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61.
A plasma factor displaying permeability activity in vitro and possibly determining proteinuria has been hypothesized in idiopathic focal segmental glomerulosclerosis (FSGS). In vitro permeability activity (P(alb)) was determined in sera of five patients with autosomal recessive steroid-resistant nephrotic syndrome (NPHS2), an inherited condition indistinguishable from idiopathic FSGS on clinical grounds, but in which proteinuria is determined by homozygous mutations of podocin, a key component of the glomerular podocyte. All patients had presented intractable proteinuria with nephrotic syndrome; four developed renal failure and received a renal allograft. For comparison, sera from 31 children with nephrotic syndrome were tested. Pretransplant P(alb) was high in all cases (mean 0.81 +/- 0.06), equivalent to levels observed in idiopathic FSGS. Overall, P(alb) did not correlate with proteinuria. The posttransplant outcome was complicated in two patients by recurrence of proteinuria after 10 and 300 d, respectively, that responded to plasmapheresis plus cyclophosphamide. P(alb) levels were high at the time of the recurrence episodes and steadily decreased after plasmapheresis, to reach normal levels in the absence of proteinuria after the seventh cycle. In an attempt to explain high P(alb) in these patients, putative inhibitors of the permeability activity were studied. Coincubation of serum with homologous nephrotic urine reduced P(alb) to 0, whereas normal urine did not determine any change, which suggests loss of inhibitory substances in nephrotic urine. The urinary levels of the serum P(alb) inhibitors apo J and apo E were negligible in all cases, thus suggesting that other urinary inhibitors were responsible for the neutralizing effect. These data indicate that P(alb) is high in NPHS2, probably resulting from loss of inhibitors in urine. Lack of correlation of P(alb) with proteinuria suggests a selective loss of inhibitors. As in idiopathic FSGS, proteinuria may also recur after renal transplantation in NPHS2 patients, and post-transplant proteinuria is associated with high P(alb). The relationship between elevated P(alb) and proteinuria in NPHS2 remains to be determined.  相似文献   
62.
Because of the role of serotonin (5HT) in regulating food intake and mood, several studies have focused their attention on the assessment of serotonergic activity in eating disorders, and in particular in anorexia nervosa, but the results have been inconsistent. Citalopram, a highly selective 5HT reuptake inhibitor, has been recently reported as a neuroendocrine probe to assess the serotonergic function in physiological and pathological conditions. We evaluated the adrenocorticotropic hormone (ACTH), cortisol, prolactin (PRL) and growth hormone (GH) secretion during placebo or citalopram IV infusion (20 mg over 120 min), in six women with anorexia nervosa restricter type, and in six healthy women, in order to test the hypothesis that this neurotransmitter system is abnormal in this group of patients. ACTH and PRL secretion was higher during citalopram infusion compared to placebo (p<0.05) in both groups, while cortisol secretion was higher during citalopram infusion only in healthy controls (p<0.05), but not in anorexic patients. GH levels were unaffected by citalopram in both groups. These results demonstrate that serotonergic activation by citalopram affects corticotroph and lactotroph but not somatotroph secretion in anorexic as well as in normal subjects. Our preliminary findings do not support the existence of remarkable alterations in the serotonergic control of anterior pituitary function in anorexia nervosa, while there seems to be an impairment of the adrenal function in this group of patients.  相似文献   
63.
Congenital vascular malformations represent a wide number of diseases with a great variability of clinical features. The association between congenital vascular malformations and peripheral aneurysms is very rare. The present study reports a case of giant superficial femoral artery aneurysm (7-cm-long) associated with Parkes-Weber syndrome (capillary malformation, multiple arteriovenous fistulas [AVFs], skeletal hypertrophy of the affected limb) treated by positioning two covered self-expandable endoprostheses after embolization of AVFs with Gianturco coils. The peri- and postoperative course was uneventful and the postprocedural angiography showed the complete exclusion of the aneurysm sac. At last follow-up, after 87 months, the duplex scan and computed tomography scan showed regular patency of the vessels with thrombosis of the aneurysm sac and the presence of a large number of AVFs. The association between Parkes-Weber syndrome and peripheral aneurysms represents a very unusual entity. The lack of evidence does not allow the establishment of the most suitable treatment for this disease. Endovascular approach associated with previous embolization of AVFs may represent a valid alternative to traditional surgical repair, which is still burdened by a high percentage of complications and failures.  相似文献   
64.
