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71.
To test the hypothesis that the frequency of biotinidase deficiency is greater in children with unexplained developmental delay or neurologic abnormalities than in the general population, we studied children seen at a large outpatient clinic over a four-year period who had one or more of these neurologic abnormalities and for whom no specific cause for their abnormalities could be found. The group totaled 274 children (163 boys; 111 girls) whose ages ranged from 2 weeks to 17 years. Characteristics were IQ/DQ, 30 to 70 in the 115 for whom scores were available; 41% had seizures; 15% had sensorineural hearing loss; 54% showed gross motor delay or ataxia; and 27% had decreased muscle tone. One patient with a classical clinical picture of biotinidase deficiency was diagnosed during the study period and was not included in the study. None of the patients with nonclassic findings had a deficiency of biotinidase activity. Our results suggest that biotinidase deficiency does not account for a large proportion of children with unexplained neurologic abnormalities or developmental delay. This does not negate the importance of biotinidase testing in children with clinical patterns specifically suggestive of the deficiency.  相似文献   
72.
In women with normal pregnancy and with pathological pregnancy (pregnancy-induced hypertension, fetal growth retardation, hepatosis) trace elements concentrations (Fe++, Cu++, Zn++, Mg++) were determined in serum and erythrocytes. The concentrations were partly decreased or increased in both serum and erythrocytes, but these changes were not significant. Thus, the analyses of trace element concentrations can not be used as a marker of the investigated pathological events of pregnancy.  相似文献   
73.
The degree of fetal respiratory and body movements as well as of fetal heart rate reactivity was checked by synchronous ultrasonic and cardiographic monitoring of 18 normotrophic fetuses in the early and late dilation period. Apart from the fetal respiratory movements, which could no longer be observed in the late dilatation period, the degree of fetal body movements remained unaffected during the birth process. In the late dilatation period, the mean amplitude of heart rate accelerations occurring in association with fetal body movements was significantly lower than in the early dilatation period. In the unimpaired normotrophic fetus, however, the reactivity of the fetal cardiovascular system increased during the birth process in relation to the ratio of the amplitude of heart rate accelerations and the duration of associated fetal body movements. Hence, a decrease in fetal heart rate reactivity signals intranatal disturbance of the materno-utero-placento-fetal entity.  相似文献   
74.
BACKGROUND: Photodynamic therapy is a new option for treatment of choroidal neovascularisation in patients with age-related macular degeneration. But choroidal changes and associated angiographic characteristics have not been further evaluated. PATIENTS: Indocyanine green angiography was used to follow 38 patients with subfoveal choroidal neovascularisation in age-related macular degeneration over up to two years. All patients were treated with the photosensitizer Benzoporphyrin Derivative-MA receiving either a single or triple treatment. RESULTS: Indocyanine green angiography shows two effects of photodynamic therapy. On the one hand a selective and lasting closure of choroidal neovascularisation was documented. Choroidal neovascularisation-size and leakage was significantly reduced in the entire treatment group to 20.7% and 28.3% one week after treatment, followed by a slow increase to 33.3% and 41.2% at up to two years longterm follow up. On the other hand photodynamic therapy causes typically a peri-lesional hypofluorescence in Indocyanine green angiography. This hypofluorescence is most likely due to choroidal hypoperfusion and vascular endothelial changes. A continuous increase in fluorescence was shown, reaching again 90% of the pretreatment intensity at 3 months, documenting a good recovery of the choroidal network. CONCLUSION: The results show that photodynamic therapy is an alternative treatment in age-related macular degeneration with choroidal, subfoveal neovascularisation. Indocyaningreen angiography reflects well choroidal changes associated with this therapy and may be helpful to choose treatment intervals.  相似文献   
75.
