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81.
OBJECTIVES: We conducted an acute experimental study to test the feasibility of dynamic cardiomyoplasty in a setting of modified Fontan procedure for univentricular heart with pulmonary hypertension to obtain a possible proxy for high-risk Fontan candidates. METHODS: After electrical preconditioning of the left latissimuss dorsi for 6 weeks in 8 dogs, the right ventricular cavity was totally obliterated with concomittent closure of the tricuspid valve and right pulmonary artery. Modified Fontan circulation was established with the aortic homograft anastomosed between the right atrium and pulmonary trunk, incorporated with a pericardial pouch as a compression chamber (neoright ventricle) fixed onto the epicardial surface of the ventricle. After cardiopulmonary bypass termination, a latissimus dorsi was applied to wrap the pericardial pouch and ventricle clockwise and stimulated with a trained-pulse (25 Hz) at 1:1 synchronization ratio with cardiac beats. RESULTS: Profound right heart failure was noted during Fontan circulation in increased pulmonary vascular resistance (11 +/- 3.2 Wood units), whereas graft pacing showed significant augmentation of systolic pulmonary pressure by 54 +/- 12%, the mean pulmonary flow by 68 +/- 23%, and aortic pressure by 23 +/- 5% at a physiological range of central venous pressure (13.2 +/- 0.7 mmHg). Right heart function curve analysis confirmed marked augmentation of right heart performance, restoring almost normal pulmonary circulation. These functional benefits were sustained up to 4 hours in 4 animals until experiments were terminated. CONCLUSIONS: Dynamic cardiomyoplasty in a modified Fontan procedure is a viable surgical option for univentricular heart, not a Fontan candidate.  相似文献   
82.
Terminal liver cirrhosis is associated with marked severe portal hypertension, which increases the risk of intraoperative hemorrhage and graft hyper-perfusion, especially, in small-for-size graft. In cases with developed collateral vessels, we often face difficulties in perihepatic dissection with blood stanching against bleeding during recipient hepatectomy. For aseptic preoperative portal decompression, we established the proximal splenic artery embolization (PSAE) technique. Sixty adult living donor liver transplantation recipients with viral/alcoholic hepatic failure were divided into two groups; PSAE group (n = 30) and non-PSAE (n = 30). In the PSAE group, the splenic artery was embolized proximal to the splenic hilum 12-18 h before surgery. PSAE enabled shortening of operating time, reduced blood loss, led to less need for transfusion, and significantly reduced the post-transplant portal venous velocity and ascites. PSAE was not associated with complications, e.g., splenic infarction, abscess, or portal thrombosis. Six of the non-PSAE patients required additional surgical intervention to resolve postoperative hemorrhage and three patients required secondary PSAE for arterial-steal-syndrome. The hospital mortality rate of PSAE patients (3.3%) was significantly better than that of the PSAE group (13.3%, P < 0.05). Preoperative noninvasive PSAE makes more efficient use of portal decompression; thus, it can potentially contribute to improvement of outcome.  相似文献   
83.
Calcium deposition in the skin, known as calcinosis cutis, is an uncommon disorder caused by an abnormal deposit of calcium phosphate in the skin. We report a case of idiopathic calcinosis cutis in fingertip treated with surgical excision followed by the occlusive dressing using aluminum foil, and obtained significant pain relief and round-shaped fingertip which looked normal.  相似文献   
84.
