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71.
Acute-type lateral ridge defects (25 mm × 6 mm × 5 mm) were bilaterally created in the mandibles of four dogs (two defects per animal). The defects were reconstructed with particulate autologous bone and covered with a microperforated titanium membrane (Ti-honeycomb membrane, TiHM) or an existing conventional titanium mesh as control. The samples were dissected after 16 weeks postoperatively and processed for radiographic, histologic, and histomorphometric analyses. Regenerated tissue and bone volume were significantly larger in the TiHM group than in the control group (p = 0.05; p = 0.049). In contrast, bone mineral density was similar between the two groups. Histomorphometric analysis revealed that the regenerated bone area and calcific osseous area were larger in the TiHM group than in the control group; however, the differences were not significant. The efficacy of TiHM was generally satisfactory with the potential to become a standard tool for the GBR procedure; however, early membrane exposure will be a major problem to overcome.  相似文献   
72.
Background/ObjectivesAccording to the revised international intraductal papillary mucinous neoplasm (IPMN) guidelines (2017), the indication for surgery is based on risk classification. However, some IPMNs with high-risk stigmata (HRS) can be observed for long periods without resection. Hence, we need to reconsider the risk stratification, and this study aimed to propose a novel risk stratification for HRS-IPMNs.MethodsWe enrolled 328 patients diagnosed with IPMN using endoscopic ultrasound between 2012 and 2019. We compared clinicopathological features between HRS and worrisome features (WF) and evaluated outcomes of HRS-IPMN.ResultsFifty-three patients (HRS 38, WF 15) underwent resection at initial diagnosis and 275 patients were observed. Following observation for 30 months, 22 patients (17 HRS, 5 WF) underwent resection. Analysis of resected IPMNs (n = 75) revealed that HRS had dominantly pancreatobiliary mucin subtype. Pancreatobiliary-type IPMN had larger nodule sizes and lymphatic invasion and high recurrence with poor prognosis. Seventy-four patients were diagnosed with HRS, 55 underwent resection, and 19 continue to be observed. The resected group had larger nodule sizes (median 8 mm vs. 5 mm; P = 0.060), whereas the observed group had more main pancreatic duct (MPD) dilation (median 10 mm vs. 5 mm; P = 0.005). In the resected HRS group, only patients with MPD dilation ≥10 mm (n = 10) had no recurrence but had a favorable prognosis compared with those nodule size ≥5 mm (n = 45).ConclusionsLarge nodule size may be associated with pancreatobiliary subtype and poor prognosis; however, patients with MPD dilation ≥10 mm with nodule size <5 mm did not require resection.  相似文献   
73.
The enzymes, such as TNSALP regulate bone mineralization, and the mineralization inhibitor inorganic pyrophosphate (PPi) plays a central role in the process. NPP1 and ANK increase PPi concentration in the extracellular matrix, while TNSALP hydrolyzes PPi. The analyses using knock-out mice demonstrated that NPP1 and ANK, and TNSALP are antagonistic regulators for PPi. Concerted regulation of PPi by TNSALP, NPP1, and ANK, leads bone mineralization to be regulated strictly.  相似文献   
74.
We report a case of spontaneous rupture of a giant cavernous hemangioma of the liver arising from the caudate lobe, with extrahepatic growth, in a 67-year-old man. At emergency laparotomy, partial resection of the caudate lobe was performed and the hemangioma was found to measure 13 ×12×8 cm. The patient had a 10-year history of severe asthma requiring steroid therapy. To investigate the risk factors for spontaneous rupture of hepatic hemangioma, we compared the characteristics of patients with ruptured and non-ruptured lesions showing extrahepatic growth reported in the Japanese literature. Lesions with a diameter ≥4 cm located on the surface of the liver or showing extrahepatic growth appear to have a high risk of spontaneous rupture if the patient receives steroid therapy for a coexisting disorder. Even in patients who have not received steroid therapy, hemangiomas≥7–8 cm in diameter located in the left lobe with extrahepatic growth may also have a high risk of rupture. The treatment of hepatic hemangioma should be decided on the basis of the size and the location, and on the requirement for steroid therapy.  相似文献   
75.
76.

Background

IL-10 is a major anti-inflammatory cytokine that prevents inflammation-mediated tissue damage. We characterized the production of IL-10 by sinonasal tissue cells following exposure to Staphylococcus aureus enterotoxin B (SEB), which elicits cellular responses and is associated with the pathogenesis of eosinophilic chronic rhinosinusitis (ECRS).

Methods

Dispersed nasal polyp (NP) cells and uncinate tissue (UT) cells were prepared from patients with CRS with and without NP, respectively. Cells were incubated with SEB, and then the levels of IL-10 in the cell supernatants were determined. The effect of neutralizing IL-10 on SEB-induced IL-5, IL-13, IFN-γ, and IL-17A production was examined. Expression of IL-10 in NPs was also determined.

Results

IL-10 was expressed in infiltrating inflammatory cells in NPs. NP cells, especially non-adherent NP cells, produced substantial amounts of IL-10 in response to SEB. Although baseline production of IL-10 was significantly higher in NP cells than UT cells, the degree of IL-10 response to SEB was not significantly different between the cell types. The degree of IL-10 production was negatively correlated with the degree of eosinophilia both in tissues and peripheral blood whereas positively correlated with the 1-s forced expiratory volume/forced vital capacity ratio. Patients with severe ECRS displayed a significant decrease in IL-10 production compared with those with non-ECRS. IL-10 neutralization significantly augmented SEB-induced IL-13 and IFN-γ production by NP cells.

