全文获取类型
收费全文 | 3265篇 |
免费 | 167篇 |
国内免费 | 34篇 |
学科分类
医药卫生 | 3466篇 |
出版年
2023年 | 31篇 |
2022年 | 56篇 |
2021年 | 114篇 |
2020年 | 87篇 |
2019年 | 103篇 |
2018年 | 127篇 |
2017年 | 85篇 |
2016年 | 98篇 |
2015年 | 101篇 |
2014年 | 129篇 |
2013年 | 165篇 |
2012年 | 259篇 |
2011年 | 300篇 |
2010年 | 144篇 |
2009年 | 122篇 |
2008年 | 201篇 |
2007年 | 198篇 |
2006年 | 199篇 |
2005年 | 171篇 |
2004年 | 167篇 |
2003年 | 154篇 |
2002年 | 147篇 |
2001年 | 24篇 |
2000年 | 17篇 |
1999年 | 30篇 |
1998年 | 24篇 |
1997年 | 24篇 |
1996年 | 13篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 11篇 |
1992年 | 11篇 |
1991年 | 7篇 |
1990年 | 12篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 10篇 |
1986年 | 10篇 |
1985年 | 12篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1980年 | 5篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1972年 | 3篇 |
1961年 | 3篇 |
1937年 | 4篇 |
排序方式: 共有3466条查询结果,搜索用时 31 毫秒
991.
The prophylactic use of Rh immune globulin has been a medical success, protecting women who could be at risk from exposure to the Rh(D) antigen. Thus, it is not surprising that Rh(D) immunoprophylaxis has been extended from women with term pregnancies to all women with miscarriages, abortions, and ectopic pregnancies. In this article we review the existing medical literature to assess the risks of fetomaternal hemorrhage and Rh isoimmunization after complications of a first-trimester pregnancy, induced abortion, or ectopic pregnancy. The evidence to support the use of Rh immune globulin in the first trimester is sparse, but there is theoretic evidence of its necessity. Despite weak evidence to support its use, there is little risk. 相似文献
992.
Diejomaoh MF Omu AE Taher S Al-Busiri N Fatinikun T Fernandes S Al-Othman S 《Gynecologic and obstetric investigation》2003,56(4):197-202
BACKGROUND: Nitric oxide has potent relaxant effects on the pregnant uterus and has been associated with a quiescent uterus in animal and human studies. Nitric oxide donors have been used to arrest preterm labor and a reduction in nitric oxide production has been reported before the onset of labor. OBJECTIVE: The aim of the study was to estimate the serum levels of nitrate and nitrite in women undergoing spontaneous preterm labor and induced labor. MATERIALS AND METHOD: Venous blood was drawn from 39 patients before the onset of labor (control) and also from 17 patients undergoing induction of labor who were in active labor (study group A), and 24 patients in spontaneous preterm labor (study group B). Serum concentrations of nitrate and nitrite were estimated in the samples using the HPLC method. RESULTS: The maternal age of the patients was similar in all the groups. There was no significant difference in the mean gestational age at delivery between the control and group-A patients (38.86 vs. 38.29 weeks); however, there was a significant difference between the control and group-B patients (38.86 vs. 30.92; p < 0.0001), and between study groups A and B (38.29 vs. 30.92 weeks; p < 0.0001). The mean serum levels of nitrite in groups A and B (0.563 +/- 0.15 and 0.512 +/- 0.13, respectively) were significantly lower than the level in the control group (0.915 +/- 0.13; p < 0.0001). Although the serum nitrate levels in study groups A and B were lower than in the control group, this difference was not significant. The maternal outcome was satisfactory but, as expected, the mean birth weight of the babies in group B (1,665.73 +/- 863.84 g) was significantly lower than the birth weights in the control and group-A patients (p < 0.0001). CONCLUSION: There is a drop in nitric oxide production in active preterm labor and induced labor. These findings need to be confirmed in larger studies to establish the role of nitric oxide in the initiation of labor. 相似文献
993.
994.
995.
