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991.
OBJECTIVES: Therapeutic results in advanced chronic lymphocytic leukemia (CLL) are still unsatisfactory in terms of complete remission achievement and duration, in spite of the extensive use of purine analogs. The objective of this study was to describe the clinical characteristics and treatment results from a series of 32 patients managed with a therapeutic program based on the combination of fludarabine and cyclophosphamide (CTX). METHODS: Thirty-two patients (median age 63 yr, range 42-75 yr) with newly diagnosed (47%) or refractory-relapsed (53%) CLL were programmed to receive six courses of a 3-d combination of fludarabine at 30 mg/m2/d plus CTX at 300 mg/m2/d. Refractory-relapsed patients had previously received different chemotherapy lines from 1 to 5. RESULTS: Fourteen of 32 (44%) patients achieved a complete remission, 16 (50%) obtained partial remission and two (6%) failed to respond. The CR rate was higher in untreated patients; in particular, CR was achieved in nine of 15 (60%) newly diagnosed cases as opposed to five of 17 (29%) among pretreated patients. Toxicity was caused by myelosuppression and/or infections in most cases. After a median follow-up of 24 months (range 8-48 months), 20 of 32 patients (62%) are alive, and 14 of 32 (44%) are free from progression. Median overall survival and median time to progression were 35 and 25 months, respectively. CONCLUSION: The combination of fludarabine with CTX is effective in advanced CLL with acceptable toxicity, either as first-line therapy or in refractory-relapsed patients. In particular, a considerable rate of complete remission can be achieved in untreated patients. Myelosuppression represents the major side-effect.  相似文献   
992.
ONYX-015 is a genetically modified adenovirus with a deletion of the E1B early gene and therefore is designed to replicate preferentially in p53-mutated cells causing their death. We previously demonstrated that the ONYX-015 virus kills anaplastic thyroid carcinoma (ATC) cells and enhances the antineoplastic effects of doxorubicin and paclitaxel. Here we report that ONYX-015 increased the cytopathic effect of radiotherapy in three ATC cell lines. In fact, ONYX-015 and radiation induced a significant cytopathic effect on ATC cells. DNA fragmentation analysis showed that ATC ONYX-015-treated cells were very sensitive to radiation-induced apoptosis. In addition, low doses of ONYX-015 associated with a single radiation dose of 10 Gy delayed the growth of a xenograft tumor induced by ARO cells in athymic mice. Our results suggest that the combination of ONYX-015 and radiotherapy should be considered for experimental trials in patients with anaplastic thyroid carcinoma.  相似文献   
993.
The DBL transforming gene was originally identified by transfection of NIH 3T3 cells with DNA from a human B-cell lymphoma. This gene was found to have arisen as a result of recombination of the 3' portion of the DBL protooncogene coding sequences with an unrelated segment of human DNA. It encodes a cytoplasmic protein that is equally distributed between cytosol and crude membrane fractions. To further characterize this transforming gene, a biologically active cDNA clone of the DBL transforming gene mRNA was isolated. Analysis of the sequence of the DBL oncogene cDNA revealed a long open reading frame that encodes a hybrid protein whose first 50 amino acids (at least) derive from a complete exon of a different locus. No significant homology with known oncogenes or any known protein sequences was demonstrated. The computer analysis of the predicted DBL protein indicated it is highly hydrophilic with no hydrophobic domains characteristic of a membrane-spanning region or signal peptide. Thus, the DBL oncoprotein is distinct among known transforming gene products.  相似文献   
994.
OBJECTIVES: To evaluate whether chronic therapy with probiotics affects plasma levels of cytokines and oxidative/nitrosative stress parameters, as well as liver damage, in patients with various types of chronic liver disease. PATIENTS AND METHODS: A total of 22 nonalcoholic fatty liver disease (NAFLD) and 20 alcoholic liver cirrhosis (AC) patients were enrolled in the study and compared with 36 HCV-positive patients with chronic hepatitis without (20, CH) or with (16, CC) liver cirrhosis. All patients were treated with the probiotic VSL#3. Routine liver tests, plasma levels of tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-6 and -10, malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE), S-nitrosothiols (S-NO), were evaluated on days -30, 0, 90, and 120. RESULTS: Treatment with VSL#3 exerted different effects in the various groups of patients: in NAFLD and AC groups, it significantly improved plasma levels of MDA and 4-HNE, whereas cytokines (TNF-alpha, IL-6, and IL-10) improved only in AC patients. No such effects were observed in HCV patients. Routine liver damage tests and plasma S-NO levels were improved at the end of treatment in all groups. CONCLUSIONS: Results of the study suggest that manipulation of intestinal flora should be taken into consideration as possible adjunctive therapy in some types of chronic liver disease.  相似文献   
995.
