全文获取类型
收费全文 | 6065篇 |
免费 | 403篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 324篇 |
妇产科学 | 165篇 |
基础医学 | 760篇 |
口腔科学 | 51篇 |
临床医学 | 1298篇 |
内科学 | 801篇 |
皮肤病学 | 68篇 |
神经病学 | 475篇 |
特种医学 | 149篇 |
外科学 | 374篇 |
综合类 | 88篇 |
一般理论 | 16篇 |
预防医学 | 878篇 |
眼科学 | 95篇 |
药学 | 508篇 |
1篇 | |
中国医学 | 10篇 |
肿瘤学 | 374篇 |
出版年
2023年 | 24篇 |
2022年 | 37篇 |
2021年 | 59篇 |
2020年 | 41篇 |
2019年 | 111篇 |
2018年 | 123篇 |
2017年 | 85篇 |
2016年 | 103篇 |
2015年 | 99篇 |
2014年 | 132篇 |
2013年 | 285篇 |
2012年 | 425篇 |
2011年 | 446篇 |
2010年 | 253篇 |
2009年 | 162篇 |
2008年 | 417篇 |
2007年 | 428篇 |
2006年 | 401篇 |
2005年 | 443篇 |
2004年 | 408篇 |
2003年 | 367篇 |
2002年 | 415篇 |
2001年 | 33篇 |
2000年 | 43篇 |
1999年 | 34篇 |
1998年 | 87篇 |
1997年 | 82篇 |
1996年 | 61篇 |
1995年 | 69篇 |
1994年 | 64篇 |
1993年 | 56篇 |
1992年 | 36篇 |
1991年 | 32篇 |
1990年 | 35篇 |
1989年 | 26篇 |
1988年 | 27篇 |
1987年 | 21篇 |
1986年 | 27篇 |
1985年 | 35篇 |
1984年 | 51篇 |
1983年 | 38篇 |
1982年 | 72篇 |
1981年 | 42篇 |
1980年 | 39篇 |
1979年 | 29篇 |
1978年 | 32篇 |
1977年 | 25篇 |
1976年 | 23篇 |
1974年 | 20篇 |
1972年 | 16篇 |
排序方式: 共有6476条查询结果,搜索用时 15 毫秒
51.
We report a case of Waldenstr?m macroglobulinemia with trisomy 4 as the sole cytogenetic abnormality. Trisomy 4 has been reported previously in Waldenstr?m macroglobulinemia, but only in conjunction with multiple chromosomal aberrations. Trisomy 4 has been reported in other hematologic malignancies including acute myeloid and lymphoid leukemias. 相似文献
52.
53.
54.
Urinary IgA in IgA nephropathy and Henoch-Schoenlein purpura 总被引:1,自引:0,他引:1
John H. Galla Marilyn F. Spotswood Lynn A. Harrison Jiri Mestecky 《Journal of clinical immunology》1985,5(5):298-306
To determine the concentrations and molecular forms of urinary IgA in IgA nephropathy and Henoch-Schoenlein purpura, we studied 29 patients with these IgA-associated renal diseases (IgAN). Control groups comprised 10 patients with other diverse renal diseases and 11 healthy volunteers. Urinary IgA and IgG concentrations were higher in IgAN than in either control group and correlated positively with the serum creatinine concentration as well as the urinary protein excretion (P<0.01). However, IgA/IgG ratios did not differ among the three groups. Polymeric IgA (p-IgA) in the urine predominated only in normals; in IgAN and patients with other renal diseases, monomeric IgA (m-IgA) occurred almost exclusively. Serum IgA concentrations were generally normal in IgAN; four patients had concentrations greater than 500 mg/dl. Although the fraction of p-IgA in serum (median, 18%) was increased above normal (5–10%) in 13 of 16 (81%) subjects, neither the concentration of IgA or IgG nor the amount of p-IgA correlated with the serum creatinine concentration. These data suggest that the molecular form and concentration of urinary IgA are not discriminating for IgAN and are independent of these characteristics of serum IgA. 相似文献
55.
Richard S. Surwit Marilyn N. Bradner Cynthia H. Fenton Robert N. Pilon 《Psychophysiology》1978,15(4):320-323
The purpose of the present study was to assess the relationship between lateralization of body image and right versus left vasomotor activity. Fifteen right-handed female patients suffering from idiopathic Raynaud's disease demonstrated a relationship between the extent of right lateralization of body image and bilateral digital skin temperature during a controlled temperature stress test. In addition, subjects showing a reliable right side awareness demonstrated more unilateral vasospastic attacks in their right hand than their left hand white subjects showing no clear right lateralization by body image reported more left hand attacks than right hand attacks. These results were taken as consistent with previous work on the relationship between skin conductance and lateralization of body image. 相似文献
56.
Previously, our laboratory has shown that androgen receptors in the medial preoptic area (MPOA) and ventromedial nucleus (VMN) are necessary for copulation in male rats. The present study examined whether these receptors are required for other sociosexual behaviors. In Experiment 1, different regions of the VMN were implanted with the antiandrogen hydroxyflutamide (OHF). We found that implants located in anterodorsal portions of the VMN were more effective at inhibiting the restoration of copulation than implants in the posteroventral VMN. In Experiment 2, a second set of male rats was pretested for copulation and other sociosexual behaviors and was castrated. Experimental animals then received Silastic capsules filled with testosterone (T) plus intracranial (IC) implants filled with OHF to selectively block androgen receptors in either the MPOA or VMN. We found that androgen receptor blockade in the MPOA inhibited the restoration of copulation but had no effect on other sociosexual behaviors. OHF directed at the VMN inhibited the restoration of copulation and 50-kHz vocalizations but had no effect on scent marking. Two tests were used to assay sexual motivation: partner preference and conditioned place preference (CPP). Both methods revealed impairments in sexual motivation in the VMN group but not in animals receiving OHF in the MPOA. Taken together, these data suggest that androgen receptors in the MPOA are essential for copulatory performance, while androgen receptors in the VMN are important for copulation, sexual motivation, and androgen-dependent vocalizations. 相似文献
57.
