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991.
Little is known about the vasoactivity of cerebral arterioles in extremely premature infants. We have assessed the effects of a small rise in PaCO2 of 1 kPa (7.5 mm Hg) on cerebral blood flow velocity measured by duplex Doppler ultrasound. Nineteen mechanically ventilated infants of 33 wk gestational age or less in whom direct arterial blood pressure monitoring was available, were studied on 45 occasions. There was a close relationship between increasing PaCO2 and increasing cerebral blood flow velocity (p less than 0.005) but on seven of 45 occasions the cerebral blood flow velocity fell with rising PaCO2. There was a 44% (median value) rise in cerebral blood flow velocity per 1 kPa rise in PaCO2 (5.9%/1 mm Hg) in 21 infants tested within 24 h of birth and this increased to a 53% (median value) rise (7%/1 mm Hg) in 20 infants tested after 24 h (p less than 0.001). Eleven infants had paired studies, the first within 24 h and a second at a median age of 48 h. There was a statistically significant increase in percentage reactivity when the later group was compared to those tested within 24 h (p less than 0.001). Carbon dioxide reactivity was also assessed before and after indomethacin infusion (0.2 mg/kg) on four occasions and there was a reduction in reactivity from a median value of 144 to 49.5%, 10 min after indomethacin. The extremely immature, ill infant is less sensitive to a small change in PaCO2 within 24 h of birth and after indomethacin infusion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
Metaiodobenzylguanidine (MIBG) has been used for the detection and treatment of neuroectodermal tumors, including neuroblastoma. We report our experience with 131I-MIBG used diagnostically in neuroblastoma patients with relapse. Thirty-eight studies were performed in 26 patients. There were 24 children (range 3 months-14 years) and two adults. While the study was found to be both sensitive and specific for the presence of disease, there are instances of discordance. False-negative studies were found with a markedly anaplastic tumor and with two mature ganglioneuromas. A bone lesion was negative with 131I-MIBG, but positive on bone scan. A biopsy confirmed the presence of neuroblastoma. Caution should be exercised when scanning pretreated patients, and perhaps with newly diagnosed patients as well.  相似文献   
993.
The radial forearm flap in head and neck reconstruction   总被引:1,自引:0,他引:1  
The radial forearm flap has proven to be a very reliable and versatile technique for reconstructing head and neck defects. It is of particular value where segmental defects in the mandible and intraoral mucosa exist, and in reconstructing defects within radiated tissue. The skin of the flap drapes well over the radial bone to allow denture fitting. The radial bone provides an adequate bony strut to allow essentially normal mandibular function. In a previously radiated bed, the flap (from a non-irradiated area) has the virtue of being highly vascular, thus benefiting wound healing. The lack of bulk in the flap prevents separation at the site of inset as wound healing occurs. It is a one-stage reconstruction, and since the donor site is on the upper extremity, early patient mobilization is possible. The donor defect is cosmetically acceptable, and since it lies against the body in the position of rest, it is not frequently exposed. The osseous portion of the flap in a postmenopausal woman should be approached with caution and patients should be warned of the risk of radius fracture. This flap is capable of providing tissue for reconstruction of the head and neck and should be considered for closure of all major defects, particularly those with bone defects or in defects created postirradiation.  相似文献   
994.
Vulvar and groin skin from 21 women with clinical squamous cell carcinoma of the vulva was compared with that from nine patients with vulvar intraepithelial neoplasia. Feulgen-stained nuclear densitometry showed a constancy of Feulgen-deoxyribonucleic acid (DNA) density in normal epithelium and all subepithelial connective tissue nuclei. At three sites--tumor edge, opposite labia, and perineum--there were significant differences in nuclear chromatin content between the two groups and also as compared with normal epithelium.  相似文献   
995.
Infants weighing 1500 g at birth requiring either intermittent positive pressure ventilation or continuous positive airway pressure by 12 hours of age were entered in a randomized double blind controlled trial to test the efficacy of early intravenous indomethacin therapy in preventing chronic pulmonary disease of prematurity. Of the 30 newborns enrolled, 15 were treated with indomethacin and 15 were treated with placebo at 12, 24 and 36 hours of age. The groups were similar for birth weight, gestational age, sex, hyaline membrane disease and intracranial hemorrhage. Infants in the placebo group were successfully weaned from intermittent positive pressure ventilation at an earlier age than infants in the indomethacin group (p less than 0.05). Furthermore, chronic pulmonary disease of prematurity was similar in the two groups despite a reduction in the incidence of patent ductus arteriosus in the indomethacin group.  相似文献   
996.
