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21.
Recently, there is increasing evidence suggesting that oxidative sperm DNA damage is closely associated with impaired sperm function and male infertility. 8-Hydroxydeoxyguanosine (8-OHdG) is considered to be a precise and sensitive biomarker of oxidative DNA damage. The present study was thus designed to evaluate the extent of oxidative DNA damage in sperm and its association with male infertility by assaying the 8-OHdG levels in human sperm samples. A total of 114 subjects (60 infertile patients and 54 age-matched healthy workers) participated in this study. The level of 8-OHdG in sperm DNA was determined by high-performance liquid chromatography with electrochemical detection, and the conventional seminal parameters were also measured according to World Health Organization guidelines. It was found that the level of sperm 8-OHdG in infertile patients was significantly higher than that in healthy subjects (10.03 vs. 4.79 8-OHdG/10(5) dG; geometric mean, P < 0.001). The correlation between sperm 8-OHdG levels and conventional seminal parameters were also analyzed. There is a significant positive correlation between 8-OHdG and sperm head defects (r = 0.38, P < 0.001), whereas significant inverse correlations were noted for 8-OHdG with sperm density (r = -0.42, P < 0.001), total sperm number (r = -0.42, P < 0.001), sperm motility (r = -0.24, P < 0.01), and normal sperm morphology (r = -0.39, P < 0.001). Data from this study thus indicate that oxidative damage to sperm DNA may be important in the etiology of male infertility and that the assay of sperm 8-OHdG may have potential diagnostic value in the evaluation of sperm function and male fertility.  相似文献   
22.
BACKGROUND AND METHOD: Oculokinetic perimetry (OKP) was performed on 98 patients (187 eyes) using the Damato 26-point glaucoma screening chart. Results were compared with those obtained from a 24-2 full threshold test on a Humphrey Field Analyser (HFA). RESULTS: In its ability to detect pathology in individual eyes, OKP had a sensitivity of 75.0% and a specificity of 71.4%. To detect glaucoma, OKP demonstrated a sensitivity of 86.0% and a specificity of 56.1%. The number of OKP defects detected increased with increasing HFA mean defect and corrected pattern standard deviation. Whereas moderate and severe field defects were almost always detected, smaller and shallower glaucoma defects were often missed. CONCLUSION: The fall in sensitivity and specificity of the OKP chart in identifying milder glaucomatous field defects diminishes its value as a screening test. However, its introduction into wider use in the community may increase awareness of glaucoma amongst general practitioners and members of the public, and help to detect previously undiagnosed glaucoma with moderate to severe damage. A normal OKP finding does not exclude the presence of early glaucoma. Combined with ophthalmoscopy, OKP may improve glaucoma detection rates amongst non-ophthalmologists.  相似文献   
23.
Marrow regeneration after mechanical depletion   总被引:1,自引:0,他引:1  
Brecher  G; Tjio  JH; Smith  WW; Haley  JE 《Blood》1976,48(5):679-686
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration.  相似文献   
24.
PURPOSE: To discuss the absolute benefits from adjuvant systemic therapy knowledge of long-term outcomes and baseline risks of relapse and disease-specific survival are required. We assessed the 10-year outcomes in a population-based cohort of node-negative (N-) lymphovascular negative (LV-) early breast cancers diagnosed from 1989 to 1991 who did not receive adjuvant systemic therapy. METHODS: One thousand one hundred eighty-seven cases of pT(1-2)N(0) LV- breast cancers with a median follow-up of 10.4 years were reviewed. Kaplan-Meier survival curves for relapse free survival (RFS), breast cancer-specific survival (BCSS) and overall survival (OS) were compared with log-rank tests with cohorts stratified for tumor size and grade. RESULTS: The median age of this series was 62 years. Four hundred thirty tumors were < or = 1 cm in diameter (cohort 1), 507 were 1.1-2 cm (cohort 2), and 250 were 2.1 to 5 cm in diameter (cohort 3). The 10-year outcomes for cohorts 1, 2, and 3, respectively, were significantly different: RFS, 82%, 75%, and 66%; BCSS, 92%, 90%, and 77%; and OS, 79%, 78%, and 66%. Tumor grade significantly altered outcome within size cohorts, particularly in pT(1)N(0) breast cancers. CONCLUSION: This study provides detailed information on the continued relapse and breast cancer death rate to 10 years of follow-up. Specifically, without adjuvant systemic therapy, patients with LV-, N - breast cancer had a > or = 25% 10-year risk of relapse and a corresponding 10-year breast cancer death rate of > or = 10% if they had either a grade 3 tumor < or = 1 cm, a grade 2 to 3 tumor from 1.1 to 2 cm, or any grade tumor greater than 2 cm.  相似文献   
25.
