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81.
A girl aged 2 years and 8 months came to our clinic for consultation with regard to unerupted primary mandibular bilateral central incisors. An intraoral examination revealed that the teeth had not emerged into the oral cavity and showed a tooth crown morphology similar to that of the primary mandibular incisors, which appeared in the lingual submucosal area outside of the mandibular dental arch. Periapical radiographs demonstrated that the tooth crowns of both affected teeth were severely displaced to the lingual side. Computed tomography examinations were performed to clarify the three-dimensional positions of the affected teeth and their permanent successors, which revealed that the affected teeth were located in their estimated positions and had a standard root morphology. In addition, the permanent successors, which had not initiated root formation, were located close to the affected teeth. We decided to postpone extraction of the affected teeth and perform periodical examinations until the roots of the permanent successors are sufficiently formed. At the age of 2 years and 10 months, the edge of the tooth crown of the primary mandibular left central incisor was found emerged into the oral cavity. According to her parents, the patient did not complain of the emerging edge and no abnormal conditions were observed around the tooth.  相似文献   
82.
Politicians often deplore economic agents’ behaviour when they do not accept new technologies. For a new technology to be adopted, the new technology value function needs to dominate the old technology value function. If this is the case, a technology switch will occur. We characterise the value functions, without computing them, using the fact that their hypographs are viability kernels of some auxiliary control problems and study whether the graphs intersect. If they do not, the corresponding value functions do not dominate each other, and the switch cannot occur at a positive time. Using this characterisation, we analyse a technology adoption problem and show how to recognise the models, for which the switch will occur at time zero or never, without solving an optimal control problem. We conclude that the current control regime may not change if the economic agents’ preferences are modelled as an integral of discounted differences between a reward from the flow variable (control) and a penalty from the stock variable (state).Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
83.
Vasodepressor Cough Syncope. Cough syncope is classified among the neural-reflex "situational" faints, but whether the clinical consequences in affected individuals result from reflex triggered bradyarrhythmia or vasodepressor-induced hypotension, or both, is often unknown. In this report we describe findings in a patient with a clinical history consistent with cough syncope, and in whom documented multiple asystolic spells were at first believed to be responsible for symptoms. However, pacemaker therapy initiated at an outside facility failed to suppress symptoms, and subsequent referral for more detailed autonomic study revealed the asystole to be due to sleep apnea, whereas cough-induced vasodepressor hypotension was the basis of syncope in this individual; the latter provided a pathophysiologic target for prevention of recurring symptoms. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1024-1027, September 2012).  相似文献   
84.
Aim: The factors associated with hepatitis recurrence after discontinuation of nucleos(t)ide analogs (NAs) in patients with chronic hepatitis B were analyzed to predict the risk of relapse more accurately. Methods: A total of 126 patients who discontinued NA therapy were recruited retrospectively. The clinical conditions of a successful discontinuation were set as alanine aminotransferase (ALT) below 30 IU/L and serum hepatitis B virus (HBV) DNA below 4.0 log copies/mL. Results: Relapse of hepatitis B were judged to occur when maximal serum ALT became higher than 79 IU/L or when maximal serum HBV DNA surpassed 5.7 log copies/mL following NA discontinuation since these values corresponded with mean values of ALT (30 IU/L) and HBV DNA (4.0 log copies/mL), respectively. At least 90% of patients with either detectable hepatitis B e antigen or serum HBV DNA higher than 3.0 log copies/mL at the time of NA discontinuation relapsed within one year. In the remaining patients, higher levels of both hepatitis B surface and core‐related antigens at the time of discontinuation, as well as a shorter course of NA treatment, were significantly associated with relapse by multivariate analysis. Conclusions: It appears that negative results for hepatitis B e antigen and serum HBV DNA lower than 3.0 log copies/mL are essential for successful NA discontinuation, which may be attained by a longer treatment period. Levels of hepatitis B surface and core‐related antigens are also significant factors independently associated with relapse of hepatitis.  相似文献   
85.
Objectives: The aim of the present study was to evaluate whether a complex course obstacle negotiation exercise (CC), a 24‐week exercise program, can reduce falls and fractures in older adults, as compared with a simple course obstacle negotiation exercise (SC). Methods: This trial was carried out on older adults, aged 75 years and above in Japan. In total, 157 participants were randomized into the CC group (n = 78) and the SC group (n = 79). Participants were enrolled in the exercise class using the CC program or the SC program for 24 weeks. The outcome measure was the number of falls and fracture rates in CC and SC groups for 12 months after the completion of the 24‐week exercise class. Results: Two participants (2.8%) in the CC group and 19 (26.0%) in the SC group experienced falls during 12 months. During the 12‐month follow‐up period after the intervention, the incidence rate ratio (IRR) of falls in the SC group against the CC group was 9.37 (95% CI = 2.26–38.77). One participant (1.4%) in the CC group and eight (10.9%) in the SC group had experienced fractures during 12 months after the exercise class. The IRR of fractures in the SC group compared with the CC group was 7.89 (95% CI = 1.01–61.49). Conclusions: The results of the present trial show that the participants who received individualized obstacle avoidance training under complex tasks combined with a traditional intervention had a lower incidence rate of falls and fractures during the 12 months after the intervention. Geriatr Gerontol Int 2012; 12: 461–467.  相似文献   
86.
Tick-borne diseases are of great concern worldwide. Despite this, in Romania there is only limited information regarding the prevalence of vector-borne pathogens in dogs. In all, 1146 serum samples were tested by SNAP(?) 4Dx(?) (IDEXX Laboratories, Inc., Westbrook, ME) for Anaplasma phagocytophilum, Borrelia burgdorferi, and Ehrlichia canis antibodies, and for Dirofilaria immitis antigen. The correlation between positive cases and their geographic distribution, as well as potential risk factors (age, sex, breed, type of dog, habitat, and prophylactic treatments) were evaluated. Overall, 129 dogs (11.3%) were serologically-positive to one or more of the tested pathogens. The seroprevalence for the four infectious agents were: A. phagocytophilum 5.5% (63/1146), D. immitis 3.3% (38/1146), E. canis 2.1% (24/1146), and B. burgdorferi 0.5% (6/1146). Co-infection with E. canis and A. phagocytophilum was registered in 2 dogs (0.2%). The geographical distribution of the seropositive cases suggests clustered foci in southern regions and in the western part of the country for D. immitis, and in the southeastern region (Constan?a County) for E. canis. A. phagocytophilum and B. burgdorferi showed a homogenous distribution, with a tendency for Lyme-positive samples to concentrate in central Romania. For D. immitis, A. phagocytophilum, and E. canis, administering prophylactic treatments was a risk factor associated with infection. Another associated risk factor was the type of dog (stray dogs were at risk being positive for D. immitis, shelter dogs for E. canis, and hunting dogs for B. burgdorferi). The prevalence of D. immitis was significantly higher in males and in dogs older than 2 years. This survey represents the first data detailing A. phagocytophilum and E. canis seroprevalence in Romanian dogs, and the most comprehensive epidemiological study on vector-borne infections in dogs from this country.  相似文献   
87.
88.
Catalytic methane steam reforming was conducted at low temperature using a Pd catalyst supported on Ce1−xMxO2 (x = 0 or 0.1, M = Ca, Ba, La, Y or Al) oxides with or without an electric field (EF). The effects of the catalyst support on catalytic activity and surface proton hopping were investigated. Results show that Pd/Al-CeO2 (Pd/Ce0.9Al0.1O2) showed higher activity than Pd/CeO2 with EF, although their activity was identical without EF. Thermogravimetry revealed a larger amount of H2O adsorbed onto Pd/Al-CeO2 than onto Pd/CeO2, so Al doping to CeO2 contributes to greater H2O adsorption. Furthermore, electrochemical conduction measurements of Pd/Al-CeO2 revealed a larger contribution of surface proton hopping than that for Pd/CeO2. This promotes the surface proton conductivity and catalytic activity during EF application.

