全文获取类型
收费全文 | 1108篇 |
免费 | 75篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 18篇 |
妇产科学 | 17篇 |
基础医学 | 115篇 |
口腔科学 | 19篇 |
临床医学 | 103篇 |
内科学 | 210篇 |
皮肤病学 | 25篇 |
神经病学 | 74篇 |
特种医学 | 160篇 |
外科学 | 284篇 |
综合类 | 20篇 |
预防医学 | 56篇 |
眼科学 | 6篇 |
药学 | 25篇 |
肿瘤学 | 63篇 |
出版年
2021年 | 8篇 |
2020年 | 15篇 |
2019年 | 11篇 |
2018年 | 20篇 |
2017年 | 11篇 |
2016年 | 15篇 |
2015年 | 20篇 |
2014年 | 21篇 |
2013年 | 50篇 |
2012年 | 25篇 |
2011年 | 33篇 |
2010年 | 34篇 |
2009年 | 43篇 |
2008年 | 33篇 |
2007年 | 55篇 |
2006年 | 37篇 |
2005年 | 43篇 |
2004年 | 23篇 |
2003年 | 25篇 |
2002年 | 22篇 |
2001年 | 31篇 |
2000年 | 31篇 |
1999年 | 33篇 |
1998年 | 60篇 |
1997年 | 53篇 |
1996年 | 26篇 |
1995年 | 27篇 |
1994年 | 15篇 |
1993年 | 18篇 |
1992年 | 17篇 |
1991年 | 19篇 |
1990年 | 15篇 |
1989年 | 27篇 |
1988年 | 30篇 |
1987年 | 30篇 |
1986年 | 36篇 |
1985年 | 33篇 |
1984年 | 23篇 |
1983年 | 23篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 11篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 10篇 |
1971年 | 4篇 |
1968年 | 5篇 |
1966年 | 8篇 |
排序方式: 共有1196条查询结果,搜索用时 31 毫秒
1.
R C Flanigan M F Ellison K M Butler L G Gomella J W McRoberts 《The Journal of urology》1986,136(1):35-37
There were 40 consecutive patients with recurrent or multiple superficial stage Ta or T1 transitional cell cancer assigned randomly to receive prophylactic thiotepa or mitomycin C intravesical chemotherapy. Patients received 8 weekly instillations followed by 22 monthly treatments of either 60 mg. thiotepa or 40 mg. mitomycin C. Of 25 patients randomized to receive mitomycin C 4 had recurrence in a total of 337 patient-months (1.19 per 100 patient-months), while disease recurred in 1 of 15 patients randomized to receive thiotepa who were followed for a total of 220 patient-months (0.45 per 100 patient-months). No significant difference in recurrence rate was noted for either drug group (p equals 0.18). Toxicity requiring cessation of therapy was observed in 7 patients (28 per cent) on mitomycin C and none on thiotepa. 相似文献
2.
Cloacal exstrophy, centered on the maldevelopment of the primitive streak mesoderm and cloacal membrane, results in bladder and intestinal exstrophy, omphalocele, gender confusion, and hindgut deformity. The surgical management and outcome of 10 of 14 survivors (1965 to 1988) are described. Genotypic males (6) were assigned male (2) or female (4) phenotype. Genotypic females (4) were unchanged. All had omphalocele closure in the newborn period. Two had loop stomas. Eight had end stomas (ileostomy [6], ileocolostomy [2]). Toddler and adolescent reconstruction differed in each. Early in the study, abdominoperineal pull-through failed in four patients, necessitating permanent stoma. Four patients had a stoma from the outset. Augmentation using colon remnant improved water loss and nutrition in two infants. Exstrophy turn-in for urinary reservoir was considered in all, but was impossible in three who required urinary diversion. Six patients had exstrophy turn-in and now void by clean intermittent catheterization (4), continent vesicostomy (1), and incontinent (1). Hindgut augmentation improved urinary capacity in two. Two genotypic-phenotypic males had penile lengthening. Four genotypic male-phenotypic females had early orchiectomy with subsequent clitoroplasty or vaginoplasty. Four genotypic-phenotypic females had clitoroplasty or vaginoplasty. Cloacal exstrophy is compatible with a useful life and sound psychologic development, but requires staged reconstruction with long-term support and follow-up. 相似文献
3.
