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91.
BACKGROUND/AIMS: Preoperative information on arterial anatomy in the peripancreatic and hepatic areas is valuable to any surgeon performing pancreatoduodenectomy. METHODOLOGY: Between 1994 and 1998, 49 patients with periampullary cancer (31 distal bile duct and 18 ampullary tumors) underwent visceral angiography and radical pancreatoduodenectomy with lymphadenectomy. Surgically "significant" arterial variations and their effects on operative management and results were examined retrospectively. RESULTS: Arterial variations were found in 18 patients (37%); 15 (31%) were "significant" and 3 (6%) were "nonsignificant." All 15 patients with "significant" variants required specific type of various preservations of the hepatic arterial system. Intraoperative blood loss, transfused blood units, and operation time were greater in patients with "significant" variations than in patients without (P<0.05). Histopathologic diagnosis, tumor staging, morbidity, and mortality did not differ between the 2 groups. The 5-year survival was 33% for patients with "significant" variations and 63% for patients without (P<0.05). CONCLUSIONS: Information on arterial anatomy in the peripancreatic and hepatic areas is necessary for preoperative evaluation in patients requiring radical pancreatoduodenectomy. Presence of "significant" arterial variations may be considered as one of the negative prognostic factors in patients with periampullary cancer.  相似文献   
92.
It is well known that sex steroids play important roles in the development of invasive ductal carcinoma (IDC) of the human breast. However, biological significance of sex steroids remains largely unclear in ductal carcinoma in situ (DCIS), regarded as a precursor lesion of IDC, which is partly due to the fact that the intratumoral concentration of sex steroids has not been examined in DCIS. Therefore, in this study, we first examined the intratumoral concentrations of estradiol and 5alpha-dihydrotestosterone (DHT) using liquid chromatography/electrospray tandem mass spectrometry in DCIS. Intratumoral concentrations of both estradiol and DHT were threefold higher in DCIS than non-neoplastic breast tissues and estrogen-producing enzymes (aromatase, steroid sulfatase, and 17beta-hydroxysteroid dehydrogenase type 1 (17betaHSD1)), and androgen-producing enzymes (17betaHSD5 and 5alpha-reductase type 1 (5alphaRed1)) were abundantly expressed in DCIS by real-time PCR and immunohistochemical analyses. The intratumoral concentration of DHT was significantly lower in IDC than DCIS, while the expression of aromatase mRNA in carcinoma cells and intratumoral stromal cells was significantly higher in IDC than those in DCIS. Immunohistochemistry for sex steroid-producing enzymes in DCIS demonstrated that 5alphaRed1 immunoreactivity was positively correlated with Ki-67 labeling index and histological grade and was also associated with an increased risk of recurrence in patients with DCIS examined. Results of our study suggest that intratumoral concentrations of estradiol and DHT are increased in DCIS, which is possibly due to intratumoral production of these steroids. Therefore, estradiol and DHT may play important roles in the development of DCIS of the human breast.  相似文献   
93.
94.
Background As noninvasive tests for Helicobacter pylori infection, the 13C-urea breath test (UBT) and stool antigen test have been widely used. In children, however, there are few studies reporting which test shows superior performance. The purpose of this study was to compare the 13C-UBT and stool antigen test for their accuracy in diagnosing H. pylori infection in children.Methods A total of 123 Japanese children, ages 2 to 17 years (mean, 12 years) who underwent gastric biopsies for H. pylori infection were studied. The diagnoses included gastritis (n = 55), gastric ulcer (n = 5), duodenal ulcer (n = 20), iron-deficiency anemia (n = 7), and other conditions (n = 36). The cutoff value of the 13C-UBT was defined to be 3.5. The stool antigen test was performed using the HpSA enzyme-linked immunosorbent assay (ELISA) (Premier Platinum HpSA). In 16 patients who received eradication therapy, the 13C-UBT and HpSA were repeated 2 months after treatment.Results Based on biopsy tests, 60 children were infected with H. pylori and 63 children were not. For the 13C-UBT, the sensitivity, specificity, and accuracy were 95.0% (95% confidence interval [CI], 86.1%–99.0%), 98.4% (95% CI, 91.5%–100%), and 96.4% (95% CI, 93.6%–99.9%), respectively. For the HpSA, the sensitivity, specificity, and accuracy were 98.3% (95% CI, 90.8%–100%), 98.4% (95% CI, 91.2%–100%), and 98.3% (95% CI, 96.0%–100%), respectively. There were no significant differences between the performance of these two tests. In the assessment of H. pylori eradication, the results of 13C-UBT and HpSA agreed with those of biopsy tests.Conclusions The 13C-UBT and the HpSA are equally accurate for the diagnosis of active H. pylori infection in Japanese children.Kazuie Iinuma, for the Japanese Pediatric Helicobacter study Group  相似文献   
95.
