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11.
OBJECTIVES: To investigate the expression and clinical significance of MMP-2, MMP-7, MMP-9, and TIMP-1 in patients with nasal polyposis (NP) and chronic rhinosinusitis (CRS). STUDY DESIGN: Prospective study. SUBJECTS AND METHODS: This study involved 54 patients. There were three groups: nasal polyposis group, chronic rhinosinusitis group, and control group. Specimens were collected during endoscopic sinus surgery. Each sample was immunohistochemically examined. RESULTS: Expression of MMP-2 was found significantly increased in NP, whereas MMP-7 expression was found significantly increased in CRS (P < 0.001). TIMP-1 was significantly high in control group compared to CRS and NP (P < 0.001 and P = 0.002, respectively). CONCLUSIONS: Different regulation type of activation of MMPs has been found in these two diseases. If MMP-2 expression is intense in the mucosa, then this ends with polyp formation; if MMP-7 expression is intense, it ends with CRS or stays as CRS.  相似文献   
12.

Purpose

The aim of this study was to examine the effects of Nω-nitro-l-arginine methyl ester (l-NAME) and l-arginine on lung injury after aortic ischemia–reperfusion (IR).

Methods

Twenty-four Wistar-Albino rats were randomized into four groups (n = 6) as follows: Control (sham laparotomy), Aortic IR (30?min ischemia and 120?min reperfusion), l-Arginine (intraperitoneal 100?mg?kg<συπ>?1 live weight)+aortic IR, and l-NAME (intraperitoneal 10?mg?kg<συπ>?1 live weight)+aortic IR. In the lung specimens, the tissue levels of malondialdehyde (MDA), vascular endothelial growth factor (VEGF), and nitric oxide (NO) were measured and a histological examination was done.

Results

Aortic IR increased MDA, VEGF, and NO. l-Arginine further significantly increased MDA and NO, and decreased VEGF (P < 0.05 vs aortic IR). l-NAME significantly decreased MDA and NO (P < 0.05 vs l-arginine+aortic IR) and increased VEGF (P < 0.05 vs other groups). A histological examination showed the aortic IR to significantly increase (P < 0.05 vs control) while l-arginine also further increased (P > 0.05 vs aortic IR), whereas l-NAME caused a significant decrease in pulmonary leukocyte infiltration (P < 0.05 vs aortic IR).

