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11.
Multicystic dysplastic kidney is a common renal anomaly in the newborn. Long-term problems, such as pain, infection, hypertension and neoplasm, although infrequent, have been reported. Acute, life-threatening complications resulting from the size of the affected kidney are rare and emergency nephrectomy has been the only reported effective therapy. We present a case of ultrasound-guided percutaneous cyst decompression used as definitive treatment of respiratory failure associated with multicystic dysplastic kidney. 相似文献
12.
Cerebrospinal fluid rhinorrhea in patients with untreated pituitary adenoma: report of two cases 总被引:3,自引:0,他引:3
We report the cases of two patients with untreated pituitary adenoma who presented with cerebrospinal fluid rhinorrhea. The surgical treatment and mechanisms involved in this rare condition are discussed. 相似文献
13.
M J Khoury W Stewart A Weinstein S Panny P Lindsay M Eisenberg 《Journal of clinical epidemiology》1988,41(1):15-20
Although most teratogens are suspected to act early in the first trimester of pregnancy, birth defects monitoring programs and etiologic studies usually use residence at birth as a proxy measure for residence in the first trimester in searching for environmental teratogens. Because of the high mobility of the U.S. population, residence misclassification can potentially alter inferences concerning environmental teratogens. To evaluate this potential bias, data from the population-based Maryland Birth Defects Reporting and Information System were analyzed. In 1984, the system ascertained 295 infants with one or more of 12 sentinel defects. Of these cases, 59 (20%) mothers reported they have changed address between the time of conception and the time of birth, and 22 have moved to a different county. The residential mobility rate varied by demographic variables and was highest among white women, in the age group 20-24 years. If residence at birth is used as a screening test for residence at conception, it can be shown that in the presence of an environmental teratogenic exposure, misclassification of exposure increases with increasing mobility rate, and population exposure frequency. Such misclassification tends to weaken associations between residence and birth defects and may lead to missing environmental teratogens. This analysis emphasizes the need to use residence information early in pregnancy rather than exclusively at birth. 相似文献
14.
Summary Neurofibromatosis is sometimes complicated by impaired renal tubular reabsorption of phosphate, hypophosphatemia, and osteomalacia.
Hyperparathyroidism has also been reported in patients with neurofibromatosis. When hypercalcemia and elevated levels of parathyroid
hormone are found in osteomalacia, however, it may be difficult to determine if the hyperparathyroidism was primary or tertiary.
We describe a patient with neurofibromatosis, hypercalcemic hyperparathyroidism, hypophosphatemic osteomalacia, vitamin D
deficiency, and clear-cell hyperplasia of all four parathyroid glands. Serial biomechanical, bone biopsy, and densitometric
studies confirmed that treatment with ergocalciferol, calcium, and phosphate supplements significantly improved the osteomalacia
but caused increased parathyroid overactivity. After subtotal parathyroidectomy, the parathyroid hormone concentration became
normal and the bone mineral content increased at the spine and hip, but inappropriate phosphaturia persisted. The findings
indicate that hyperparathyroidism, osteomalacia, and vitamin D deficiency adversely affect each other. 相似文献
15.
16.
Robert L Jilka Robert S Weinstein A Michael Parfitt Stavros C Manolagas 《Journal of bone and mineral research》2007,22(10):1492-1501
Since the initial demonstration of the phenomenon in murine and human bone sections approximately 10 yr ago, appreciation of the biologic significance of osteoblast apoptosis has contributed greatly not only to understanding the regulation of osteoblast number during physiologic bone remodeling, but also the pathogenesis of metabolic bone diseases and the pharmacology of some of the drugs used for their treatment. It is now appreciated that all major regulators of bone metabolism including bone morphogenetic proteins (BMPs), Wnts, other growth factors and cytokines, integrins, estrogens, androgens, glucocorticoids, PTH and PTH-related protein (PTHrP), immobilization, and the oxidative stress associated with aging contribute to the regulation of osteoblast and osteocyte life span by modulating apoptosis. Moreover, osteocyte apoptosis has emerged as an important regulator of remodeling on the bone surface and a critical determinant of bone strength, independently of bone mass. The detection of apoptotic osteoblasts in bone sections remains challenging because apoptosis represents only a tiny fraction of the life span of osteoblasts, not unlike a 6-mo-long terminal illness in the life of a 75-yr-old human. Importantly, the phenomenon is 50 times less common in human bone biopsies because human osteoblasts live longer and are fewer in number. Be that as it may, well-controlled assays of apoptosis can yield accurate and reproducible estimates of the prevalence of the event, particularly in rodents where there is an abundance of osteoblasts for inspection. In this perspective, we focus on the biological significance of the phenomenon for understanding basic bone biology and the pathogenesis and treatment of metabolic bone diseases and discuss limitations of existing techniques for quantifying osteoblast apoptosis in human biopsies and their methodologic pitfalls. 相似文献
17.
