全文获取类型
收费全文 | 1410462篇 |
免费 | 113529篇 |
国内免费 | 3332篇 |
专业分类
耳鼻咽喉 | 18361篇 |
儿科学 | 46546篇 |
妇产科学 | 41044篇 |
基础医学 | 200722篇 |
口腔科学 | 37694篇 |
临床医学 | 125981篇 |
内科学 | 284303篇 |
皮肤病学 | 33353篇 |
神经病学 | 116845篇 |
特种医学 | 53829篇 |
外国民族医学 | 464篇 |
外科学 | 210502篇 |
综合类 | 32754篇 |
现状与发展 | 3篇 |
一般理论 | 487篇 |
预防医学 | 109979篇 |
眼科学 | 31489篇 |
药学 | 98487篇 |
1篇 | |
中国医学 | 3348篇 |
肿瘤学 | 81131篇 |
出版年
2021年 | 10843篇 |
2019年 | 11662篇 |
2018年 | 16568篇 |
2017年 | 12665篇 |
2016年 | 14254篇 |
2015年 | 15999篇 |
2014年 | 22550篇 |
2013年 | 33381篇 |
2012年 | 45369篇 |
2011年 | 47907篇 |
2010年 | 28150篇 |
2009年 | 27040篇 |
2008年 | 44302篇 |
2007年 | 46805篇 |
2006年 | 47373篇 |
2005年 | 45841篇 |
2004年 | 43734篇 |
2003年 | 41682篇 |
2002年 | 40185篇 |
2001年 | 72998篇 |
2000年 | 74523篇 |
1999年 | 61555篇 |
1998年 | 16988篇 |
1997年 | 15430篇 |
1996年 | 15581篇 |
1995年 | 14789篇 |
1994年 | 13396篇 |
1993年 | 12583篇 |
1992年 | 45843篇 |
1991年 | 43477篇 |
1990年 | 41487篇 |
1989年 | 39551篇 |
1988年 | 36178篇 |
1987年 | 35351篇 |
1986年 | 32860篇 |
1985年 | 31277篇 |
1984年 | 23823篇 |
1983年 | 20023篇 |
1982年 | 12207篇 |
1981年 | 10779篇 |
1979年 | 20700篇 |
1978年 | 14576篇 |
1977年 | 12084篇 |
1976年 | 11364篇 |
1975年 | 11619篇 |
1974年 | 13988篇 |
1973年 | 13533篇 |
1972年 | 12633篇 |
1971年 | 11469篇 |
1970年 | 10910篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Hugo Maia Julio Casoy Tania Correia Luís Freitas Kleber Pimentel Célia Athayde Elsimar Coutinho 《Gynecological endocrinology》2006,22(10):547-551
OBJECTIVES: To determine whether aromatase expression in the eutopic endometrium and adenomyotic foci is affected by previous use of oral contraceptives containing gestodene, and to determine whether changes in cyclooxygenase-2 (COX-2) expression occur in adenomyosis during the menstrual cycle. PATIENT AND METHODS: This was a retrospective cohort study carried out in paraffin-embedded endometrial tissue obtained from patients with a histological diagnosis of adenomyosis obtained during the proliferative (n = 25) and luteal (n = 10) phases of the menstrual cycle and following the use of continuous oral contraception with gestodene/ethinyl estradiol (n = 7). COX-2 and aromatase expression were measured in both eutopic endometrium and adenomyotic foci using immunohistochemical methods. RESULTS: Aromatase expression was detected in 80% of the endometrial slices by immunohistochemistry. In positive cases, aromatase was mainly detected in the stromal cells of the eutopic endometrium, whereas in the adenomyotic foci this expression was negative in the majority of the cases. Oral contraceptives containing gestodene, on the other hand, were effective in suppressing aromatase expression in both eutopic and ectopic endometrium. COX-2 expression was detected by immunohistochemistry in the glandular epithelium of both eutopic endometrium and adenomyotic foci and there were no significant changes in its intensity throughout the menstrual cycle. CONCLUSION: Aromatase expression in the eutopic endometrium and adenomyotic foci is suppressed by oral contraceptives containing gestodene. Increased aromatase activity may be responsible for the persistent COX-2 expression during the luteal phase. 相似文献
72.
