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991.
992.
Covariance of personality, neurocognition, and schizophrenia spectrum traits in the community. 总被引:1,自引:0,他引:1
Clinical researchers have observed in relatives of schizophrenic individuals abnormal personality traits resembling the psychopathology of schizophrenia. Further similarities have been observed in correlations between measures of brain function, including attention and executive abilities, and these personality psychopathologies. However, two methodologic factors might account for the covariation of these 'schizophrenia spectrum' personality traits and measures of brain function. Clinical selection bias (Berkson's bias) might result in subjects with overlapping conditions being more likely to be studied, and normal personality attributes could affect performance on neurobehavioral tasks. This study investigated relationships between neurobehavioral correlates of schizophrenia, clinical schizophrenia spectrum personality traits, and normal personality dimensions in the five-factor model of personality. To avoid Berkson's bias, subjects expected to have a high probability of spectrum traits were recruited from the Baltimore Epidemiologic Catchment Area Survey community sample. About 40% of the sample were found to have DSM-IIIR Schizotypal, Schizoid, or Paranoid Personality Traits or Disorders. Schizophrenia Spectrum traits showed significant associations with personality dimensions of the five factor model, particularly Openness to Experience and Neuroticism. In ordinary linear regression models, after adjustment for a number of normal personality characteristics, Schizotypal Personality Traits were still strongly associated with perseverative responses on the Wisconsin Card Sorting Test (WCST). In logistic regression models, subjects with Schizotypal, Schizoid, or Paranoid Traits differed in terms of normal personality profiles and WCST performance. 相似文献
993.
The Diagnostic Interview Schedule was used to identify 89 incident social phobia cases in wave 2 household subjects from 9437 at risk persons age 18 or older as part of the Epidemiologic Catchment Area study. Crude annual incidence of Diagnostic Interview Schedule/DSM-III social phobia was estimated at 9 per 1000 population per year. Onset of social phobia was associated with low education, never having been married and female gender. First onsets occurred throughout the life course of this adult sample. Nervousness, headache, panic spells, palpitations, other phobias, binge pattern of alcohol consumption, dysthymia and schizophrenic symptoms were also predictive of social phobia onset. There was no difference in predictive factors when “primary” social phobia (without premorbid panic) was analyzed separately. 相似文献
994.
MR fat suppression combined with Gd-DTPA enhancement in optic neuritis and perineuritis 总被引:1,自引:0,他引:1
A fat suppression MR technique used in combination with Gd-DTPA enhancement was investigated to determine its value in cases of inflammatory optic nerve lesions. This technique, the so-called hybrid method, is a derivative of the chopper fat suppression technique and provides water-only images without increasing the imaging or postprocessing time. The study group consisted of four patients with acute visual loss, all of whom received Gd-DTPA. Conventional T2-weighted and fat suppression post-Gd-DTPA T1-weighted images were obtained in all patients; in addition, in one patient a post-Gd-DTPA T1-weighted image without fat suppression was obtained. In three patients, the conventional T2-weighted images failed to reveal any abnormality. In contrast, the enhanced optic nerve and enhanced perineural inflammatory infiltrate were easily identified on T1-weighted images after administration of Gd-DTPA and application of fat suppression technique. The lesions in inflammatory optic neuritis or perineuritis were easily distinguished from the surrounding fat, which had been suppressed. This combined technique resulted in significantly improved definition of normal anatomic structures and made the enhancing lesions more conspicuous, especially in areas with large amounts of fat such as the retrobulbar orbit. 相似文献
995.
996.
R D Tien B C Ashdown D V Lewis M R Atkins P C Burger 《AJR. American journal of roentgenology》1992,158(6):1329-1332
Rasmussen's encephalitis is a devastating disease of childhood causing progressive neurologic deficits and intractable seizure activity. Patients frequently have episodes of epilepsia partialis continua and, much less frequently, generalized status epilepticus. The seizures are intractable despite aggressive medical management. In advanced cases, hemispherectomy appears to be the only option to control the seizures. Permanent physical and mental impairments are inevitable. The cause of this disease is unknown, although pathologic specimens demonstrate nonspecific changes that are compatible with viral encephalitis. The progressive brain damage is typically so insidious in onset and gradual in course that it is difficult to make an accurate diagnosis on the basis of clinical evidence. We retrospectively evaluated the CT, xenon CT, positron emission tomographic, and MR neuroimaging findings in four young patients with pathologically suspected Rasmussen's encephalitis (three patients had CT scans, two had xenon CT scans, two had MR scans, and one had a positron emission tomogram). All studies showed abnormalities of the involved cerebral hemisphere: CT and MR revealed nonspecific atrophy, xenon CT showed decreased cerebral blood flow, and positron emission tomography revealed a hypometabolic state. Rasmussen's encephalitis is a diagnosis of exclusion; however, the information obtained from neuroimaging studies in combination with the clinical course should suggest this disorder. 相似文献
997.
