全文获取类型
收费全文 | 118163篇 |
免费 | 12303篇 |
国内免费 | 3884篇 |
专业分类
耳鼻咽喉 | 1135篇 |
儿科学 | 2614篇 |
妇产科学 | 1631篇 |
基础医学 | 11169篇 |
口腔科学 | 2367篇 |
临床医学 | 15264篇 |
内科学 | 14161篇 |
皮肤病学 | 1390篇 |
神经病学 | 4761篇 |
特种医学 | 4238篇 |
外国民族医学 | 1篇 |
外科学 | 12320篇 |
综合类 | 21773篇 |
现状与发展 | 15篇 |
一般理论 | 29篇 |
预防医学 | 14138篇 |
眼科学 | 1285篇 |
药学 | 12705篇 |
84篇 | |
中国医学 | 7527篇 |
肿瘤学 | 5743篇 |
出版年
2024年 | 435篇 |
2023年 | 1111篇 |
2022年 | 2677篇 |
2021年 | 3654篇 |
2020年 | 2896篇 |
2019年 | 2110篇 |
2018年 | 2314篇 |
2017年 | 2590篇 |
2016年 | 2247篇 |
2015年 | 3735篇 |
2014年 | 4845篇 |
2013年 | 6283篇 |
2012年 | 8928篇 |
2011年 | 9219篇 |
2010年 | 7898篇 |
2009年 | 6970篇 |
2008年 | 7922篇 |
2007年 | 7536篇 |
2006年 | 6853篇 |
2005年 | 5838篇 |
2004年 | 4553篇 |
2003年 | 3885篇 |
2002年 | 3407篇 |
2001年 | 3101篇 |
2000年 | 2712篇 |
1999年 | 1738篇 |
1998年 | 690篇 |
1997年 | 589篇 |
1996年 | 505篇 |
1995年 | 520篇 |
1994年 | 501篇 |
1993年 | 437篇 |
1992年 | 1127篇 |
1991年 | 1065篇 |
1990年 | 1049篇 |
1989年 | 972篇 |
1988年 | 885篇 |
1987年 | 920篇 |
1986年 | 880篇 |
1985年 | 908篇 |
1984年 | 713篇 |
1983年 | 613篇 |
1982年 | 435篇 |
1981年 | 349篇 |
1980年 | 366篇 |
1979年 | 579篇 |
1978年 | 443篇 |
1977年 | 363篇 |
1976年 | 371篇 |
1974年 | 379篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
101.
Increased dietary NaCl intake increases the responsiveness of central nervous system alpha 2-adrenoceptors which regulate the neural control of renal function in spontaneously hypertensive rats (SHR) but not Wistar-Kyoto (WKY) normotensive rats. The borderline hypertensive rat (BHR) is the first filial offspring of the SHR and the WKY. With increased dietary NaCl intake, the BHR develops hypertension and expresses other characteristics of the hypertensive SHR parent. This investigation sought to determine whether increased dietary NaCl intake in the BHR enhances the responsiveness of central nervous system alpha 2-adrenoceptors. Six weeks of increased dietary NaCl intake (8% versus 1% NaCl) in BHR augmented the depressor, bradycardic, renal sympatho-inhibitory and diuretic responses to intracerebroventricular administration of graded doses (5, 25 and 125 micrograms) of the alpha 2-adrenoceptor agonist, guanabenz. The results suggest that the potential for an increased responsiveness of central nervous system alpha 2-adrenoceptors is genetically transmitted to the BHR by the SHR and may be exposed in the BHR by increased dietary NaCl intake. 相似文献
102.
