全文获取类型
收费全文 | 168766篇 |
免费 | 6537篇 |
国内免费 | 370篇 |
专业分类
耳鼻咽喉 | 2229篇 |
儿科学 | 4840篇 |
妇产科学 | 4039篇 |
基础医学 | 24191篇 |
口腔科学 | 5483篇 |
临床医学 | 9691篇 |
内科学 | 37332篇 |
皮肤病学 | 4672篇 |
神经病学 | 13572篇 |
特种医学 | 4091篇 |
外国民族医学 | 1篇 |
外科学 | 19378篇 |
综合类 | 806篇 |
一般理论 | 26篇 |
预防医学 | 20178篇 |
眼科学 | 4388篇 |
药学 | 13188篇 |
中国医学 | 692篇 |
肿瘤学 | 6876篇 |
出版年
2023年 | 834篇 |
2022年 | 768篇 |
2021年 | 2772篇 |
2020年 | 1565篇 |
2019年 | 3136篇 |
2018年 | 5023篇 |
2017年 | 3130篇 |
2016年 | 3129篇 |
2015年 | 3470篇 |
2014年 | 4023篇 |
2013年 | 6061篇 |
2012年 | 10247篇 |
2011年 | 10885篇 |
2010年 | 5473篇 |
2009年 | 4099篇 |
2008年 | 8882篇 |
2007年 | 9515篇 |
2006年 | 9109篇 |
2005年 | 8724篇 |
2004年 | 8079篇 |
2003年 | 7569篇 |
2002年 | 7199篇 |
2001年 | 5017篇 |
2000年 | 5562篇 |
1999年 | 4251篇 |
1998年 | 819篇 |
1992年 | 2281篇 |
1991年 | 2041篇 |
1990年 | 2018篇 |
1989年 | 1732篇 |
1988年 | 1628篇 |
1987年 | 1536篇 |
1986年 | 1586篇 |
1985年 | 1461篇 |
1984年 | 1051篇 |
1983年 | 907篇 |
1979年 | 1217篇 |
1978年 | 807篇 |
1977年 | 784篇 |
1976年 | 747篇 |
1975年 | 882篇 |
1974年 | 1130篇 |
1973年 | 1177篇 |
1972年 | 1125篇 |
1971年 | 1087篇 |
1970年 | 1013篇 |
1969年 | 1087篇 |
1968年 | 1112篇 |
1967年 | 983篇 |
1966年 | 884篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
81.
Prospective study of antigenemia,plasma viremia and lymphocytic viremia in HIV-infected hemophiliacs
S. Melón Garcia M. de Oña Navarro C. Rodriguez Pinto M. Fernández Urgellés A. Martinez Gutierrez P. de la Iglesia F. J. Mendez García 《European journal of clinical microbiology & infectious diseases》1995,14(5):400-405
A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05). 相似文献
82.
P Bálványossy 《Der Unfallchirurg》1990,93(1):27-31
Anatomic dissection of 220 cadaver shoulders was performed to find out more about the static stabilizers of the shoulder joint. The static stabilizers, i.e. the glenohumeral ligaments, were always found to be present and strong in healthy shoulders. It was revealed that in anatomic preparations with all the organs removal except the synovial capsule, the capsule ligaments completely stabilized the joint. Anterior dislocation at 45 degrees of abduction was prevented by the superior and medial glenohumeral ligaments, while at 90 degrees of abduction the inferior glenohumeral ligament prevented dislocation. When anterior dislocation has occurred even the coracohumeral ligament must be ruptured. A new finding recorded is that the glenoid labrum is the origin of the inferior glenohumeral ligament and not a triangular static organ enlarging the socket and having a similar function to the menisci in the knee. This ligament is the most important ventral stabilizer of the humeral joint. With the conventional arthrotomy technique the medial and inferior ligaments are immediately cut through and therefore cannot be seen. The inferior glenohumeral ligament must be reconstructed in cases of anterior recurrent dislocation. 相似文献
83.
A series of N-(phosphonoacetyl)-dipeptide derivatives was synthesized for pharmacological testing as antihypertensive compounds. Several of these compounds demonstrated a moderate antihypertensive effect in Wistar spontaneous hypertensive rats (SHR) with p.o. dosing. ACE inhibition by the compounds was studied using ACE from rat plasma and lung. Inhibitors containing esterified C-termini are pro-drugs and showed activity only for plasma ACE. 相似文献
84.
