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101.
Osteoarthritis is the most common form of arthritis with still unknown pathogenic etiology and considerable contribution of genetic factors. One of the mechanisms of cartilage degradation in osteoarthritis is enzymatic proteolysis of the extracellular matrix by metalloproteinases. MMP‐1, produced by chondrocytes and synovial cells, is a major proteinase of the MMPs family. The present study aims at evaluating the association of MMP1 gene ‐1607 1G/2G (rs1799750) polymorphism with primary knee osteoarthritis in the Greek population. One hundred fifty five patients with primary symptomatic knee osteoarthritis participated in the study along with 139 controls. Genotypes were determined using PCR—RLFP technique. Allelic and genotypic frequencies were compared between both study groups. There was no significant association between MMP1 ‐1607 1G/2G polymorphism and knee osteoarthritis, in crude analysis; however, after multiple logistic regression analysis, 1G/2G was associated with reduced odds of knee osteoarthritis by 75% in males, compared to genotypes 1G/1G + 2G/2G, adjusting for age and BMI (adjusted OR: 0.25, 95% CI: 0.069, 0.910, p = 0.035). The present study shows that MMP1 ‐1607 1G/2G (rs1799750) polymorphism might be a risk factor for knee osteoarthritis susceptibility in the Greek population. Further investigations are needed to confirm this association in the pathogenesis of osteoarthritis. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1155–1160, 2014.
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102.
The aim of the study is to determine whether dermal scarification is equally effective for treating acute renal colic compared to diclofenac sodium intramuscular therapy. A prospective, randomized controlled study was conducted with methodologic rigor based on CONSORT criteria. A total of 291 patients, aged ≥18 years, suffering from acute renal colic were included in this trial and randomly assigned in two groups. Patients in the first group (A) received endodermal injection (dermal scarification) of 1 ml normal saline at the area of intensity of pain. The second group (B) received 75 mg diclofenac sodium by intramuscular injection. The success of each method defined the primary end point. Pain intensity before and after treatment was assessed using a visual analog scale. The time onset and the duration of analgesia were also recorded. There was no significant difference between the two groups regarding hematuria (p = 0.158), stone identification at KUB (p = 0.751) and mean pain intensity (p = 0.609) before treatment initiation. The method was successful in 75.5 % of patients in group A and 74.3 % of patients in group B (p = 0.812). Mean pain reduction was comparable, 5.65 ± 3.05 in group A and 5.34 ± 2.99 in group B (p = 0.379), with dermal scarification eliciting its effect considerably faster, whereas the duration of analgesia was longer in the diclofenac group (p < 0.05). In conclusion, dermal scarification could constitute an alternative method for treating renal colic as it is equally effective compared to the standard treatment of diclofenac sodium.  相似文献   
103.
The putative involvement of the cerebellum in the pathogenesis of cortical myoclonic syndromes has been long hypothesized, as neuropathological changes in patients with cortical myoclonus have most commonly been found in the cerebellum rather than in the suspected culprit, the primary somatosensory cortex. A model of increased cortical excitability due to loss of cerebellar inhibitory control via cerebello‐thalamo‐cortical connections has been proposed, but evidence remains equivocal. Here, we explore this hypothesis by examining syndromes that present with cortical myoclonus and ataxia. We first describe common clinical characteristics and underlying neuropathology. We critically view information on cerebellar physiology with regard to motorcortical output and compare findings between hypothesized and reported neurophysiological changes in conditions with cortical myoclonus and ataxia. We synthesize knowledge and focus on neurochemical changes in these conditions. Finally, we propose that the combination of alterations in inhibitory neurotransmission and the presence of cerebellar pathology are important elements in the pathogenesis of cortical myoclonus. © 2014 Movement Disorder Society  相似文献   
104.