We describe the case of a patient with a diaphragmatic hernia associated with radiofrequency ablation for hepatocellular carcinoma who was successfully treated by laparoscopic surgery. A 62-year-old man with a long history of hepatitis C-induced liver cirrhosis was admitted to our institution because of recurrent postprandial periumbilical pain. Eight years earlier, he had undergone radiofrequency ablation for hepatocellular carcinoma at hepatic segment VIII. Computed tomography, gastrografin enema examination revealed transverse colon obstruction because of a diaphragmatic hernia. We diagnosed diaphragmatic hernia associated with the prior radiofrequency ablation treatment. The patient underwent laparoscopic repair of the diaphragmatic hernia. Though the patient experienced the recurrence once, relaparoscopic treatment has improved the patient''s conditions. Thus, diaphragmatic hernia can develop as a complication of radiofrequency ablation treatment. A laparoscopic approach is safe, feasible, and minimally invasive, even in patients with cirrhosis who develop iatrogenic diaphragmatic hernia as a complication of radiofrequency ablation treatment.Key words: Diaphragmatic hernia, Radiofrequency ablation, Complication, Laparoscopic surgeryAlthough surgery is accepted as the first-line treatment for hepatocellular carcinoma (HCC) and colorectal metastases that are limited in number, radiofrequency ablation (RFA) is an effective treatment option for patients with primary and metastatic liver tumor, who are not surgical candidates because of tumor location, poor hepatic reserve, or advanced age.1,2,3 Chen et al conducted a prospective randomized trial comparing RFA with hepatectomy; however, they were not able to determine whether on treatment alternative was superior to the other.4 RFA treatment is the best option among the locoregional treatments for HCC.5,6 According to the HCC treatment algorithm in the National Comprehensive Cancer Network guideline, RFA treatment should be chosen as a locoregional therapy depending on the degree of liver damage. Tumors ≤ 3 cm are optimally treated with ablation.7 RFA for hepatic tumors is a relatively safe modality with a reported overall complication rate of 7.1% and a very low mortality rate (0.3%);8 however, the guideline reinforces awareness of the major vessels, major bile ducts, diaphragm, and other intra-abdominal organs.7Diaphragmatic hernia is defined as out-pocketing of abdominal contents into the thoracic cavity, through a defect in the diaphragm. However, most of the acquired diaphragmatic hernias are caused by penetrating or blunt traumatic injury and are rarely caused by surgical procedures such as gastric banding or abdominal surgeries (e.g., nephrectomy).4,9 Especially, the appearance of a diaphragmatic hernia after RFA treatment is quite rare and clinically unrecognized as a complication of RFA.10 Surgical intervention is the best single treatment for the permanent cure of a diaphragmatic hernia. Among the surgical procedures, open laparotomy for diaphragmatic hernia has been widely accepted; however, only 1 case of liver cirrhosis and HCC has been reported, in which a laparoscopic approach was used to treat the diaphragmatic hernia associated with RFA treatment.10 We report the case of a patient with a diaphragmatic hernia caused by RFA treatment for HCC with cirrhosis, who was successfully treated with laparoscopic surgery.  相似文献   
85.
Vascular calcification (VC) is a life-threatening complication of CKD. Severe protein restriction causes a shortage of essential amino acids, and exacerbates VC in rats. Therefore, we investigated the effects of dietary l-lysine, the first-limiting amino acid of cereal grains, on VC. Male Sprague-Dawley rats at age 13 weeks were divided randomly into four groups: low-protein (LP) diet (group LP), LP diet+adenine (group Ade), LP diet+adenine+glycine (group Gly) as a control amino acid group, and LP diet+adenine+l-lysine·HCl (group Lys). At age 18 weeks, group LP had no VC, whereas groups Ade and Gly had comparable levels of severe VC. l-Lysine supplementation almost completely ameliorated VC. Physical parameters and serum creatinine, urea nitrogen, and phosphate did not differ among groups Ade, Gly, and Lys. Notably, serum calcium in group Lys was slightly but significantly higher than in groups Ade and Gly. Dietary l-lysine strongly suppressed plasma intact parathyroid hormone in adenine rats and supported a proper bone-vascular axis. The conserved orientation of the femoral apatite in group Lys also evidenced the bone-protective effects of l-lysine. Dietary l-lysine elevated plasma alanine, proline, arginine, and homoarginine but not lysine. Analyses in vitro demonstrated that alanine and proline inhibit apoptosis of cultured vascular smooth muscle cells, and that arginine and homoarginine attenuate mineral precipitations in a supersaturated calcium/phosphate solution. In conclusion, dietary supplementation of l-lysine ameliorated VC by modifying key pathways that exacerbate VC.Medial vascular calcification is common in aging, diabetes, and CKD.14 Because the presence of vascular calcification is strongly associated with increased cardiovascular morbidity and mortality, several studies in both animals and humans have sought ways to reduce the extent of vascular calcification.510 However, satisfactory therapies have not yet been established.11Adenine-induced renal failure is one of the commonly used animal models for studying the development of vascular calcification, but the prevalence of vascular calcification in this model is not very high. Indeed, Price et al. reported that vascular calcification was detected in only 30% of rats with adenine-induced chronic renal failure (adenine rats) fed a normal-protein diet.5 These authors speculated that consistent vascular calcification might require a longer period of adenine feeding. On the basis of this idea, they designed a low-protein (LP) diet in an attempt to reduce the nitrogen load and thus enable the rats to thrive on the adenine diet for longer periods. As a result of this attempt, Price et al. unexpectedly found that adenine rats fed a LP diet had extensive vascular calcification without a longer feeding period.5 All 13 adenine rats fed the LP diet had uniform alizarin red staining of the aorta, whereas only 3 of the 11 adenine rats fed a normal-protein diet had partial calcification.5 These findings indicated that dietary protein deficiency correlates with the extent of vascular calcification.Proteins are usually made from 20 kinds of amino acids. On the basis of nutritional requirements, these amino acids can be divided into two groups: essential amino acids (EAAs) and non-EAAs. Because restriction of dietary protein results in a shortage of EAAs, the level of dietary EAAs may be relevant to the extent of vascular calcification. Among nine EAAs, this study focused on l-lysine (l-Lys) based on the following three reasons. First, l-Lys is the first-limiting amino acid in most cereal grains.12 Second, the safety of l-Lys supplementation has been verified in the area of animal husbandry. l-Lys has long been added to feed grains in order to improve the utility of feed proteins.13 Third, several studies have demonstrated that dietary supplementation with l-Lys protects bones from osteoporosis, a pathologic condition that often coexists with vascular calcification.14,15 These points prompted us to hypothesize that supplementation with l-Lys would ameliorate vascular calcification. Therefore, in this study, we tested this hypothesis using adenine rats.  相似文献   
86.