Conclusions

Impaired IL-10 production in response to SEB in NP may exacerbate the pathophysiology of ECRS including eosinophilia and lower airway obstruction.  相似文献   
77.
Fibroblast growth factor 23 (FGF23) functions in an endocrine fashion and requires α‐Klotho to exert its effects on the target organs. We have recently demonstrated that the human placenta also expresses α‐Klotho, which led us to hypothesize that FGF23 may exert effects on the placenta. Immunohistochemical analysis demonstrated the expression of FGF receptor 1 (FGFR1) as well as that of α‐Klotho in the feto‐maternal interface of both mouse and human normal‐term placentas, which suggested that these areas might be receptive to FGF23. Therefore, we next investigated whether FGF23 has some roles in the placenta using Hyp mice with high levels of circulating FGF23. Hyp and wild‐type (WT) females were mated with WT males, and the mothers and their male fetuses were analyzed. FGF23 levels in Hyp mothers were elevated. FGF23 levels were about 20‐fold higher in Hyp fetuses than in Hyp mothers, whereas WT fetuses from Hyp mothers exhibited low levels of FGF23, as did fetuses from WT mothers. We analyzed the placental gene expression and found that the expression of Cyp24a1 encoding 25OHD‐24‐hydroxylase, a target gene for FGF23 in the kidney, was increased in the placentas of fetuses from Hyp mothers compared with fetuses from WT mothers. In an organ culture of WT placentas, treatment with plasma from Hyp mothers markedly increased the expression of Cyp24a1, which was abolished by the simultaneous addition of anti‐FGF23 neutralizing antibody. The direct injection of recombinant FGF23 into WT placentas induced the expression of Cyp24a1. The increase in the placental expression of Cyp24a1 in fetuses from Hyp mothers resulted in decreased plasma 25‐hydroxyvitamin D levels. These results suggest that increased levels of circulating FGF23 in pathological conditions such as Hyp mice exerts direct effects on the placenta and affects fetal vitamin D metabolism via the regulation of Cyp24a1 expression. © 2014 American Society for Bone and Mineral Research.  相似文献   
78.
A case of plasma cell leukaemia of non-producer type is described. The patient presented with typical clinical features of plasma cell myeloma, including multiple osteolytic lesions, hypercalcaemia, renal failure and reduced polyclonal immunoglobulins, except that M-component was not detected in either the serum or urine. Morphological examinations showed a plasmacytoid appearance of the neoplastic cells, while immunological studies failed to detect cytoplasmic immunoglobulin or secretory capacity. The surface phenotype of CD38+, PCA-1+, DR-, CD20-, CD24-, CD9-, CD10- and surface immunoglobulin- was compatible with mature plasma cells. Chromosomal analysis showed the 14q+ marker due to translocation (6;14) and deletion of the short arm of chromosome 1. Analysis of immunoglobulin genes revealed the presence of heavy chain gene rearrangement, but the light chain genes, both kappa and lambda, remained in germline configuration. Such defective immunoglobulin gene rearrangement may be responsible for the failure of immunoglobulin biosynthesis and secretion by the neoplastic plasma cells. Furthermore, it is suggested that the morphological and phenotypic development of B cells may not necessarily depend on immunoglobulin light chain gene rearrangement, and that the oncogenic event in myeloma may occur at an earlier stage of B cell differentiation.  相似文献   
79.
A highly sensitive and precise radioimmunoassay system for plasma cholecystokinin (CCK) was developed with the anli-CCK-8 specific antiserum which raised against N-terminal amino acids residue of sulfated CCK-8 and reacted with CCK-8, CCK-33, and CK-39 but not with gastrin and its related peptides. Mean concentration of the fasting plasma CCK determined with this method using CCK-8 as standard was 12.9 ± 5.9 pg/ml in normal subjects (n = 26), and in patients with hepatic cirrhosis it was significantly higher (36.7 ± 16.9 pg/ml, n = 9, p < 0.01) than in normal subjects. In six young healthy volunteers, intraduodenal infusion of fat caused a significant increase ( p < 0.05) of plasma CCK from a basal level of 8.0 pg/ml to a peak of 43.0 ± 12.0 pg/ml at 20 min after starting of infusion. In the same subjects, a significant increase of plasma CCK was also observed by amino acids infusion, but no elevation of plasma CCK level was found during intraduodenal acidification.  相似文献   
80.
A new modality is necessary to prevent recurrence of superficial bladder cancer after complete transurethral resection (TUR) because of the high recurrence rate even with current prophylaxis protocols. Prostaglandins (PGs) are known to be produced more in transitional cell carcinoma, and etiologically bladder cancer risk is negatively associated with the intake of non-steroidal anti-inflammatory drugs (NSAIDs), which inhibit cyclooxygenase (COX), the rate-limiting enzyme of the PG production. We have shown the chemopreventive effect of piroxicam, an NSAID, on the N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced rat bladder cancer model. To avoid gastrointestinal side effects of regular NSAIDs, we also showed the chemopreventive effect of nimesulide, a selective inhibitor of the second isoform of COX, COX-2, which does not affect COX-l house-keeping activity in gastrointestinal mucosa on the same model. We also observed induction of COX-2 protein in the rat bladder tumor. In this study, we screened COX-2 protein expression in primary superficial bladder cancer tissues, to elucidate if COX-2 selective inhibitors can be a candidate chemopreventive agent for bladder cancer recurrence. Five and 6 samples of superficial bladder cancer cases with and without recurrence after complete TUR were examined by immunohistochemical analysis. We found more COX-2 protein positive samples in the cases with recurrence than in cases without recurrence. Even though the number of cases examined is small, this result supports our hypothesis that COX-2 contributes to superficial bladder cancer recurrence, thus, selective COX-2 inhibitors can be a candidate chemopreventive agent for the recurrence.  相似文献   
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