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1.
Writer's cramp is a task-specific dystonia that leads to involuntary hand postures during writing. Abnormalities of sensory processing may play a pathophysiological role in this disorder. Electrophysiology studies in a monkey model of focal dystonia have revealed de-differentiation of sensory maps and the existence of single cells in hand regions of area 3b with enlarged receptive fields that extend to the surfaces of more than one digit. These changes may lead to abnormal processing of simultaneous sensory inputs. To study abnormal processing of simultaneous sensory information in adult humans with writer's cramp, we used functional magnetic resonance imaging to compare the response in primary sensory cortex with simultaneous tactile stimulation of the index and middle finger, with the response to stimulation of each finger alone. We tested five patients with writer's cramp and seven unaffected (normal) subjects. In the normal subjects, a linear combination of the activation patterns for individual finger stimulation predicts the pattern of activity for combined stimulation with 12% error. In writer's cramp patients, the linear combination predicted the combined stimulation pattern with 30% error. Results indicate a nonlinear interaction between the sensory cortical response to individual finger stimulation in writer's cramp. This altered interaction may contribute to the motor abnormalities.  相似文献   
2.
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction.  相似文献   
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4.
Summary In a cross-sectional study of 181 male workers of a rotogravure printing plant, most of whom were exposed to toluene levels well above the GDR threshold limit values, 55 subjects revealed pathological liver screening values (activities of serum aspartate aminotransferase, alanine amino-transferase, gamma glutamyltransferase; liver size). The differential diagnostic examination showed in 51 out of these 55 subjects an association with competing factors such as alcohol abuse (78%) and overweight (40%), to a slight extent disorders of fat and carbohydrate metabolism and of the gallbladder. Drug intake did not play any role. The variance and regression analyses of the biochemical data have shown that alcohol significantly and considerably increases the activities of all three enzymes tested. Bodyweight had a similar, but less pronounced, significant effect. On the other hand, in subjects with a higher alcohol intake the activities of liver enzymes in highly toluene exposed subgroups were significantly and clearly lower than among slightly toluene exposed workers.  相似文献   
5.
Background: Percutaneous cricothyroidotomy is a lifesaving procedure for airway obstruction in trauma victims who need airway establishment and cannot be intubated or in whom intubation has failed.

Methods: The purpose of this study was to examine whether there is a training effect using Seldinger technique emergency cricothyroidotomy (group 1; Arndt Emergency Cricothyroidotomy Catheter Set; Cook Critical Care, Bloomington, IN) versus standard surgical cricothyroidotomy (group 2). Twenty emergency physicians performed five cricothyroidotomies with each method in a total of 200 human cadavers, comparing efficacy and safety (speed, success rate, and injuries).

Results: Seven attempts in group 1 and six in group 2 had to be aborted. Time intervals from the start of the procedure to location of the cricothyroid membrane were not significantly different between the groups. However, time to tracheal puncture (P < 0.01) and time to first ventilation (P < 0.001) were significantly longer in group 2. No time effect could be observed in both groups. The airway was accurately placed into the trachea through the cricothyroid membrane in 88.2% (82 of 93) of the cadavers in group 1 and in 84.0% (79 of 94) in group 2 (not significant). No injuries were observed in group 1, whereas there were six punctures of the thyroid vessels in group 2 (P < 0.05).  相似文献   

