全文获取类型
收费全文 | 5693篇 |
免费 | 389篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 58篇 |
儿科学 | 183篇 |
妇产科学 | 123篇 |
基础医学 | 663篇 |
口腔科学 | 194篇 |
临床医学 | 484篇 |
内科学 | 1285篇 |
皮肤病学 | 151篇 |
神经病学 | 296篇 |
特种医学 | 142篇 |
外国民族医学 | 4篇 |
外科学 | 796篇 |
综合类 | 213篇 |
一般理论 | 2篇 |
预防医学 | 464篇 |
眼科学 | 111篇 |
药学 | 534篇 |
中国医学 | 69篇 |
肿瘤学 | 342篇 |
出版年
2023年 | 76篇 |
2022年 | 118篇 |
2021年 | 333篇 |
2020年 | 168篇 |
2019年 | 217篇 |
2018年 | 210篇 |
2017年 | 170篇 |
2016年 | 218篇 |
2015年 | 226篇 |
2014年 | 274篇 |
2013年 | 332篇 |
2012年 | 490篇 |
2011年 | 524篇 |
2010年 | 277篇 |
2009年 | 218篇 |
2008年 | 336篇 |
2007年 | 277篇 |
2006年 | 284篇 |
2005年 | 258篇 |
2004年 | 208篇 |
2003年 | 176篇 |
2002年 | 175篇 |
2001年 | 31篇 |
2000年 | 33篇 |
1999年 | 39篇 |
1998年 | 32篇 |
1997年 | 22篇 |
1996年 | 20篇 |
1995年 | 24篇 |
1994年 | 26篇 |
1993年 | 23篇 |
1992年 | 19篇 |
1991年 | 12篇 |
1990年 | 21篇 |
1989年 | 23篇 |
1988年 | 18篇 |
1987年 | 24篇 |
1986年 | 17篇 |
1985年 | 9篇 |
1984年 | 8篇 |
1983年 | 15篇 |
1982年 | 14篇 |
1981年 | 14篇 |
1980年 | 8篇 |
1979年 | 7篇 |
1977年 | 9篇 |
1975年 | 8篇 |
1974年 | 6篇 |
1972年 | 6篇 |
1971年 | 8篇 |
排序方式: 共有6114条查询结果,搜索用时 31 毫秒
11.
Abdul Rahman D El Kinge Rami A Mahfouz Ali I Shamseddine Ali T Taher 《Blood coagulation & fibrinolysis》2007,18(6):577-579
Recombinant activated factor VII has been Food and Drug Administration approved to treat hemorrhages in hemophiliac patients with inhibitors and in acquired hemophilia patients. Recombinant activated factor VII use has also been considered for the management of uncontrolled bleeding in a number of congenital and acquired hemostatic abnormalities. The myeloproliferative disorders are a group of clonal hematologic diseases where, frequently, abnormal platelet function is considered a hallmark. This is the first case report addressing the clinical benefit of off-label use of recombinant activated factor VII in an attempt to control intractable bleeding in a patient with a myeloproliferative disorder after splenectomy. 相似文献
12.
Abdul Rahman Arishi M. Ezzedien Rabie M. Shahid Hussain Khan Hassan Sumaili Hassan Shaabi Nabil Tadros Michael Bheem Sing Shekhawat 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2008,12(3):321-325
Spillage of gallstones may occur in the course of laparoscopic cholecystectomy. The incidence of this mishap and its consequences are variable. Ignored by many surgeons, stone spillage may be the source of significant morbidity many years after surgery. In this report, we describe the clinical course of a patient who presented with upper abdominal pain and swelling. The past history was positive for laparoscopic cholecystectomy 15 years earlier. After excision, the swelling was found to be a pseudocyst formed around spilled gallstones during a previous cholecystectomy. Apart from postoperative wound infection, the patient recovered well and remains so. Here, we discuss the problem and provide suggestions for spillage prevention and stone retrieval once spillage occurs. 相似文献
13.