Vaux KK Hudgins L Bird LM Roeder E Curry CJ Jones M Jones KL 《American journal of medical genetics. Part A》2005,(3):244-247
The Kabuki syndrome is a well-established pattern of human malformation with readily recognizable features, however the diagnosis is rarely made in the newborn period. The purpose of this study was to determine if there exists a neonatal phenotype for this disorder. We ascertained 16 infants evaluated in the first 28 days of life by a dysmorphologist who subsequently received the diagnosis of Kabuki syndrome. The average age of initial evaluation was 8 days and the average age of diagnosis was 2 years 6 months. Based on these findings, it is suggested that the distinctive clinical phenotype seen in older patients is also evident in the newborn period. 相似文献
58.
Marilyn Y. McGinnis Christopher P. Phelps Dwight M. Nance Bruce S. McEwen 《Physiology & behavior》1982,29(2):225-229
Retrochiasmatic frontolateral knife cuts (FLC) or sham operations (Sham) were performed with a Halasz-type knife. All animals were primed with estrogen plus 0.5 mg progesterone (P) and tested for lordosis both before and after surgery. Two weeks after the last test they received estradiol (E2) in Silastic capsules and were sacrificed 2 days later for determination of either nuclear estrogen receptors or cytosol progestin receptor binding in brain and pituitary (PIT). Rats which had received FLC showed significantly lower lordosis quotients relative to Shams, and relative to their own pre-surgery scores. Nuclear E2-receptor binding was significantly reduced in the hypothalamus (HYPO) following FLC, but not in preoptic area (POA) or PIT. No changes in cytosol P-receptor binding were observed in HYPO, POA or PIT following FLC. Our results suggest a positive correlation between the number of hypothalamic E2-receptors and the capacity to display lordosis, and emphasize the importance of anterolateral connections to the HYPO for the progesterone-induced facilitation of lordosis. 相似文献
59.
Previous studies demonstrated that the formamidine pesticide chlordimeform (CDM) reversibly inhibited prostaglandin biosynthesis and prevented the late (PG-mediated) phase of carrageenin-induced hind paw edema. This study emphasizes antagonism by CDM of the early (5HT and histamine-mediated) phase of carrageenin edema. CDM and cyproheptadine both antagonized paw edema induced by albumin (5HT and histamine-mediated) and by the direct injection of 5HT and histamine, whereas aspirin and the PG antagonist, SC-19220, were ineffective. As expected, cyproheptadine selectively reduced the early phase, whereas aspirin and SC-19220 selectively reduced the late phase of carrageenin-induced edema. These results are thus consistent with earlier studies demonstrating PG mediation of the late phase of carrageenin edema, and 5HT and histamine mediation of albumin edema and the early phase of carrageenin edema. In addition, they indicate that CDM possesses multiple acute anti-inflammatory, actions not exhibited by aspirin, by SC-19220 or by cyproheptadine alone. 相似文献
60.
Cell proliferation may be evaluated by various methods, including Ki-67 immunohistochemistry and measures of telomerase activity. Both methods would theoretically show comparable increases in a given case. To evaluate the relationship between these 2 markers of proliferation in aggressive mature B-cell lymphomas, 48 cases were studied. The study group included 5 cases of mantle cell lymphoma (MCL); 6 cases of Burkitt's/Burkitt's-like lymphoma (BL); 9 cases of follicular lymphoma, grade 3 (FLC); and 28 cases of diffuse large B-cell lymphoma (DLC). Telomerase activity was measured as total product generated (TPG) units, and TPG results for the aforementioned cases were compared to the TPG results for 10 cases of reactive follicular hyperplasia. An overlap in TPG scores between reactive cases and lymphoma cases was found. Significant differences in both log TPG (P = 0.0443) and Ki-67 (P = 0.0006) were seen in the different lymphoma types. A positive correlation between Ki-67 percentage and TPG score was identified in FLC (r = 0.9281; P = 0.0003), but a poor correlation between these 2 indicators was seen in the other lymphoma types. Cluster analysis identified distinct patterns for MCL, FLC, and BL, but heterogeneous patterns for DLC. Because increases in both Ki-67 proliferation and telomerase activity are reported in normal germinal centers (GCs), these tests were also evaluated for usefulness as markers of a GC cell phenotype. Among the FLC and DLC cases, features of a GC phenotype significantly correlated with increased Ki-67 percentage (P = 0.0152), but not with increased log TPG. An elevated log TPG correlated with CD10 expression, and elevated Ki-67 percentage correlated with both CD10 and BCL-6 expression. TPG level and Ki-67 percentage did not correlate with the presence of t(14;18) or BCL-2 protein expression. Although the proliferation patterns were fairly distinctive for MCL, FLC, and BL, these studies show that markers of cell proliferation do not by themselves,identify distinct subtypes of large cell lymphomas. With the exception of FLC, the tumors exhibited poor correlation between telomerase activity and Ki-67 proliferation index. These tests did show some correlation with expression of GC cell phenotypic markers, however. 相似文献