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41.
Focal nodular hyperplasia occurring after blunt abdominal trauma   总被引:2,自引:0,他引:2  
Focal nodular hyperplasia of the liver is a benign neoplasm. The pathogenesis is unknown, but it was hypothesized that focal nodular hyperplasia may be a response to a vascular abnormality. We report on a case of focal nodular hyperplasia that developed in a young patient 1 year after a blunt hepatic injury.  相似文献   
42.
OBJECTIVE: Using an isolated non-working rat heart model, this study investigated the mechanisms of pharmacological preconditioning (PC) induced by transient beta1-adrenoreceptor (beta1-AR) stimulation with xamoterol (XA). METHODS: After 6-hydroxydopamine (6-OHDA) pretreatment and a 20-min stabilization period, hearts were perfused at constant pressure for 20 min then subjected to 40 min of global ischemia and 30 min of reperfusion (I/R, Ctrl); exposed to 0.01 microM XA for 5 min with or without 10 microM atenolol (ATE), a specific antagonist of beta1-AR, followed by a 15-min XA-free perfusion before I/R (PC, ATE-PC, respectively); treated during 20 min with either phosphoinositide (PI) 3-kinase inhibitors, LY-294002 (LY, 15 microM), or wortmaninn (WO, 0.1 microM); protein kinase C (PKC) inhibitor, GF-109203X (GF, 4 nM); or protein kinase A (PKA) inhibitor, H89 (H89, 1 microM), with an infusion starting 3 min before XA (LY-PC, WO-PC, GF-PC, and H89-PC, respectively). The main endpoints were the mean coronary flow (MCF), the left ventricular end-diastolic pressure (LVEDP), rate-pressure product (RPP), and creatine kinase (CK) release. RESULTS: XA induced an increase in the MCF after I/R (t 105 min) and a protective effect on the LVEDP, which were blocked by ATE and abolished with the different inhibitors. The transient increase in RPP following XA infusion was blocked by ATE and was not modified by the inhibitors except for H89. Recovery of RPP, measured 25 min after reperfusion, was improved by XA, blocked by ATE, and decreased with the different inhibitors. Fifteen minutes after the end of ischemia, CK release reached maximal values in all groups. XA provided significant protection whereas ATE and the four inhibitors suppressed XA-induced protection. CONCLUSION: The transient preischemic exposure to nanomolar concentrations of a beta1-AR agonist is protective against I/R. PI 3-kinase, PKC, and PKA are implicated in the trigger phase of PC. These observations were confirmed by Western blots.  相似文献   
43.
Short-chain fatty acids are the main end products of bacterial fermentation of carbohydrates. Their role on the metabolism and biology of colonocytes is now well characterized. However, the functional consequences of their presence on intestinal smooth muscle cells remain poorly studied. We aimed to assess the effect of different short-chain fatty acids on ileal and colonic smooth muscle cells in primary culture and on A7R5 line. Butyrate (above 0.1 mM) inhibited A7R5 cell proliferation, while at low concentration (0.05 to 0.5 mM) butyrate significantly stimulated the proliferation of ileal and colonic myocytes in primary culture. An inhibition was observed at higher concentrations. Collagenous and noncollagenous protein synthesis was stimulated by butyrate. Moreover, butyrate stimulated actin and myosin expression. Thus, butyrate, which is produced by dietary fiber fermentation, may affect intestinal muscles by directly acting at the molecular level on myocytes.  相似文献   
44.
Vascular tumors of the liver in adult patients include cavernous hemangioma, a common benign tumor; epithelioid hemangioendothelioma, a rare, usually low-grade malignant tumor; and angiosarcoma, a rare and very aggressive tumor. All these primary mesenchymal tumors develop on a normal liver and may also affect other organs. Their pathogenesis remains largely unknown. Hepatic tumors are increasingly detected incidentally due to widespread use of modern abdominal imaging techniques. Therefore, reliable noninvasive characterization and differentiation of such liver tumors is of major importance for clinical practice. Hemangioma follows a benign course, and a nonoperative approach for the majority of these lesions is recommended. A definitive diagnosis of epithelioid hemangioendothelioma and angiosarcoma requires histopathologic examination. Liver transplantation at an early stage has greatly improved the prognosis of epithelioid hemangioendothelioma. The prognosis of angiosarcoma remains dismal. Designing a worldwide database that contains all data about patients with these rare diseases is recommended.  相似文献   
45.
AIM: The main aim of this study was to evaluate efficacy and therapeutic impact of capsule endoscopy (CE) in obscure gastrointestinal bleeding (OGIB). In addition, we evaluated the software of automatic detection of red zones (SBI, Given Imaging). PATIENTS AND METHODS: From June 2002 to June 2003, thirty-five patients with OGIB underwent capsule endoscopy after negative upper and lower digestive endoscopy. Capsule endoscopy was performed following a 12-hour fasting period and some received 2 L of PEG the night before for bowel preparation. RESULTS: CE was performed for occult (N=18) or overt (N=17) OGIB. Potentially bleeding lesions were found in 16/35 patients (45.7%). Lesions were angiodysplasias (N=8), ulcerations (N=4), tumors (N=2) and active bleeding without visible lesion (N=2). Lesions were located in gastric antrum (N=1), duodenum (N=2) and jejuno-ileum (N=13). Endoscopic (N=10), surgical (N=2) or medical (N=1) treatments were performed in 13/35 (37%). SBI was retrospectively evaluated in 24 patients with sensitivity, specificity, positive and negative predictive value of respectively 45%, 73%, 50% and 69%. CE retention during 10 days occurred in a patient with a small bowel NSAID-induced stricture. CONCLUSION: CE is a safe and effective procedure in the management of OGIB and had a therapeutic impact in more than one third of patients.  相似文献   
46.
