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101.
102.
BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset.  相似文献   
103.
OBJECTIVES: This study was performed to evaluate the clinical and serial angiographic outcomes of patients undergoing sirolimus-eluting stent (SES) implantation for unprotected left main coronary artery (LMCA) stenosis. BACKGROUND: The efficacy of SES has led to their expanded use for off-label indications, including LMCA disease. METHODS: Unprotected LMCA intervention with SES was attempted in 50 patients. Surveillance angiography was performed at three and nine months' follow-up. RESULTS: The target lesion involved the distal LMCA in 47 patients (94%). In-lesion restenosis occurred in 21 patients (42%), was focal in 85% of cases, and in 82% involved the branch ostia, sparing the LMCA itself. Target lesion revascularization (TLR) occurred in 19 patients (38%) over a mean follow-up of 276 +/- 57 days; TLR was ischemia-driven in 7 patients (14%). Late loss was significantly greater within the left circumflex (LCX) ostium compared to the parent vessel (PV) of the LMCA bifurcation (0.83 +/- 0.89 mm vs. 0.49 +/- 0.72 mm, p = 0.04). Late loss continued to increase between three- and nine-month follow-up. Final minimal luminal diameter and maximal balloon pressure were independent predictors of restenosis of the PV. CONCLUSIONS: Restenosis is a frequent finding when serial angiographic follow-up is performed after SES implantation for unprotected distal LMCA lesions. Restenosis is usually focal, most often involves the LCX ostium, and often occurs without symptoms.  相似文献   
104.
OBJECTIVE: To Determine the incidence of constipation in Albacete province and its relation with diet and lifestyle. PATIENTS AND METHODS: Cross-sectional population survey. We studied 414 participants over 50 years of age in Albacete province. 445 persons over 50 years of age were included in the study. All participants were selected by systematic random sampling; 414 participants filled in the questionnaire correctly. Main measures: age, weight and height, marital status, level of education and occupation; presence of a disease, number of sleep hours a day, physical exercise, smoking, alcohol intake, drug intake (anti-inflammatories and laxatives); bowel habit, diet, meal frequency and place; food intake frequency per week, daily intake of water, coffee, tea and herbal beverages; vitamin and fiber supplements; presence of cancer in the family. RESULTS: 56.9% of participants were women. Mean age 67.07 years. In Albacete province, 4.4% of the population over 50 years have a bowel habit consistent with constipation. Most participants had three meals a day (breakfast, lunch, and supper), while 50% had another meal in the morning or afternoon. These meals took place, habitually, in the domicile. There was a preponderance in daily intake of the following foods: milk (83.7%), bread (95.1%), vegetables (68.8%), fruit (91.8%), and virgin olive oil (96.6%). Fish was eaten every one to two days, and pulses and meat every three to six days. 44.4% of participants drank one to two liters of water a day. Only 3.9% of participants took some supplement; 35% of participants were on a diet. It was observed that 97.7% of participants with more than three defecations a week had a high intake of virgin olive oil; 65.7% of participants did some physical exercise customarily; 70.2% of participants were non-smokers, 10.2% were smokers, and 18.4% were ex-smokers. With regard to alcohol, the percentage of drinkers was 35.1%. The main class of medications taken by participants was NSAIDs - 14.5%; 79.7% took neither NSAIDs nor laxatives. Only 2.7% of participants took laxatives regularly. CONCLUSIONS: Most participants had relatively healthy eating habits.  相似文献   
105.
BACKGROUND: The exercise test has a recognized lower risk of complications when used in the general population and in coronary artery diseased patients, but from a theoretical point of view should have a higher rate of complications when performed in patients with chronic heart failure (CHF). AIMS: To characterize and assess the type and incidence of complications during cardiopulmonary stress test (CPX) in patients with depressed left ventricular systolic function in comparison with a group of patients and individuals with normal function. METHODS: Retrospective analysis of the 334 consecutive CPX performed for risk stratification in 198 patients with a left ventricular ejection fraction below 40% (Group A) and 180 consecutive CPX performed in 78 subjects with normal function (Group B). The two groups were compared with respect to demographic data, CPX parameters and specific complications. Results: Major complications during the tests occurred only in 14 tests of Group A (4.2%, p = 0.012). Non-sustained ventricular tachycardia, <6 beats, occurred in 7 group A and 2 group B tests. The absence of coronary artery disease was the only independent predictor for complications. CONCLUSIONS: Major CPX complications occurred only in patients with impaired left ventricular systolic function. Heart failure patients showed a low probability (around 4%) for complications during CPX, significantly higher and more severe than the risk in the group of patients with normal ventricular function, allowing us to recommend that CPX in patients with heart failure should be performed in a hospital setting under the supervision of a physician with specific training.  相似文献   
106.
