全文获取类型
收费全文 | 2717篇 |
免费 | 173篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 86篇 |
妇产科学 | 64篇 |
基础医学 | 252篇 |
口腔科学 | 54篇 |
临床医学 | 242篇 |
内科学 | 561篇 |
皮肤病学 | 43篇 |
神经病学 | 126篇 |
特种医学 | 98篇 |
外科学 | 467篇 |
综合类 | 46篇 |
一般理论 | 7篇 |
预防医学 | 294篇 |
眼科学 | 103篇 |
药学 | 286篇 |
中国医学 | 25篇 |
肿瘤学 | 123篇 |
出版年
2023年 | 29篇 |
2022年 | 40篇 |
2021年 | 85篇 |
2020年 | 83篇 |
2019年 | 122篇 |
2018年 | 139篇 |
2017年 | 103篇 |
2016年 | 112篇 |
2015年 | 110篇 |
2014年 | 143篇 |
2013年 | 205篇 |
2012年 | 252篇 |
2011年 | 266篇 |
2010年 | 140篇 |
2009年 | 128篇 |
2008年 | 177篇 |
2007年 | 155篇 |
2006年 | 143篇 |
2005年 | 115篇 |
2004年 | 90篇 |
2003年 | 81篇 |
2002年 | 55篇 |
2001年 | 21篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 9篇 |
1997年 | 12篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1992年 | 7篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1975年 | 5篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1968年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有2908条查询结果,搜索用时 17 毫秒
991.
Rachdi R Kasdaoui B Messaoudi F Basly M Yazidi M Chlayah M Messaoudi L Chibani M 《La Tunisie médicale》2005,83(12):764-769
In more of positive diagnosis, echography makes it possible to approach the histological nature of ovarian tumors. From a series of 106 cases of ovarian tumours, we propose to evaluate this approach by analysing the various echographic signs according to histological types'. The serous cysts are anechogen in 77,7% of the cases. The mucinous cysts are anechogen in 71,4% and finely echogen in 28,5% of the cases. The dermoid cysts are echogen in 47,3% and heterogeneous in 26,3%. The endometriosic cysts can be finely echogen (45%), heterogeneous (25%) or echogen (20%). The malignant tumors are of mixed aspect in 54,55% of the cases. The sensitivity of echography for the malignant tumors is 81,82% whereas specificity is 75,79%. The negative predictive value is 97,3%, and the positive predictive value is 28,13%. The size of the tumor, the vegetations and the partitions are also studied: a size lower than 5 cm and the absence of partition and vegetation are synonymous with benignity in all the cases. 相似文献
992.
Bazargan M Bazargan-Hejazi S Baker RS 《Journal of health care for the poor and underserved》2005,16(2):328-344
This study applied the Behavioral Model for Vulnerable Populations framework to examine the correlates of depression and the receipt of medical treatment among low-income Hispanics and African Americans residing in public housing. We compared three groups: those who reported (1) self-diagnosed but without physician-diagnosed depression, (2) depression diagnosed by a physician but who did not receive pharmaceutical treatment, and (3) depression diagnosed by a physician and antidepressant pharmacotherapy consumed by patient. Random samples of 287 adults from three public housing communities were surveyed. Over 48% of this sample reported that they were suffering from depression. One out of three people who reported being depressed also said that a physician had never diagnosed his or her condition. Only 40% of those who said that a physician had diagnosed depression also reported taking antidepressant medication. Untreated depression among underserved racial and ethnic minorities is alarming and points to an urgent need for intervention. 相似文献
993.
PURPOSE: Open surgical repair has been the standard treatment for intraperitoneal bladder rupture. We sought to explore the possibility of nonoperative treatment of isolated intraperitoneal bladder rupture in children. MATERIALS AND METHODS: Eight children (4 girls and 4 boys) with a mean age of 6.3 +/- 4.6 years (range 1 to 13) presented with isolated posttraumatic intraperitoneal bladder rupture between 1993 and 2003. Retrograde cystogram was performed in all cases. Diagnosis was confirmed by aspiration and chemical analysis of the free intraperitoneal fluid in patients with an equivocal cystogram. Four patients who presented early in the series (group 1) were treated with the classic open repair, whereas the last 4 patients (group 2) were treated nonoperatively with adequate bladder drainage and percutaneous intraperitoneal tube drain. The mechanisms of injury, clinical presentation, management, complication, hospital stay and duration of catheterization were reviewed in both groups. RESULTS: Six patients had a history of a direct blow to the full bladder, while 2 presented following a motor vehicle accident. All patients presented with vomiting and abdominal distention, and 5 had mild gross hematuria without associated clots or hemodynamic instability. One patient in group 1 had early urinary leakage and wound sepsis, and was treated conservatively. All patients in group 2 demonstrated significant improvement in general condition within a few hours of the bladder and peritoneal drainage. Intraperitoneal tube drains were removed at 1 to 4 days. There were no post-intervention complications in group 2 and surgical treatment was never required. Mean indwelling catheter duration was 9.3 +/- 7.9 and 11.8 +/- 2.6 days (p = 0.24), and mean hospital stay was 10.5 +/- 8.4 and 7.3 +/- 3.9 days (p = 0.56) in groups 1 and 2, respectively. CONCLUSIONS: Nonoperative treatment is a justified initial approach for isolated intraperitoneal bladder rupture in children. Indications for surgical intervention include improper bladder drainage, unduly prolonged urinary drainage through the peritoneal drain and/or lack of clinical improvement. 相似文献
994.