The clinicopathologic and immunohistochemical features of 63 pleomorphic liposarcomas are presented. There were 35 men and 28 women (median age 63 years; range 18-93 years). Tumor size ranged from 2 to 23 cm (median 10 cm). Tumor locations included lower extremity (36.5%), especially the thigh (28.5%), limb girdles (17.5%), upper extremity (16%), thoracoabdominal wall (9.5%), and internal trunk (20.5%). A total of 75% were deep seated and/or extracompartmental. Histologically, lesions show a varying combination of lipogenic and nonlipogenic areas characterized by malignant fibrous histiocytoma-like, round cell liposarcoma-like, and/or epithelioid/carcinoma-like features. A pericytic pattern was focally present in 15 (24%) tumors. Eighteen (29%) lesions were grade 2, and 45 (71%) were grade 3 sarcomas. Tumor necrosis was observed in 51 (81%) cases, vascular invasion in three, and mitotic counts ranged from 3 to 124 per 10 high power fields (median 25). Lipogenic areas were S-100 protein immunoreactive, at least focally, in 20 of 42 (48%) cases. Nonlipogenic areas showed focal reactivity for smooth muscle actin (24 of 49; 49%), desmin (9 of 48; 19%), CD34 (18 of 45; 40%), S-100 protein (5 of 49, 10%), CD68 (6 of 46, 13%), and epithelial membrane antigen (13 of 49, 26.5%). Epithelioid areas showed epithelial membrane antigen (4 of 11; 36%) but not cytokeratin (0 of 11) reactivity. Treatment procedures in 51 patients consisted of simple tumorectomy (16) and wide excision (33). Five and 31 patients received neoadjuvant and adjuvant chemotherapy and/or radiation therapy, respectively. Follow-up (48 patients, range 7-276 months; median 38 months) showed a 45% local recurrence rate and a 42.5% metastasis rate, metastases occurring mostly in lungs and pleura. Seventeen patients (35%) died of disease, of whom none was metastatic at diagnosis. Five-year overall, metastasis-free, and local recurrence-free survivals were 57%, 50%, and 48%, respectively. Patient age > or =60 years, truncal tumor location, deep situation, tumor size >5 cm, vascular invasion, and incomplete tumor excision were significant adverse prognostic factors. Tumor grade and histology did not affect patient outcome. In conclusion, pleomorphic liposarcoma is a rare, often deep-seated and limb-based aggressive and metastasizing neoplasm of late adulthood. It shows a wide range of morphologic appearances, but tumor grade and histology have no effect on patient outcome.  相似文献   
76.
Photodynamic effects on choroidal neovascularization and physiological choroid   总被引:15,自引:0,他引:15  
PURPOSE: To evaluate the effect of photodynamic therapy (PDT) on perfusion and vascular integrity of choroidal neovascularization (CNV) and collateral physiological choroid. METHODS: In a prospective clinical trial, patients with subfoveal CNV were treated with PDT and verteporfin. Indocyanine green angiography (ICG-A), using a confocal laser scanning system with tomographic sections, was performed continuously 1 week before and 1, 4, and 12 weeks after and a mean long-term follow-up of 16.5 months after the final PDT. Vascular changes were localized tomographically and quantified on the level of the CNV and collateral choroid according to early lesion size, late hyperfluorescence, and persistence or recurrence. Data were analyzed separately from 38 eyes in a single- and 12 eyes in a multiple-treatment regimen. RESULTS: CNV lesions were significantly reduced in size and late hyperfluorescence. However, 54% of lesions primarily demonstrated persistence, typically of the choroidal feeding complex, which was only detectable by ICG-A. Regrowth from the feeding vessel occurred regularly, but did not reach baseline dimensions. Collateral choroid exposed to photoactivation exhibited choriocapillary occlusion. Progressive recanalization was documented within 4 to 12 weeks after both single and multiple PDT. Residual changes in the choroidal filling pattern often persisted during long-term follow-up. CONCLUSIONS: Tomographic ICG-A after PDT reveals persistence of CNV and/or the feeder vessel and a reduction in perfusion within the entire photosensitized area, including the surrounding choroid. Repair mechanisms occur slowly in neovascular and normal choroidal structures.  相似文献   
77.