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies. Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor, although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value of the endoscopic appearance was superior to endoscopic biopsy in this series. Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003. Supported by FADA-CAPES/PROP 200J (M.L.D.).  相似文献   
107.
108.
Summary We have studied the results of carotid occlusion in the treatment of giant intracavernous carotid artery (ICA) aneurysms in 40 patients. Clinical, angiographic, Doppler and cerebral blood flow (CBF) criteria for tolerance of occlusion are discussed. The patients had headaches (47.5%), cranial nerve compression (87.5%), decreased visual acuity (20%), ruptured aneurysm (15%) and 5% were asymptomatic. Balloon occlusion tests were performed under light sedation anaesthesia: a successful test required perfect clinical tolerance and adequate angiographic collateral circulation in arterial, parenchymatous, and venous phases. Additional criteria include xenon 133 CBF measurements, and transcranial Doppler sonography of the middle cerebral artery. According to these criteria, 5 patients did not tolerate test occlusion and required an extra-intracranial (EC-IC) bypass. Mean follow-up was 4.7 years. All patients were radiologically cured of their ancurysm, and in 35 the symptoms resolved, although 3 had persistent ocular motor nerve palsies, and in 4 visual defects were unchanged. Complications were 1 permanent and 3 transient neurological deficits. Balloon occlusion of the ICA is an effective, reliable form of treatment for intracavernous giant aneurysm and should replace surgical ligation of the cervical carotid artery. With CBF or Doppler monitoring, the risk of neurological deficit is diminished. EC-IC bypass prior to ICA occlusion is indicated if test occlusion is not tolerated.  相似文献   
109.
Summary We have studied the characteristics of arthritis present in 32 patients with Behçet's disease (BD), and how this arthritis is related to the HLA markers class I. 84% of the patients presented arthritis, the most common being monoarthritis as the initial presentation, and oligoarthritis in subsequent episodes. In 63% of the cases, the development was in episodes of acute/subacute arthritis. We found statistically significant association between antigens B-5 and B-51, and the group with BD, with a relative risk of 3.89 and 4.71 respectively. The attempt to relate markers B-5, B-51 and B-27 to the presence of arthritis as well as to its manifestation and further development was not conclusive.  相似文献   
110.
Mantle cell lymphoma is non-Hodgkin's B-cell lymphoma characterized by the t(11;14)(q13;q32) translocation. Peripheral blood involvement of mantle cell lymphoma is usually associated with a poor prognosis and therefore, its identification is clinically important. In this study, we performed cyclin D1/IgH-probe fusion fluorescence in situ hybridization analysis on 223 peripheral blood samples: 185 from 125 mantle cell lymphoma patients, and 38 normal controls. The cutoff values for the test were established using normal controls. Flow cytometry on peripheral blood and corresponding bone marrow samples was used to evaluate this test. In all, 26% of the 185 peripheral blood samples and 27% of the 161 corresponding bone marrow samples were flow cytometry positive for mantle cell lymphoma. The mean numbers of single and- double-fusion signals and the mean number of CD5/CD19-positive cells, absolute blood lymphocyte count, and white blood cell count were significantly higher in peripheral blood and corresponding bone marrow samples with mantle cell lymphoma-positive flow cytometry. Double-fusion signals were more specific than single-fusion ones. Fluorescence in situ hybridization was far more likely to be positive for mantle cell lymphoma when the peripheral blood and the corresponding bone marrow samples had positive flow cytometry results or morphology (P<0.01). Our study indicates that cyclin D1/IgH-fusion fluorescence in situ hybridization analysis could be used to determine the presence and character of circulating mantle cell lymphoma cells in peripheral blood, thus enhancing our ability to evaluate leukemic mantle cell lymphoma and minimum residual disease.  相似文献   
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