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71.
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The value of CT scanning in radiation therapy treatment planning: a prospective study 总被引:1,自引:0,他引:1
M Goitein J Wittenberg M Mendiondo J Doucette C Friedberg J Ferrucci L Gunderson R Linggood W U Shipley H V Fineberg 《International journal of radiation oncology, biology, physics》1979,5(10):1787-1798
We report the results of a prospective study in which we assessed the value of computed tomography (CT) scanning in planning radiation therapy for 77 patients. First, conventional studies were performed, treatment fields were designed and simulated and, where appropriate, computer generated treatment plans drawn up. Then a CT scan was performed to delineate the location of the tumor and adjacent uninvolved tissues. The treatment goals and plans were reevaluated and changed when necessary.Forty of the 77 patients (52 %) had their treatment changed as a result of the CT scan. Of these, four (5 % ) had a change of treatment modality. Thirty-two patients (42%) had changes in the radiotherapy technique because of inadequate tumor coverage (in 24 patients (31 %) part of the tumor was outside one or more of the fields and in the other 8 patients (10 %) the tumor coverage was marginal). Field changes resulting only from considerations of normal tissue coverage were made for 4 of these patients (5%). In total, normal tissue coverage was affected in 36 patients (47%).When the significance of these changes was evaluated, CT scanning was judged to be of major value for 28 of the 77 patients (36%) and of minor value in a further 12 patients (16%). 相似文献
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The results of surgical treatment alone for 142 cases of carcinoma of the rectum and rectosigmoid from the Massachusetts General Hospital were reviewed. The incidence of local failure as any component of failure was found to be strongly dependent on the pathologic stage, and for Dukes' A was 8.0% (3/39); Dukes' B, 31% (18/59), and Dukes' C, 50% (22/44). The incidence of local failure for tumors without lymph node metastasis was 17% with only microscopic extension through the wall (modified Astler-Coller Stage MAC-B2m), but increased to 54% in tumors that were adherent to or invading adjacent organs and structures (MAC-B3). Similarly, in tumors with positive lymph nodes, there was a 36% incidence of local failure for tumors confined to the wall or with only microscopic extension through the wall (MAC-C1/C2m), compared to a 67% incidence for tumors with adherence or involvement of adjacent organs (MAC-C3). Other predictors of local recurrence were the tumor location, grade, number of lymph nodes, and blood vessel invasion. The pathologic factors predicting distant metastasis are also presented. Five-year survival for Dukes' A was 77% (30/39); Dukes' B, 44% (26/59); and Dukes' C, 23% (10/44). The implications for future adjuvant therapy based on the identification of patients with the highest risk for local and distant failure are discussed. 相似文献
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The cost of schizophrenia. 总被引:3,自引:0,他引:3
The cost of schizophrenia has been estimated at $11.6 to $19.5 billion annually. About two-thirds of this cost is due to lack of productivity by schizophrenic patients and about one-fifth to treatment costs. The estimate might be considerably higher if better figures were available on the cost of maintaining patients in the community. In the absence of more effective treatment, the savings from the current trend toward shorter hospitalization cannot be expected to decrease-and may actually increase-the overall costs of schizophrenia to society. The authors make recommendations aimed at reducing the cost by helping schizophrenic patients to be more productive through a system of community alternative-care facilities, increased rehabilitation services, aftercare, and research. 相似文献
76.
Acquired pendular nystagmus: its characteristics, localising value and pathophysiology 总被引:5,自引:4,他引:1 下载免费PDF全文
Investigations were made of 16 patients with acquired pendular nystagmus and a further 32 cases reported in the literature were reviewed. Amongst our own patients two thirds had multiple sclerosis, almost one third a cerebrovascular accident or angioma and two had optic atrophy with squint. The nystagmus took forms which could be monocular or binocular, conjugate or disconjugate and could involve movements about single or multiple axes. Spectral analysis was used to characterise the amplitude and frequency of the movements and to estimate the degree of relationship (coherence) between movements of the two eyes or between movements of one eye about several axes. The oscillations ranged in frequency from 2·5 Hz to 6 Hz, with typical amplitudes between 3° and 5°. In a given patient all oscillations, regardless of plane, were highly synchronised. Somatic tremors of the upper limb, face and palate associated with the nystagmus were often at similar frequencies to the eye movement. The other ocular signs common to all our patients were the presence of squint with failure of convergence. Most patients also had skew deviation or internuclear ophthalmoplegia or both. The major oculomotor systems, that is, saccades, pursuit, optokinetic and vestibulo-ocular reflexes could be intact. It is inferred that the mechanism responsible for the pendular nystagmus lies at a level which is close to the oculomotor nuclei so that it can have monocular effects but is not part of the primary motor pathways. It is possible that this mechanism normally subserves maintenance of conjugate movement and posture of the eyes. The periodicity of the nystagmus is likely to arise from instability in a certain type(s) of neurone, for the associated somatic tremors have similar characteristics and yet involve very different neuronal muscular circuitry. Prognosis for cessation of the nystagmus is poor. In five patients with multiple sclerosis it was suppressed by intravenous hyoscine with, however, unacceptable subsequent side effects. 相似文献
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OBJECTIVE: The aim of the present study is to investigate the effects of psychological factors on plasma lipid levels among rural women of central Wisconsin and to compare the effects of these variables among normal-weight and overweight women. METHODS: Stratified sampling was used to select a random sample (n=1500) of farm and non-farm women aged 25 to 71 years from the Central Marshfield Epidemiologic Study Area. The baseline examination included measurements of blood pressure, skin folds, height, weight, and fasting blood lipids, glucose, and insulin. Framingham study questionnaires were employed to measure anger, anxiety, tension, and marital disagreement. The Spielberger Trait anger-reaction subscale was employed to assess proneness to anger. RESULTS: Among normal-weight women, a positive association was found between anger-reaction scores and cholesterol (b=0.008), ratio (b=0.014), triglycerides (b=0.02), and LDL (b=0.07). The odds of elevated cholesterol were highest among women with high scores on the Speilberger anger-reaction scale (OR=2.0) and anger discussion scale (OR=2.0), while the odds were less among women with high scores on the anger-out scale (OR=0.59). However, among overweight women, we found only scores on the Framingham anger-discussion scale as an important factor to determine the plasma lipid levels. CONCLUSION: Anger management may help to sever the link between psychological factors and CHD risk factors. Intervention intended to prevent cardiac events through the reduction of stress and modification of related psychological risk factors have successfully improved the CHD risk factors profile. Similar studies are needed to determine the efficacy of intervention for the primary prevention of CHD risk factors. 相似文献
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