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821.
We report a case of a clear cell adenocarcinoma arising from a giant cystic adenomyosis, with immunohistochemical analysis of p53 and laminin-5 gamma2 chain overexpression. Microscopically, not only clear cell adenocarcinoma showing myometrial invasion but also single-layered clear cell adenocarcinoma cells lining the cyst wall were observed. Transition from these single-layered tumor cells to papillary proliferative lesions of various degrees was recognized. Moreover, these tumor cells were continuous with minimal atypical cells. Although the tumor cells within the uterus showed a low positive cell ratio for p53, the metastatic foci showed a remarkable p53 overexpression. Laminin-5 gamma2 chain expression was low in papillary proliferation and high in myometrial invasion and metastatic foci. The single-layered tumor cells showing non-invasive proliferation also contained laminin-5 gamma2 chain-positive cells. When non-invasive tumor cells were considered to be at an early stage in tumor progression, some tumor cells had already acquired an invasive feature. p53 overexpression was not related to expression of the laminin-5 gamma2 chain.  相似文献   
822.
Expression of hepatocyte nuclear factor-1beta (HNF-1beta) is significantly up-regulated in ovarian clear cell carcinoma (CCC). The mechanism of up-regulation, however, remains unclear. It has been recognized that hypomethylation of specific gene promoters is involved in aberrant gene expression in carcinogenesis. In the present study, ovarian CCCs were examined whether there was a correlation between the methylation and expression status of HNF-1beta, using combined bisulfite restriction analysis (COBRA), bisulfite-sequencing and immunocyto/histochemistry. In 2 CCC cell lines, hypomethylation of HNF-1beta CpG island strongly correlated with HNF-1beta expression, at both the mRNA and protein levels. In archival surgical specimens, 20 of 20 CCCs were immunohistochemically positive for HNF-1beta, whereas none of 20 serous adenocarcinomas (SAs) or 12 normal ovaries were positive for it. By COBRA, methylation of HNF-1beta CpG island was less frequently detected in CCCs (8 of 20, 40%) than SAs (18 of 20, 90%) or normal ovaries (12 of 12, 100%) (p < 0.01), which was confirmed by bisulfite-sequencing. In addition, HNF-1beta hypomethylation correlated with a high HNF-1beta immunostaining score in CCCs. These results strongly suggest that hypomethylation of the HNF-1beta CpG island participates in the HNF-1beta up-regulation in ovarian CCC.  相似文献   
823.
824.
Our case report describes a patient with clear cell fallopian tube carcinoma (histological grade 3; stage (FIGO): III c.) associated with an endometrial cyst of the tube wall. Received: 25 May 2001 / Accepted: 25 June 2001  相似文献   
825.
We report a case of an incidental combined carcinoma of the gallbladder in a 66-year-old woman who underwent cholecistectomy for gallstones.

The neoplasm was mainly constituted by a clear cell component and a small cell, chromogranin-positive one; it also showed some areas of conventional adenocarcinoma and foci of vascular invasion. The patient died after 3 years following treatment with combination chemotherapy.

The histologic and immunohistochemical profile of the lesion is described, together with a brief review of the pertinent bibliography.  相似文献   

826.
A clear cell mesothelioma presenting as an incarcerated ventral abdominal hernia in a 67-year-old man who had no history of asbestos exposure is described. The cause of the cytoplasmic clearing was the presence of large amounts of glycogen. Although uncommon, this variant of mesothelioma is important to recognize because it can be easily confused with other clear cell tumors involving the serosal membranes. Significant recent advances in the immunohistochemistry of epithelioid mesothelioma are briefly reviewed because immunohistochemical studies can be helpful in establishing the correct diagnosis.  相似文献   
827.
BACKGROUND: Clear cell adenocarcinoma (CCA) of the vagina and cervix in young women is associated with prenatal exposure to diethylstilbestrol (DES). Parenchymal pulmonary metastases are known to occur following treatment of the primary tumor. Most recurrences present within 2 to 3 years of the initial diagnosis. CASE: This is a case report of a solitary endobronchial clear cell adenocarcinoma occurring 15.3 years after the initial diagnosis of DES-induced CCA. CONCLUSIONS: This case suggests that management of clear cell cancer survivors should involve long-term follow-up because of the potential for the appearance of a new focus of clear cell adenocarcinoma.  相似文献   
828.
Clear cell tumor of the lung is a rare benign tumor. We report herein a case of clear cell tumor of the lung. A 45 year-old woman with a round mass lesion of approximately 2 cm diameter on chest X-ray underwent a thoracotomy. Pathologic examination revealed sheets of large round or polygonal cells with clear cytoplasm and immunoreactive positivity for HMB-45 and vimentin. Investigation with abdominal CT scans showed no evidence of renal disease, and the tumor was diagnosed as clear cell tumor of the lung.  相似文献   
829.
Renal cell carcinoma (RCC) has the highest rate of occurrence within the US when compared with other countries. Recent advances in the basic research and molecular diagnostics of this malignancy have revealed that RCC is not a single disease, but it is a mixture of several types of malignancies with unique molecular mechanisms and pathological attributes. RCC is now divided into clear cell carcinoma (80% of all kidney cancers), papillary type 1 and papillary type 2 neoplasms (10-15% of all RCC patients) and RCC with chromophobic and oncocytic features, called the Birt-Hogg-Dube (BHD) subtype, in roughly 5% of all patients. Apart from these, neoplasms such as the tuberous sclerosis (TSC) syndrome may occur with a mixed pathological features with a renal presentation. In this review, molecular evidence, both direct and indirect, published so far on all these RCC subtypes have been analyzed to find out whether there is any common thread that could run through these disparate malignancies that happen to occur in a single organ, i.e., the kidney. We believe that the role played by the expression and certain non-traditional activities of the cabonic anhydrase (CA) family members, along with the differing levels of hypoxia induced within these tumors may be the most common denominators. Evidence is presented focusing on how the CA family members could participate in the genesis and progression of each and every one of these RCC subtypes and how their function could be influenced by hypoxia, activities of receptor type protein tyrosine kinases and certain other pre-disposing factors. These rationalizations point towards a unified hypothesis that may help explain the occurrence of all these RCC subtypes in a molecular manner. We hope that these analyses would a) stimulate further studies aimed toward a better understanding of the role played by carbonic anhydrases in RCC subtypes and b) would pave way to a better and rationally designed therapies to interfere with their function to benefit patients with RCC and possibly other cancers.  相似文献   
830.
Patients with ovarian cancer with clear cell histology often have venous thromboembolism (VTE) even before surgery. In view of the possible association between clear cell histology and VTE in endometrial cancer, we measured the plasma levels of thrombin-antithrombin III complex (TAT) and D-dimer (DD) in the preoperative examinations of a patient with clear cell adenocarcinoma of the endometrium. Plasma TAT and DD were both highly elevated, though the patient had no symptoms of VTE or risk factors such as obesity or diabetes mellitus. Ultrasound Doppler examination and lung perfusion scintigraphy just before surgery revealed a thrombosis in the left popliteal vein and a pulmonary embolism. After implanting an inferior vena cava filter to prevent a fatal embolism of the lung, we performed abdominal total hysterectomy, bilateral salpingo-oophorectomy, and sampling of the pelvic lymph nodes. The VTE gradually disappeared and the plasma levels of TAT and DD returned to normal after surgery. Possibly, the VTE in this patient may have been associated with the clear cell histology.  相似文献   
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