PURPOSE: ICG angiography (ICGA) was used to document the effect of repeated PDT (verteporfin) on size and leakage of choroidal neovascularisation in age-related macular degeneration (AMD) and treatment-related side effects on the choroid. METHODS: Forty-two patients were followed over 24 months in a clinical trial for PDT in AMD. The ICGAs were performed every 3 months with a confocal laser scanning system. Patients received repeated verteporfin treatment. At each control visit, the patients were retreated if leakage was present in fluorescein angiography (FA). RESULTS: A continuous, highly significant reduction in CNV size and leakage area was found over 24 months. The initial CNV size dropped by 23% from 3.86 mm2 to 2.98 mm2. The leakage area in the late phase of the angiogram decreased by 30.3% from 5.0 mm2 to 3.5 mm2. A significant side effect of PDT on the choroid was documented by an increased hypofluorescent area in ICGA. The maximum size of the hypofluorescent area was reached after 12 months. At month 24, the choroidal fluorescence showed recovery in respect to area and intensity of fluorescence. But hypofluorescence surrounding the CNV lesion was already present in 40 out of 42 eyes before treatment. CONCLUSION: The ICGA confirms that repeated PDT treatments lead to a significant reduction in CNV size and leakage area over as long as 2 years. CNV lesions are surrounded by choriocapillary hypofluorescence in ICGA. PDT causes further hypoperfusion of the choroid but in the long-term significant recovery of choroidal perfusion was shown.  相似文献   
78.
79.
To study the molecular pharmacology of low-voltage-activated calcium channels in biophysical detail, human medullary thyroid carcinoma (hMTC) cells were investigated using the single-channel technique. These cells had been reported to express T-type whole-cell currents and a Ca(v)3.2 (or alpha 1H) channel subunit. We observed two types of single-channel activity that were easily distinguished based on single-channel conductance, voltage dependence of activation, time course of inactivation, rapid gating kinetics, and the response to the calcium agonist (S)-Bay K 8644. Type II channels had biophysical properties (activation, inactivation, conductance) typical for high-voltage-activated calcium channels. They were markedly stimulated by 1 microM (S)-Bay K 8644, allowing to identify them as L-type channels. The channel termed type I is a low-voltage-activated, small-conductance (7.2 pS) channel that inactivates rapidly and is not modulated by (S)-Bay K 8644. Type I channels are therefore classified as T-type channels. They were strongly inhibited by 10 microM mibefradil. Mibefradil block was caused by changes in two gating parameters: a pronounced reduction in fraction of active sweeps and a slight shortening of the open-state duration. Single recombinant low-voltage-activated T-type calcium channels were studied in comparison, using human embryonic kidney 293 cells overexpressing the pore-forming Ca(v)3.2 subunit. Along all criteria examined (mechanisms of block, extent of block), recombinant Ca(v)3.2 interact with mibefradil in the same way as their native counterparts expressed in hMTC cells. In conclusion, the pharmacologic phenotype of these native human T-type channels--as probed by mibefradil--is similar to recombinant human Ca(v)3.2.  相似文献   
80.
We report the case of a 30-year-old woman with a 7-year history of distal lower limbs weakness that evolved to upper limbs weakness. On neurological examination, she presented normal cranial nerves, bilateral quadriceps and feet interosseous atrophy, normal muscular tonus, muscular weakness more severe in dorsal feet interosseous and anterior tibial, and decreased deep tendon reflexes. Repetitive nerve stimulation of the ulnar and fibular nerves showed a decrement greater than 10% of the compound muscle action potential. Antibody against acetylcholine receptor titer was positive. Computed tomography scan of the thorax was normal. Thyroid function tests showed evidence of hyperthyroidism. Distal muscular weakness is a rare onset presentation of myasthenia gravis. However, myasthenia gravis must be considered in the differential diagnosis of distal limb weakness.  相似文献   
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