BACKGROUND: Exercise intolerance of the hand after harvest of the radial artery is not well understood, although mild reductions of blood flow to the hand are reported. To ascertain its prevalence, patient symptoms implying potential exercise intolerance were evaluated by measuring transcutaneous oxygen pressure of the hand during grip exercise. For ascertaining predictive values, we verified ulnar flow reserve measured by Doppler ultrasonography before the harvest of radial artery. METHODS: Forty patients whose radial artery was harvested for coronary bypass graft, were interviewed and tested 1 year after operation, and their preoperative ultrasonographic data compared. RESULTS: Five patients (12.5%) had mild symptoms implying exercise intolerance. Exercise tests revealed severe decreases in tissue oxygenation in 7 patients (17.5%), but in accordance with symptoms (p = 0.0018). Tissue oxygenation in the operated hand was lower than in the nonoperated even in asymptomatic patients (p = 0.0011). Preoperative Doppler echography revealed that ulnar arteries of symptomatic patients were smaller (p = 0.0019) and carried lower blood flows during manual compression of the radial artery (p = 0.0004) compared with those of asymptomatic patients. Smaller ulnar arteries (less than 1.4 mm/m(2)) with poor flow reserves (less than 60 mL x min(-1) x m(-2) during radial compression) appear to indicate risks for exercise intolerance (p = 0.0004). CONCLUSIONS: More than 10% of patients after harvest of radial arteries had mild symptoms implying exercise-intolerance, which accorded with abnormal tissue oxygenation during grip exercise. Work habits of patients should be considered in radial harvest decisions, especially if preoperative Doppler echography indicates lower flow reserves for the ulnar artery.  相似文献   
87.
Skip mediastinal nodal metastases in non-small cell lung cancer   总被引:1,自引:0,他引:1  
Objective: To reveal the incidence and clinical significance of mediastinal nodal metastases without N1-station nodal metastases (‘skip-N2 metastases’) in non-small cell lung cancer (NSCLC). Methods: A total of 450 NSCLC patients who underwent tumor resection with a systemic mediastinal nodal dissection were retrospectively reviewed. p53 status and proliferative activity represented as proliferative index (PI) were also examined immunohistochemically. Results: Skip-N2 metastases were documented in 49 (13%) patients of all 450 patients; among 334 patients without N1-nodal involvement, 18% patients had skip-N2 metastases. The postoperative survival of skip-N2 patients was almost same as that for patients with metastases to both N1 and N2 nodes. Skip-N2 metastases were significantly more frequent in male patients and squamous cell carcinoma patients. In addition, the mean PI for tumor with skip-N2 metastases was significantly higher than that for any other pathologic nodal (pN)-status diseases. Combined with histologic type and PI, the incidences of skip-N2 metastases for adenocarcinoma showing lower PI were only 5% (7/137) of all patients and 7% (7/94) of patients without N1-nodal involvement. Conclusions: N1 nodal status is not a useful predictor of N2 nodal status in NSCLC, because skip-N2 metastases were documented in 18% patients showing no N1-nodal involvement. However, N1 node-guided dissection might be performed in patients with adenocarcinoma showing lower PI, because the incidence of skip-N2 metastases was extremely low.  相似文献   
88.
