全文获取类型
收费全文 | 41055篇 |
免费 | 2382篇 |
国内免费 | 215篇 |
学科分类
医药卫生 | 43652篇 |
出版年
2024年 | 43篇 |
2023年 | 450篇 |
2022年 | 1151篇 |
2021年 | 1829篇 |
2020年 | 1062篇 |
2019年 | 1384篇 |
2018年 | 1715篇 |
2017年 | 1241篇 |
2016年 | 1330篇 |
2015年 | 1439篇 |
2014年 | 1846篇 |
2013年 | 2245篇 |
2012年 | 3398篇 |
2011年 | 3314篇 |
2010年 | 1901篇 |
2009年 | 1629篇 |
2008年 | 2427篇 |
2007年 | 2504篇 |
2006年 | 2222篇 |
2005年 | 1957篇 |
2004年 | 1798篇 |
2003年 | 1486篇 |
2002年 | 1298篇 |
2001年 | 429篇 |
2000年 | 378篇 |
1999年 | 332篇 |
1998年 | 213篇 |
1997年 | 149篇 |
1996年 | 163篇 |
1995年 | 118篇 |
1994年 | 104篇 |
1993年 | 92篇 |
1992年 | 176篇 |
1991年 | 183篇 |
1990年 | 157篇 |
1989年 | 152篇 |
1988年 | 124篇 |
1987年 | 121篇 |
1986年 | 113篇 |
1985年 | 133篇 |
1984年 | 100篇 |
1983年 | 70篇 |
1982年 | 70篇 |
1981年 | 68篇 |
1980年 | 45篇 |
1979年 | 64篇 |
1978年 | 58篇 |
1977年 | 43篇 |
1974年 | 40篇 |
1973年 | 44篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
Medium-Depth Chemical Peels in the Treatment of Acne Scars in Dark-Skinned Individuals 总被引:2,自引:0,他引:2
BACKGROUND: Multiple modalities are available for treating acne scars, one of which is chemical peeling. OBJECTIVE: To evaluate the efficacy of medium-depth peels in the treatment of acne scars. METHODS: A total of 15 patients (14 women and 1 man) were seen between November 1998 and March 2000. A medium-depth chemical peel was performed. The peel was performed using a combination of Jessner's solution followed by the application of 35% trichloroacetic acid (TCA). The mean age of patients who entered the study was 28 years. A total of 42 peeling sessions were performed: 13 patients had the full three-session regiment, 1 patient had two sessions, and 1 had only one session. RESULTS: Patients in our study had two forms of acne scars, the atrophic saucer or crater-like form and the pitted (ice-pick) form. Improvement occurred in all except one of our patients. Significant improvement (greater than 75% clearance of lesions) occurred in 1 patient (6.6%), moderate improvement (51-75% clearance) in 8 patients (53.3%), mild improvement (26-50% clearance) in 4 patients (26.6%), minimal improvement (1-25% clearance) in 1 patient (6.6%), and no response in 1 patient (6.6%). All patients had different combinations of the above two forms. Four patients (26.6%) had mainly pitted scars and deep atrophic scars. The clinical response in those patients was moderate, mild, minimal, and no response, respectively. The remainder of our patients had mainly atrophic scars of moderate depth. Nine patients (73.4%) suffered from transient postinflammatory hyperpigmentation. In two of them it was preceded by erythema that lasted for more than 1 month. All patients were free of noticeable pigmentation 3 months after the final peel. Patients in whom hyperpigmentation did not develop were of light brown complexion. CONCLUSION: We conclude that medium-depth chemical peel is a safe and effective method of treating acne scars even in patients with dark complexion. 相似文献
42.
Background
Given the proliferation and the growing complexity of performance measurement initiatives in many health systems, the Netherlands and Ontario, Canada expressed interests in cross-national comparisons in an effort to promote knowledge transfer and best practise. To support this cross-national learning, a study was undertaken to compare health system performance approaches in The Netherlands with Ontario, Canada. 相似文献43.
44.
45.
Ali Samii Debra D Dahlen Alexander M Spence Nicole C Maronian Eric E Kraus Vanda A Lennon 《Movement disorders》2003,18(12):1556-1558
The paraneoplastic autoantibody, collapsin response-mediator protein (CRMP)-5 immunoglobulin G (IgG), is specific for neuronal cytoplasmic CRMP-5, and is usually associated with small-cell lung carcinoma or thymoma. We report on details of a movement disorder that followed anti-B-cell therapy in a patient with lymphoma, and was accompanied by CRMP-5 IgG. 相似文献
46.