BackgroundSeveral factors contribute to the manifestation of red blood cell (RBC) storage lesions, with one of the most interesting being the “donor variation effect”. Since many haematological characteristics of blood donors are sex-dependent, sex hormones and their age-dependent variation may affect the storage profile of RBCs.Materials and methodsFresh blood from 200 healthy male and female donors underwent haematological, biochemical and physiological analysis. Three selected groups of donors (men, n=8; pre-menopausal women, n=8; and post-menopausal women, n=4) exhibiting as similar as possible baseline values were recruited for blood donation in leukoreduced CPD/SAGM units. RBC indices, haemolysis and propensity for haemolysis, reactive oxygen species (ROS) and plasma antioxidant capacity were measured bi-weekly.ResultsFemale blood was characterised by lower plasma antioxidant capacity and free haemoglobin (Hb) levels in vivo, in spite of the higher RBC osmotic fragility, compared to male blood. Comparatively low Hb concentration was also measured in stored RBCs from female donors, as in vivo. Mean corpuscular Hb (MCH), mean corpuscular Hb concentration (MCHC), and plasma antioxidant capacity were also lower in female donors throughout storage, even though baseline levels were equal to those of the male group. There was no difference in propensity of stored RBCs for haemolysis between male and female units but intracellular ROS levels were significantly lower in female RBCs. Increased end-of-storage extracellular potassium and recruitment of protein stress markers (clusterin, Hb) to the RBC membrane were observed in the units of post- vs pre-menopausal female donors at mid-storage onwards.DiscussionDonor’s sex has an impact on Hb concentration and redox parameters of stored RBCs. In addition, menopause seems to promote RBC membrane remodelling, at least during prolonged storage. Our pilot study provides new insights on the different effects on RBC storage lesion according to sex.  相似文献   
105.
106.
Violent incidents in acute inpatient units for children and adolescents are a major and persistent problem. The demographic, clinical, and modifiable (environmental–organizational) risk factors that affect inpatient violence in an Acute Child and Adolescent Psychiatric Unit were investigated via a retrospective study. Data were collected from nursing and medical reports and the unit's census and included 100 days per year for 16 years. Incidents of violence and assault types were recorded, and variables such as the diagnostic category of assailants, total number of patients, and staffing factors during the incident were examined. Of the 2390 violent incidents recorded, 50% were attributed to cases of physical violence towards another patient, 17% to physical violence towards nursing staff, 19% to physical violence towards self and 14% to destruction of property. According to the final multivariable model, for each additional patient in the unit, the risk of a violent event increased by 9.51%; for each additional offender patient, the risk increased by 14.06%; the number of assistant nurses was associated with a 25.03% increased risk; and, after 2006, the risk increased by 68.99%. The most significant factor associated with a 59.98% decreased risk was the total number of nursing staff. All variables significantly and independently contributed to the model. Acute inpatient psychiatric units with a small number of hospitalized patients, adequate, well‐trained and specialized nursing staff, and the hospitalization of different types of patients in separate wards or units are expected to facilitate a reduction in the frequency of violent incidents.  相似文献   
107.
BACKGROUND/AIMS: The aim of this study was to investigate patients who underwent endoscopic sphincterotomy for "acalculus" cholangitis associated with juxtapapillary diverticula. METHODOLOGY: In a retrospective study we analyzed 87 patients who underwent endoscopic sphincterotomy for cholangitis; the cholangitis considered "acalculus", when outlining the extra- and intrahepatic bile ducts, we could not observe any intraluminal defect or stricture, and during the clearing of the bile ducts with the balloon, after endoscopic sphincterotomy, there was no evidence of stones, fragments of stones or sludge. Patients who had undergone previous endoscopic sphincterotomy, or who had additional pancreatobiliary diseases were excluded from this study. There were 11 patients with "acalculus" cholangitis associated with juxtapapillary diverticula, and sufficient clinical data available for this study. RESULTS: Nine patients presented pain, fever, and jaundice. In two patients diagnosis was established via the test of abnormal liver biochemistry. Seven patients had positive blood cultures and three of them developed confusion and hypotension. Endoscopic sphincterotomy succeeded in all cases; no evidence of stones, fragments of stones or sludge was recorded during the clearing of bile ducts, after endoscopic sphincterotomy, with the balloon. Five patients presented mild post-endoscopic sphincterotomy complications successfully treated. In the follow-up period, from 4 months to 7 years after endoscopic sphincterotomy, none of the patients developed symptoms of cholangitis. CONCLUSIONS: We recommend endoscopic sphincterotomy in patients with "acalculus" cholangitis associated with juxtapapillary diverticula, despite the absence of obvious obstruction, and the possible morbidity which is inherent with an invasive procedure like endoscopic sphincterotomy.  相似文献   
108.
