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141.
Summary In neurofibromas type I (plexiform) and type II (diffuse) the Schwann cell is the predominant cell in the neoplastic proliferation. Electron microscopic investigation of a neurofibroma with structures resembling tactile corpuscles (type III) revealed neoplastic proliferation of perineurial instead of Schwann cells. The tactile-like (pseudo-Meissnerian) corpuscles (corpuscules neurofibromateux) are formed by neoplastic perineurial cells. These cells have a tendency to wrap themselves around longitudinal structures, such as collagen fibres or axons, and to come into direct contact with the latter. This close relationship between the axon and the neoplastic perineurial cell, analogous to that between axon and Schwann cell, points to a neuroectodermal origin of the perineurial cell. The electron microscopic appearances suggest that either the Schwann cell or the perineurial cell is the essential neoplastic component of neurofibromas, the fibroblastic proliferation being a secondary phenomenon.
  相似文献   
142.
In a District General Hospital Diabetic Clinic 40.0% of a random sample of diabetics under the age of 65 years of age were hypertensive. Black patients (48.9%) had greater (p less than 0.05) prevalence of hypertension than Whites (37.5%) and Asians (35.4%). Hypertension was more prevalent in females (49.1%) than males (33.0%) (p less than 0.001) in each ethnic group except Asians, and patients not receiving insulin had greater prevalence (45.6%) than those on insulin (30.7%) (p less than 0.001), except black diabetics where the reverse was found. There was a positive relationship between age and systolic (p less than 0.00001) and diastolic blood pressure (p less than 0.00001) and a negative association between duration of diabetes and diastolic blood pressure (p less than 0.004) on multiple regression analysis but no relationship was noted between blood pressure and either weight or blood glucose. Forty-six percent of all hypertensives were receiving conventional anti-hypertensive drug therapy; 38.7% were normotensive with similar results in each ethnic group and between the sexes. Isolated systolic hypertension was the commonest form of hypertension (48.3%) with isolated diastolic hypertension (4.9%) the rarest. These findings were observed regardless of the ethnic group or gender. Although in the majority of cases hypertension was mild these data confirm the importance of routine blood pressure measurement in diabetic patients.  相似文献   
143.
A case of tetralogy of Fallot associated with anomalous origin of the right pulmonary artery from the ascending aorta and hypoplastic left pulmonary artery was successfully repaired. Following the simultaneous procedure with banding of the right pulmonary artery and replacement of modified Blalock-Taussig shunt to the left pulmonary artery at 34 days of age, the intracardiac repair was performed successfully at 1 year and 10 months of age. The patient was well 6 months postoperatively, without unilateral pulmonary hypertension.  相似文献   
144.
Correct diagnosis of intracanalicular neoplasms is important to avoid unnecessary operations or an unsuitable surgical approach. We investigated the capability of high-resolution three-dimensional MR imaging in predicting the origin of intracanalicular neoplasms. Twenty cases underwent three-dimensional Fourier-transformation (3DFT) constructive interference in steady state and contrast-enhanced 3DFT-fast low angled shot MR imaging and surgery. Seventeen cases underwent caloric test. MR diagnosis on the origin of intracanalicular neoplasms was compared with surgical results. For MR diagnosis, the origin of intracanalicular neoplasms was predicted according to the location of the tumor in the internal auditory canal (IAC) in two ways, i.e., determining (1) a single specific nerve of origin and (2) whether the tumor originated from the superior or inferior aspect of the IAC. Surgery could determine the nerve of origin in 16 cases (14 inferior and 2 superior vestibular schwannomas), but it was indeterminate in 4. Comparison between MR prediction and surgical results on a single nerve origin revealed exact agreement in five, but inconsistent in three. Regarding whether the tumor was derived from superior or inferior aspect of the IAC, agreement was found in 10 of the 16 cases (62.5%). Caloric test was abnormal in all patients examined but one with superior vestibular schwannoma. 3DFT-MR imaging was not particularly useful in predicting a precise nerve of origin of intracanalicular neoplasms. The prediction on whether the tumor originated in the superior or inferior aspect of the IAC was superior to caloric test, which might have clinical significance in treatment planning especially for hearing preservation surgery.  相似文献   
145.
Larsen PL  Tos M 《The Laryngoscope》2004,114(4):710-719
OBJECTIVES/HYPOTHESIS: To further elucidate the natural history, etiology, and pathogenesis of nasal polyps, the present study of their anatomical site of origin was undertaken. The possibility for preferred areas or certain patterns in the places of origin was also considered. STUDY DESIGN: Autopsies were examined consecutively. METHODS: Endoscopic examination of the nasal cavity and paranasal sinuses, including endoscopic sinus surgery, was performed in 69 autopsies. The place of origin and attachment of each polyp was meticulously described. Polyps were photographically documented in situ and removed, together with the corresponding mucosa, for later histological examination. The cause of death of the patients was either cardiopulmonary disease or malignant diseases. Median age was 73 years (age range, 47-94 y). RESULTS: Nasal polyps were found in 22 of the 69 autopsies, corresponding to a frequency of 32%. In all, 54 polyps were found. Thirty-nine polyps were small (length, 2-5 mm), 10 were medium-sized, and 5 were large. No complaints of symptoms from the nasal polyps were registered. Most of the polyps (40 of 54 [74%]) originated in relation to sinus outlets. Most of these (34 of 54 [63%]) were found in the middle or superior meatus (13 of 54 [24%]). CONCLUSION: The results seemed to indicate that the frequency of nasal polyps is high and that most of the polyps originate from the mucosa of the ostia, clefts, and recesses in the ostiomeatal complex where the initial stage of sinonasal polyposis seems to take place. Continuous postmortem studies in autopsy materials and systematic endoscopic examinations for "silent," asymptomatic nasal polyps in various groups of patients will lead to a better understanding of the natural history of nasal polyps.  相似文献   
146.