OBJECTIVES: We conducted a collaborative cohort study to evaluate the predictive power of microvolt T-wave alternans (TWA) in patients with preserved left ventricular ejection fraction (LVEF) after myocardial infarction (MI). BACKGROUND: There is little information available about the prognostic value of risk stratification markers in this population. Although these patients have a relatively good prognosis, identifying high-risk patients is important in clinical practice. METHODS: This study enrolled 1,041 post-MI patients with an LVEF > or =40% (average 55 +/- 10%). Microvolt TWA testing was performed 48 +/- 66 days after acute MI, and 10 other risk variables were also evaluated. The end points were prospectively defined as sudden cardiac death or life-threatening arrhythmic events. RESULTS: During a follow-up of 32 +/- 14 months, 38 patients (3.7%) died of nonarrhythmic causes and were not considered for analysis. Of the 1,003 evaluable patients, 18 (1.8%) reached an end point. Microvolt TWA was positive in 169 patients (17%), negative in 747 (74%), and indeterminate in 87 (9%). A positive microvolt TWA test, nonsustained ventricular tachycardia, and ventricular late potentials were predictors of events, and percutaneous coronary intervention decreased the risk rate. On multivariate analysis, a positive microvolt TWA test was the most significant predictor, with a hazard ratio of 19.7 (p < 0.0001). This marker had the highest sensitivity and negative predictive value for events. CONCLUSIONS: In patients with preserved cardiac function, the incidence of indeterminate results of microvolt TWA is low, and a positive test result is associated with arrhythmic events. Microvolt TWA could be used for risk stratification in this low-risk population.  相似文献   
96.
The distribution of a carbohydrate antigen, the sialyl SSEA-1 (sialyl Lex-i), in human lymphoid cells was investigated by flow cytometry with a specific monoclonal antibody, MoAb FH-6. We concluded that the lymphocytes positive for the sialyl SSEA-1 antigen present in normal peripheral blood (PB) are natural killer (NK) cells since the positive cells had an NK activity toward K562 cells, and most of the sialyl SSEA- 1+ cells were simultaneously positive for Leu-11 (CD-16) and Leu-19. Essentially, no T and B cells, defined by Leu-4 (CD3) and Leu-16 (CD20), were positive for the sialyl SSEA-1 antigen in PB samples taken from healthy donors and patients with disorders unrelated to lymphoid malignancies. Among the malignant lymphoid cells, many sialylated SSEA- 1+ cells were observed in large granular lymphocyte (LGL) leukemia cells and some acute lymphoblastic leukemia (ALL) blasts, but not in CLL cells or malignant lymphoma cells. Sialyl SSEA-1 was also positive in some cultured human lymphoid cell lines. We conclude that expression of the sialyl SSEA-1 antigen is strictly limited to a distinct population of NK cells among the mature lymphocytes in normal PB, but the antigen is present in a wide range of immature lymphoblasts of T- and B-cell lineages as well as the NK-cell lineage. The sialyl SSEA-1 antigen disappears from the surface of immature lymphocytes of T- and B- cell lineages during the course of maturation.  相似文献   
97.
