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101.
OBJECTIVES: Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) has become established in the diagnosis of pancreatic cancer. The combination of pathological diagnosis and analysis for mutant K-ras gene was investigated to improve the accuracy of diagnosis. METHODS: EUS-FNA was performed in 34 patients with pancreatic masses (26 adenocarcinomas and eight chronic pancreatitis). Mutant ras gene was analyzed semiquantitatively in the specimens obtained by EUS-FNA as well as in pancreatic juice obtained by ERCP. RESULTS: Mutant gene was detected at high amounts (more than 2% of total ras genes) in 20 of 26 (77%) specimens of EUS-FNA and in 12 of 19 (63%) of pancreatic juice in cases with pancreatic carcinoma. Cytological diagnosis of malignancy by EUS-FNA was found in 16 of 26 (62%) patients with pancreatic cancer. Accurate diagnosis of the carcinoma was 21 of 26 (81%) by combined cytology and molecular method of EUS-FNA, and increased to 23 of 26 (88%) by adding molecular analysis of pancreatic juice. In contrast, mutant gene was absent or low level despite suspicious cytology in patients with benign pancreatic lesion. CONCLUSION: Quantitative analysis of mutant ras gene supplemented conventional cytology of EUS-FNA and ERCP. Detection of mutation at high amounts may represent pancreatic cancer, whereas its absence increased the possibility of benign lesion.  相似文献   
102.
OBJECTIVE: The purpose of this study is to investigate the distribution of Mycobacterium tuberculosis genotypes, such as Beijing family and other genotypes in Okayama district, and to examine the relation between these genotype strains and prevalent strains. METHODS: The 142 M. tuberculosis strains isolated in Okayama City from January 2000 to December 2002 were subjected to IS6110-RFLP and spoligotyping for the population-based study. In addition, 13 strains having 1 to 5 IS6110 copies isolated in Okayama Prefecture excluding Okayama City were also subjected to spoligotyping. RESULTS: A total of 103 (72.5%) of 142 strains belonged to Beijing family. Furthermore, 3 of 4 groups of prevalent strains belonged to the family. Twenty one strains out of 39 rest strains could be classified into 10 shared types (STs) of 259 STs in the worldwide spoligotype database. In addition, 15 out of 26 strains from inside and outside of Okayama City having 1 to 5 IS6110 copies showed common unique spoligotype. Moreover, the age of majority patients who were infected with M. tuberculosis of the Beijing family or other genotypes were older than 60 years. CONCLUSION: It was suggested that Beijing family had been the main infection source, and the spread of strains of Beijing family and other genotypes occurred considerably in old times, and the unique genotype strains remained for a long time as peculiar strains.  相似文献   
103.
Seven anopheline species from Costa Marques, Rondonia, Brazil were compared with Anopheles darlingi for susceptibility to infection by Plasmodium vivax. Laboratory-reared F1 progeny of field-collected An. darlingi and the test anopheline species were fed at the same time on the same patients, all of whom had gametocytes in peripheral blood before treatment. Mosquitoes were dissected on day 8 after infection for oocysts and on days 14-16 after infection for sporozoites. The mean numbers of P. vivax oocysts and the percent of salivary gland infections for An. darlingi and An. deaneorum were similar and far exceeded those found in the other anopheline species tested. Anopheles albitarsis and An. mediopunctatus were less susceptible to infection by oocyst measurements than An. darlingi. However, for oocyst-infected An. albitarsis and An. mediopunctatus, the percent of mosquitoes with salivary gland infections and the numbers of sporozoites in the salivary glands were similar to An. darlingi. Anopheles triannulatus and An. oswaldoi were both susceptible to P. vivax infection, but the sporozoite infection rates and the numbers of sporozoites observed in the salivary glands were very low. Anopheles braziliensis and An. benarrochi both developed oocysts, but were never observed to have sporozoites in the salivary glands. These studies implicate some anopheline species as potential malaria vectors, but also show that species previously incriminated by ELISA techniques are not vectors of malaria parasites in Costa Marques, Rondonia, Brazil.  相似文献   
104.
A patient underwent radiofrequency (RF) catheter ablation for a drug-refractory ventricular tachycardia, but RF energy application at an endocardial site of the left ventricular outflow tract and at the left sinus of Valsalva could not eliminate the tachycardia. The earliest ventricular activation during the arrhythmia, which preceded the onset of the QRS complex by 32 ms, was found within the great cardiac vein and complete elimination of the tachycardia was finally achieved with RF application at that site.  相似文献   
105.
