全文获取类型
收费全文 | 261篇 |
免费 | 12篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 9篇 |
妇产科学 | 1篇 |
基础医学 | 20篇 |
口腔科学 | 7篇 |
临床医学 | 31篇 |
内科学 | 54篇 |
皮肤病学 | 5篇 |
神经病学 | 8篇 |
特种医学 | 35篇 |
外科学 | 16篇 |
综合类 | 54篇 |
预防医学 | 16篇 |
眼科学 | 4篇 |
药学 | 11篇 |
中国医学 | 1篇 |
肿瘤学 | 9篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2020年 | 2篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 9篇 |
2014年 | 5篇 |
2013年 | 9篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 9篇 |
2009年 | 20篇 |
2008年 | 6篇 |
2007年 | 11篇 |
2006年 | 5篇 |
2005年 | 3篇 |
2004年 | 10篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 13篇 |
1997年 | 19篇 |
1996年 | 10篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 7篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 10篇 |
1982年 | 9篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1958年 | 11篇 |
1957年 | 4篇 |
1952年 | 2篇 |
1951年 | 1篇 |
排序方式: 共有282条查询结果,搜索用时 15 毫秒
71.
Longacre TA; Foucar K; Crago S; Chen IM; Griffith B; Dressler L; McConnell TS; Duncan M; Gribble J 《Blood》1989,73(2):543-552
Morphologically distinct lymphoid cells with homogeneous, condensed chromatin and scant cytoplasm can be observed in large numbers in the bone marrow of children with a variety of hematologic and nonhematologic disorders. In some patients, these cells may account for greater than 50% of the bone marrow cells, creating a picture that can be confused with acute lymphoblastic leukemia (ALL) or metastatic tumor. Although originally called hematogones (HGs), a variety of other names have been proposed for these unique cells. The clinical significance of expanded HGs has not been resolved, and the biologic features of these cells are incompletely described. In this study, we correlate the clinical, morphologic, cytochemical, flow cytometric, molecular, and cytogenetic properties of bone marrow samples from 12 children with substantial numbers of HGs (range 8% to 55% of bone marrow cells). Diagnoses in these patients included anemia, four; neutropenia, one; anemia and neutropenia, one; idiopathic thrombocytopenic purpura, two; retinoblastoma, two; Ewing's sarcoma, one; and germ cell tumor, one. Flow cytometric analyses of bone marrow cells demonstrated a spectrum extending from early B-cell precursors (CD10+, CD19+, TdT+, HLA-Dr+) to mature surface immunoglobulin-bearing B cells in these patients, corroborating our morphologic impression of HGs, intermediate forms, and mature lymphocytes. DNA content was normal, and no clonal abnormality was identified by either cytogenetic or immunoglobulin and T-cell receptor (TCR) gene rearrangement studies. Follow-up ranged from 3 months to 3 years. None of the patients has developed acute leukemia or bone marrow involvement by solid tumor. The possible role of HGs in immune recovery and hematopoiesis is presented. 相似文献
72.
Proteolytic inactivation of human factor VIII procoagulant protein by activated human protein C and its analogy with factor V 总被引:21,自引:1,他引:21
Purified human factor VIII procoagulant protein (VIII:C) was treated with purified human activated protein C (APC) and the loss of VIII:C activity correlated with proteolysis of the VIII:C polypeptides. APC proteolyzed all VIII:C polypeptides with mol wt = 92,000 or greater, but not the doublet at mol wt = 79-80,000. These results and our previous thrombin activation studies of purified VIII:C, are analogous with similar studies of factor V and form the basis for the following hypothesis: activated VIII:C consists of heavy and light chain polypeptides [mol wt = 92,000 and mol wt = 79-80,000 (or 71-72,000), respectively] which are similar in Mr to the heavy and light chains of activated factor V. Thrombin activates VIII:C and V by generating these polypeptide chains from larger precursors and APC inactivates both molecules by cleavage at a site located in the heavy chain region of activated VIII:C and V. 相似文献
73.
74.