Conclusions

Our results indicate that l-arginine aggravates the lung injury induced by aortic IR, while l-NAME attenuates it.
  相似文献   
13.
Stepwise rising CO2 insufflation as an ischemic preconditioning method   总被引:2,自引:0,他引:2  
BACKGROUND: The pneumoperitoneum (Pp) is associated with ischemia and reperfusion (I/R) injury and oxidative stress. Various ischemic-preconditioning (IP) methods were used to reduce ischemic injury in intra-abdominal organs. In this experimental, randomized, controlled trial with a blind assessment of the outcome, we evaluated the effects of a new IP method, stepwise rising CO(2) insufflation, on oxidative stress and inflammatory cytokine response. METHODS: Twenty-one rats were divided into three groups. Rats in the control group were subjected to general anesthesia for only 60 minutes. The stepwise group was subjected to 5 mm Hg for 10 minutes, 10 mm Hg for 10 minutes, and 15 mm Hg of CO(2) insufflation for 60 minutes without deflation. In the Pp15 group, the pressure of CO(2) insufflation was fixed at 15 mm Hg for 60 minutes without deflation. Liver and blood samples were examined to determine malondialdehyde (MDA), the antioxidant, superoxide dismutase (SOD), and inflammatory cytokine (tumor necrosis factor-alpha [TNF-alpha], interleukin-6 [IL-6]) levels. Histopathologic scores of liver tissue were examined in all groups. RESULTS: The highest plasma and liver MDA, TNF-alpha, and IL-6 values were in the Pp15 group, followed by the stepwise and control groups. However, plasma and liver SOD levels determined in the control group were significantly higher, compared to stepwise and Pp15 groups. The lowest plasma and liver levels of SOD were in the Pp15 group, followed by the stepwise and control groups. Significantly higher histopathologic scores were found in the Pp15 group, followed by the stepwise and control groups, as well as MDA and inflammatory cytokine (TNF-alpha, IL-6) levels. CONCLUSIONS: We concluded that the stepwise rising CO(2) insufflation method may be an alternative IP method that may lead to a reduction in I/R injury.  相似文献   
14.
Rhabdomyolysis ranges from an asymptomatic illness with elevated creatine kinase levels to a life-threatening condition associated with extreme elevations in creatine kinase, electrolyte imbalances, acute renal failure, and disseminated intravascular coagulation. The most common causes are crush injury, overexertion, alcohol abuse, certain medicines, and toxic substances. A number of electrolyte abnormalities and endocrinopathies, including hypothyroidism, thyrotoxicosis, diabetic ketoacidosis, nonketotic hyperosmolar state, and hyperaldosteronism, cause rhabdomyolysis. Rhabdomyolysis and acute renal failure are unusual manifestations of pheochromocytoma. There are a few case reports with pheochromocytoma presenting rhabdomyolysis and acute renal failure. Herein, we report a case with pheochromocytoma crisis presenting with rhabdomyolysis and acute renal failure.  相似文献   
15.
Many techniques are described for the ligation of a difficult cystic duct (CD). The aim of this study is to assess the effectiveness and safety of stapling of a difficult CD in acute cholecystitis using Endo-GIA. From January 2008 to June 2012, 1441 patients with cholelithiasis underwent laparoscopic cholecystectomy (LC) at the Department of General Surgery, Haydarpasa Numune Education and Research Hospital. Of these, 19 (0.62%) were identified as having a difficult CD and were ligated using an Endo-GIA stapler. All patients were successfully treated with a laparoscopic approach. The length of hospital stay was 3.4 days. There were umbilical wound infections in 4 patients (21%). The length of follow-up ranged from 1.0 to 50.4 months. In conclusion, Endo-GIA is a safe and easy treatment method for patients with a dilated and difficult CD. The cystic artery should be isolated and ligated if possible before firing the Endo-GIA stapler. If isolation and stapling are not possible, fibrin sealant can be applied to avoid bleeding. The vascular Endo-GIA can be applied in a large CD, but for acute cholecystitis with an edematous CD, the Endo-GIA roticulator 4.8 or 3.5 stapler is preferred.Key words: Cholecystectomy, Endo-GIA, Acute cholecystitis, StaplerAfter the introduction of laparoscopic cholecystectomy (LC) in 1987,1 LC replaced open cholecystectomy as the gold standard for the treatment of cholelithiasis in international guidelines.2 LC was initially considered to be contraindicated for acute gallbladder inflammation, but it is currently a common procedure for acute cholecystitis.Some of the difficult situations a surgeon is likely to face during the performance of a laparoscopic cholecystectomy include anatomic anomalies such as a sessile gallbladder or short cystic duct and pathologic entities such as an empyema, Mirizzi syndrome, or a frozen Calot''s triangle secondary to infection and fibrosis.3It is suggested that laparoscopic surgery should be carried out within 72 hours from the onset of the symptoms because after that time there are higher rates of conversion to open procedures, increased risks of complications, and longer operative times.46 The generally accepted procedure in patients whose symptoms started 72 hours before admission is to “cool down” the patient with appropriate medical therapy and to perform LC after a period of 6 to 12 weeks.7,8 This approach aims to avoid a potentially more difficult cholecystectomy during an emergency admission and to avoid the difficulties of access to an emergency room.9,10 However, more than 20% of patients may fail to respond to conservative treatment and require an urgent and rather more difficult cholecystectomy, and a further 25% of patients will require readmission with a severe acute complication of cholelithiasis while awaiting a cholecystectomy.11,12 The scar formation, distortion, and organized adhesions around the gallbladder occurring secondary to the chronic inflammation in Calot''s triangle make the dissection difficult. The cystic duct (CD) is sometimes edematous, fibrous, or enlarged owing to inflammation and adhesions in acute cholecystitis and may be difficult to manage. Several methods were proposed for ligating the CD, including titanium or absorbable endoclip, endoloop, tie, ultrasonic or bipolar sealer, and the Endo-GIA stapler (Covidien, Mansfield, Massachusetts).1319This study proposes an effective, safe, and easy procedure for the stapling of dilated or difficult CD using the Endo-GIA.  相似文献   
16.