6.
The deep inferior epigastric perforator (DIEP)-flap continues to be the standard treatment in microsurgical breast reconstruction. Reasons for the popularity of the DIEP-flap include the availability of a large amount of tissue for the reconstruction of large breasts, a reliable vascular anatomy and an aesthetically pleasing donor site scar. However, the DIEP-flap is not considered the optimal choice as the donor tissue in all patients. Previous abdominal surgeries with resulting scars may threaten the success of a free DIEP-flap due to compromised vascularity within the flap. We elaborated a technique to increase the safety of breast reconstruction with the DIEP-flap in the presence of an infraumbilical vertical scar. After raising the DIEP-flap in a traditional manner on one side with harvesting of a considerate length of the inferior epigastric vessels, a segment of the superior epigastric vessels is left attached to the main pedicle. This stump of the superior epigastric vessels is now anastomosed under the microscope to a paraumbilical perforator on the contralateral side of the flap for in-flap microvascular augmentation. The above-mentioned technique was applied in five patients who presented with an infraumbilical vertical scar and were reconstructed with a DIEP-flap because of breast cancer. In three of the five patients there was an additional risk factor present such as smoking or diabetes mellitus. In all five patients no major complication due to marginal perfusion of the contralateral side of the flap was encountered. In two patients there was minor breakdown of fatty tissue that was managed conservatively in both cases. In-flap microvascular augmentation of DIEP-flaps is a valuable tool for the plastic surgeon in microvascular breast reconstruction. It permits usage of the lower abdominal tissue even if perfusion is compromised due to midline scarring. We recommend this technique as a safe alternative in patients seeking autologous breast reconstruction in the presence of a midline abdominal scar.  相似文献   
7.
PURPOSE: Amiodarone (AMIO), a widely used anti-arrhythmic drug, has been shown to reduce the incidence of atrial fibrillation after cardiac surgery and also to exert immunomodulatory actions in vitro and proinflammatory effects in vivo. The present study investigated the immunomodulatory properties of AMIO in the inflammatory response induced by cardiac surgery with cardiopulmonary bypass (CPB). METHODS: In this double-blind, placebo-controlled trial, 20 patients undergoing elective coronary artery bypass graft were randomized to receive placebo or AMIO 600 mg day(-1) orally for seven days before surgery and 45 mg hr(-1) intravenously for 48 hr postoperatively. Plasma levels of the proinflammatory markers C-reactive protein (CRP), fibrinogen (FBG), tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1, and the antiinflammatory marker IL-10, were compared before and after surgery. RESULTS: Ninety-six hours after start of surgery, plasma levels of FBG had more than doubled (2.2 +/- 0.5-fold increase, P < 0.0001). Overall, FBG formation was significantly increased in the AMIO group (P = 0.048). Monocyte chemoattractant protein 1 secretion transiently increased four hours after start of surgery (6.6 +/- 4.5-fold increase) but rapidly declined thereafter, (P < 0.0001). There was a trend toward higher MCP-1 plasma concentrations in the AMIO group (P = 0.13). The plasma levels of CRP, TNF-alpha, IL-6 and Il-10 changed significantly over time, but were not altered by AMIO treatment. CONCLUSION: In the inflammatory response induced by cardiac surgery with CPB, our data suggest that AMIO treatment is associated with a selective trend toward proinflammatory actions.  相似文献   
8.
The chick chorioallantoic membrane (CAM) model was used to study vascular effects of photodynamic therapy (PDT) and hyperthermia (HPT) and the synergism of these modalities. The CAM is a convenient medium for monitoring the modifications of the vasculature. It is possible to view the CAM and to examine structural changes of individual blood vessels in real time. Moreover, the CAM is a closed system which lends itself to mathematical modeling of the temporal and spatial temperature profile and in which HPT can be performed quantitatively and to a selected depth, using different lasers. A porphyrin-type photosensitizer solution was applied to areas of the CAM, defined by teflon O-rings placed on the surface. Uptake dynamics of the sensitizer into the CAM was determined by analyzing its fluorescence in vivo. The CAM area was irradiated with a dual-wavelength laser system composed of a dye laser at 644 nm (to induce PDT) and a CO2 laser at 10.6 microns (to bring about HPT). Damage to the CAM vasculature, due to combined PDT+HPT, was compared to the outcome of the separate modalities, and a synergistic effect of about 40% was observed.  相似文献   
9.
In premature neonates a patent ductus arteriosus causes often other complications thus the immediate closure of the patent ductus arteriosus should be preferred or recommended. Performing the surgical closure of the ductus within the incubator can avoid complications during transportation from the premature neonates intensive care unit to the operating room. 25 very small premature neonates or those with another burden in addition were operated upon in the incubator on the premature infants intensive care unit of our hospital during the period from January 1987 to April 1989. No complications occurred during the operation, especially not caused by the strange circumstances for the operating team. Wound infections because of possible bacterial contamination of the incubator or the room were not observed during the postoperative period.  相似文献   
10.
In six patients with doxorubicin-related cardiotoxicity, the severity of decrease in left ventricle ejection fraction (LVEF) was associated with faster myocardial I-123 MIBG washout rates. In four patients with severely decreased LVEF (range 19% to 28%), the 4-hour washout rate varied from 43% to 56%. In two patients with moderate cardiotoxicity (LVEF 42% and 43%), the washout rates were 37% and 35%, respectively. In contrast, in another patient thought to have initial left ventricular dysfunction (LVEF dropped from 66% to 54%), the myocardial I-123 MIBG retention rate was not reduced (6% washout). Subsequent continuation of chemotherapy in this patient was without complication. Reduced I-123 MIBG uptake in the left ventricle generally correlated with areas with abnormal Fourier amplitude values, but in one of the patients with moderate cardiotoxicity, the I-123 MIBG uptake was not reduced in a region with loss of amplitude, indicating dysfunction but probably no myocardial denervation. Analysis of the regional myocardial retention in patients with cardiotoxicity showed no significant difference in the I-123 MIBG washout rates of both segments with or without loss of amplitude. These data suggest that in spite of a localized loss of ventricular function demonstrated by radionuclide angiocardiography, doxorubicin-related cardiotoxicity appears to be based on a global process of myocardial adrenergic derangement.  相似文献   
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