The abuse of alcohol is associated with chronic cardiomyopathy, hypertension, and arrhythmia. Abstinence or using alcohol in moderation can reverse these cardiovascular problems. Alcohol is also distinguished among the substances of abuse by having possible protective effects against coronary artery disease and stroke when used in moderate amounts. Amphetamines (eg, speed, ice, ecstasy) have many of the cardiovascular toxicities seen with cocaine, including acute and chronic cardiovascular diseases. Heroin and other opiates can cause arrhythmias and noncardiac pulmonary edema, and may reduce cardiac output. Cardiovascular problems are less common with cannabis (marijuana) than with opiates, but major cognitive disorders may be seen with its chronic use. It is still controversial whether caffeine can cause hypertension and coronary artery disease, and questions have been raised about its safety in patients with heart failure and arrhythmia.  相似文献   
996.
BACKGROUND: Alterations in epithelial proliferation and apoptosis in colonic mucosa are associated with an increased risk of colon cancer. It is unclear if these alterations represent a generalised "field defect". AIMS: To analyse segmental patterns of cell proliferation and apoptosis in the colon of subjects with a high and no apparent risk of colon cancer. METHODS: Pancolonoscopy was performed in 15 patients with resected adenomas (> or =1.5 cm) and in nine subjects without an apparent risk of colorectal cancer. Mucosal biopsies were taken from the right colon, left colon, and sigmoid rectum. Crypt cell proliferation and apoptosis were evaluated, respectively, with bromodeoxyuridine immunohistochemistry and terminal deoxyuridine nucleotidyl nick end labelling of DNA strand breaks. Results are expressed as total labelling index (TLI) and labelling index (LI) for each of the five compartments in which colonic crypts were divided (fourth and fifth compartments were evaluated together) for cell proliferation and as apoptotic index (AI) for apoptosis assessment. RESULTS: No significant segmental variations in proliferation were found in either group. Compared with controls, adenoma patients had higher TLIs for the right (p>0.05), left (p<0.005), and sigmoid rectum (p<0.05) segments, and higher left colon LIs for crypt compartments (compartment 1, p<0.01; compartment 2, p<0.005; compartment 3, p<0.001; compartments 4-5, p<0.01). Control AIs were similar in all segments but in the adenoma patients left colon and sigmoid rectum AIs were lower than their right colon indexes (p<0.05, p<0.05) and corresponding values for controls (p<0.01, p<0.05). CONCLUSIONS: The colonic mucosa of patients with past adenomas presents diffuse hyperproliferation and, distally, abnormally distributed proliferating cells and markedly reduced apoptosis. These changes represent a significant risk for malignancies and could account for the high prevalence of left colon tumours.  相似文献   
997.
A 42-year-old woman presented with acute bullous skin lesions and angio-oedema that had developed 3 months after initiation of treatment with carbamazepine for epilepsy. Chromatographic analysis of urinary porphyrins was compatible with variegate porphyria. This was manifested initially by neurological symptoms that were mistaken for epilepsy and later by cutaneous symptoms also. Histological findings excluded hepatic porphyria, but revealed severe fatty changes thought to be caused by idiosyncratic metabolism of carbamazepine. While the porphyrinogenicity of carbamazepine is well known, the presence of variegate porphyria has not been reported. The toxic hepatic effects of the drug on hepatic cytochrome P-450, which is involved in haem metabolism, could have aggravated the pre-existent porphyria, provoking the onset of skin lesions.  相似文献   
998.
