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91.
Diffuse-type giant cell tumor (D-TGCT) is known as a synonym for pigmented villonodular synovitis (PVS), a condition usually found in the large joints. We report an extremely rare case of D-TGCT which was located within the hamstring muscle. The lesion was an incidental finding in a 62-year-old man who underwent positron emission tomography (PET) as part of a staging evaluation for gastric cancer. The lesion was resected. There has been neither metastasis nor recurrence during the 6-month period since resection. This case demonstrates that PVS/D-TGCT may have a high SUV on PET imaging, and for this reason PET may be useful for detecting both the tumor and any recurrence.  相似文献   
92.
OBJECTIVES: The aim of the study was to establish a procedure for early diagnosis and treatment of nonocclusive mesenteric ischemia (NOMI). BACKGROUND: NOMI has a high mortality rate, and early diagnosis and treatment are important for improving survival in patients with this condition. METHODS: The subjects were 22 patients treated at our hospital over 13 years. Diagnostic criteria for NOMI were established based on the first 13 cases. In the 9 more recent cases, we performed abdominal contrast multidetector row computed tomography (MDCT) upon suspicion of NOMI based on these criteria. Imaging allowed definite diagnosis of NOMI, and continuous intravenous high-dose PGE1 administration was initiated immediately after diagnosis (dose, 0.01-0.03 microg/kg per min; mean administration period, 4.8 days). RESULTS: Nine of the first 13 patients died of multiple organ failure associated with multiple intestinal necrosis. These cases suggested that NOMI may develop when 3 of the following 4 criteria are met after cardiovascular surgery or maintenance dialysis in elderly patients: symptoms of the ileus develop slowly from abdominal symptoms, such as an unpleasant abdominal feeling or pain; a requirement for catecholamine treatment; an episode of hypotension; and slow elevation of the serum transaminase level. In the 9 recent cases, definite diagnosis was made from spasm of the principal arteries in arterial volume rendering and curved planar reformation MDCT images. Early treatment with PGE1 prevented acute-stage NOMI in 8 of the 9 cases. CONCLUSIONS: Early diagnosis of NOMI is possible using the above criteria and MDCT, and initiation of PGE1 treatment may increase survival in patients with NOMI.  相似文献   
93.
A 62-year-old woman was referred to our hospital for bilateral renal stones. Ultrasonography (US) and computed tomography (CT) revealed bilateral staghorn calculi and atrophic left kidney. She had extracorporeal shock-wave lithotripsy (ESWL) for right renal stone during the first 6 months. However, ESWL was not effective and the patient did not want to continue this treatment. Her stone was composed of cystine. We started oral administration of alkaline citrate. Then massive residual stones were completely dissolved during the next 32 months.  相似文献   
94.
Melanoma is commonly associated with multi-organ metastasis, and bone is a frequent metastatic site for melanoma. However, the mechanism responsible for such melanoma-induced bone metastasis is still poorly understood. In the present study, the intracardiac inoculation of leukemia inhibitory factor (LIF)-producing human melanoma-derived cells (SEKI) developed osteolytic bone destruction in male BALB/cA-nu/nu nude mice. To elucidate the role of LIF in melanoma-induced osteolysis, cells were prepared in which the expression of LIF was reduced using a siRNA technique from the parent SEKI cells. Osteoclastogenesis was induced in the co-culture of LIF and/or SEKI cells with osteoblastic stromal cells in vitro, whereas the LIF-reduced SEKI cells did not induce osteoclastogenesis. The intracardiac inoculation of LIF-reduced SEKI cells resulted in a significant reduction in the incidence and number of bone metastasis in comparison to those in the mice inoculated with the parent SEKI cells. The expression of LIF was found in seven of nine human melanoma-derived cell lines, suggesting that LIF expression is a universal event in melanoma. These findings suggest that a potential role for LIF in the melanoma-induced bone metastasis possibly through the stimulation of osteoclastogenesis. LIF might therefore be a potentially effective drug target in the treatment of bone metastasis in melanoma.  相似文献   
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97.

Background

Serous oligocystic adenoma (SOA), a rare pancreatic neoplasm, is generally a benign lesion without the necessity of surgery. Preoperatively, it is difficult to discriminate SOA from mucinous cystic neoplasm (MCN), which essentially needs surgical treatment. The purpose of this study was to evaluate the cyst wall thickness of SOAs and MCNs for preoperative differential diagnosis.

Methods

We experienced three cases of SOAs with typical histopathological features. The cyst wall thickness of the SOAs was evaluated in the area protruding out of the pancreas and was compared with that of 13 MCNs histopathologically. The same evaluation and comparison were conducted on preoperative computed tomography (CT) images retrospectively.

Results

The SOAs had a uniformly thin cyst wall measuring less than 1 mm. In contrast, the largest area of a cyst wall in MCNs ranged from 2.5 to 10.0 mm. On CT images, all but one of the MCNs showed a detectable cyst wall, while the cyst walls were hardly recognizable in two of the three SOAs.