AIM: To overview the literature on pancreatic hydatid cyst(PHC) disease, a disease frequently misdiagnosed during preoperative radiologic investigation.METHODS: PubMed, Medline, Google Scholar, and Google databases were searched to identify articles related to PHC using the following keywords: hydatid cyst, hydatid disease, unusual location of hydatid cyst, hydatid cyst and pancreas, pancreatic hydatid cyst, and pancreatic echinococcosis. The search included let-ters to the editor, case reports, review articles, original articles, meeting presentations and abstracts that had been published between January 2010 and April 2014 without any restrictions on language, journal, or country. All articles identified and retrieved which contained adequate information on the study population(including patient age and sex) and disease and treatment related data(such as cyst size, cyst location, and clinical man-agement) were included in the study; articles with in-sufficient demographic and clinical data were excluded. In addition, we evaluated a case of a 48-year-old fe-male patient with PHC who was treated in our clinic.RESULTS: A total of 58 patients, including our one new case,(age range: 4 to 70 years, mean ± SD: 31.4 ± 15.9 years) were included in the analysis. Twenty-nine of the patients were female, and 29 were male. The information about cyst location was available from studies involving 54 patients and indicated the follow-ing distribution of locations: pancreatic head(n = 21), pancreatic tail(n = 18), pancreatic body and tail(n = 8), pancreatic body(n = 5), pancreatic head and body(n = 1), and pancreatic neck(n = 1). Extra-pancreatic locations of hydatid cysts were reported in the studies involving 44 of the patients. Among these, no other focus than pancreas was detected in 32 of the patients(isolated cases) while 12 of the patients had hydatid cysts in extra-pancreatic sites(liver: n = 6, liver + spleen + peritoneum: n = 2, kidney: n = 1, liver + kidney: n = 1, kidney + peritoneum: n = 1 and liver + lung: n = 1). Serological information was available in the studies involving 40 patients, and 21 of those pa-tients were serologically positive and 15 were serologi-cally negative; the remaining 4 patients underwent no serological testing. Information about pancreatic cyst size was available in the studies involving 42 patients; the smallest cyst diameter reported was 26 mm and the largest cyst diameter reported was 180 mm(mean ± SD: 71.3 ± 36.1 mm). Complications were avail-able in the studies of 16 patients and showed the fol-lowing distribution: cystobiliary fistula(n = 4), cysto-pancreatic fistula(n = 4), pancreatitis(n = 6), and portal hypertension(n = 2). Postoperative follow-up data were available in the studies involving 48 patients and postoperative recurrence data in the studies of 51 patients; no cases of recurrence occurred in any patient for an average follow-up duration of 22.5 ± 23.1(range: 2-120) mo. Only two cases were reported as having died on fourth(our new case) and fifteenth days respectively. CONCLUSION: PHC is a parasitic infestation that is rare but can cause serious pancreato-biliary complica-tions. Its preoperative diagnosis is challenging, as its radiologic findings are often mistaken for other cystic lesions of the pancreas.  相似文献   
17.
IntroductionSignificant improvements in patient and graft survival and reductions in the frequency of acute rejection were obtained in the early period after renal transplantation, but this success was not sufficiently reflected in the long term. Allograft kidney losses in the long term remain a significant problem. In this study, we investigated the specific causes of graft losses in patients who had a good clinical course in the first year but developed graft loss in the long term.MethodsA total of 118 patients who underwent kidney transplantation in 2005 and 2006 in the Organ Transplantation Center of Ege University Medical Faculty Hospital were evaluated. The inclusion criteria were to be older than 18 years and have a serum creatinine value of <2 mg/dL at the 12th month after transplantation.ResultsSixty-one percent of the recipients were male, and the mean age at the time of transplantation was 34 ± 11 years (18 to 61). We observed 29 graft losses during the mean follow-up period of 129 ± 35 months (27 to 162). Three of the graft losses were death by functional graft. Of the 26 patients with graft loss, 16 had chronic rejection, and 8 had recurrent glomerulonephritis. The relationship between nonimmune causes and graft loss was not detected.ConclusionsIn conclusion, nonimmune factors may not be as important as we think in relatively young and healthier recipients. Chronic rejection and recurrent glomerulonephritis are the main causes of long-term graft loss of patients with good graft function at the end of the first year. Improvement of long-term survival will be possible with the prevention and effective treatment of these 2 problems.  相似文献   
18.
Background. Sudden death is common in end-stage renal disease (ESRD). Cardiac arrhythmia is observed frequently in patients with ESRD and is thought to be responsible for this high rate of sudden death. This study investigated the prevalence and the predictors of arrhythmia in patients on maintenance dialysis. Methods. Ninety-four patients on hemodialysis program were enrolled in the study. Routine laboratory results were noted. Arrhythmia, periods of silent ischemia, and heart-rate variability analyses were obtained from 24-hour Holter monitor recordings. Corrected QT (QTc) dispersion was calculated from 12-lead surface EKG. Echocardiographic and tissue Doppler examinations were performed on interdialytic days as well. Ventricular arrhythmia was classified according to Lown classification; classes 3 and above were accepted as complex ventricular arrhythmia (CVA). Results. The mean age was 52.5±13.2 years; 44 (46.8%) were women. Ventricular premature contractions were detected in 80 (85.1%) patients, of whom 35 (37.2%) were classified as complex ventricular arrhythmia (CVA). Coronary artery disease, hypertension, and QTc dispersion appeared as independent factors predictive of CVA development. Atrial premature contractions (APC) were detected in 53 patients (56.4%) and supraventricular arrhythmia in 15 (16%) patients; all were identified as atrial fibrillation. Duration of dialysis therapy was found as an independent predictor of APC. Conclusion. Arrhythmia is frequently observed in ESRD patients receiving hemodialysis and may be responsible for the high rate of sudden mortality. Hypertension, CAD, and QTc dispersion are independent predictors of CVA, and duration of dialysis therapy is an independent factor affecting APC development in these patients.  相似文献   
19.
20.