C G Arruda J M Aldrighi L A Bortolotto I N Alecrin J A F Ramires 《Gynecological endocrinology》2006,22(10):557-563
BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate. 相似文献
73.
The aim of our study was to determine the incidence, timing, and severity of vaginal stenosis in patients with carcinoma of the cervix who had received pelvic and/or vaginal radiotherapy as part of their treatment. We also sought to determine if there were any predisposing factors for the development of stenosis. A retrospective chart review was undertaken for all the patients diagnosed with carcinoma of the cervix between January 1, 1990, and December 31, 2000 and treated with pelvic and/or vaginal radiation at Westmead Hospital. Since January 1, 1990, data regarding vaginal stenosis has been prospectively recorded on all the patients. Data collected included patient demographics, stage of disease, treatments administered, and incidence, timing, and severity of vaginal stenosis. One hundred and eighty-eight patients were treated. Mean age was 58.6 years. Thirteen percent of patients had stage IB disease, 45% had stage II disease, 39.5% had stage III disease, and 1.5% had stage IV disease. One hundred and seventy-nine patients returned for follow-up, and data regarding vaginal toxicity were available in 98%. Twenty-seven percent had grade 1 toxicity (partial stenosis or shortening but not complete occlusion), and 11% had grade 2 (complete occlusion). Stenosis of any grade was noted at a mean of 9.6 months and median of 7.5 months (range, 26 days-5.6 years) from completion of treatment. The only prognostic factor associated with increased risk of stenosis was age greater than 50 years (odds ratio 2.26). Vaginal stenosis is a common complication of pelvic and vaginal radiotherapy, occurring in 38% of patients. Stenosis occurs most often in the first year after treatment. Patients over the age of 50 are most at risk. 相似文献
74.
75.
76.
In einer clusteranalytischen Untersuchung mit 137 Patienten, die einen Parasuizid verübt hatten, wurden 6 Subgruppen unter Berücksichtigung der Klassifikationsvariable “suicide intent” isoliert. Es wurde die Hypothese geprüft, dass sich sowohl die Motivstrukturen als auch die Raten an wiederholten Parasuiziden in Abh?ngigkeit der Clusterl?sung bedeutsam voneinander unterscheiden. Die Ergebnisse unterstützen die Annahme einer zunehmenden Ausdifferenzierung der interpersonell orientierten Motivstrukturen mit sinkendem bzw. einer Einengung der Motivstruktur auf den Todeswunsch mit steigendem “suicide intent”. Es wurden folgende Subgruppen differenziert: eine Suizid-Hochrisikogruppe mit ausschlie?licher Todesintention und -motivation, 2 moderate Suizid-Risikogruppen mit hoher Todesintention und leichten Tendenzen zu interpersoneller Motivation, eine Subgruppe, gekennzeichnet durch eine manipulativ/strategisch orientierte Motivstruktur und auff?llig h?ufigen Parasuizidwiederholungen, eine Subgruppe mit vorrangig appellativ orientierten Motiven, Kontrollverlust und vergleichsweise seltenen Parasuizidwiederholungen und eine Subgruppe mit ambivalenter Motivstruktur (interpersonell und todesorientiert). 相似文献
77.
78.
79.
Malignant tumors of the bones 总被引:2,自引:0,他引:2
D C Dahlin 《La Chirurgia degli Organi di Movimento》1988,73(3):185-186
80.
B A Thornhill H T Morehouse J C Hoffman-Tretin 《Critical reviews in diagnostic imaging》1988,28(1):1-22
Computed tomography (CT) is currently the imaging modality of choice for assessing the morphology of the adrenal glands in adult patients. Much useful information can be gained using CT in disease processes which primarily involve one or both of the adrenal glands, such as adenomas, as well as in entities which secondarily affect the adrenals, such as pituitary or metastatic disease. The size and configuration of the glands can be readily determined, and masses may be detected. We discuss CT of normal and abnormal adrenal glands with sonographic (US) and pathological correlation, when available. Entities which may mimic adrenal abnormalities are emphasized. Relative advantages of US over CT in the pediatric patient are discussed. 相似文献