Robert C. Flanigan Joseph H. Saiers Michael Wolf Eric H. Kraut Anthony Y. Smith Brent Blumenstein E. David Crawford 《Investigational new drugs》1994,12(2):147-149
Summary The Southwest Oncology Group (SWOG) studied the response rate and toxicity of merbarone (1,000 mg/m2 IV continuous infusion days 1–5, q 21 days) in patients with advanced metastatic renal cell carcinoma. Among 36 eligible patients, there was one partial response for a response rate of 3% (95% C.I. 0.1–15%). There were no mixed responses. There were no treatment related deaths or adverse drug reactions. Significant anemia, diarrhea, and hypercalcemia were observed. Mild to moderate degrees of malaise/fatigue/lethargy, dizziness/vertigo, hyperglycemia, creatinine increase, nausea, vomiting, weight loss, pedal edema, dyspnea, and granulocytopenia were noted. Merbarone does not have significant activity as a single agent in advanced renal cell carcinoma. 相似文献
4.
The failure of infarction and/or nephrectomy in stage IV renal cell cancer to influence survival or metastatic regression 总被引:1,自引:0,他引:1
R C Flanigan 《The Urologic clinics of North America》1987,14(4):757-762
The success of cancer therapy depends on the destruction of all viable cancer cells in the primary site, as well as in metastatic areas. Surgery alone can do little for the patient whose tumor has produced distant involvement except in those situations where surgical excision, radiotherapy, chemotherapy, or immunotherapy can be relied on to eradicate metastatic disease. Because of the paucity of systemic therapy for renal cell carcinoma, an aggressive surgical approach to the primary tumor is justifiable when all metastatic lesions can be excised or otherwise definitively treated and in experimental protocols in which adjuvant therapy of possible benefit can be combined with palliative nephrectomy. There is no evidence, however, in reported studies to suggest that routine palliative nephrectomy in patients who will not be offered adjuvant systemic therapy or radiation is beneficial. Such practice is also associated with a higher incidence of complications and mortality than is expected for resection of localized renal cell carcinoma. For these reasons, it is reasonable to recommend adjunctive nephrectomy only in certain selected instances, which include (1) the control of a patient's current symptoms related to the primary disease, for example, flank pain, hematuria, fever and toxicity, anemia, erythrocytosis, and hypercalcemia; (2) nephrectomy with the excision of a solitary metastasis; and (3) the patient who is willing to undergo experimental therapy, part of which involves removal of the primary tumor. 相似文献
5.
We used a quantitative immunoassay to examine the effects of human serum and immunoglobulins on neurofilament protein expression in cultures of chick spinal neurons. Compared with cultures grown in the presence of serum from healthy controls or patients with other neurologic disorders, ALS serum lowered the level of neurofilament proteins. Effects were similar with or without muscle-derived neurotrophic factors; there was no specificity for motor neurons. No neurotoxic activity was found in immunoglobulin fractions, and there was no evidence of circulating antibodies that might neutralize muscle-derived neurotrophic factors or induce cytolysis of spinal neurons. 相似文献
6.
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
7.
Asexual development of Cryptosporidium parvum within a differentiated human enterocyte cell line. 总被引:12,自引:9,他引:3
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Unremitting diarrhea with malabsorption is associated with Cryptosporidium parvum infection of the small intestine in patients with AIDS. The lack of a well-defined in vitro model of C. parvum infection has severely hampered research into the biology of cryptosporidial invasion of the host epithelial cell and development of new pharmacologic and immunologic therapies. The adherent human intestinal epithelial cell line HT29 when grown in glucose-free medium develops morphologic and functional characteristics of the small intestine enterocyte and was used to develop an in vitro model of infection. Cryptosporidium oocysts obtained from AIDS patients were applied to a monolayer of cloned, differentiated HT29.74 cells. Cells were fixed and stained to estimate the degree of parasite infection. Schizonts were easily distinguished from the host cell by light microscopy. Twenty-four hours after 10(5) oocysts were added to approximately 10(6) HT29.74 cells, Cryptosporidium infection rates varied from 50 to 120 schizonts per 1,000 cells. Among 14 different experiments, the mean infection rate was 91 (+/- 18) schizonts per 1,000 cells. Electron microscopy at 6 and 24 h confirmed intracellular localization and development of schizonts. The morphologic features of the cryptosporidial schizonts within HT29.74 cells, which included the presence of a dense band and feeder layer, were identical to those described during cryptosporidial infection of human enterocytes in patients with AIDS. Fewer schizonts were observed at 5 days and beyond. Infection of differentiated HT29.74 cells (62 and 65 schizonts per 1,000 cells at 24 and 72 h, respectively) was over five times more efficient than infection of undifferentiated HT29.74 cells (9 and 5 schizonts per 1,000 cells at 24 and 72 h, respectively). In vitro infection of differentiated HT29.74 cells will allow a better understanding of the mechanisms by which C. parvum infects the small intestinal epithelium and will allow a systematic evaluation of new therapeutic agents. 相似文献
8.
9.
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
10.
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