In patients with systemic lupus erythematosus, involvement of the cardiovascular system is the third leading cause of death. However, although autopsy studies have demonstrated a high incidence of abnormalities in both the myocardium and coronary vessels, clinical manifestations have been reported in only a small percentage of cases. The aim of this study was to evaluate myocardial perfusion in asymptomatic lupus patients using technetium-99m sestamibi single-photon emission tomography (SPET). Twenty-eight patients without overt cardiac involvement and risk factors were studied with 99mTc-sestamibi SPET at rest and after dipyridamole infusion. Perfusion abnormalities were detected in 18 cases: six had persistent defects, three had reversible defects, seven had both persistent and reversible defects, and two showed rest defects which normalized on dipyridamole images (”reverse redistribution pattern”). Coronary angiography was performed in eight patients with positive 99mTc-sestamibi SPET, and showed normal epicardial vessels in all the cases. These results indicate that 99mTc-sestamibi SPET reveals a high prevalence (18 out of 28 patients in this study, i.e. 64%) of myocardial perfusion abnormalities in asymptomatic lupus patients, probably due to the primary immunological damage of this autoimmune disease. In conclusion, rest/dipyridamole 99mTc-sestamibi SPET can be a useful non-invasive method to identify subclinical myocardial involvement in systemic lupus erythematosus, and patients potentially at risk of later cardiac events. Received 20 November 1998 and in revised form 19 February 1999  相似文献   
65.
Since May 2002 all groups performing hand transplantations have supplied detailed information to the International Registry on Hand and Composite Tissue Transplantation. This report provides a review of all hand transplants performed to date. From September 1998 to February 2006 eighteen male patients underwent 24 hand/forearm/digit transplantations (eleven unilateral and four bilateral hand transplantations, two bilateral forearm transplantations, one thumb transplantation). The level of amputation was mostly at the distal forearm or wrist. Patient average age was 32. Time since hand loss ranged from 2 months to 22 years. Immunosuppressive therapy included tacrolimus, mycophenolate mofetil, rapamycin and steroids; polyclonal or monoclonal antibodies were used for induction. Topical immunosuppression was administered in some patients. Follow-up period ranged from 34 to 85 months. Patient survival was 100%. Graft survival was 100% at 1 and 2 years. Two cases of graft failure at a later date occurred and were caused by severe inflammation and progressive rejection in a non-compliant patient. In addition, 6 hands were lost due to a rejection process as the Chinese recipients did not take their immunosuppressive treatment. These failures were communicated in January 2006. Acute rejection episodes occurred in 12 patients within the first year. Rejection was completely reversible in all compliant patients. Side-effects included opportunistic infections and metabolic complications. No life-threatening complications or malignancies were reported. As it would have been very difficult to analyse transplantation functional results in a standardized way, the Registry has performed a functional score system. All patients had achieved protective sensation and in 17 of them also discriminative sensation. Extrinsic and intrinsic muscle recovery enabled patients to perform most daily activities and 90% of the recipients returned to work, and improved manual skills allowed them not only to resume their previous jobs but also, in some cases, to find more suitable employment. Fifteen recipients reported an improvement of their quality of life and we evaluated as a very important point as patient satisfaction and well-being are mandatory goals of hand transplantation.  相似文献   
66.
This study was aimed at identifying predictive variables for recurrence of mitral regurgitation (MR) in patients with dilated cardiomyopathy (DCM) undergoing mitral valve (MV) repair. From January 1997 to December 2005, 142 patients with DCM, 105 (73.9%) ischemic and 37 (26.1%) non-ischemic, underwent MV repair. Mean age was 66+/-10 years and mean MR grade was 3.2+/-0.7 (scale 1+ to 4+). Ninety-seven (71% ischemic, 29% non-ischemic), out of 98 still alive at follow-up, were included in this retrospective analysis. In all cases MV posterior annuloplasty was performed; all patients were followed-up by echocardiography (mean time interval of 44+/-28 months) to evaluate MR recurrence (>or=2+/4+). Thirty-day mortality was 9.2% (13 patients). Mean MR grade at follow-up was 0.9+/-0.9. Four-year freedom from MR recurrence was 65.5%+/-8.3. Cox analysis showed left ventricular end-diastolic volume index (LVEDVi, OR=1.03, P=0.016, AUC=0.72), left ventricular end-systolic volume index (LVESVi, OR=1.03, P=0.033, AUC=0.71), left ventricular ejection fraction (LVEF, OR=0.82, P=0.001, AUC=0.72), mitral valve coaptation depth (MVCD, OR=1.6, P=0.017, AUC=0.72) to be predictive variables for MR recurrence. Preoperative left ventricular dilatation and function along with degree of papillary muscle displacement can be helpful in identifying patients with higher probability to undergo a durable MV repair.  相似文献   
67.