Bülent Gül Sezer Kulaçoglnu Dr. Muammer Yükse Handan Dogan Ali Ihsan Ökten 《Neurosurgical review》1997,20(1):59-61
Esthesioneuroblastoma is an uncommon malignant neoplasm that arises from olfactory mucosa, often with intracranial extension.A case report of the youngest victim in the literature (2-year-old boy) is presented. 相似文献
47.
Pathological changes in testes and liver of male albino rats after dermal exposure to DDVP insecticide. 总被引:1,自引:0,他引:1
Exposure of male albino rats to DDVP insecticide at sublethal dose of 30 mg/kg/day through dermal painting for a period of 90 days didn't show any intoxication symptoms or mortality. However, cytopathological changes in testicular and liver tissues were evident. There was a positive correlation between the degree of cellular damage and the period of insecticide administration. In general, damages were prominent in rats treated for 30 days or more. Histological examination of testes showed degenerative seminiferous tubules and fewer leydig cells. Hepatic cells were congested, atrophied and showed different stages of necrobiotic changes. This suggests a great care and caution for workers during different phases of DDVP insecticide handling. 相似文献
48.
Bone scintigraphy in tuberculous sacroiliitis 总被引:1,自引:0,他引:1
Radionuclide bone imaging is becoming increasingly important in the evaluation of musculoskeletal pain of uncertain cause. A case in which Tc-99m MDP bone imaging was employed to investigate complaints of low back pain is presented. Scan abnormalities directed clinicians towards appropriate further workup and diagnosis of unilateral tuberculous sacroiliitis. 相似文献
49.
Jerrold S. Meyer Mark Grande Kenneth Johnson Syed F. Ali 《International journal of developmental neuroscience》2004,22(5-6):261
3,4-Methylenedioxymethamphetamine damages fine serotonergic fibers and nerve terminals in adult organisms. Developing animals seem to be less susceptible to this effect, possibly due to a lack of drug-induced hyperthermia. We tested this hypothesis by producing hyperthermia in neonatal rats for 2 h after each of twice-daily MDMA (10 mg/kg s.c.) or saline injections administered from postnatal days 1–4. Other drug-treated and control litters were maintained at normothermic temperatures following injection. Changes in forebrain serotonergic innervation were assessed at postnatal day 25 (serotonin transporter binding and serotonin levels), postnatal day 60 (serotonin transporter binding), and 9 months of age (serotonin transporter immunohistochemistry). We also determined the influence of MDMA treatment on apoptotic activity by means of immunohistochemistry for cleaved caspase-3 at postnatal day 5. The hippocampus showed significant MDMA-related reductions in serotonergic markers at postnatal day 25 and postnatal day 60. At 9 months, there was no effect of prior MDMA exposure on serotonin transporter-immunoreactive fiber density in the hippocampus; however, significant reductions in fiber density were observed in two neocortical areas and a hyperinnervation was found in the caudate-putamen and nucleus accumbens shell. MDMA treatment also produced a two-fold increase in the number of cleaved caspase-3-immunoreactive cells in the rostral forebrain and hippocampus. All of these effects were completely independent of pup body temperature. These findings demonstrate that neonatal MDMA administration exposure stimulates apoptotic cell death in various forebrain areas and also leads to a long-term reorganization of the forebrain serotonergic innervation. Consequently, offspring of MDMA-using women may be at heightened risk for abnormal neural and behavioral development. 相似文献
50.
Ali Ghoz Ehab Kheir Anil Kotru Karim Halazun David Kessel Jai Patel J J Peter A Lodge 《Hepatobiliary & Pancreatic Diseases International》2007,(3)
BACKGROUND:Spontaneous hemoperitoneum of hepato- biliary origin is commonly due to hemorrhage from a liver tumor.It is rarely caused by spontaneous rupture of aneurysm in visceral arteries. METHODS:We report an unusual case of hemoperitoneum caused by rupture of cystic artery pseudoaneurysm,and also outline the approach to its management through surgical and radiological methods. RESULTS:In our patient,the pseudoanurysm was initially treated with percutaneous thrombin injection.However this method of treatment failed after initial success.The pseudoanurysm was finally obliterated successfully using microcoil embolization. CONCLUSIONS:The mainstay of treatment of cystic artery pseudoaneurysm is cholecystectomy and ligation of the aneurysm.Recent publications showed success in using microcoil embolisation.In this case we also outline the use of percutaneous thrombin injection as a definitive treatment method and discuss its success or failure as a new method of treatment. 相似文献