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91.
OBJECTIVE: Total correction of classical tetralogy of Fallot (TOF) by transatrial approach has become a standard procedure in the goal to minimize structural damage to the pulmonary pump. The most critical point in transatrial repair of TOF is infundibular dissection. Right atrial approach provides better surgical exposure for parietal extension of the infundibular septum when compared to the right ventricular approach. However it is not always easy to determine the localization and amount of muscle bundles to be resected and this surgical maneuver requires experience. METHODS: Nineteen patients who had repair of isolated TOF using this technique from 1993 to 2001 were reviewed. The mean age of patients were 5 +/- 2 years. Transatrial-transpulmonary approach were performed for all patients. To make easier the infundibular muscle bundles resection and to determine the localization and amount of muscle bundle to be resected, we placed a Hegar dilator into the right ventricle through pulmonary arteriotomy. The muscle bundles between the dilator and the anterior leaflet annulus of the tricuspid valve were totally excised until the intraventricular part of the dilator and pulmonary annulus became completely visible. The area between the Hegar dilator and the margins of the ventricular septal defect (VSD) was left untouched. None of the patients had transannular patch. To improve exposure, tricuspid valve detachment was performed in 11 patients. All patients were followed-up in our clinic every 6 months using echocardiography. RESULTS: There were no early or late deaths, and no reoperation for residual VSD or residual right ventricle (RV) outflow obstruction. All patients were in NYHA Class I. RV on the echocardiography was spared late dilatation and had a good late functional status. Eighteen patients had no or mild pulmonary regurgitation. One patient who had undergone tricuspid anterior leaflet detachment showed mild tricuspid insufficiency. CONCLUSION: On the basis of hemodynamic outcomes, this procedure for elective repair of TOF in selected cases shows excellent early and mid-term results.  相似文献   
92.
OBJECTIVE: To review the clinical management of alveolar echinococcosis. DESIGN: A retrospective analysis. SETTING: A university-affiliated hospital in Turkey. PATIENTS: Forty patients treated for alveolar echinococcosis between 1987 and 2000. INTERVENTIONS: Curative resection followed by chemotherapy, or medical palliation with chemotherapy only. Palliative procedures such as bilioenteric or external drainage were done for cholestatic jaundice and liver abscess. OUTCOME MEASURES: Results of medical and surgical treatment. RESULTS: Seventeen patients had a resectable tumour and all underwent curative resection. Of the other 23 patients with nonresectable tumour, 11 underwent palliative surgical procedures such as bilioenteric or external drainage for cholestatic jaundice or liver abscess. All patients received long-term albendazole therapy. Four patients with nonresectable tumour died because of chronic liver failure. In a 6.5-year follow-up, there was no recurrence in patients who underwent curative resection. The efficacy of chemotherapy is limited in nonresectable disease. CONCLUSIONS: To increase the rate of early detection and curative resection, screening programs are essential. Research on new chemotherapeutic approaches should be made to improve survival in patients with nonresectable disease.  相似文献   
93.
The plasma concentration of asymmetrical dimethylarginine (ADMA), an inhibitor of nitric oxide synthase, has been linked to endothelial dysfunction. We investigated the relation between plasma ADMA concentration and severity of erectile dysfunction (ED) and coronary artery disease (CAD). We measured plasma levels of ADMA in 92 male patients. Patients were divided into three groups: group 1 (n = 41), patients with ED and without CAD; group 2 (n = 29), patients with stable CAD; group 3 (n = 22), control group (patients without CAD or ED). Erectile function was evaluated by the erectile function domain of the international index of erectile function (IIEF-EFD) a validated 15-item self-administered questionnaire. Erectile function is specifically addressed by six questions that form the so-called erectile function domain of the questionnaire. Each question is scored 0–5. ED is defined as any value <26. Patients with CAD who have stable angina pectoris were selected after coronary angiography. ADMA was analyzed by ELISA method. Group 1 had significantly higher concentrations of plasma ADMA than groups 2 and 3 (respectively, 0.75 ± 0.40 vs. 0.50 ± 0.30, P = 0.013; 0.75 ± 0.40 vs. 0.50 ± 0.25, P = 0.021). There was negative correlation between ADMA and IIEF-EFD score in all groups (n = 92) (r = −0.322, P = 0.002). In a multiple logistic regression analysis adjusting for age, hyperlipidemia, ADMA remained independent predictor for severe ED. Odds ratio for plasma ADMA was 14.151 (1.101–181.940; P = 0.042). First of all, this study provides that ADMA concentrations are significantly higher in patients who have ED when compared to patients with CAD and controls. Second, there was a negative correlation between ADMA and severity of ED. Elevating levels of circulating ADMA is an independent risk factor for severe of ED, and ADMA may be a link between CAD and ED.  相似文献   
94.