Neuroendocrine tumors (NETs) represent a large group of neoplasms deriving from pluripotent stem cells or from differentiated neuroendocrine cells that are characterized by the expression of different peptides and biogenic amines. These rare tumors tend to grow slowly and are notoriously difficult to localize, at least in the early stages. Diagnostics involve blood, urine and biochemical examination as well as imaging modalities. Imaging is achieved by a variety of techniques such as radiological morphological imaging methods, for example, sonography, computerized tomography (CT)/magnetic resonance imaging (MRI), angiography and finally, nuclear functional imaging methods such as metaiodobenzylguanidine (MIBG), somatostatin receptor scintigraphy (SRS), vasoactive intestinal peptide receptor scintigraphy (VIPRS) and positron emission tomography (PET) using (18)F labeled deoxyglucose (FDG) and fluorinated dihydroxyphenylalanine ((18)F-DOPA) as a radioisotopic marker. (131)I-labeled MIBG is a well-established radiopharmaceutical for localization and therapy of phechromocytoma and paraganglioma. The majority of neuroendocrine tumors possess a high density of somatostatin receptors. This observation provided the basis for the development of various radiolabeled somatostatin peptide analogs as imaging agents and therapeutics in nuclear medicine. FDG-PET is now performed in a wide variety of tumors and indications, including diagnosis, staging, re-staging and evaluation of the response to treatment. (18)F-DOPA-PET may be useful if (18)F-FDG-PET scan result is negative. (99m)Tc-pentavalent dimercaptosuccinic acid ((99m)Tc-DMSA-V) or (99m)Tc sestamibi ((99m)Tc-MIBI) or (99m)Tc-tetrofosmin is used only for diagnosis of certain NETs such as medullary thyroid cancer. The expiences with other nuclear medicinie imaging and therapy modalities such as cholecystokinin (CCK)-B/gastrin-receptors, bombesin/gastrin-releasing peptide receptor scintigraphy are still limited, and further clinical studies are needed. The studies using vascular endothelial growth factor (VEGF) for tumor angiogenesis imaging, annexin-V for imaging apoptosis and agents for hypoxia imaging are still in an early stage and the clinical role for these agents needs to be defined. In conclusion, no single imaging technique identifies all the metastatic sites of NETs. The best results may be obtained with a combination of functional imaging such as PET or/and SRS and morphologic imaging with CT and/or MR imaging. Many molecular imaging and therapy modalities fur NETs are recently under investigation or being developed, the usefulness of these modalities, however, has to be evaluated by well-designed and multicentre studies. 相似文献
995.
Arash Rashidi Behnoush Mohammadpour-Ahranjani Majid Karandish Mohammad-Reza Vafa Majid Hajifaraji Farzaneh Ansari Shima Sadeghi Mohsen Maddah Nasser Kalantari Mohammad-Bagher Akhavi-Rad 《Central European Journal of Medicine》2007,2(4):481-487
We examined the association between overweight/gender and skipping breakfast among adolescent students in Tehran city using
a cross-sectional study and a multistage random sampling method. All educational zones in Tehran city were covered during
the educational year of 2000–01. In total, 2321 students aged 11–16 years (1068 male; 1263 female) participated in the study.
Weight and height were measured and body mass index (BMI; kg/m2) was calculated. Overweight, pre-obesity and obesity were defined as BMI ≥ 85
th
, 85
th
to 95
th
, and ≥ 95
th
percentile of age-sex-specific BMI reference values, respectively. Self-reported frequency of breakfast consumption was categorized
as usual/always, often, and rarely/never (5–7, 2–4 and 0–1 times/wk, respectively). Student’s t and Chi-square tests were employed to analyze the data. Statistical inferences were made at α = 0.05. In boys and girls, the mean ± standard deviation of BMI was 19.8 ± 4.0 and 20.6 ± 4.1 kg/m2, the 18.8% and 23.1% were overweight, and 7.3% and 8.3% were obese, respectively. There was a significant difference in the
frequency of breakfast consumption between obese and normal male students (P < 0.001). Differences between pre-obese and normal, and obese and normal female students were also significant (P < 0.002 and P < 0.001, respectively). A significant difference was found in the frequency of breakfast consumption between male and female
adolescents in all three categories (P < 0.001). These results suggest that obese and female adolescents are more likely to skip breakfast than their normal and
male peers and are therefore at higher risk for growth deficits and low educational performance. Preventive/educational programs
are urgently needed in this age group. 相似文献
996.
997.