We conducted a survey using an unstructured, then a structured, questionnaire to determine the attitudes of 78 postfellowship anaesthetists to the Basic Sciences component of the part I examination for the FRCA. Seventy-two per cent replied. These anaesthetists felt that about 65% of the basic science syllabus was essential to the understanding and practice of everyday anaesthesia, but there was varying opinion as to the importance of specific topics. Cardiovascular, respiratory, central nervous system and renal physiology were all regarded as essential, as was the pharmacology of anaesthetic drugs. Topics regarded as irrelevant included biochemistry, endocrinology, membrane theory and immunology. Paradoxically, there were many topics which anaesthetists regarded as essential but on which they were unable to give a tutorial. There was little difference between the responses of consultants and trainees. This survey may help to identify a core syllabus on which the majority of anaesthetists agree but also suggests that the current syllabus is overloaded with detail that has no place in clinical practice. 相似文献
103.
104.
B Reichman M Markman T Hakes A Budnick S Rubin W Jones L Almadrones J L Lewis W Hoskins 《Gynecologic oncology》1991,43(2):159-163
Cisplatin is one of the most active single agents in the treatment of advanced cancer of the cervix. The concurrent administration of the nephroprotective agent, sodium thiosulfate, has enabled exploitation of the therapeutic potential of cisplatin. To explore the role of cisplatin dose intensity in the treatment of patients with cancer of the uterine cervix, patients with persistent/recurrent measurable disease were treated with cisplatin at 200 mg/m2 as a 2-hr infusion with sodium thiosulfate given at 3.3 g/m2 1 hr prior to cisplatin and 6.6 g/m2 during the cisplatin infusion. Treatment was repeated monthly. Due to the known cumulative toxicity of cisplatin, treatment beyond two cycles (400 mg/m2) was given only to those patients who had at least demonstrated a PR. Audiologic evaluation was done prior to each cycle of treatment. Eleven patients were entered with a median age of 43 years (range, 25-57), a median KPS of 80% (range, 60-90%), and nine epidermoid and two adenocarcinoma, and all patients had received previous pelvic irradiation. Twenty-eight cycles of treatment were given: 1, five cycles; 3, three cycles; 7, two cycles. No greater than or equal to 3+ hematologic, neurologic, or renal toxicity was demonstrated. Ototoxicity was demonstrated in the mild to moderate hearing loss range (3000-8000 Hz). The greatest threshold shift occurred after the first course of cisplatin. There were three PRs with a maximum duration of 4 months. Due to the significant toxicities encountered, the low response rate, and the limited duration of responses, this trial was closed early to accrual. 相似文献
105.
Alun Jones 《Journal of advanced nursing》1997,25(2):238-244
This paper explores one facet of a therapeutic relationship with a woman suffering from inoperable cervical cancer. The psychotherapy sessions were conducted in both hospital and the family home and continued on a weekly basis until final termaination immediately prior to the woman's death. Through a ‘suspense structure’ case study narrative, the writer, a nurse psychotherapist, describes the way in which the humanities art and poetry can provide a means through which to understand seemingly incomprehensible feelings related to reviewing past events as a preparation for death. While no explict critique is made of the twin psychoanalytical concept of transference and countertransference, the occurrence is woven into the text. The essential nature of clinical supervision is illustrated in context. The author proposes that engagement in a therapeutic relationship with a dying person presents the worker with parallel struggles manifesting in elementary feelings which require discernment. The central recommendation of this paper is that the rich symbolic language and metaphors, redolent in art and poetry, be harnessed as a potent therapeutic and metaphors, redolent in art and poetry, be harnessed as a potent therapeutic tool. Throughout the discussion, the terms counseling and psychotherapy are used interchangeably. 相似文献
106.
Jill Macleod Clark PhD BSc RGN Jill Maben MSc BA RGN Karen Jones BA RHV RGN 《Journal of advanced nursing》1997,26(1):161-168
This is the first of two papers which address aspects of the findings of a large scale study commissioned by the English National Board which set out to examine the impact of Project 2000 on perceptions of the philosophy and practice of nursing. The findings presented here suggest that there have been fundamental shifts in perceptions of the nature and discipline of nursing. Students and diplomates of the course perceive themselves as knowledgeable doers, with their practice well grounded in theory and research. They value the interpersonal skills teaching and place the patient firmly at the centre of care delivery, viewing the patient holistically and being prepared to be fierce patient advocates where necessary. It is difficult to determine the extent to which these shifts can be attributed to the Project 2000 course, although the Project 2000 approach to education appears to be an important factor. 相似文献
107.