Background We examined the current status and diagnostic accuracy of currently available techniques for tumor staging and assessed treatment outcomes in patients with superficial esophageal cancer who received esophaguspreserving therapy, such as endoscopic mucosal resection (EMR) alone or combined with chemoradiotherapy (CRT). Methods In 274 patients with superficial esophageal cancer, we examined the depth of tumor invasion and the degree of lymph node metastasis by means of endoscopy, magnifying endoscopy, endoscopic ultrasonography (EUS), computed tomography (CT), and cervical and abdominal ultrasonography (US). We compared treatment outcomes among treatment groups according to the depth of tumor invasion. Results The rates of correctly diagnosing the depth of tumor invasion were 89.6% on conventional endoscopy, 90.1% on magnifying endoscopy, and 85% on scanning with a high-frequency miniature ultrasonic probe (miniature US probe). Diagnostic accuracy for the m3 or sm1 cancers was poor. Magnifying endoscopy allowed invasion to be more precisely estimated, thereby improving diagnostic accuracy. However, lesions that maintained their surface structure despite deep invasion were misdiagnosed on magnifying endoscopy. A miniature US probe was useful for the assessment of such lesions. The diagnostic accuracy of EUS for lymph node metastasis was 83%, with a sensitivity of 76%. The sensitivity of CT was 29%, and that of cervical and abdominal US was 17%. Patients with m1 or m2 cancer had good outcomes after esophagus-preserving therapy. Although there were no significant differences in survival rates, many patients with sm2 or sm3 cancer who received CRT died of their disease. Nodal recurrence was diagnosed by EUS. In patients who received CRT, the time to the detection of recurrence was slightly prolonged. Conclusions Long-term follow-up at regular intervals is essential in patients with m3 or sm esophageal cancers who receive esophagus-preserving treatment. At present, EUS is the most reliable technique for the diagnosis of lymph node metastasis and is therefore essential for pretreatment evaluation as well as for follow-up. Earlier detection of recurrence at a level that would potentially salvage treatment remains a topic for future research. Review articles on this topic also appeared in the previous issue (Volume 4 Number 3). An editorial related to this article is available at .  相似文献   
106.
The objectives of this study were to evaluate dosimetric quality and acute toxicity of volumetric-modulated arc therapy (VMAT) and daily image guidance in high-risk prostate cancer patients. A total of 100 consecutive high-risk prostate cancer patients treated with definitive VMAT with prophylactic whole-pelvic radiotherapy (WPRT) were enrolled. All patients were treated with a double-arc VMAT plan delivering 52 Gy to the prostate planning target volume (PTV), while simultaneously delivering 46.8 Gy to the pelvic nodal PTV in 26 fractions, followed by a single-arc VMAT plan delivering 26 Gy to the prostate PTV in 13 fractions. Image-guided RT was performed with daily cone-beam computed tomography. Dose–volume parameters for the PTV and the organs at risk (OARs), total number of monitor units (MUs) and treatment time were evaluated. Acute toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. All dosimetric parameters met the present plan acceptance criteria. Mean MU and treatment time were 471 and 146 s for double-arc VMAT, respectively, and were 520 and 76 s for single-arc VMAT, respectively. No Grade 3 or higher acute toxicity was reported. Acute Grade 2 proctitis, diarrhea, and genitourinary toxicity occurred in 12 patients (12%), 6 patients (6%) and 13 patients (13%), respectively. The present study demonstrated that VMAT for WPRT in prostate cancer results in favorable PTV coverage and OAR sparing with short treatment time and an acceptable rate of acute toxicity. These findings support the use of VMAT for delivering WPRT to high-risk prostate cancer patients.  相似文献   
107.