Niyaz Ahmed Mahfooz Alam A Abdul Majeed S Asad Rahman Angel Cataldi Debby Cousins Seyed E Hasnain 《Infection, genetics and evolution》2003,2(3):193-199
Tuberculosis in seals is caused by a member of the Mycobacterium tuberculosis complex referred to as the 'seal bacillus'. Fluorescent amplified-fragment length polymorphism (FAFLP) analysis was applied to isolates from four Australian and six Argentinean seals and compared with FAFLP pattern for standard strains belonging to the M. tuberculosis complex. The FAFLP profiles derived from EcoRI/MseI restricted fragments of blind coded DNA samples differentiated the seal bacillus from other members of the M. tuberculosis complex. According to the phylogenetic analysis performed using FAFLP data, seal bacilli appear to have diverged significantly from other members of the M. tuberculosis complex. We describe the suitability of a panel of 19 highly polymorphic markers for rapid identification and comparative genomic analyses of the seal bacillus strains. It is likely that these bacilli got separated from the M. tuberculosis lineage as a result of different insertion deletion events occurring on a genome wide scale. Our analysis reveals that the seal bacillus and M. bovis are genetically related and therefore, might have originated from a common ancestor. Our data additionally support the hypothesis that seal bacillus occupies a unique taxonomic position within the M. tuberculosis complex. 相似文献
14.
Mazin A.I. Sarsam F.R.C.S. Colin S. Campbell F.R.C.S. Nizar A. Yonan F.R.C.S. Abdul K. Deiraniya F.R.C.S. Ali N. Rahman F.R.C.S. 《Journal of cardiac surgery》1993,8(3):344-349
A bstract Forty patients underwent orthotopic cardiac transplantation at Wythenshawe Hospital between May 1991 and November 1992. Twenty patients had transplantation using an alternative technique that preserves the shape of the left atrium and leaves the right atrium intact (group A). The remaining twenty had conventional transplantation using the technique described by Lower and Shumway (group B). The patients were randomized to either the new or the conventional technique on an alternate basis. There was no mortality in group A, but two patients in group B developed right ventricular failure and died. Two patients in each group developed nodal rhythm and all four recovered sinus rhythm. Echocardiography and Doppler velocimetry at the transvalvular level confirmed normal atrial function in group A with erratic atrial contraction wave in group B. There was also slightly lower incidence of mitral and tricuspid valve regurgitation in group A than in group B. The improved atrial function in group A may play a part in the prevention of right sided failure following cardiac transplantation. 相似文献
15.
Gao HZ Kobayashi K Tabata A Tsuge H Iijima M Yasuda T Kalkanoglu HS Dursun A Tokatli A Coskun T Trefz FK Skladal D Mandel H Seidel J Kodama S Shirane S Ichida T Makino S Yoshino M Kang JH Mizuguchi M Barshop BA Fuchinoue S Seneca S Zeesman S Knerr I Rodés M Wasant P Yoshida I De Meirleir L Abdul Jalil M Begum L Horiuchi M Katunuma N Nakagawa S Saheki T 《Human mutation》2003,22(1):24-34
Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease. 相似文献
16.
Detection of Vi-negative Salmonella enterica serovar typhi in the peripheral blood of patients with typhoid fever in the Faisalabad region of Pakistan 下载免费PDF全文
Baker S Sarwar Y Aziz H Haque A Ali A Dougan G Wain J Haque A 《Journal of clinical microbiology》2005,43(9):4418-4425
The synthesis and transportation proteins of the Vi capsular polysaccharide of Salmonella enterica serovar Typhi (serovar Typhi) are encoded by the viaB operon, which resides on a 134-kb pathogenicity island known as SPI-7. In recent years, Vi-negative strains of serovar Typhi have been reported in regions where typhoid fever is endemic. However, because Vi negativity can arise during in vitro passage, the clinical significance of Vi-negative serovar Typhi is not clear. To investigate the loss of Vi expression at the genetic level, 60 stored strains of serovar Typhi from the Faisalabad region of Pakistan were analyzed by PCR for the presence of SPI-7 and two genes essential for Vi production: tviA and tviB. Nine of the sixty strains analyzed (15%) tested negative for both tviA and tviB; only two of these strains lacked SPI-7. In order to investigate whether this phenomenon occurred in vivo, blood samples from patients with the clinical symptoms of typhoid fever were also investigated. Of 48 blood samples tested, 42 tested positive by fliC PCR for serovar Typhi; 4 of these were negative for tviA and tviB. Three of these samples tested positive for SPI-7. These results demonstrate that viaB-negative, SPI-7-positive serovar Typhi is naturally occurring and can be detected by PCR in the peripheral blood of typhoid patients in this region. The method described here can be used to monitor the incidence of Vi-negative serovar Typhi in regions where the Vi vaccine is used. 相似文献
17.