Guo H  Lee JD  Guo M  Lu Y  Tang F  Ueda T 《Acta cardiologica》2005,60(3):259-263
OBJECTIVES: This study sought to clarify the differences of intracellular and extracellular magnesium levels in patients with cardiac syndrome X. METHODS: We evaluated the intracellular and extracellular magnesium status of 22 patients with cardiac syndrome X (group A) and 22 age--and gender--matched disorder-free control subjects (group B). Levels of magnesium were determined in serum, urine, erythrocytes, and the 24-h magnesium retention rate was calculated by a magnesium loading test. RESULTS: Group A showed a higher 24-h magnesium retention rate (49.8 +/- 1.3% vs. 32.6 +/- 7.5%, p < 0.05) and a lower intracellular concentration of magnesium in erythrocytes than group B (3.7 +/- 1.4 vs. 5.6 +/- 1.3 fg/cell, p < 0.05), demonstrating the presence of magnesium deficiency in group A.There were no significant differences in the serum concentration of magnesium between groups A and B (0.87 +/- 0.23 vs. 0.83 +/- 0.15 mmol/l). CONCLUSIONS: This study demonstrated that the intracellular magnesium level decreased in patients with cardiac syndrome X.  相似文献   
98.
We have recently found that soluble form of receptor for advanced glycation end products (sRAGE) levels are positively associated with inflammatory biomarkers and the presence of coronary artery disease (CAD) in type 2 diabetic patients. Since advanced glycation end products (AGEs) up-regulate RAGE expression and endogenous sRAGE could be generated from the cleavage of cell surface RAGE, it is conceivable that sRAGE is positively associated with circulating AGEs levels in diabetes. In this study, we examined whether sRAGE were correlated to circulating levels of AGEs and soluble forms of vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) in patients with type 2 diabetes. Eighty-two Japanese type 2 diabetic patients underwent a complete history and physical examination, determination of blood chemistries, sRAGE, AGEs, sVCAM-1 and sICAM-1. Multiple regression analysis revealed that serum levels of AGEs and sVCAM-1 were independently correlated with sRAGE. This study demonstrated that serum levels of sRAGE were positively associated with circulating AGEs and sVCAM-1 levels in type 2 diabetic patients. Our present observations suggest sRAGE level may be elevated in response to circulating AGEs, thus being a novel marker of vascular injury in patients with type 2 diabetes.  相似文献   
99.
We report an unexpected cause of a febrile patient with huge splenomegaly. A 32-year-old patient with fever and huge splenomegaly was admitted to our hospital. Diagnostic splenectomy revealed that the enlarged spleen adhered strongly to the abdominal organs. Pathologically, the splenic parenchyma showed no malignant cells, and the soft tissue adjacent to the splenic hilum showed a proliferation of fibroblastic or myofibroblastic spindle cells with fibrosis and lymphoplasmacytic infiltration. These findings lead to a diagnosis of peritoneal fibrosis, and an administration of 50 mg/day of prednisolone alleviated all the symptoms. The differential diagnosis of huge splenomegaly with fever usually includes hematolymphoid malignancies and infectious diseases; however, our case was diagnosed as idiopathic retroperitoneal fibrosis. Our case suggests that when we see patients with fever and huge splenomegaly, differential diagnosis should include retroperitoneal fibrosis.  相似文献   
100.
Medullary cystic kidney disease (MCKD) is a progressive tubulointerstitial nephropathy, and it leads to end‐stage kidney disease (ESKD). It is an autosomal dominant inherited disease, and is categorized into two types according to the localizing chromosome and timing of ESKD onset. Its pathogenesis has not been revealed clearly, thus accumulation of the cases is very valuable. We report here the first reported case of MCKD with kidney enlargement complicated by IgA nephropathy. A 70‐year‐old male was admitted to our hospital because of renal dysfunction and bilateral kidney enlargement. He was diagnosed as having MCKD complicated by IgA nephropathy (IgA‐N) by renal biopsy. We speculated that he had MCKD type 1 on the basis of the late onset of renal failure and no significant evidence of mutation in the UMOD gene that is associated with MCKD type 2. Thereafter, his kidney function decreased progressively and he started to receive hemodialysis. This is an interesting case of MCKD1 in terms of its sporadic nature, kidney enlargement, and complication of IgA‐N.  相似文献   
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