BACKGROUND: Tea consumption is associated with decreased cardiovascular risk. Flow-mediated dilatation (FMD) of the brachial artery is related to coronary endothelial function and it is an independent predictor of cardiovascular risk. Black tea has a beneficial effect on endothelial function; the effect, however, of green tea on brachial artery reactivity has not been defined yet. DESIGN AND METHODS: We studied 14 healthy individuals (age 30+/-3 years) with no cardiovascular risk factors except from smoking (50%) on three separate occasions on which they took: (a) 6 g of green tea, (b) 125 mg of caffeine (the amount contained in 6 g of tea), or (c) hot water. FMD of the brachial artery was measured before each intervention and 30, 90, and 120 min afterward. High-sensitivity C-reactive protein, interleukins 6 (Il-6) and 1b (Il-1b), total plasma antioxidative capacity, and total plasma oxidative status/stress were measured at baseline and at 120 min after each intervention. RESULTS: Resting and hyperemic brachial artery diameter did not change either with tea or with caffeine. FMD increased significantly with tea (by 3.69%, peak at 30 min, P<0.02), whereas it did not change significantly with caffeine (increase by 1.72%, peak at 30 min, P=NS). Neither tea nor caffeine had any effect on high-sensitivity C-reactive protein, Il-6, Il-1b, total plasma antioxidative capacity, or total plasma oxidative status/stress. CONCLUSION: Green tea consumption has an acute beneficial effect on endothelial function, assessed with FMD of the brachial artery, in healthy individuals. This may be involved in the beneficial effect of tea on cardiovascular risk.  相似文献   
109.
BACKGROUND/AIMS: Permanent portal vein embolization (PVE) is a widely practised technique. The use of an absorbable material would be safer in clinical situations in which the embolized liver is not resected. We evaluated the efficiency of reversible PVE in terms of liver regeneration and analyzed the precise time course of portal recanalization. METHODS: Nine monkeys underwent PVE of the left and right anterior portal branches using powdered absorbable material. Repeated portograms were carried out until complete revascularization of the embolized liver. Hepatocyte proliferation rates were assessed by BrdU incorporation. Liver segment volumes were determined by CT scans performed before embolization, then 1month and 1year after embolization. RESULTS: Reversible PVE induced significant hepatocyte proliferation in the non-embolized segments (13.5+/-1.0%, 10.5+/-0.8% and 9.1+/-2.0% of cells on days 3, 5 and 7, respectively). One month after the embolization, the non-embolized liver volume had increased from 38.4+/-1.3% to 54.8+/-0.5% of total liver volume. Proximal and complete revascularization occurred 6-8 and 12-16days, respectively. CONCLUSIONS: Reversible PVE efficiently induces liver regeneration. The use of absorbable material avoids long-term liver scarring. Such material may be suitable for several clinical indications, including cell transplantation.  相似文献   
110.
There is a subgroup of patients with achalasia in which manometry shows elevated intraesophageal pressure, expressed by elevation of esophageal baseline relative to gastric pressure. The aim of this study was to determine the prevalence of elevated intraesophageal pressure in patients with achalasia and its relationship to clinical, radiographic, endoscopic, and other manometric findings. Manometric studies of 62 patients with achalasia were analyzed and elevated intraesophageal pressure was considered any positive elevation of esophageal baseline relative to gastric pressure. Multiple regression analysis was used to determine independent risk factors associated with elevated intraesophageal pressure. Elevated intraesophageal pressure was found in 32 patients (51.6%). Lower esophageal sphincter pressure was the only independent variable associated with elevated intraesophageal pressure (P = 0.0167). Mean lower esophageal sphincter pressure was significantly higher in patients with elevated compared to those with normal intraesophageal pressure (34 +/- 1.96 vs 26.5 +/- 1.73 mm Hg; P = 0.006). In addition, lower esophageal sphincter pressure had a positive correlation with intraesophageal pressure (r = 0.49, P < 0.001). Conversely, no correlation was found between elevated intraesophageal pressure and various symptoms, disease duration, radiologic dilation, a finding of retained fluid during endoscopy, and esophageal length. We conclude that elevated intraesophageal pressure is a common manometric finding in patients with achalasia, with a prevalence of 51.6%, and is associated with significantly higher lower esophageal sphincter pressure.  相似文献   
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