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21.
A schwannoma is a tumor that develops on peripheral nerves or spinal roots. Although any part of the body can be affected, the breast is a quite unusual site for schwannomas. We report herein a case of schwannoma presenting as a breast tumor. In the current case, the tumor showed both clinically and mammographically as a well-defined breast mass. Of interest, sonographically, the well-defined mass appeared to be located in subcutaneous tissue, not in breast parenchyma, and this finding was confirmed histopathologically. These findings indicate the possibility that a schwannoma arising from subcutaneous breast tissue can show exophytic growth to the breast and appear as a breast tumor. In other words, our case implies the possible presence of a “pseudo” breast schwannoma.Key words: Schwannoma, Breast, Breast cancerA schwannoma is a relatively rare neoplasm that occurs from Schwann cells of the peripheral nerve sheath.13 Although schwannomas may occur in any organ, a breast schwannoma is extremely rare and accounts only 2.6% of schwannomas.14 We report herein a case of schwannoma suspected to be a breast tumor. The concern with breast schwannoma is a differential diagnosis, since on mammogram it sometimes resembles a breast cancer or tumor.  相似文献   
22.
T cells of the small intestine, including Th17 cells, are critically involved in host protection from microbial infection, and also contribute to the pathogenesis of small bowel inflammatory disorders. Accumulating evidence suggests that mesenteric lymph nodes (MLNs) play important roles in gut‐tropic T‐cell generation, although it is still unclear if MLNs are involved in the pathogenesis of small intestine inflammation. To address this issue, we analyzed the roles of both MLNs and Peyer's patches (PPs) by evaluating MLN‐ or PP‐deficient mice in an experimental model of small intestine inflammation, induced by CD3‐specific mAb injection. Interestingly, MLNs, but not PPs, were essential for the pathogenesis of intestinal inflammation, in particular the accumulation and infiltration of CD4+ T‐cell populations, including Th17 cells, from the blood. In addition, CD4+ T‐cell accumulation was dependent on the function of the α4β7 integrin. Furthermore, MLN removal led to a significantly reduced number of peripheral α4β7+ CD4+ effector memory T cells under normal conditions, suggesting that MLNs may play a role in maintaining the number of gut‐tropic CD4+ effector memory T cells circulating in the blood. Taken together, the present study highlights the important role of MLNs in contributing to the pathogenesis of small intestine inflammation.  相似文献   
23.

Background  

In this report, laparoscopy-assisted proximal gastrectomy (LAPG) and gastric tube reconstruction using a mini-loop retractor (MLR) is described for the treatment of early gastric cancer.  相似文献   
24.
A case of rapidly progressed undifferentiated renal cell carcinoma in a 2 2/12-month-old boy is reported. The histology is characterized by sarcomalike spindle and pleomorphic cells and bizarre giant cells, thus creating many difficulties in the differential diagnosis. The diagnosis of renal cell carcinoma was established on the basis of tubular formation by clear and granular cells observed in a few discrete areas.

