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排序方式: 共有801条查询结果,搜索用时 15 毫秒
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BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
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Rosenberg ZS; Jahss MH; Noto AM; Shereff MJ; Cheung Y; Frey CC; Norman A 《Radiology》1988,167(2):489-493
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture. 相似文献
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Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
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Tissue amyloid P component in normal human dermis is non-covalently associated with elastic fiber microfibrils 总被引:3,自引:0,他引:3
Tissue amyloid P component (TAP), a protein that crossreacts immunohistochemically with the normal plasma glycoprotein serum amyloid P component (SAP), is invariably associated with elastic fiber microfibrils in adult humans. We have investigated the nature of this association. Aliquots of minced, homogenized dermis, obtained following ethylenediamine tetraacetic acid (EDTA) separation of whole adult human skin, were extracted with different reagents, and the presence or absence of TAP in the pellet and in the supernatant following centrifugation was determined by SDS-PAGE and immunoblotting using anti-SAP antibodies. TAP was extractable from dermis using reagents which disrupt non-covalent bonds, including sodium dodecyl sulfate (SDS) and guanidine hydrochloride. TAP was not extracted by high molarity salt solutions, non-ionic detergents, or the reducing agents dithiothreitol and 2-mercaptoethanol. EDTA solution was similarly unsuccessful at eluting TAP from the dermal preparation, indicating that the association of TAP with elastic fiber microfibrils is not simply the result of Ca++-dependent binding. Collagenase solubilized some TAP, but this does not prove covalent linkage to elastic tissue of part of the TAP, because the apparent Mr of TAP extracted was identical to that of normal SAP subunits. We cannot completely exclude the possibility that a few subunits in each multimeric TAP molecule are covalently attached to the microfibrils. However, our findings that denaturing agents alone extracted most of the TAP from normal human dermis strongly suggest that the great majority of the dermal TAP is non-covalently bound to elastic fiber microfibrils. Thus TAP is not an integral constitutent of elastic fiber microfibrils. 相似文献
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Bilateral simultaneous tubal sextuplets: pregnancy after in-vitro fertilization--embryo transfer following salpingectomy 总被引:2,自引:1,他引:2
The presence of a damaged tube has been suggested in recent studies to have
a negative effect on in-vitro fertilization (IVF) outcome. Performing
bilateral salpingectomy prior to IVF to maximize pregnancy rates may also
result in unnecessary surgery. This case is also an example of the
occurrence of interstitial pregnancy after salpingectomy. This unusual type
of ectopic pregnancy must be kept in mind when evaluating a patient
suspected of a possible early abnormal gestation after assisted
reproductive technolologies.
相似文献