AimsTime in range (TIR), an index of glycemic control and also blood glucose fluctuation, obtained from continuous glucose monitoring (CGM), has been increasing its importance along with the spread of CGM in recent years. For a while, glycated albumin (GA) has been also used as a glycemic control index during about 2-weeks in routine clinical practice. It has not yet been confirmed under optimal condition whether TIR and GA correlates. Clarification of the correlation between TIR and GA, which was measured immediately after 2-weeks of CGM, might be a finding that further supports the utility of TIR.MethodsGA was measured at the conclusion of 2-week CGM in 71 diabetes outpatients at our hospital, and the correlation between GA and indices such as TIR obtained from CGM was statistically analyzed.ResultsIt was found that TIR and time above range (TAR) were significantly correlated with GA. Upon performing multiple regression analysis, TIR, TAR and BMI. indicated a significant regression coefficient with respect to GA.ConclusionsThese findings further support the utility of TIR as a marker of glycemic control that it might also be correlated with GA, and also suggest a relation between GA and blood glucose fluctuation.  相似文献   
108.
The role of endothelium-derived nitric oxide (NO) in the metabolic control of coronary blood flow (CBF) in heart failure (HF) is poorly understood, so the present study investigated the effects of inhibitors of NO synthesis on the response of CBF to changes in myocardial oxygen consumption (MVO2) in dogs with HF produced by rapid ventricular pacing and in control dogs. The CBF, MVO2, and other hemodynamic parameters were measured in anesthetized animals. Before infusion of Nomega-nitro-L-arginine methyl ester (L-NAME), the increases in CBF and MVO2 during pacing tachycardia were not significantly different between the control and HF dogs. Intracoronary infusion of L-NAME did not alter the responses of CBF or MVO2 to pacing tachycardia in the control dogs, but in the HF dogs, it reduced the CBF response to pacing tachycardia without altering the tachycardia-induced changes in MVO2. Intracoronary infusion of L-arginine reversed the effect of L-NAME. These results suggest that in HF dogs NO contributes to the regulation of CBF in response to an increased metabolic demand.  相似文献   
109.
CD13/aminopeptidase N (E.C.3.4.11.2) is an ectoenzyme located in the outer membrane of a variety of cells. Because aminopeptidase expression was shown to be upregulated by a Th1-related cytokine, IFN-gamma, we examined here the significance of CD13/aminopeptidase N in pulmonary sarcoidosis. The activity of aminopeptidase in bronchoalveolar lavage fluid (BALF) was significantly higher in patients with sarcoidosis than in normal volunteers (NV) and control patients (CP). The activity significantly correlated with lymphocyte percentages and the ratio of CD4+ to CD8+ T lymphocytes in the BALF, and was higher in patients with sarcoidosis with parenchymal involvement than in those without the involvement. CD13/aminopeptidase N protein, which has a molecular mass of approximately 150 kD, was detectable in alveolar macrophages (AM) from patients with sarcoidosis at higher levels than in those from NV. CD13/aminopeptidase N induced in vitro chemotactic migration of human lymphocytes in a concentration range of 10(-)(5) to 10(-)(1) U/ml. The chemotactic activity was greater for CD4+ T lymphocytes than for CD8+ T lymphocytes. The enzymatic activity of CD13/aminopeptidase N was responsible for the chemotactic activity because bestatin, an inhibitor of CD13/aminopeptidase N, abolished the chemotactic activity. Higher chemotactic activity for lymphocytes was detected in the BALF from patients with sarcoidosis than in that from NV, and the activity was significantly decreased by treatment with bestatin. This study indicates that CD13/ aminopeptidase N expressed in AM may have a role in T-lymphocyte involvement in the sarcoid lung and the pathogenesis of alveolitis in this disorder.  相似文献   
110.
Autoimmune diseases, especially autoimmune thyroid disease, frequently develop after delivery due to the immune rebound mechanism. Most cases have transient dysfunction of affected organs. Cardiac dysfunction developed after delivery is called postpartum or peripartum cardiomyopathy. However, the aetiology of the disease is not clarified yet. Here we report three cases that developed acute heart failure in the postpartum period. One was complicated with an atrioventricular block and postpartum autoimmune thyroiditis. All patients recovered to normal cardiac function or pre-attack condition after 1 month of therapy with conventional drugs and bed rest. All three had positive antiheart antibody detected by indirect immunofluorescence assay, and one had antibody to heart myosin detected by enzyme-linked immunosorbent assay. Moreover, one of two patients examined revealed lymphocytic infiltration by endomyocardial biopsy. Antibodies to 26 viruses were not elevated significantly during the first 2 weeks after admission in any case. It is strongly suggested that heart failure is induced by postpartum autoimmune myocarditis, and thus clinicians should be aware of this disease.  相似文献   
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