Summary: Patients with moderate to severe hirsutism presenting over an 18-month period to an endocrine clinic were assessed by clinical evaluation and hormone measurements. Hair growth rate was estimated by a photographic technique and the severity of hirsutism graded using an objective scale. Of 43 patients, 9 had polycystic ovaries and the remainder were considered to have idiopathic hirsutism. The most severely affected group had significantly increased hair growth rates compared with less clinically affected subjects, and 47% of this group showed objective features of virilization. However, apart from a significantly higher 24-hr urine 17-ketosteroid excretion all other hormonal patterns were not significantly different between severely and mildly affected patients. Serum levels of testosterone (T), sex hormone-binding globulin (SHBG), free T (calculated from T and SHBG values), and androstenedione (A) were abnormal in 44%, 51%, 60% and 60% of patients respectively, whereas plasma levels of the specific adrenal androgen DHAS were increased in 40% of patients. There was an overlap between patients with elevated hormone levels, although isolated elevation of T, A or DHAS were seen in 9%, 19% and 3% of patients respectively. In 19% of patients all serum androgen measurements were normal. Gonadotrophin levels were significantly lower in the more severely affected group. Thus androgen levels in patients with idiopathic hirsutism or polycystic ovaries, show considerable overlap with measurements in normal subjects, and elevated plasma androgens may be of adrenal (DHAS) or combined adrenal/ovarian (T, A) origin.  相似文献   
997.
998.
Despite the now widespread experience with the administration of chemotherapeutic agents in oncology, extravasation injuries still occur. Furthermore, the most appropriate management of such injuries is not known. The authors examined the current treatment options for extravasation injury and the incidence of this problem. All cases of extravasation referred to the plastic surgery service at one institution from 1994 through 1996 were examined. During a 6-year period there were 44 cases of extravasation injury identified in 42 patients. Comparison with a previous study conducted 15 years before at the same institution revealed a significant reduction in the incidence of extravasation injuries during that time (0.01% vs. 0.1%; = 0.00). The site of extravasation was peripheral in 32 cases and central in 12. Paclitaxel and doxorubicin were the two most common drugs involved. The local infusion of antidotes was not performed routinely. Only 26 of the 42 patients were referred to the plastic surgery service for care. Only 10 of those 26 patients required local ulcer excision and closure to achieve a healed wound. The mean time between injury and referral was 40 days. This time did not predict the subsequent need for a surgical procedure. Most patients, including the remaining 16 referred to the plastic surgery service, did not require surgical intervention. All were watched expectantly, and their injuries healed spontaneously. In conclusion, the incidence of extravasation is decreasing, most likely as a result of the diligence in the administration and identification of extravasation injuries as well as the result of the use of more central infusion sites. Most cases can be managed conservatively, with directed surgical treatment of the ulceration when appropriate.  相似文献   
999.
This is a preliminary investigation to detect the body sway and postural changes of patients with AIS under different spatial images. Two pairs of low-power prismatic eye lenses (Fresnel prisms) with 5 dioptre and 10 dioptre were used. In the experiment, the apices of the prisms were orientated randomly at every 22.5 degrees from 0 degrees to 360 degrees to test changes. Four patients with mean age of 11 and Cobb's angle of 30 degrees were recruited and the results showed that the low-power prisms at specific orientations (157.5 degrees and 180 degrees) could cause positive postural changes (2.1 degrees-2.7 degrees reduction of angle of trunk mis-alignment) measured by 3-D motion analysis. This might be used for controlling their scoliotic curves by induced visual bio-feedback. Apart from this laboratory test, a longitudinal study is necessary to investigate the long-term effect of the prisms at different powers and orientations (under both static and dynamic situations) on the patient's posture, spinal muscular activities, vision, eye-hand coordination, psychological state and other daily activities before it becomes an alternative management of AIS.  相似文献   
1000.
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