OBJECTIVE: To investigate whether the serological markers of autoimmunity and the clinical features of autoimmune disease which occur in hepatitis C virus (HCV)-infected subjects are correlated to each other and/or to the clinical pattern of the disease. METHODS: Seventeen symptom-free, anti-HCV antibody positive subjects, 17 patients with chronic hepatitis C, 21 patients with mixed cryoglobulinemia (MC), and as controls 17 anti-HCV negative patients with dyspepsia were enrolled in a prospective study. A patient history, clinical examination, self-administered questionnaire and laboratory investigations (hepatic enzyme levels, serum HCV-RNA and anti-HCV antibody testing, and serum autoantibody profile) were performed to detect liver and/or autoimmune disease. RESULTS: Serological markers of autoimmunity and clinical findings of autoimmune disease were found to be more frequent in the HCV-infected patients considered as a whole than in controls. However, rheumatoid factor and clinical findings of autoimmune disease were more frequent in MC patients, while anti-smooth muscle antibodies not linked to symptoms or signs of autoimmune disease were detected in all groups of HCV-infected individuals, including healthy carriers and subjects who had recovered from a previous HCV infection. CONCLUSION: Anti-smooth muscle antibodies, a serological marker of autoimmunity, are detectable in HCV-infected subjects whatever their clinical status. Clinical findings of autoimmune disease prevalently occur in patients with mixed cryoglobulinemia.  相似文献   
999.
OBJECTIVES: Abdominal ultrasound can assess the extent and localization of Crohn's disease, and an increased bowel wall thickness is the most common finding. Our aim was to correlate bowel wall thickness at ultrasound, with the risk of short-term surgical outcome in patients with Crohn's disease. MATERIALS AND METHODS: From 1997 to 2000 we performed ultrasound in 174 consecutive patients with Crohn's disease. Surgical operations were recorded over a 1-yr follow-up. Logistic regression analysis was performed to identify clinical and ultrasound risk factors for surgery. RESULTS: Fifty-two patients underwent surgery within 1 yr. Indication for surgery was strictures in most of the cases. Median bowel wall thickness was higher in patients with surgery (8 mm) than those without surgery (6 mm) (p < 0.0001). A receiver operating characteristic (ROC) curve was constructed taking into account bowel wall thickness for selecting patients with a high risk of surgery. The optimized cut-off for equally important sensitivity and specificity was calculated at 7.008 mm. The binary regression analysis showed that CDAI > 150, absence of previous surgery, stricturing-penetrating pattern, the presence of intestinal complications, and intestinal wall thickness >7 mm were associated with an increased risk of surgery. Patients with intestinal wall thickness >7 mm at ultrasound had the highest risk (OR: 19.521, 95% CI: 5.362-71.065). CONCLUSIONS: Data suggest that bowel wall thickness >7 mm at ultrasound is a risk factor for intestinal resection over a short period of time. Routine use of abdominal ultrasound during evaluation of patients with Crohn's disease may identify a subgroup that is at high risk for surgery. (Am J Gastroenterol 2004;99:1-7)  相似文献   
1000.
Staging and monitoring of multiple myeloma (MM) is mainly based on monoclonal component quantification; the absence of such a parameter renders difficult follow up of patients with nonsecretory MM (nsMM). In this study our aims were to determine the specificity and sensitivity of Tc99m-sestaMIBI scintigraphy at diagnosis and during follow up of nsMM patients. Nine nsMM patients were prospectively studied at diagnosis and during treatment for a mean time of 33 months (range: 12-65+). Tc99m-sestaMIBI (MIBI) scintigraphy was compared to conventional imaging (CI: X ray with CAT or NMR details) at diagnosis and during follow up. At diagnosis, CI and MIBI were concordant in three patients; CI showed more focal lesions than MIBI in four patients, while MIBI revealed more focal lesions than CI in two patients. During the follow up, MIBI uptake was normal in the four patients who achieved remission. Five patients did not achieve remission: CI and MIBI were concordant in three, while MIBI was falsely negative in two patients. In conclusion, Tc99m-sestaMIBI scintigraphy has high sensitivity (no false positive cases) and 78% specificity (2/9 false negative cases) in tracing active nsMM lesions; it should be considered complementary to CI for monitoring this rare disease.  相似文献   
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