The objective of the present study was to describe the intake of dietary fatty acids among healthy 15-year-old boys and girls and to relate the intake of specific fatty acids and the fatty acid composition of the serum cholesterol esters to serum lipid, apolipoprotein (Apo) and insulin concentrations respectively. Fifty-two girls and forty-two boys were randomly selected from the official population register. Unexpectedly, significant inverse associations were found between the dietary content of saturated fatty acids with a chain length of four to fifteen C atoms, mainly derived from milk fat, as well as the corresponding fatty acids in the serum cholesterol esters, on the one hand and the serum concentrations of cholesterol and ApoB on the other. The estimated dietary intake of 4:0-10:0, 12:0 and 14:0 respectively, were all significantly inversely related to the serum cholesterol (r -0.32, r -0.31, r -0.30, all and ApoB (r -0.42, r -0.42, and r -0.40, all concentrations in girls and 12:0 to the ApoB concentration (r -0.55, in boys. The proportions of 12:0 and 15:0 in the serum cholesterol esters were negatively correlated with the serum cholesterol concentrations in both girls (r -0.34, r -0.32, and boys (r -0.53, r -0.32, and with the ApoB concentrations among boys (r -0.61, r -0.43, It is conceivable that milk fat contains or is associated with some component in the diet, or some other characteristics of the food intake, which counterbalances the expected positive relationships between saturated fat intake and lipid levels. 相似文献
998.
Mohsen G El-Awady M Abdelazeem O 《The Journal of the Egyptian Public Health Association》2001,76(5-6):469-486
The current study was carried out in Desok district-Kafr El Sheikh province, to measure the prevalence of primary and secondary infertility among rural women and to study some risk factors as well. The study included 1125 married women between 15-49 years. The results of the study showed that; 7.9% reported secondary infertility 2.5% experienced primary infertility, the prevalence of primary infertility is higher among women under 30 years than older ages, and secondary infertility increases with advance in age. Both types of infertility were higher among women married under the age of 16 or above 30 years. There was an insignificant difference between fertile group and infertile groups regarding age at menarche. Irregular menses was significantly higher among infertile groups compared to fertile group. Secondary infertility group had significant higher abortion and difficult labor than fertile group. There was an insignificant difference between the study groups regarding illiteracy rate. Chronic illnesses of women as well as husbands were significantly more reported among women with secondary infertility. In conclusion, the overall prevalence of infertility is 10.4 %. 相似文献
999.
The objective of this article is to report the development, implementation, and early results of a non-graded normative dental student clinical performance assessment system based on our competencies documents. The normative system (student performance is compared to evidence-based clinical standards) was used and evaluated during the 2002-03 academic year and is now gradually replacing the traditional summative (numerical) grading system previously used at Baylor College of Dentistry. The methodology included: 1) consensus development of new clinical performance assessment forms over the summer of 2002; 2) concurrent fourth-year clinical faculty calibration to the new forms; 3) implementation at the beginning of the senior year for the Class of 2003; and 4) faculty and student evaluation surveys in May 2003. Every step of each clinical procedure was recorded, weekly performance summaries by both students and faculty were collected, and periodic workshops were held to refine the forms and further calibrate faculty. The results showed strong positive responses to the new system by graduates and faculty alike. We conclude that early results warrant broadened efforts toward a continuously improved schoolwide normative student clinical performance assessment system. 相似文献
1000.
Isolated congenital anosmia with morphologically normal olfactory bulb in two Iranian families: a new clinical entity? 总被引:1,自引:0,他引:1
Ghadami M Majidzadeh-A K Morovvati S Damavandi E Nishimura G Komatsu K Kinoshita A Najafi MT Niikawa N Yoshiura K 《American journal of medical genetics. Part A》2004,131(3):307-309
Congenital total loss of the sense of smell occurs as a part of a syndrome or isolated anosmia. Kallmann syndrome is the most well known congenital anosmia associated with hypogonadotropic hypogonadism. Isolated congenital anosmia (ICA) is a very rare condition and appears to be due to changes in the olfactory epithelium or to aplasia of the olfactory nerve, bulb, and tract. Here we report two unrelated Iranian families with ICA. One family consisted of nine affected members, and the other family contained three affected members. Clinical history, physical examination, and smell testing by intravenous injection of combined vitamins (Alinamin trade mark, Takeda Pharmaceutical Co. Ltd., Japan) confirmed the disease in each affected member. No signs of hypogonadism or other neurological disorders were observed in any affected members. Family analysis with the complete ascertainment method under assumption of the same condition in the two families suggested that the disease is not inconsistent with an autosomal dominant mode with incomplete penetrance. The inheritance in one family appears unusual, i.e., there were no affected individuals in the third generation. When only two upper generations in the family are concerned, the segregation ratio was 0.39 +/- 0.11. Male-to-male transmissions were observed and both sexes were affected in both families. Magnetic resonance imaging (MRI) of the olfactory bulb and sulcus revealed no evidence of morphological changes in all affected members, suggesting that these patients have either a defect in the olfactory epithelium or a functional defect in the olfactory cortex. 相似文献