Risk factors for renal scarring in children with lower urinary tract dysfunction (LUTD) were evaluated. The medical records of 120 patients were assessed concerning gender, presence of vesicoureteric reflux (VUR), bladder capacity, detrusor overactivity, residual urine, febrile urinary tract infection (UTI), bacteriuria, constipation, detrusor sphincter incoordination (DSI), high detrusor pressure at maximal cystometric capacity (PMCC), low compliance, and thickness and trabeculation of the bladder wall. Renal scarring was diagnosed by 99mtechnetium-dimercaptosuccinic acid renal scan (DMSA). Renal scarring was detected in 38 patients (31%). VUR, UTI, decreased bladder capacity, urinary residue, and trabeculated and thick bladder wall were associated with scarring at univariate analysis. Multivariate analysis showed VUR (P < 0.0001) as the independent risk factor for renal scarring. Thickness of the bladder wall was a marginal risk factor (P= 0.07). Although UTI was not a risk factor, it was associated with VUR (P= 0.03). In our analysis, VUR was the main risk factor; however, renal scarring was probably due to multifactorial causes, as VUR was associated with UTI.  相似文献   
68.
BACKGROUND: The inflammatory cascade has been hypothesized to be an important mechanism of post-ischaemic myocardial reperfusion injury and several studies demonstrated that C1 esterase inhibitor (C1-INH) is effective in post-ischaemia myocardial protection. Therefore, we aimed to investigate prospectively in a randomised double-blind study the cardioprotective effects of C1-INH in ST segment elevation myocardial infarction (STEMI) in patients who underwent emergent reperfusion with coronary artery bypass grafting (CABG). METHODS: In this study, we enrolled 80 patients affected with STEMI who underwent emergent CABG. Patients were assigned in two groups (C1-INH group: receive 1000 UI of C1-INH; and placebo group: receive a saline solution). The effects of C1-INH on complement inhibition, myocardial cell injury extension and clinical outcome were studied. Haemodynamic data and myocardial function were monitored. C1-INH, C3a, C4a complement activation fragments and cardiac troponin I (cTnI) serum levels were measured before, during and after surgery. RESULTS: Patient characteristics were not different between the two groups. The overall in-hospital mortality rate was 6.2%. No statistical significant difference was observed between the two groups with regard to early mortality (p=0.36). Statistical significant difference between the two groups was showed for cardiopulmonary bypass support (p=0.04), administration of high dose of inotropes drugs (p=0.001), time of intubation (p=0.03), intensive care unit (ICU) stay (p=0.04) and in-hospital stay (p=0.03). A significant improvement in mean arterial pressure (p=0.03), cardiac index (p=0.02) and stroke volume (p=0.03) was showed in C1-INH group versus placebo group. The serum cTnI levels were significantly low in the C1-INH group versus placebo group after reperfusion, during the observation period. Plasma levels of C3a and C4a complement fragments were reduced significantly in C1-INH group. No drugs-related adverse effects were observed. CONCLUSIONS: The inhibition of the classic complement pathway by C1-INH appears to be an effective mean of preserving ischaemic myocardium from reperfusion injury as demonstrated by low serum cTnI levels in C1-INH group. Therefore, the use of C1-INH during CABG as a rescue therapy in STEMI patients is probably an effective treatment to inhibit complement activity and to improve cardiac function and haemodynamic performance without impacting early mortality. Large randomised study should be performed to support our results.  相似文献   
69.
BACKGROUND: Oral premedication is widely used in pediatric anesthesia to reduce preoperative anxiety and ensure smooth induction. Midazolam is currently the most commonly used premedicant, but good results have also been reported with clonidine. The aim of the present study was to compare clinical effects of oral midazolam and oral clonidine. METHODS: We performed a prospective open study in 64 children who were randomly assigned to receive either oral midazolam 0.5 mg.kg (-1) (group M) or oral clonidine 4 microg.kg (-1) (group C) prior to mask induction. Drug acceptance, preoperative sedation and anxiolysis, quality of mask acceptance, recovery profile and parental satisfaction were evaluated. RESULTS: The taste of oral clonidine was judged as significantly better; 14% of children rejected oral midazolam. Onset of sedation was significantly faster after premedication with midazolam (30+/-13.1 min) than with clonidine (38.5+/-14.6 min), but level of sedation was significantly better after premedication with clonidine. Quality of mask induction was equally successful in both groups. A steal-induction was performed in 66% of patients of group C, but none in group M. We observed a trend towards an increased incidence of emergence agitation after premedication with midazolam. Parental satisfaction was significantly higher in group C. CONCLUSIONS: In this study, premedication with oral clonidine appeared to be superior to oral midazolam. Quality of mask acceptance was comparable between groups, but oral clonidine was better accepted by the child, produced more effective preoperative sedation, showed a trend towards better recovery from anesthesia and had a higher degree of parental satisfaction.  相似文献   
70.
Obesity is linked to the development of cancer. Previous studies have suggested that there is a relationship between bariatric surgery and reduced cancer risk. Data sources were from Medline, Embase, and Cochrane Library. From 951 references, 13 studies met the inclusion criteria (54,257 participants). In controlled studies, bariatric surgery was associated with a reduction in the risk of cancer. The cancer incidence density rate was 1.06 cases per 1000 person-years within the surgery groups. In the meta-regression, we found an inverse relationship between the presurgical body mass index and cancer incidence after surgery (beta coefficient ?0.2, P?相似文献   
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