Temperature dependence of electron/ion conductivity of Pd/CeO2 and Pd/Al-CeO2 under wet conditions with application of an electric field.  相似文献   
89.
Cerebral venous sinus thrombosis (CVST) is rare but displays various and often dramatic clinical symptoms. Few cases of CVST have been reported in the field of anesthesiology. We encountered an unexpected case of CVST that presented with delayed emergence from anesthesia after resection of a brain tumor. A 55-year-old man was scheduled for resection of an oligoastrocytoma in his right frontal lobe. After smooth induction of general anesthesia, anesthesia was maintained uneventfully for about 7 h with target-controlled infusion (TCI) of propofol and remifentanil, except for a seizure generated when the right anterior central gyrus was stimulated to allow motor evoked potential monitoring. Immediately after the cessation of TCI, spontaneous respiration was restored. However, the patient was unexpectedly comatose, and no response to painful stimuli or coughing during tracheal suctioning was observed. A computed tomogram taken 2 h after surgery showed diffuse brain edema, even though the neurosurgeons did not notice any cerebral swelling during closing of the dura mater. A magnetic resonance venogram revealed thromboses in the superior sagittal and straight sinuses. On the 9th postoperative day, the patient died without recovering consciousness or his brainstem reflexes. Anesthesiologists should be aware of CVST as a cause of delayed emergence from anesthesia after craniotomy.  相似文献   
90.

Background

This study was designed to determine the surgical outcomes of gastric cancer in elderly patients. This information can help establish appropriate treatment for these patients.

Methods

A total of 1,193 patients with gastric cancer who underwent gastrectomy between 1995 and 2010 were enrolled in this retrospective study. The clinicopathologic features of 104 elderly patients (aged ≥80 years) were compared with those of 1,089 nonelderly patients.

Results

(1) Tumors located in the lower-third of the stomach, differentiated cancer, and surgery with limited lymph node dissection were more common in elderly patients. However, there was no difference in the proportion of laparoscopic gastrectomy between elderly and nonelderly patients. (2) Although surgical complication rates were similar in the two groups, the operative mortality rate was higher in elderly patients (1.9 %) than in nonelderly patients (0.7 %). (3) Elderly patients had a significantly poorer overall survival rate, whereas the disease-specific survival rates of the two groups were similar. Limited lymph node dissection did not influence the disease-specific survival rate of elderly patients. (4) The median life expectancy of elderly gastric cancer survivors was 9.8 years in patients aged 80–84 years and 6.0 years in those ≥85 years. The patients with limited lymph node dissection had slightly better prognosis.

Conclusions

The treatment results in elderly patients were comparable to those in nonelderly patients. These findings suggest that R0 resection with at least limited lymph node dissection according to Japanese guidelines should be considered, even for elderly patients.  相似文献   
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