Richard O. Wein MD Gregory S. Weinstein MD 《Operative Techniques in Otolaryngology》2003,14(2):129-149
The elective surgical treatment of the neck for advanced T-stage laryngeal presentations of squamous cell carcinoma is typically the anterolateral neck dissection. Modifications of the anterior-based technique that include the use of digastric and hypoglossal tunnels to establish reliable landmarks result in a reproducible technique. The complex anatomic relationships of the anterior and superior part of the neck dissection are exposed and protected early in the technique, making this approach ideal for use in an academic setting. 相似文献
18.
Silvio Taschieri Massimo Del Fabbro Tiziano Testori Luca Francetti Roberto Weinstein 《Journal of oral and maxillofacial surgery》2006,64(2):235-242
PURPOSE: The introduction of microsurgical instruments and magnification devices has brought advantages in root-end management and the application of root-end filling materials. The main purpose of this prospective clinical study was to monitor the outcome of ultrasonic root-end preparation using magnification loupes or an endoscope. Tooth location and the presence of post restoration were also examined as potentially affecting the outcome. MATERIALS AND METHODS: Teeth treated surgically showed a periradicular lesion of strictly endodontic origin. A total of 59 patients were included in the study, according to specific selection criteria. Following the reflection of a full mucoperiosteal tissue flap, residual soft tissues were curetted, root ends were resected, and root-end cavities were prepared ultrasonically with a zirconium nitrate tip, and zinc oxide EBA-reinforced cement root-end fillings were placed. Thirty-two root-end management procedures were performed using magnification loupes and 39 using an endoscope. All cases followed for a period of 1 year were classified into 3 groups (success, uncertain healing, and failure) according to radiographic and clinical criteria. RESULTS: Of the 71 teeth evaluated at 1-year follow-up, 67 teeth (92.95%) successfully healed, 3 teeth had uncertain healing, and 2 failed. In the group using endoscopy, 94.9% of successful healing was achieved, while for the other group, 90.6% was recorded. We found no statistically significant differences in treatment results related to the arch (P = .20), post restoration (P = .21), or type of magnification device (P = .08). CONCLUSIONS: In the present study, adherence to a strict endodontic surgical protocol and the use of modern surgical endodontic procedures, together with visual magnifications, resulted in an overall high success rate. 相似文献
19.
B. Falk Y. Weinstein R. Dotan D. A. Abramson D. Mann-Segal J. R. Hoffman 《Scandinavian journal of medicine & science in sports》1996,6(5):259-264
Anaerobic power is characterized by a high degree of specificity regarding both the recruited muscles as well as the recruitment pattern. The popular Wingate Anaerobic Test (WAnT) is a cycling test that does not satisfy the need for a running-specific anaerobic test. We describe such a test, using a novel type of a commercially available treadmill (BRL 1800, Gymrol, France). The ergometer is equipped with a torque motor to neutralize the frictional resistance of the treadmill belt, and a hip-belt harness connected to a horizontal rod. Force applied to the harness is monitored by a strain gauge mounted on the rod, while vertical movement is monitored by a potentiometer at the posterior fixed end of the rod. These, in conjunction with the treadmill belt speed, enable the computation of horizontal and vertical power as well as the combined total output. Power is calculated both as 'peak' power (highest 2.5 s segment) and 'mean' power (20 s duration). Preliminary results of young athletes were generally consistent with the expected age-related changes in anaerobic power. Values obtained on the anaerobic treadmill were always higher than the corresponding WAnT values previously obtained in comparable age groups. The higher values were probably due to the larger muscle mass involved and the shorter peak and mean power durations (2.5 and 20 s versus 5 and 30 s in the WAnT, respectively). This test should enable not only running-specific anaerobic power monitoring but also the characterization of the relationship between the horizontal and vertical components of that power. 相似文献
20.