Introduction

Pulse pressure (PP) has been reported as an independent predictor of cardiovascular mortality in hemodialysis patients. In this study, we aimed to investigate association of PP with echocardiographic and vascular structural changes such as atherosclerosis and arterial calcifications in HD patients.

Patients and methods

In this cross-sectional study, 108 chronic hemodialysis patients (49 male, 59 female, mean age: 46?±?13?years) were included. Biochemical analyses, echocardiographic and high-resolution carotid Doppler examinations were done. Aortic wall and coronary artery calcifications were measured with electron beam computed tomography. The degree of carotid artery stenosis was measured at four different sites (communis, bulbus, interna and externa) in both carotid arteries.

Results

PP was strongly correlated with systolic (r: 0.82) and diastolic (r: 0.33) blood pressure, left ventricular mass index (r: 0.58), left ventricle end diastolic diameter (r: 0.38) and weakly correlated with aortic wall calcification score (r: 0.26) and carotid plaque score (r: 0.27), but not with coronary artery calcification score. Patients with carotid plaque had higher PP than patients without plaque (50?±?16?mmHg versus 44?±?14?mmHg, P?=?0.05). Patients were divided into three groups according to aortic wall calcification score. PP was significantly higher in patients with higher aortic wall calcification (54?±?16?mmHg) than patients with lower aortic wall calcification (44?±?15?mmHg, P?=?0.04). However, on multivariate linear regression analysis for predicting PP, the only significant factor retained was left ventricle end diastolic diameter.

Conclusion

PP was weakly associated with large vessel calcification and atherosclerosis in hemodialysis patients. The bulk of the effect on PP seems to be due to hypervolemia.  相似文献   
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