P Bálványossy K Dévay L Alf?ldi 《Magyar traumatológia, orthopaedia és helyreállító sebészet》1990,33(2):140-141
Authors describe a case of isolated posttraumatic neuropraxy of the musculocutaneous nerve. With the presentation of this very rare case attention is called, based on literary date, to the fact that the above injury can be mixed with the distal tendon rupture of the biceps. 相似文献
85.
M. Villaplana A. García Ayala M. P. García Hernández B. Agulleiro 《Anatomy and embryology》1996,193(5):441-452
The cell organization of the pituitary gland and the relationship between neurohypophysis and adenohypophysis in the early developmental stages of the gilthead sea bream, Sparus aurata, were studied by electron microscopy. In newly hatched larvae, the pituitary gland was embedded in the ventral floor of the diencephalon and separated from the hypothalamus by a continuous basal lamina. Elongated mesenchymal cells next to the ventral surface were observed. At this stage, there was no neurohypophysis and the adenohypophysis consisted of undifferentiated endocrine cells with small scarce secretory granules and a few stellate cells, with no distinctive zonation. An incipient neurohypophysis was present in 1-day-old larvae. The first evagination of the neurohypophysis into the adenohypophysis were observed in 2-day-old larvae and developed progressively with age, being deeper in the caudal zone. Two regions in the adenohypophysis, one anterior — the presumptive pars distalis — and one posterior — the presumptive pars intermedia — were found in 2-day-old larvae. Three regions (rostral and proximal pars distalis and pars intermedia) were clearly distinguishable in 4-day-old larvae. The ultrastructural features of the pituitary endocrine cells varied during gland differentiation, with the secretory granules gradually increasing in number and size, accompanying organelle development. Nevertheless, even in the oldest larvae studied (65 days), undifferentiated cells similar to those in the earliest stages were observed. The first blood vessels appeared in the neurohypophysis around 16 days after hatching. During early development, the pituitary gland progressively emerged from the ventral floor of the brain. By 16 days, the principal pattern of the pituitary gland architecture appeared to be established. 相似文献
86.
87.
88.
Almir Moojen Nácul Andrea Prestes Nácul Antônio Greca de Born 《Aesthetic plastic surgery》1998,22(6):444-450
This research presents reports of cases where a biocompatible and alloplastic biomaterial—Bioplastique—was used, associated
with conventional plastic surgery or as a complement to it, with the aim of achieving a better final aesthetic result. Four
cases are presented where Bioplastique was used in association with rhytidoplasty, rhinoplasty, and other surgical techniques.
This material has shown itself to be appropriate to complement surgery; achieving a final result which would not be possible
without any resort to a complement or any other hard procedure by the surgeon and is not more traumatic for the patient. 相似文献
89.
A study of 52 middle-aged males with essential hypertension, unaccompanied by cardiovascular disorders, is reported. The patients were divided into 2 groups with respect to the type of treatment they received: 30 patients on beta-adrenoblockers and 22 patients on methyldopa. The patients were treated continuously for 2 years under one-dimensional echocardiographic control. The greatest drop in arterial blood pressure and ventricular septum thickness was seen within the first 6 months of treatment, while posterior-wall hypertrophy disappeared altogether. Although there was no further drop in blood pressure after 6 months, the thickness of the ventricular septum remained reduced for at least 2 years. Regression of left-ventricular hypertrophy was not accompanied with any deterioration of left-ventricular performance, nor was it related to additional use of vasodilators. 相似文献
90.
Tumor recurrence in prostatic urethra following simultaneous resection of bladder tumor and prostate 总被引:4,自引:0,他引:4
A comparative retrospective study was performed on 100 patients who had undergone transurethral resection of a superficial bladder tumor (Ta-Tl) with no associated carcinoma in situ (group 1) and 100 patients who had undergone simultaneous transurethral resection of a superficial bladder tumor (Ta-Tl), with no associated carcinoma in situ, and benign prostatic hyperplasia (group II). Evaluation of the recurrences of prostatic urethral tumors in both groups showed that they appeared in 10 patients (12 recurrences) in group I and 10 patients (14 recurrences) in group II (p = not significant). These data enabled us to rule out the influence of simultaneous transurethral resection in cases of recurrences of prostatic urethral tumors. 相似文献