Bowel dysfunction after laparoscopic antireflux surgery: incidence,severity, and clinical course 总被引:5,自引:0,他引:5
PURPOSE: To evaluate the incidence, severity, and clinical course of postoperative bowel dysfunction, primarily diarrhea, after laparoscopic antireflux surgery. METHODS: Patients who underwent laparoscopic antireflux surgery during January to December 1998 responded to a questionnaire about pre-existing and postoperative bowel symptoms, which included questions about the type of bowel dysfunction (diarrhea, abdominal pain, bloating, constipation), onset in relation to surgery, frequency, severity, duration, use of medical resources or diagnostic evaluations, and treatment outcome. RESULTS: Of the 109 patients who underwent laparoscopic antireflux surgery at our center during the study, 84 (77%) completed the survey. Thirty-six (43%) had no bowel dysfunction before or after surgery, whereas 29 (35%) had pre-existing bowel dysfunction. New bowel symptoms developed postoperatively in 30 patients (36%), including bloating in 16 (19%) and diarrhea in 15 (18%). Two thirds of the patients with new diarrhea developed it within 6 weeks after surgery. The severity of the diarrhea ranged from mild to debilitating; 4 had fecal incontinence. Most patients (13/15) with diarrhea had symptoms for > or =2 years following surgery. No patient was hospitalized, and only 2 patients reported temporary work loss. CONCLUSION: Postoperative bowel dysfunction, namely diarrhea, is an important adverse effect of antireflux surgery. Awareness of this complication should lead to prompt recognition, effective management, and reduction in anxiety. 相似文献
996.
997.
A new series of 2-substituted mercapto-3H-quinozolines bearing 6-iodo and 2-heteroarylthio functions was synthesized and screened for their in vitro antitumor activity. Eighteen compounds were identified as active anticancer agents. N'-[(3-Benzyl-4-oxo-6-iodo-3H-quinazoline-2-yl)thioacetyl]-N(3)-ethylthiosemicarbazide (10), N-benzoyl-N'-[2-(3-benzyl-4-oxo-6-iodo-3H-quinozolin-2-yl)thioacetyl]hydrazine (12), and 2-[(3, 6-dioxo-pyridazin-4-yl)thio]-3-benzyl-4-oxo-6-iodo-3H-quinazoline (20) proved to be the most active members in this study. They showed MG-MID, GI(50) values of 12.8, 11.3, and 13.8 microM, respectively. The detailed synthesis and biological screening data are reported. 相似文献
998.
Opinion statement Mucosa-associated lymphoid tissue (MALT) lymphomas occur in a variety of organs, including the orbit, conjunctiva, salivary
glands, skin, thyroid gland, lungs, stomach, and intestine. These tumors are often localized and of indolent clinical behavior.
Diagnosis is made by pathologic evaluation of a tissue biopsy. Careful staging is mandatory and tailored to the initial presentation.
Staging includes a history and physical, chemistries, computed tomography scan, and bone marrow biopsy. This information is
supplemented with an ear, nose, and throat consultation, esophagogastro-duodenoscopy, colonoscopy, endoscopic ultrasound of
the stomach, and cytogenetic/immunohistochemical analysis of the tumors. Treatment is tailored to organ involvement and stage
at presentation. Eradication of Helicobacter pylori using a triple anti-H. pylori regimen approved by the US Food and Drug Administration is standard therapy for all H.
pyloripositive gastric MALT lymphomas. Endoscopic ultrasound- and computed tomographystaged gastric MALT stage IE tumors will achieve
a complete response with this approach in approximately 60% to 90% of patients (the more superficial the tumor [T1/T2], the
better the response). Patients with tumors that are T4 node-positive Musshoff stage IIE1 and IIE2 or tumors with adverse cytogenetics
should receive radiotherapy or surgery with or without radiotherapy. Tumors with a significant high-grade component or large
cell tumors with a minor low-grade MALT component should receive CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-based
chemotherapy. Localized MALT lymphomas of the orbit, conjunctiva, salivary glands, and thyroid gland are treated successfully
with radiotherapy. Surgery as first-line therapy for gastric MALT lymphomas was replaced by attempts at organ preservation.
In the past, margin-free surgical excision or tumor debulking followed by radiation therapy and chemotherapy has been highly
effective for gastric MALT lymphomas. Therefore, surgical excision of large cell or bulky tumors of the stomach, thyroid,
lung, and salivary gland, followed by adjuvant radiotherapy or chemotherapy, may still be an important consideration in selected
patients. Surgery still has a role for patients with relapsed or refractory lowgrade disease and life-threatening hemorrhage.
Disseminated MALT lymphomas are incurable and are treated primarily with chemotherapy according to symptoms. 相似文献
999.
The development of therapeutic monoclonal antibodies had been a significant advance in the treatment of B-cell non-Hodgkin's lymphoma (NHL). In the setting of blood and marrow transplantation (BMT), initial research was focused on in vitro graft purging. More recently, investigators have designed in vivo purging protocols using rituximab with the goal of obtaining tumor-free grafts. Exciting developments stem from the use of iodine 131 ((131)I)-tositumomab as well as yttrium 90 ((90)Y)-ibritumomab in myeloablative doses in blood and marrow transplantation protocols for high-risk patients. Finally, vigilance towards complications in particular unusual infections is advised given the profound immunosupressive state caused by these antibodies. 相似文献
1000.