The literature on renal cell carcinoma occurring under 10 years of age was reviewed, with special attention given to histological typing. It is general & believed that renal cell carcinoma in children is well differentiated, but 2 of 39 cases reviewed were undifferentiated. We conclude that renal cell carcinoma in infants or young children may have an undifferentiated, atypical histological appearance and can progress rapidly. The differential diagnosis from anaplastic Wilms' tumor and sarcomatous tumors of the kidney in children is discussed.  相似文献   
25.
Laparoscopy-assisted gastrectomy has been increasingly reported as the treatment of choice for early gastric cancer. However, there is little information regarding the benefits of laparoscopy-assisted distal gastrectomy (LADG). LADG and conventional open distal gastrectomy (DG) for early gastric cancer were compared in terms of operative outcome, recovery of bowel function, complications, and changes in body weight. Thirty-four patients underwent LADG for early gastric cancer. These patients were compared with 31 patients who underwent DG during the same period. For estimating gastrointestinal motility recovery, 20 radiopaque markers were inserted into the duodenum during surgery, and abdominal X-rays were taken daily until all markers were seen in the ascending colon. Age, gender, and histologic differentiation of the lesions were matched. The LADG group required a significantly longer operative time and the dissection of fewer lymph nodes. Postoperative hospital stay and the occurrence of postoperative complications (ileus) were significantly shorter and less frequent in the LADG group. The LADG group showed a more rapid recovery of gastrointestinal motor function compared with the DG group during the early postoperative period. Body weight 24 months after LADG was about 100% of pre-illness weight, but no further weight change was encountered in the DG group. For selected patients with early gastric cancer, LADG with lymphadenectomy can provide a rapid recovery and good quality of life without compromising the cure rate.  相似文献   
26.
In this study, inducible nitric oxide synthase (iNOS) expression in a series of 158 human primary brain tumors was analyzed. To gain some insight into the biological significance of iNOS expression in tumor cells, comparative immunohistochemical analyses were employed to characterize the expression of iNOS, superoxide dismutase (SOD) proteins (SOD1 and SOD2), Ki-67 antigen (MIB-1) and p53 protein in these cells. Sixteen (39.0%) of the 41 glioblastoma multiforme (GBM) specimens showed iNOS immunoreactivity. Positive immunoreactions with iNOS were also detected in 2/8 anaplastic astrocytomas, 1/17 astrocytomas, 1/14 medulloblastomas and 1/11 primitive neuroectodermal tumors, but no positive reactions were observed in oligodendrogliomas (0/11), ependymomas (0/5), schwannomas (0/21), meningiomas (0/23) or pituitary adenomas (0/7). The MIB-1 labeling index of GBMs that expressed iNOS was significantly higher than that of GBMs that did not (0.025< P <0.05, Wilcoxon rank-sum test). Unlike iNOS-negative tumors, all iNOS-positive tumors coexpressed SOD1 or SOD2. In particular, there was a significant correlation between iNOS induction and SOD1 expression (P =1.65x10(-10), Fisher's exact test) in GBM specimens. There was no significant relationship between iNOS and p53 protein in any type of primary brain tumor (P >0.05, Fisher's exact test). No significant immunohistochemical reactions with iNOS, MIB-1 or p53 protein were observed in normal brain tissue sections. We conclude that primary brain tumors express iNOS, and that iNOS expression in brain tumor cells may depend, in part, on cellular proliferation potential. Based on the fact that SOD1 scavenges oxidative-stress species originating from large amounts of nitric oxide (NO) produced by iNOS, iNOS-expressing brain tumor cells may protect themselves against NO cytotoxicity by overinducing SOD1.  相似文献   
27.
To clarify the trophic mechanism of residual anterior horn cells affected by sporadic amyotrophic lateral sclerosis (SALS) and familial ALS (FALS) with superoxide dismutase 1 (SOD1) mutations, we investigated the immunohistochemical expression of hepatocyte growth factor (HGF), a novel neurotrophic factor, and its receptor, c-Met. In normal subjects, immunoreactivity to both anti-HGF and anti-c-Met antibodies was observed in almost all anterior horn cells, whereas no significant immunoreactivity was observed in astrocytes and oligodendrocytes. Histologically, the number of spinal anterior horn cells in ALS patients decreased along with disease progression. Immunohistochemically, the number of neurons negative for HGF and c-Met increased with ALS disease progression. However, throughout the course of the disease, certain residual anterior horn cells co-expressed both HGF and c-Met with the same, or even stronger intensity in comparison with those of normal subjects, irrespective of the reduction in the number of immunopositive cells. Western blot analysis revealed that c-Met was induced in the spinal cord of a patient with SALS after a clinical course of 2.5 years, whereas the level decreased in a SALS patient after a clinical course of 11 years 5 months. These results suggest that the autocrine and/or paracrine trophic support of the HGF-c-Met system contributes to the attenuation of the degeneration of residual anterior horn cells in ALS, while disruption of the neuronal HGF-c-Met system at an advanced disease stage accelerates cellular degeneration and/or the process of cell death. In SOD1-mutated FALS patients, Lewy body-like hyaline inclusions (LBHIs) in some residual anterior horn cells exhibited co-aggregation of both HGF and c-Met, although the cytoplasmic staining intensity for HGF and c-Met in the LBHI-bearing neurons was either weak or negative. Such sequestration of HGF and c-Met in LBHIs may suggest partial disruption of the HGF-c-Met system, thereby contributing to the acceleration of neuronal degeneration in FALS patients.  相似文献   
28.
Among 448 patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), 40 patients (8.9%) had been involved in one or more automobile accidents during the preceding 5 years. The main cause of these accidents was falling asleep while driving. Excessive sleepiness during driving was associated with an Epworth sleepiness scale (ESS) score of > 11 and/or an apnea-hypopnea index (AHI) of > 15. The automobile accident rate among 182 patients with severe OSAHS (AHI > 30) was significantly higher than the rate among 106 simple snorers (AHI < 5). Although four of the simple snorers were involved in automobile accidents, their ESS scores were all very high (15 or more).  相似文献   
29.
Meningeal melanocytoma is a rare pigmented tumor originating from the melanocytes that generally occurs in the posterior fossa and the spinal cord. Although it is known as a relatively benign tumor, some recurrences have been reported. We report two cases of spinal meningeal melanocytoma with immunohistochemical and ultrastructural studies. In addition, we include a summary of published cases since the first case of Limas and Tio in 1972.  相似文献   
30.
We have produced a novel rat IgG(2a) monoclonal antibody against a stage-specific fetal brain glycoprotein of 68 kDa (FGP68), and succeeded in applying it to staining paraffin sections. To gain some insight into the pathobiological significance of this FGP68, this monoclonal antibody was used in immunohistochemical studies to compare the expression of FGP68 and Ki-67 antigen (MIB-1) in 235 primary brain tumors. Approximately half of the glioblastomas multiforme (GBMs) (44/75) and anaplastic astrocytomas (9/17) as well as some astrocytomas (5/30), medulloblastomas (2/14) and primitive neuroectodermal tumors (2/10) had tumor cells that expressed FGP68; however, pilocytic astrocytomas (0/7), oligodendrogliomas (0/15), ependymomas (0/6), schwannomas (0/21), meningiomas (0/22) and pituitary adenomas (0/18) did not express FGP68. The values of the MIB-1 labeling index were statistically higher in GBMs (0.005< P<0.01, Wilcoxon rank-sum test) and anaplastic astrocytomas (0.025< P<0.05) that expressed FGP68 than in those that did not. Normal brain tissue from 20 individuals aged 3-75 years was negative for FGP68 and MIB-1. We conclude that primary brain tumors express FGP68, one of the oncofetal proteins derived from fetal brain, and that FGP68 expression in certain brain tumor cells may depend, in part, on proliferation potential. Based on the possibility that the stage-specific FGP68 plays an important role in brain embryogenesis, some of FGP68-expressing tumor cells might phylogenetically revert to more primitive cells.  相似文献   
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