinally along the midline beneath the nasal aspect of velum. It was overlaid by glandular tissue that increased in amount as it coursed distally. After originating from the oral surface of palatine aponeurosis, it ran backward to cross above the sling formed by the levator veli palatini muscles of both sides and reached the tip of uvula with its muscle fibers intermingled with glandular tissue. Past studies have proposed three functions of MU to enhance the efficiency of velopharyngeal closure: space occupier, stiffness modifier, and velar extensor. All of the above‐described anatomical characteristics of MU could be explained as being adapted for these functions. This implies that MU is actively responsible for maintaining the velopharyngeal closure efficiency. Clin. Anat. 27:1009–1015, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
90.
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