E Rechavia A R Galassi L I Araujo P Halson A A Lammertsma T Jones J P Lavender A Maseri 《European journal of nuclear medicine》1992,19(12):1044-1049
To relate technetium-99m 2-methoxy-isobutyl-isonitrile (99mTc-MIBI) uptake to regional myocardial blood flow (rMBF), 99mTc-MIBI single photon emission tomography (SPET) and H2(15)O positron emission tomography (PET) scans were obtained at rest and after dipyridamole infusion in six patients with single vessel coronary artery disease. 99mTc-MIBI and H2(15)O data sets were created for each segment perfused by the stenotic vessel and for a normal reference area, assigning regions on the SPET tomograms to comparable regions on the PET by similar transaxial image reconstructions. All patients demonstrated post-dipyridamole 99mTc-MIBI perfusion defects in the territories supplied by the stenotic arteries. Resting rMBF in these regions was slightly lower than that in the normal areas (0.82 +/- 0.05 vs 0.90 +/- 0.09 ml/g/min, P = NS). A 43% +/- 14% reduction in 99mTc-MIBI activity in the area at risk was coupled with on average a 60% +/- 9% reduction in post-dipyridamole rMBF compared with control regions (0.98 +/- 0.08 vs 2.52 +/- 0.51 ml/g/min, P < 0.001). Thus, SPET assessment of 99mTc-MIBI uptake tends to underestimate the perfusion contrast between areas with normal and areas with low coronary vasodilatory reserve when compared to PET. However, these findings may still not affect the clinical usefulness of 99mTc-MIBI and more extensive studies are required to confirm these results in the clinical environment. 相似文献
108.
STUDY OBJECTIVE: To determine the increase in flow of a hydratable enlarging intravenous (IV) catheter in anesthetized patients. DESIGN: A randomized, nonblinded study, with standard Teflon IV catheters used as controls. SETTING: Operating room at a university medical center. PATIENTS: Thiry adult patients receiving general anesthesia for lower extremity surgery. INTERVENTIONS: An IV catheter was placed in the upper extremity, and flow measurements were made by measuring the time for infusion of 250 ml of normal saline within 1 minute after placement and at 1 hour after placement. MEASUREMENTS AND MAIN RESULTS: The enlarging catheters had a statistically significant average flow increase of 26% after 1 hour indwelling time. The standard Teflon catheters had no statistically significant change in flow after 1 hour. The percentage increase in flow for the enlarging catheters was not as great as previously seen in vitro. CONCLUSIONS: Flow through enlarging IV catheters placed in anesthetized patients increases after 1 hour. The percentage increase in flow is not as great as previously seen in vitro and may be due to skin, vein, and subcutaneous tissues preventing complete expansion. 相似文献
109.
Kristine Jones Ph.D. Paul Colson Ph.D. Elie Valencia J.D. Ezra Susser M.D. Dr.P.H. 《The Psychiatric quarterly》1994,65(4):243-256
The Critical Time Intervention Project is a three-year clinical trial which tests a time-limited, supportive intervention
to reduce recurrent homelessness among mentally ill men moving from a shelter to the community. Along with a comparison of
nights spent homeless and other outcomes, the evaluation of the Critical Time Intervention includes a comparison of the relative
costs of the intervention, compared to usual treatment. Such cost effectiveness analyses are difficult to perform and are
rarely applied to mental health treatments. This paper presents the general scheme of this analysis and discusses critical
issues in the construction and measurement of cost variables. Preliminary results which have implications for the cost analysis
are presented. 相似文献
110.