The magnetic resonance imaging (MRI) in 4 cases of subchondral cyst at the knee joint region, were acquired from a 1.5 Tesla imager. We found a high incidence of concomitant occurrence of subchondral cysts with a ruptured anterior cruciate ligament (ACL) in all of these cases. The 2 men and 2 women, had an average age of 35. Clinically, they complained of dull knee pain and mild instability. Conventional radiography detected subchondral cysts in 3 of them, while MRI disclosed that all of the subchondral cysts were at the tibial plateau, close to the intercondyloid eminence. To date, MRI is the only imaging modality which can depict the concomitant occurrence of a subchondral cyst and a ruptured anterior cruciate ligament at the knee joint. Whether these subchondral cysts were the consequences of the ruptured anterior cruciate ligaments as one of the causes in addition to synovial fluid intrusion and bony contusion, need further clinical observation and investigation. 相似文献
998.
MR imaging of pineal tumors 总被引:6,自引:0,他引:6
MR images of pineal region tumors were analyzed in 26 patients with histologically proved tumors: seven germ-cell tumors, six astrocytomas, five teratomas, three pineoblastomas, two meningiomas, one dermoid, one epidermoid, and one metastasis. In an attempt to identify specific MR characteristics of these lesions, Gd-DTPA was administered to six patients. CSF and blood serum were assayed for alpha-fetoprotein (AFP) and human chorionic gonadotropin-beta subunit (HCG-beta) in 18 patients. MR findings were correlated with age, sex, the presence of biochemical tumor markers, and surgical outcome. We found that the most important factors in the determination of tumor type were the patient's age and the tumor markers. Increased levels of both HCG-beta and AFP were specific for patients with malignant teratomas and undifferentiated germ-cell tumors. HCG-beta alone was elevated in the patient with choriocarcinoma; only AFP was elevated in the patient with an endodermal sinus tumor. Tumor markers were not present in other patients in this series. The tumor size and the presence of fat were also helpful in determining tumor type. Hemorrhage was rare, seen only in the patient with a choriocarcinoma. Gd-DTPA did not enhance diagnostic specificity but aided in the detection of tumor seeding through CSF. We conclude that, although MR is sensitive in the detection of pineal region tumors and provides superb anatomic detail, MR signal characteristics are usually nonspecific. Correlation with the patient's age and the tumor markers significantly improves diagnostic accuracy. 相似文献
999.
Abstract Single dose of 0.6 or 1.2 mg/kg of rubratoxin B was administered intraperitoneally into the pregnant S1c: ICR mice on one day between day 6 and day 9 of gestation, and the fetuses were examined on day 18 of gestation. Gross malformations produced were neural tube defects, omphalocele, cleft palate, short or kinky tail, clubfoot and micromelia. Razor blade sections revealed dysgenetic hydrocephaly, microphthalmia, anophthalmia, renal hypoplasia, unilateral absence of kidney and uterine horn hypoplasia, ventricular septal defect (VSD) and apex bifida of the heart. Skeletal specimens showed dislocation, deformity, fusion, splitting or absence of vertebral bodies, fusion of vertebral arches, fused ribs, and scoliosis. Delayed ossification of axial and appendicular skeleton was also noted.
The sensitive periods for the above rubratoxin B-induced malformations were restricted in the beginning of organogenetic period. No rubratoxin B-specific type of malformations was found. 相似文献
The sensitive periods for the above rubratoxin B-induced malformations were restricted in the beginning of organogenetic period. No rubratoxin B-specific type of malformations was found. 相似文献
1000.