The authors report the cases of two unrelated children 16 and 5 years of age respectively, affected with hypertyrosinaemia type II. This condition is characterized by palmo-plantar hyperkeratosis associated with a herpetiform keratitis. The diagnosis is based on the finding of hypertyrosinaemia and hypertyrosyluria, and may be confirmed by their biopsy findings of a cytoplasmic tyrosine amino-transferase deficiency. It is a hereditary autosomal recessive disease. A low phenylalanine and tyrosine diet produced a spectacular improvement but the ocular complications could have been avoided by an earlier diagnosis.  相似文献   
47.
Antibiotic-resistant soil bacteria in transgenic plant fields   总被引:1,自引:0,他引:1  
Understanding the prevalence and polymorphism of antibiotic resistance genes in soil bacteria and their potential to be transferred horizontally is required to evaluate the likelihood and ecological (and possibly clinical) consequences of the transfer of these genes from transgenic plants to soil bacteria. In this study, we combined culture-dependent and -independent approaches to study the prevalence and diversity of bla genes in soil bacteria and the potential impact that a 10-successive-year culture of the transgenic Bt176 corn, which has a blaTEM marker gene, could have had on the soil bacterial community. The bla gene encoding resistance to ampicillin belongs to the beta-lactam antibiotic family, which is widely used in medicine but is readily compromised by bacterial antibiotic resistance. Our results indicate that soil bacteria are naturally resistant to a broad spectrum of beta-lactam antibiotics, including the third cephalosporin generation, which has a slightly stronger discriminating effect on soil isolates than other cephalosporins. These high resistance levels for a wide range of antibiotics are partly due to the polymorphism of bla genes, which occur frequently among soil bacteria. The blaTEM116 gene of the transgenic corn Bt176 investigated here is among those frequently found, thus reducing any risk of introducing a new bacterial resistance trait from the transgenic material. In addition, no significant differences were observed in bacterial antibiotic-resistance levels between transgenic and nontransgenic corn fields, although the bacterial populations were different.  相似文献   
48.
We present 2 cases of hepatocyte nuclear factor 1α (HNF1α)-mutated adenomatosis, discovered for reasons unrelated to this disease, and identified using immunohistochemical methods. These new tools may further our understanding of the link between adenomas/adenomatosis subtypes and their complications, and their association with other abnormalities.  相似文献   
49.
Our aim in this study was to examine the relationship between regular exercise and major cardiovascular events in hypertensive elderly with established coronary heart disease (CHD) in the primary care setting. The PREHACOR study recruited 3193 hypertensive patients, aged 74 ± 6 years, 67% male, with CHD. Regular exercise assessed by questionnaire was defined as recreational activity >20 min/day, >3 times/week. Endpoints at 6 months were new cardiovascular events (NCEs: myocardial infarction and hospitalization for stroke, unstable angina, congestive heart failure, or coronary revascularization). New cardiovascular events occurred in 376 patients (11.8%), with 17 deaths (0.5%). New cardiovascular events patients were older, with higher body mass index, and were more likely to have diabetes, arrhythmia, history of congestive heart failure, and noncardiac organ damage than non-NCE patients. Blood pressure was significantly and similarly reduced in both groups. Multivariate logistic regression associated NCEs positively and independently with a history of congestive heart failure (odds ratio [OR] 2.50; confidence interval [CI] = 1.9–3.23), noncardiac target organ damage (OR 1.51; CI = 1.20–1.90), and beta-blocker use (OR 1.28; CI = 1.02–1.59), and inversely and independently with combination low-dose angiotensin converting enzyme inhibitor + diuretic therapy (OR 0.66; CI = 0.45–0.95) and regular exercise (OR 0.70; CI = 0.54–0.90). Regular exercise is significantly associated with fewer major cardiovascular events in hypertensive elderly subjects with established CHD.  相似文献   
50.
Central illustration. Time of occurrence and outcome of cardiovascular disorders in patients (pts) with congenital portosystemic shunt (CPSS). Patients with normal anatomy and those with congenital heart disease (CHD) were distinguished. Heart failure (HF) was the main symptom in both the prenatal and neonatal periods, whereas portopulmonary hypertension (PPH) and hepatopulmonary syndrome (HPS) represented the major concerns beyond the first months of life. CV: cardiovascular; NAS: no additional symptoms; PH: pulmonary hypertension; RD: respiratory distress. aFetal diagnosis of CPSS. bNeonatal diagnosis of CPSS. cDiagnosis of CPSS > 1 month of age
  相似文献   
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