PURPOSE: The aim of this study is to clarify the causes of exercise-induced ST-segment depression in patients with broad lateral old myocardial infraction involving LCX (LCX-OMI) without ischemia on exercise scintigraphy. METHOD: Twenty one patients (M/F = 11/10, age = 62 +/- 19 years) with myocardial infraction involving LCX (LCX-MI), but without fill-in on exercise and rest MIBI quantitative gated SPECT (QGS), were selected. They were divided into two groups of Group ST(+) (n = 11, with significant ST depression (max -2.8 +/- 0.4 mm), Group ST(-) (n = 10) without ST depression. On 20 SPECT segments of both exercise and rest SPECT, we scored uptake score as DS (0 = normal to 3 = defect) and wall motion as WMS (0 = normal to -5 = dyskinesis) and summed DS (TDS) and WMS (TWMS) in LCX region, furthermore, calculated the difference of TWMS (delta TWMS [exercise-rest]), end diastolic volume (EDV) and ejection fraction (EF) during exercise were compared between the two groups. RESULT: Group ST(+) showed significantly (p < 0.01) lower EF (35.4 +/- 9.2% vs. 60.2 +/- 6.2%), larger EDV (146 +/- 53 ml vs. 93 +/- 15 ml), higher TDS (5 vs. 7 +/- 3), lower TWMS (-25 +/- 9 vs. -6 +/- 5), furthermore lower delta TWMS (-6.9 +/- 4.0 vs. -2.0 +/- 0.8) than Group ST(-). CONCLUSION: Exercise-induced significant ST depression in V2-4 without ischema in LCX-MI was observed in patients with broad LCX-MI, low EF, and was related to impaired wall motion in LCX region. ST depression in V2-4 was considered to appear as miller image of ST elevation at postero-inferior wall due to disturbed wall motion on exercise.  相似文献   
89.
OBJECTIVE: We examined the possibility of intraoperative ultrasonography during video-assisted thoracic surgery (VATS) to localize and make a qualitative diagnosis of small peripheral pulmonary nodules. METHODS: Ultrasonography during VATS and conventional thoractomy was performed on 25 and 18 nodules, respectively, all which were localized in the peripheral lung, were less than 30 mm in diameter and for which there was no definitive diagnosis. RESULTS: All 25 nodules, including 10 invisible but palpable and three both invisible and non-palpable, could be localized by ultrasonography during VATS. If nodules were located less than 15 mm from the pleural surface, ultrasonography during VATS could detect nodules 10 mm or less in diameter. The rate of malignant tumors among 11 of 12 pulmonary nodules (91.6%) showing both heterogeneous and ill-defined patterns was significantly higher than 6 of 16 nodules (37.5%) showing both homogeneous and well-defined patterns on ultrasonography. CONCLUSIONS: Our study suggested that ultrasonography during VATS is useful for the detection of peripheral pulmonary nodules, even when they are not identified on video images or palpation, and may enable a differential diagnosis between malignant and non-malignant lesions.  相似文献   
90.
IntroductionLong-term follow-up studies focusing on the posterior extensor muscles in patients suffering from whiplash injury are scarce. The purpose of this study was to elucidate the changes in the posterior extensor muscles 10 years after whiplash injury.MethodsTwenty-three patients who had suffered from whiplash injury in 1994–1996 and had undergone MRI using a 1.5-T superconductive imager participated in this follow-up study (13 males, 10 females, mean age 51.8 years, mean follow-up 11.5 years). In addition, 60 healthy volunteers who had undergone MRI in the same period were included as controls (36 males, 24 females, mean age 47.8 years, mean follow-up 11.1 years). All participants underwent follow-up MRI. The cross-sectional areas of the deep posterior muscles (CSA) including the multifidus, semispinalis cervicis, semispinalis capitis, and splenius capitis were digitally measured at C3-4, C4-5, and C5-6 using NIH image. The long-term changes in the CSA were compared between the two groups. In addition, correlations between the CSA and cervical spine-related symptoms were evaluated.ResultsThe mean total CSA per patient (the sum of the area from C3-4 to C5-6) was 4811.6 ± 878.4 mm2 in the whiplash patients and 4494.9 ± 1032.7 mm2 in the controls at the initial investigation (p = 0.20), and 5173.4 ± 946.1 mm2 and 4713.0 ± 1065.3 mm2 at the follow-up (p = 0.07). The mean change in CSA over time was 361.8 ± 804.9 mm2 in the whiplash patients and 218.1 ± 520.7 mm2 in the controls (p = 0.34). Ten whiplash patients (43.5%) had neck pain and 11 (47.8%) had shoulder stiffness. However, there was no difference in the change in CSA over time between the symptomatic and asymptomatic patients.ConclusionsThere was no significant difference in the change in CSA between whiplash patients and healthy volunteers after a 10-year follow-up period. In both groups, the cross-sectional area slightly increased at follow-up. In addition, there was no association between the change in CSA and clinical symptoms such as neck and shoulder pain. These results suggest that whiplash injury is not associated with symptomatic atrophy of the posterior cervical muscles over the long term.  相似文献   
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