Tumor samples are available from over 19,600 Stage I-III breast cancer patients treated according to evolving British Columbia guidelines from 1978 to 1990. A tissue mico-array (TMA) was constructed from 930 of these patients, all of whom participated in randomized or phase II studies. Outcome was defined as 20-year Breast Cancer specific Survival (BrCaSS), with events defined as Breast Ca death. Follow up was median 17.8 years (ranges 11–28). Multiple tumor markers were tested, and results correlated with 20-year BrCaSS for markers expressed versus non-expressed. No difference in BrCaSS was found for aromatase, integrin-linked kinase (ILK), IGF-1 and Topo-isomerase-2. The negative predictive value of IHC versus FISH and ACIS-IHC versus FISH was 96 and 97%, respectively. The positive predictive value of IHC versus FISH and ACIS-IHC versus FISH was 84 and 84%, respectively. All tests, with the exception of HER-2 FISH were done by IHC. Results of other markers (VEGF, ER/PgR, hypoxia markers, etc.), and an interactive multivariate analysis adjusting for conventional prognostic factors and for all above markers, are in progress. Conclusions 1. The TMA is a technique which provides opportunity for rapid screening of multiple genetic markers.2. Expression of Her-2/Neu, uPA, Cox-2 and Cytokeratin 17/5,6 (but not of Aromatase, ILK, TOPO-II and IGF-1) is associated with inferior BrCaSS.3. HER-2 determination by ACIS-IHC provides comparable results to IHC done manually (with a potential for more uniform reporting), and both provide comparable results to Her-2 assessment by FISH. ** ACIS-IHC:IHC red by Automated Cell Image System (M.L.)  相似文献   
26.
A 15 year old boy with autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy syndrome suffered recurrent episodes of severe intractable diarrhoea, steatorrhoea, and hypocalcaemia. The only treatment modality, which controlled the malabsorption syndrome, was immunosuppression with intravenous high dose methylprednisolone and oral methotrexate maintenance therapy.  相似文献   
27.
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994) and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the striking similarity in lifestyle risk factors for colorectal cancer and insulin resistance, proposed that the hyperinsulinemia, glycemia and hypertriglyceridemia associated with insulin resistance promotes colon cancer. To compare the effect of diet on colon cancer promotion and insulin resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids and energy in pairwise comparisons on average size of aberrant crypt foci (ACF) and on glucose intolerance in the same animals in a single experiment. Diets high in fat and energy increased and diets with increased n-3 fatty acids and calorie restriction decreased both ACF growth and glucose intolerance compared with control diets. The measures of promotion of colon cancer and insulin resistance were strongly correlated (n = 98, r = 0.67, P < 0.001). In addition, both were highly correlated with daily energy intake (r = 0.62 and 0.66) and were also correlated with basal (post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P < 0.01). We concluded that ACF growth and glucose intolerance are correlated for a wide range of diets and that increased circulating energy (glucose and triglycerides) may lead to both colon cancer promotion and insulin resistance.   相似文献   
28.
A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
29.
The vast majority of new cases of colorectal cancer, the second most common cause of death in men and women in the United States, are attributable to environmental rather than genetic causes. Recent research has clarified inconsistencies in the literature and has explored new pathways through which risk factors may act. This review discusses newly published, selected interesting and important findings in colorectal cancer etiology; these include postmenopausal hormone use, nonsteroidal anti-inflammatory drug use, obesity, physical activity, diet, and other confirmed epidemiologic associations. This research provides insight into mechanisms and offers opportunities for prevention.  相似文献   
30.
Leukemia is one of the major diseases causing cancer‐related deaths in the young population, and its cure rate is unsatisfying with side effects on patients. Fluorouracil (5‐FU) is currently used as an anticancer drug for leukemia patients. Casticin, a natural polymethoxyflavone, exerts anticancer activity against many human cancer cell lines in vitro, but no other reports show 5‐FU combined with casticin increased the mouse leukemia cell apoptosis in vitro. Herein, the antileukemia activity of 5‐FU combined with casticin in WEHI‐3 mouse leukemia cells was investigated in vitro. Treatment of two‐drug combination had a higher decrease in cell viability and a higher increase in apoptotic cell death, the level of DNA condensation, and the length of comet tail than that of 5‐FU or casticin treatment alone in WEHI‐3 cells. In addition, the two‐drug combination has a greater production rate of reactive oxygen species but a lower level of Ca2+ release and mitochondrial membrane potential (ΔΨm) than that of 5‐FU alone. Combined drugs also induced higher caspase‐3 and caspase‐8 activities than that of casticin alone and higher caspase‐9 activity than that of 5‐FU or casticin alone at 48 hours treatment. Furthermore, 5‐FU combined with casticin has a higher expression of Cu/Zn superoxide dismutase (SOD [Cu/Zn]) and lower catalase than that of 5‐FU or casticin treatment alone. The combined treatment has higher levels of Bax, Endo G, and cytochrome C of proapoptotic proteins than that of casticin alone and induced lower levels of B‐cell lymphoma 2 (BCL‐2) and BCL‐X of antiapoptotic proteins than that of 5‐FU or casticin only. Furthermore, the combined treatment had a higher expression of cleaved poly (ADP‐ribose) polymerase (PARP) than that of casticin only. Based on these findings, we may suggest that 5‐FU combined with casticin treatment increased apoptotic cell death in WEHI‐3 mouse leukemia cells that may undergo mitochondria and caspases signaling pathways in vitro.  相似文献   
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