Conclusions

For preoperative differentiation between SOAs and MCNs, the evaluation of cyst wall thickness may be an important tool and may contribute to the decision of treatment strategy.  相似文献   
98.
Evaluation of the relationship between clinicopathological and immunohistochemical risk factors for liver metastasis, including CD10 expression, is meaningful in colorectal carcinoma (CRC). The purpose of the present study was to clarify what kind of risk factors are significant and independent factors for the development of liver metastasis in CRC. Sixty cases of advanced CRC with synchronous liver metastasis and sixty cases of advanced CRC without liver metastasis at least 5 years after resection of the primary CRC were randomly selected. We analysed the clinicopathological factors and the expression of four biological factors, CD44, transforming growth factor alpha (TGF-alpha), vascular endothelial growth factor (VEGF) and CD10, by immunohistochemistry. Univariate analysis revealed that the incidence of vascular invasion, the incidence of lymph node metastasis and the expression of CD44, TGF-alpha, VEGF and CD10 were all significantly higher in the cases of CRC with liver metastasis than in cases of non-metastatic CRC. Logistic regression analysis showed that lymph node metastasis, the expression of CD10 and the expression of VEGF were significant factors and independent of the other variables. If all three markers are positive, the probability of liver metastasis becomes 92.7%. In this study, lymph node metastasis, CD10 and VEGF were all found to be significant risk factors for the development of liver metastasis in the cases of CRC. These risk factors according to multivariate analysis are candidate markers for predicting the development of liver metastasis.  相似文献   
99.
Pyloric-gland type adenoma of the gallbladder is formed by proliferation of glands resembling pyloric glands, morphologically. No previous report has described the cellular phenotype and differentiation of pyloric-gland type adenoma of the gallbladder, using CD10 as a marker of proper biliary phenotype. Immunostainings were performed for mucin markers such as MUC5AC, human gastric mucin (HGM) for gastric foveolar type epithelium, MUC6, M-GGMC-1 for pyloric-gland type and MUC2 for intestinal goblet-cell type, and for CD10 as a proper biliary type marker on 58 pyloric-gland type adenomas of the gallbladder, as well as for p53, Ki-67 and CDX2. The percentage (X) of reactive cells in relation to the total number of tumor cells was estimated semi-quantitatively, and divided into four categories: X=0% (negative), 0%or=30%. CDX2 expression was considered to be positive when the percentage of positively stained cells was >or=10%. Out of the 58 pyloric-gland type adenomas, >or=30% of adenoma cells were positive for MUC5AC in 22 (38%) tumors, HGM in 29 (50%), MUC6 in 58 (100%), M-GGMC-1 in 54 (93%), MUC2 in none (0%), and CD10 in 20 (34%). MUC6 (P<0.001) and M-GGMC-1 (P<0.001) mucins were detected more frequently in pyloric-gland type adenomas, and CD10 expression was significantly decreased, compared with normal gallbladder epithelium (P=0.006). P53 overexpression was not found in any of the 58 tumors, including two adenomas with carcinomatous foci. The mean number of Ki-67-positive cells was 10.3+/-5.8%. CDX2 expression was judged as negative in all 58 pyloric-gland type adenomas. In pyloric-gland type adenomas of the gallbladder, expression of pyloric-gland type mucins was observed with a high frequency, whereas intestinal goblet-cell mucins were rarely seen. In addition, co-expression of gastric foveolar type mucins and CD10 was also demonstrated. Pyloric-gland type adenomas of the gallbladder show a differentiation toward pyloric glands in terms of immunohistochemistry, as well as morphology, accompanied by co-expression of gastric foveolar and native biliary phenotypes.  相似文献   
100.
MUTYH is a mammalian DNA glycosylase that initiates base excision repair by excising adenine opposite 8-oxoguanine and 2-hydroxyadenine opposite guanine, thereby preventing G:C to T:A transversion caused by oxidative stress. Recently, biallelic germ-line mutations of MUTYH have been found in patients predisposed to a recessive form of hereditary multiple colorectal adenoma and carcinoma with an increased incidence of G:C to T:A somatic mutations in the APC gene. In the present study, a systematic histologic examination revealed that more spontaneous tumors had developed in MUTYH-null mice (72 of 121; 59.5%) than in the wild type (38 of 109; 34.9%). The increased incidence of intestinal tumors in MUTYH-null mice (11 tumors in 10 of 121 mice) was statistically significant compared with the wild type (no intestinal tumors in 109 mice). Two adenomas and seven adenocarcinomas were observed in the small intestines, and two adenomas but no carcinomas were found in the colons. In MUTYH-null mice treated with KBrO(3), the occurrence of small intestinal tumors dramatically increased. The mean number of polyps induced in the small intestines of these mice was 61.88 (males, 72.75; females, 51.00), whereas it was 0.85 (males, 0.50; females, 1.00) in wild-type mice. The tumors developed predominantly in the duodenum and in the upper region of the (jejunum) small intestines. We conclude that MUTYH suppresses spontaneous tumorigenesis in mammals, thus providing experimental evidence for the association between biallelic germ-line MUTYH mutations and a recessive form of human hereditary colorectal adenoma and carcinoma.  相似文献   
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