Heterotopic pancreas is a relatively common variant of foregut embryologic dystopia that can be described as pancreatic tissue found outside the normal anatomic location, being independent from vascular supply of normal pancreas. Having all features of pancreatic tissue except for the major duct structures, this ectopic tissue may be clinically recognized when pathologic changes take place. Inflammation, hemorrhagic or obstructive states, and eventually malignancy-related problems may become a diagnostic challenge for clinician and finally lead to consequences of misdiagnosis. In this article we will discuss a case of heterotopic pancreatic tissue located in gastric cardia, which was diagnosed preoperatively as gastrointestinal stromal tumor.Key words: Ectopic pancreas, Pseudocyst, Gastrointestinal stromal tumor, MisdiagnosisHeterotopic (ectopic) pancreas is defined as the presence of pancreatic tissue in an aberrant site that is not anatomically and vascularly connected to the pancreas proper.1,2 Ectopic pancreatic tissue is most commonly found in the duodenum (particularly the second portion), ampulla, stomach (prepyloric antrum), and upper jejunum; it can also occur in the liver, biliary tract, Meckel''s diverticulum, and several other sites such as large bowel, spleen, omentum, mediastinum, lung, thyroid, and even brain.16 The heterotopic pancreatic tissue is usually located in the submucosa and/or the muscularis or subserosa.1,2,4Practically any pancreatic pathology can also occur in the heterotopic pancreatic tissue including acute pancreatitis and neoplastic transformation.1,4,7,8 Episodes of acute pancreatitis may cause local inflammation and typical pancreatitis-related complications in the host organ. The ectopic pancreatic tissue can lead to ulceration and bleeding in the cases located beneath a mucosa. Being a mass-forming lesion, it may also result in luminal obstruction (particularly in the prepyloric antrum).1,4Although it is a relatively common congenital anomaly (0.5% to 13% in autopsy series), in most cases heterotopic pancreas remains clinically silent and is found incidentally during surgery or an endoscopic and/or radiological investigation.1,9 Heterotopic pancreas may be confused with other solid tumors of the host organ.Heterotopic pancreas in the stomach is usually located in the prepyloric area.10 We report here an unusual case of heterotopic pancreas with a pseudocyst formation in the gastric cardia mimicking gastrointestinal stromal tumor.  相似文献   
95.
Implantable devices in direct contact with flowing blood are associated with the risk of thromboembolic events. This study addresses the need to improve our understanding of the thrombosis mechanism and to identify areas on artificial surfaces susceptible to thrombus deposition. Thrombus deposits on artificial blood step transitions are quantified experimentally and compared with shear stress and shear rate distributions using computational fluid dynamics (CFD) models. Larger steps, and negative (expanding) steps result in larger thrombus deposits. Fitting CFD results to experimental deposit locations reveals a specific shear stress threshold of 0.41 Pa or a shear rate threshold of 54 s?1 using a shear thinning blood viscosity model. Thrombosis will occur below this threshold, which is specific to solvent‐polished polycarbonate surfaces under in vitro coagulation conditions with activated clotting time levels of 200–220 s. The experimental and computational models are valuable tools for thrombosis prediction and assessment that may be used before proceeding to clinical trials and to better understand existing clinical problems with thrombosis.  相似文献   
96.
Gorgulu N, Yelken B, Caliskan Y, Elitok A, Cimen AO, Yazici H, Oflaz H, Golcuk E, Ekmekci A, Turkmen A, Yildiz A, Sever MS. Endothelial dysfunction in hemodialysis patients with failed renal transplants.
Clin Transplant 2009 DOI: 10.1111/j.1399‐0012.2009.01160.x
© 2009 John Wiley & Sons A/S. Abstract: Background: Endothelial dysfunction (ED) is a common precursor and denominator of cardiovascular events including development of atherosclerosis. In this cross‐sectional study, we aimed to investigate ED, measured by coronary flow reserve (CFR) in hemodialysis (nHD) patients who were never transplanted and patients with failed renal transplants restarting hemodialysis (fTx‐HD). Methods: Forty nHD (24 males, mean age 39 ± 9 yr) and 43 fTx‐HD patients (27 males, mean age 36 ± 9 yr) were included in the study. Clinical and biochemical parameters, including high‐sensitive C‐reactive protein (hs‐CRP) levels were determined. Also, CFR measurements were used to evaluate ED. Results: There were no significant differences regarding age, gender, smoking status, systolic and diastolic blood pressure levels, mean duration of HD treatment as well as Kt/V(urea) values between the two groups. Time spent on dialysis in the nHD group and dialysis duration following failure of renal allograft in the fTx‐HD group were similar. Serum creatinine, hemoglobin, hematocrit, calcium and phosphorus levels were similar between the two groups as well. When compared to nHD group, serum total cholesterol (139 ± 3 vs. 154 ± 3 mg/dL, p = 0.045), serum albumin (3.8 ± 0.3 g/dL vs. 4.1 ± 0.2 g/dL, p < 0.0001) and CFR (1.60 ± 0.2 vs. 1.75 ± 0.3, p = 0.028) levels were significantly lower, while serum hs‐CRP levels (11 ± 15 mg/L vs. 3 ± 4 mg/L, p = 0.001) were significantly higher in the fTx‐HD group. Serum hs‐CRP negatively correlated (r = ?0254, p = 0.021), while serum albumin positively correlated (r = 0402, p = 0.001) with CFR values. Conclusion: ED is more prominent in fTx‐HD than the nHD patients. Inflammation, caused by failed renal allograft can be responsible for this abnormality.  相似文献   
97.