Background

Common origin of the carotid arteries (COCA) is a normal anatomic variant reported to occur in approximately 11% of the general population. The objective of this study was to determine whether this variant places venoarterial extracorporeal membrane oxygenation (ECMO) patients at a higher risk for adverse neurologic sequelae owing to potential occlusion of both carotid arteries by the arterial cannula.

Methods

The authors reviewed clinical records and echocardiograms of the initial 220 ECMO patients at their institution. Aortic arch morphology was determined by a pediatric cardiologist blinded to all other data. After exclusion of predetermined patients, 131 patients were divided into 2 groups: those with separate origin of the carotid arteries (n = 111) and those with COCA (n = 20). The neurologic outcome variables studied included the results of magnetic resonance imaging (MRI); computed tomography (CT); electroencephalogram (EEG); brainstem auditory-evoked response (BAER), head ultrasound scan, and Bayley Scales of Infant Development reported as Psychomotor Developmental Index (PDI) and Mental Developmental Index (MDI).

Results

COCA had no predictive value in determining PDI and MDI outcomes and no significance in predicting an increased risk of adverse neurologic sequelae based on MRI, CT, EEG, BAER, or head ultrasound scan.

Conclusions

This study confirms that COCA is a common aortic arch variant (15%, n = 20 of 131) and that this variant does not appear to increase the risk of neurologic injury in infants undergoing venoarterial ECMO.  相似文献   
147.
中医形神观源流与内涵   总被引:2,自引:0,他引:2  
生命观中的形神理论是重要的哲学命题,也是中医学独具特色的重要学术思想之一.它由来古代灵与肉、形与神分离的二元认识,并逐渐由形神分离向形神相即、形神合一的方向发展.其内涵:形即形体,泛指脏腑经络等组织器官,也包括精、气、血、津液;神指人体生命的一切外在表现,包括工作、摄食、代谢、生育等一系列生命活动以及精神意识的思维活动.作为中医理论重要学术思想,在<内经>中有着广泛体现.  相似文献   
148.
Abstract:   The case histories of two children with horizontally acquired HIV infection are described. These children were diagnosed at a paediatric hospital in sub-Saharan Africa. Although the source(s) of infection was not identified, both children had had several contacts with the health service, experienced invasive procedures and ingested expressed milk from their own mothers during hospital admission. Health-care institutions, particularly those located in high HIV prevalence areas, must implement effective infection control measures to ensure that the risk of horizontal infection is minimized. Attention should be given to practices that are unique to each clinical discipline.  相似文献   
149.
Mutations in the DYT1 gene cause idiopathic torsion dystonia (ITD) transmitted in families as an autosomal dominant trait with incomplete penetrance. The most common mutation, 946delGAG, has been observed in populations with different ethnic and geographic origins. We have investigated 40 individuals from 22 unrelated families with ITD originating from the Land of Valencia, Spain, for the presence of this mutation and we found 5 patients and 6 unaffected subjects from 4 families who were carriers of the mutation. This finding indicates that 18% of families may be diagnosed as DYT1 and that penetrance is reduced. We detected two different geographic and linguistic origins of the Valencian families. However, by haplotype analysis using D9S1260, D9S1261, D9S63 and D9S1262 as flanking markers, we demonstrated that all affected and unaffected carriers shared a common chromosome confirming identical origin of the mutation in the four families. We postulate a unique origin for the 946delGAG mutation in the Land of Valencia and, based on linguistic criterion, we propose that the mutation might have occurred at the beginning of the second millennium. Genetic analysis of another family from Castilla-La Mancha showed a different haplotype segregating with the disease, suggesting that at least two distinct mutational events for the 946delGAG mutation have occurred in Spain.  相似文献   
150.
Summary ¶Background. Non-traumatic acute subdural haematomas enable study of the morbidity and mortality due to the haematoma without the effect of trauma. Whereas it is known that coagulation disorders worsen the outcome of spontaneous intracerebral haematomas, this has not been studied in non-traumatic acute subdural haematomas. Methods. In a series of 13 non-traumatic acute subdural haematomas admitted to our department between January 1995 and March 2002, we had 9 coagulopathy associated haematomas and 3 haematomas corresponding to the syndrome of spontaneous acute subdural haematoma of arterial origin. Both groups were compared. Findings. Age and gender distribution were comparable. The bleeding source was a cortical artery in 2 of the 2 non-coagulopathy related haematomas operated on, but also in 2 of the 4 coagulopathy associated haematomas that underwent surgery. The average haematoma thickness was higher in the coagulopathy related haematomas. The mean Glasgow Coma Score on admission was 7,7 and the mortality rate was 55,6% in the coagulopathy related group. In the non-coagulopathy related haematomas the mean Glasgow Coma Score was 12,0 and the mortality rate 33,3%. The latter mortality rate corresponds well to that of a historical group of spontaneous acute subdural haematomas of arterial origin collected from the literature. Interpretation. The outcome was worse in the non-traumatic acute subdural haematomas that were associated with a coagulation deficiency. While in all non-traumatic acute subdural haematomas the interval to surgery should be minimized, early recognition and urgent correction of coagulation deficiencies is certainly indicated.Published online May 19, 2003  相似文献   
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