全文获取类型
收费全文 | 36670篇 |
免费 | 3097篇 |
国内免费 | 362篇 |
专业分类
耳鼻咽喉 | 403篇 |
儿科学 | 992篇 |
妇产科学 | 975篇 |
基础医学 | 4577篇 |
口腔科学 | 589篇 |
临床医学 | 4118篇 |
内科学 | 7804篇 |
皮肤病学 | 837篇 |
神经病学 | 2700篇 |
特种医学 | 1225篇 |
外科学 | 5057篇 |
综合类 | 1177篇 |
一般理论 | 32篇 |
预防医学 | 2030篇 |
眼科学 | 1586篇 |
药学 | 2720篇 |
中国医学 | 307篇 |
肿瘤学 | 3000篇 |
出版年
2023年 | 315篇 |
2022年 | 526篇 |
2021年 | 989篇 |
2020年 | 666篇 |
2019年 | 817篇 |
2018年 | 1061篇 |
2017年 | 861篇 |
2016年 | 954篇 |
2015年 | 1144篇 |
2014年 | 1470篇 |
2013年 | 1763篇 |
2012年 | 2382篇 |
2011年 | 2486篇 |
2010年 | 1476篇 |
2009年 | 1345篇 |
2008年 | 1948篇 |
2007年 | 2016篇 |
2006年 | 2015篇 |
2005年 | 1945篇 |
2004年 | 1717篇 |
2003年 | 1599篇 |
2002年 | 1423篇 |
2001年 | 1136篇 |
2000年 | 1061篇 |
1999年 | 910篇 |
1998年 | 389篇 |
1997年 | 285篇 |
1996年 | 266篇 |
1995年 | 210篇 |
1994年 | 199篇 |
1993年 | 193篇 |
1992年 | 459篇 |
1991年 | 447篇 |
1990年 | 423篇 |
1989年 | 397篇 |
1988年 | 352篇 |
1987年 | 370篇 |
1986年 | 323篇 |
1985年 | 274篇 |
1984年 | 204篇 |
1983年 | 147篇 |
1982年 | 96篇 |
1981年 | 88篇 |
1980年 | 90篇 |
1979年 | 138篇 |
1978年 | 89篇 |
1977年 | 74篇 |
1976年 | 78篇 |
1975年 | 79篇 |
1972年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
J R Kosko B W Brandom K H Chan 《International journal of pediatric otorhinolaryngology》1992,23(1):45-50
It has been claimed that the combination of halothane and succinylcholine, commonly used for anesthetic induction during short pediatric otolaryngologic procedures, is associated with a 1% incidence of masseter spasm (MS) which may be an early sign of malignant hyperthermia (MH). An 18-month retrospective chart review of all patients undergoing general anesthesia at the Children's Hospital of Pittsburgh (n = 14, 112) was conducted to assess the incidence of MS and its management. In addition, a separate subgroup of patients identified as being at risk for MH was also evaluated. In the otolaryngology service, the incidence of developing MS was 2 of 206 (1%) in children who were anesthetized with halothane and received succinylcholine, patients were identified in the MH high-risk group, and none developed MH. The findings affirmed the risks of using this combination of anesthetic and neuromuscular blocking agents during induction and the need for establishing management guidelines. 相似文献
52.
An audit of the safety of an acute pain service 总被引:9,自引:0,他引:9
S. L. Tsui M. G. Irwin C. M. L. Wong S. K. Y. Fung T. W. C. Hui K. F. J. Ng W. S. Chan & A. M. O'Reagan 《Anaesthesia》1997,52(11):1042-1047
We audited and analysed the adverse effects and safety of postoperative pain management on 2509 consecutive patients under care of the Acute Pain Service at a tertiary referral teaching hospital over a 32-month period. Our standard respiratory monitoring consisted of continuous pulse oximetry, hourly respiratory rate counting, sedation scoring and intermittent arterial blood gas sampling. This protocol was reliable and detected six episodes of bradypnoea, 13 of hypercapnia and 23 of oxygen desaturation occurring in 39 patients (1.8% of all spontaneously breathing patients) . Two patients required naloxone injection and none had long-term sequelae. Hypotension due to epidural bupivacaine 0.0625% and fentanyl 3.3 μg.ml−1 infusion occurred in four patients (1.2%), all with a sensory block higher than T5 . They readily responded to fluid infusion and ephedrine (two patients). Postoperative nausea or vomiting occurred in 723 (28.8%) and 380 (15.1%) patients, respectively. Odds ratio analysis showed that the risk factors for postoperative nausea and vomiting were: female gender, gynaecological operations, nongeriatric patients and systemic analgesia. Postoperative nausea and vomiting decreased analgesic efficacy by discouraging the use of patient-controlled analgesia and was regarded as equally distressing as pain. Other side-effects included: pruritus in 182 patients; dizziness in 333 and lower limb weakness in 73 (21.2% of patients receiving epidural local anaesthetics). It is concluded that a standard monitoring and management protocol, an experienced nursing team and reliable Acute Pain Service coverage is mandatory for the safe use of modern analgesic techniques. 相似文献
53.
Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to
the lung, liver, and, less frequently, to the brain. Renal involvement is rare. Magnetic resonance imaging (MRI) is a useful
modality to image the affected tissues; it contributes to the evaluation and management of the disease. One case of renal
choriocarcinoma with MRI evaluation is reported.