Takahashi H; Handa M; Watanabe K; Ando Y; Nagayama R; Hattori A; Shibata A; Federici AB; Ruggeri ZM; Zimmerman TS 《Blood》1984,64(6):1254-1262
We studied four patients who showed aggregation of platelets in platelet-rich plasma at lower concentrations of ristocetin than those required for normal platelet-rich plasma and who demonstrated an increased capacity of the platelets to bind normal von Willebrand factor. The four patients were from two Japanese families. Platelets from one family aggregated spontaneously in vitro, and platelets from both families aggregated upon the addition of normal plasma and cryoprecipitate, in the absence of ristocetin or other agonists. Analysis of the multimeric composition of von Willebrand factor by sodium dodecyl sulfate-agarose gel electrophoresis revealed a decrease in large multimers or a decrease in both large and intermediate multimers in plasma, but normal multimers in platelets. 1-Deamino-[8-D- arginine]-vasopressin caused by an immediate appearance of larger multimers in plasma, followed by the rapid disappearance of these multimers from circulating plasma. Analysis of platelet membrane glycoproteins from the patients showed that there were two distinct bands in the glycoprotein I region; one migrated in a slower region and the other in a faster region than normal glycoprotein Ib. We suggest that the platelet receptor abnormality in these patients is related to this abnormality of glycoprotein Ib. 相似文献
75.
Despite the use of HLA-matched platelets for alloimmunized recipients, transfusion failures occur. In order to reduce these failures, we investigated the use of a radiolabeled antiglobulin technique for platelet crossmatching. The principle of the test is that of an indirect Coombs test using 125I labeled goat anti-human IgG. Incompatibility is determined by calculating a radioactivity antiglobulin test (RAGT) index. Using this technique, we performed 89 crossmatches on 19 leukemic or aplastic patients who were refractory to random donor platelets and receiving varying degrees of HLA-matched platelets. Effectiveness of the transfusion was assessed from the posttransfusion corrected platelet count increment (CCI) determined at 1 and 20 hr. When the RAGT index was 1.9 or less, the mean CCI at 1 lhr was 17,570 +/- 7003/cu mm, n = 55. When the RAGT index was 2.0 or greater, the mean CCI was 4237 +/- 4100/cu mm, n = 34. At 20 hr when the RAGT index was 1.9 or less, the mean CCI was 8722 +/- 3143/cu mm, n = 33, and when the index was 2.0 or greater, the mean CCI was 571 +/- 1286/cu mm, n = 23. Using this technique, one false negative resulted. Nine positive crossmatches with good increments at 1 hr were found; at 20 hr, however, the survival of these units was zero. These data suggest that this method is a useful adjunct in the selection of platelets in the refractory patient. 相似文献
76.
Background
Obesity is a global epidemic with important health care and financial implications. The cold pressor test (CPT) which is considered to be a sympathy-excitatory manoeuvre is a simple, noninvasive and validated test. The objective of this study was to assess and compare the cardiovascular response to cold pressor test in non-obese and obese healthy adults.Methods
The study included 400 subjects, of which the study group included 200 adults who had body mass index (BMI) of more than 30 Kg/m,2 and 200 non-obese adults were enrolled as controls with BMI less than 25 kg/m2. The study was conducted for a period of two months. CPT was used to assess cardiac response to acute cold exposure in the present study. Baseline systolic and diastolic blood pressure recording was done using mercury sphygmomanometer during resting condition and following cold pressor test. The results were expressed as mean, standard deviation, and data were analyzed using ANOVA test. P < 0.05 was considered statistically significant.Results
The mean change in systolic blood pressure before and after cold pressor test (CPT) was less in obese (7.12 ± 5.28) as compared to non-obese subjects (10.38 ±6.35). This was statistically significant which indicates impaired sympathetic function in otherwise healthy obese.Conclusion
The study concluded that blood pressure response to cold pressor test was reduced in obese compared to non-obese subjects indicating reduced sympathetic activity in healthy obese adults. 相似文献77.
VS Gurunadh A Banarji S Patyal TS Ahluwalia AK Upadhyay Col M Bhadauria 《Medical Journal Armed Forces India》2010
Background: Proliferative vitreo-retinopathy (PVR) is the most common cause of failed repair of a primary rhegmatogenous retinal detachment (RRD). The success rates for the surgery of complicated RRD has doubled with improved vitreous techniques from 35-40% to approximately 65-75% at six months. However, despite these advances, recurrent vitreo-retinal traction leads to re-detachment in more than one-fourths of the initially successful cases. The use of adjunctive treatments to prevent cellular proliferation holds promise for the prevention of PVR or recurrences after surgery. One focus has been on the use of intra-vitreal antimetabolites to prevent the occurrence of PVR. 相似文献
78.
79.
80.
Identification of BRCA1 missense substitutions that confer partial functional activity: potential moderate risk variants? 下载免费PDF全文