Spinal osteochondromas are very rare, and they present with nonspecific localized pain owing to bone involvement. Diagnosis is made based on direct X-ray and computed tomography (CT) imaging of the exophytic bone lesion with pedunculated or sessile structure. Although asymptomatic patients can be observed, surgical excision is the main treatment modality. We present the case of a 34-year-old man with solitary thoracic osteochondroma. The patient presented with complaints of pain in the legs, numbness, and inability to walk. The diagnosis was confirmed with CT imaging showing calcified heterogeneous bone lesion originating from the left side of T1-2 facet joint. After total excision, histopathological examination revealed the diagnosis of osteochondroma. No new clinical or radiological findings were detected in the 10-month follow-up.  相似文献   
98.
In the study, the ameliorating effects of alfa lipoic acid (ALA) against doxorubicin-induced testicular apoptosis, oxidative stress and disrupted mitochondrial fusion were investigated in male rats. Rats were divided into four groups as control, doxorubicin (DOX), DOX + ALA and ALA. A single dose of 15 mg/kg DOX was administered i.p to the DOX and DOX + ALA groups. 50 mg/kg ALA was given to the DOX + ALA and ALA groups by oral gavage every other day. After 28 days, rat testes and serum samples were collected and analysed. Administration of DOX alone caused a decrease in body and relative testicular weights, seminiferous tubule diameter and germinal epithelium thickness, Johnsen's score and serum testosterone levels. DOX treatment led to severe testicular damage such as tubular degeneration, and atrophic tubules. Also, the activities of superoxide dismutase and glutathione peroxidase were reduced, while the level of malondialdehyde was increased in the testis. The mRNA levels of apoptotic-related genes (CASP3, TP53, BAX, BCL2) and apoptotic index were increased, while mitofusin-2 decreased. DOX caused an increase in CASP3 and a decrease in mitofusin-2 immunoreactivities. Treatment with ALA markedly improved all of DOX-induced biochemical, histochemical and molecular alterations in rat testis. Consequently, ALA has a therapeutic role in ameliorating DOX-induced testicular damage in rats.  相似文献   
99.
OBJECTIVES: The aim of this study was to compare the radiological outcome of open and close reduction and osteosynthesis methods in the treatment of type II and III supracondylar humerus fractures in childhood with respect to the immediate post-operative reduction quality in sagittal plane. METHOD: One hundred and forty four-pediatric patients with type IIb and III supracondylar humerus fractures treated at two centers between 1995 and 2005 were evaluated radiologically within a retrospective study. Seventy-six patients (54 boys, 22 girls, mean age 7.6, range 2-12) were treated by closed reduction and cross percutaneous pinning while 68 (49 boys, 19 girls, mean age 7.3, range 2-13) were treated by open reduction. The reduction quality of the open and closed groups was compared on immediate post-operative lateral radiographs by measuring of lateral humerocapitellar angle, anterior humeral line and anterior coronoid line criteria. The reduction quality was classified excellent, good, fair and poor according to the achievement of three, two, one or none of the criteria, respectively. Reductions classified as excellent and good were introduced as acceptable results. RESULTS: At least one criterion was achieved in all the patients of both the groups. The mean humerocapitellar angle was 30.1 degrees in closed reduction group while the mean of it was 29.8 degrees in open reduced group. Radiograph of 48 (63.1%) patients with closed reduction were found to display the anterior humeral line intersecting the middle one-third of capitellum while this criteria was 45 (66%) in open reduction group. The anterior coronoid line was disturbed in three patients in each of both the groups. The reduction quality was evaluated to be excellent in 32 patients, good in 31, fair in 13 at the closed reduction group while these evaluations were 31, 20 and 17 in open reduction group, respectively. Successful reduction was achieved in 74.9% of the patients in closed reduction group and 75% of the patients in open reduction group. CONCLUSION: It is concluded that there was no significant difference between closed and open reductions of pediatric displaced supracondylar fractures with regard to the radiological criteria of reduction quality in sagittal plane.  相似文献   
100.
OBJECTIVE: To determine the reliability of medial canthus as a surface landmark to locate supratrochlear vascular pedicle. STUDY DESIGN AND SETTING: The distance from medial canthal line to supratrochlear vascular pedicle was measured in 57 healthy volunteers (Doppler imaging study) and also in 15 fresh cadavers. RESULTS: In the Doppler study, the pedicle was found at most 3 mm lateral or medial to medial canthus (mean +/- SD, 0.8 +/- 0.7 mm). SVP mark tended to be medial to the medial canthus mark in females (males, 6; females, 42), whereas it was lateral to it in males (males, 20; females, 5). In the cadaver study, the pedicle was found 0.7 mm away from medial canthus on average. CONCLUSION: Medial canthus can be used as a reliable landmark for paramedian forehead flaps. When Doppler examination fails, pedicle may be found at most 3 mm away from medial canthus. SVP is more commonly located lateral to medial canthus in males and medial to it in females.  相似文献   
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