Received: 24 February 1997/Accepted: 14 April 1997 相似文献
54.
OBJECTIVE: To assess changes in sociodemographic characteristics of mothers, their obstetric management and perinatal outcomes in the 1980s. DESIGN: A survey of data recorded in the South Australian perinatal data collection. For singleton births, we compared risks of stillbirth, neonatal death and perinatal death by year of birth, after adjusting for risk factors. SUBJECTS: There were 176,637 births of at least 400 g birthweight (or at least 20 weeks' gestation) notified to the perinatal data collection between 1981 and 1989. MAIN OUTCOME MEASURES: Frequency of risk factors and relative risks of stillbirth, neonatal death and perinatal death by year of birth. RESULTS: There have been changes in the sociodemographic characteristics of mothers, their obstetric management and perinatal outcomes during the 1980s. Crude perinatal mortality rates have not increased, despite increases in the frequency of low birthweight, preterm births, mothers aged 35 years and over, and some other risk factors. After adjusting for risk factors, the risks of stillbirth, neonatal death and perinatal death were lower among singletons in 1987-1989 than in the 1981-1982 reference period. CONCLUSION: Advances in clinical management may be preventing increases in stillbirths, neonatal deaths and perinatal deaths in response to increased numbers of births with low birthweight, preterm delivery and some other risk factors in South Australia. 相似文献
55.
In a group of patients with breast lumps, diagnosis made by pre-operative aspiration cytology was compared with that obtained by histological section of excised specimens. Results showed that aspiration cytology correctly diagnosed 89% of malignant lesions and 92.6% of benign lesions based upon histological diagnosis. Cytological diagnosis of benign disease had a false negative rate of 6% while cytological diagnosis of malignant disease had a 2.7% false positive rate. Only 3.5% of cytologies returned an inadequate diagnosis. This study shows that aspiration cytology should be useful in allowing a better psychological preparation of patients before surgery as well as better utilization of operation theatre facilities. 相似文献
56.
57.
Regional anaesthesia provides many advantages and can be practised safely in ambulatory surgery. It provides better postoperative pain control, avoids many complications associated with general anaesthesia and shortens recovery time. However, extra time required, associated complications and acceptance of patients are the factors of concern in practising regional anaesthesia in an ambulatory setting. This review will discuss various regional anaesthesia techniques suitable for outpatients. 相似文献
58.
One hundred eighty-two fine needle aspirations (FNAs) of head and neck masses performed between the years 1981 and 1987 were studied retrospectively. Seventeen FNAs were unsatisfactory. Of the remaining 165, 148 (90%) were followed up with either surgery or clinical follow-up of at least 12 months' duration. Seventy-one of these aspirates were malignant. Fifty-six cases of metastatic carcinoma and 13 cases of lymphoma were diagnosed. The positive predictive value for metastatic carcinoma and lymphoma was 100%, and the sensitivities were 92% and 100%, respectively. For benign salivary gland lesions, the positive predictive value was 94%, whereas for malignant lesions it was 100%. One case of carcinoma ex-pleomorphic adenoma was missed by FNA. No complications were associated with FNA. We conclude that FNA is a safe and accurate technique, well suited to the in-office evaluation of neck masses of differing causes. 相似文献
59.
Hidenori Endo Chikako Nito Hiroshi Kamada Tatsuro Nishi Pak H Chan 《Journal of cerebral blood flow and metabolism》2006,26(12):1479-1489
Recent studies have revealed that the phosphatidylinositol 3-kinase (PI3-K) pathway is involved in apoptotic cell death after experimental cerebral ischemia. The serine-threonine kinase, Akt, functions in the PI3-K pathway and prevents apoptosis by phosphorylation at Ser473 after a variety of cell death stimuli. After phosphorylation, activated Akt inactivates other apoptogenic factors, including glycogen synthase kinase-3beta (GSK3beta), thereby inhibiting cell death. However, the role of Akt/GSK3beta signaling in the delayed death of hippocampal neurons in the CA1 subregion after transient global cerebral ischemia (tGCI) has not been clarified. Transient global cerebral ischemia for 5 mins was induced by bilateral common carotid artery occlusion combined with hypotension. Western blot analysis showed a significant increase in phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) in the hippocampal CA1 subregion after tGCI. Immunohistochemistry showed that expression of phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) was markedly increased in the vulnerable CA1 subregion, but not in the ischemic-tolerant CA3 subregion. Double staining with phospho-GSK3beta (Ser9) and terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling showed different cellular distributions in the CA1 subregion 3 days after tGCI. Phosphorylation of Akt and GSK3beta was prevented by LY294002, a PI3-K inhibitor, which facilitated subsequent DNA fragmentation 3 days after tGCI. Moreover, transgenic rats that overexpress copper/zinc-superoxide dismutase, which is known to be neuroprotective against delayed hippocampal CA1 injury after tGCI, had enhanced and persistent phosphorylation of both Akt and GSK3beta after tGCI. These findings suggest that activation of the Akt/GSK3beta signaling pathway may mediate survival of vulnerable hippocampal CA1 neurons after tGCI. 相似文献
60.