Diego A. Gomez Philip A. May Barbara G. Tabachnick Julie M. Hasken Elizabeth R. Lyden Wendy O. Kalberg H. Eugene Hoyme Melanie A. Manning Margaret P. Adam Luther K. Robinson Kenneth Lyons Jones David Buckley Omar A. Abdul‐Rahman 《American journal of medical genetics. Part A》2020,182(10):2243-2252
Fetal alcohol spectrum disorders (FASD) describe a range of physical, behavioral, and neurologic deficits in individuals exposed to alcohol prenatally. Reduced palpebral fissure length is one of the cardinal facial features of FASD. However, other ocular measurements have not been studied extensively in FASD. Using the Fetal Alcohol Syndrome Epidemiologic Research (FASER) database, we investigated how inner canthal distance (ICD), interpupillary distance (IPD), and outer canthal distance (OCD) centiles differed between FASD and non‐FASD individuals. We compared ocular measurement centiles in children with FASD to non‐FASD individuals and observed reductions in all three centiles for ICD, IPD, and OCD. However, when our non‐FASD children who had various forms of growth deficiency (microcephaly, short‐stature, or underweight) were compared to controls, we did not observe a similar reduction in ocular measurements. This suggests that reductions in ocular measurements are a direct effect of alcohol on ocular development independent of its effect on growth parameters, which is consistent with animal models showing a negative effect of alcohol on developing neural crest cells. Interpupillary distance centile appeared to be the most significantly reduced ocular measure we evaluated, suggesting it may be a useful measure to be considered in the diagnosis of FASD. 相似文献
18.
Diego A. Gomez Lynne M. Bird Nicole Fleischer Omar A. Abdul‐Rahman 《American journal of medical genetics. Part A》2020,182(9):2021-2026
Angelman syndrome (AS) is caused by several genetic mechanisms that impair the expression of maternally‐inherited UBE3A through deletions, paternal uniparental disomy (UPD), UBE3A pathogenic variants, or imprinting defects. Current methods of differentiating the etiology require molecular testing, which is sometimes difficult to obtain. Recently, computer‐based facial analysis systems have been used to assist in identifying genetic conditions based on facial phenotypes. We sought to understand if the facial‐recognition system DeepGestalt could find differences in phenotype between molecular subtypes of AS. Images and molecular data on 261 individuals with AS ranging from 10 months through 32 years were analyzed by DeepGestalt in a cross‐validation model with receiver operating characteristic (ROC) curves generated. The area under the curve (AUC) of the ROC for each molecular subtype was compared and ranked from least to greatest differentiable phenotype. We determined that DeepGestalt demonstrated a high degree of discrimination between the deletion subtype and UPD or imprinting defects, and a lower degree of discrimination with the UBE3A pathogenic variants subtype. Our findings suggest that DeepGestalt can recognize subclinical differences in phenotype based on etiology and may provide decision support for testing. 相似文献
19.
Peiwen Pan Mari Leppilampi Silvia Pastorekova Jaromir Pastorek Abdul Waheed William S. Sly Seppo Parkkila 《The Journal of physiology》2006,571(2):319-327
Using real-time PCR and immunohistochemistry, we have examined the expression of carbonic anhydrase isozymes (CA) I, II, III, IV, IX, XII, XIII and XIV in the brain, kidney, stomach and colon of the wild-type, CA II-deficient ( Car2−/− ), and CA IX deficient ( Car9−/− ) mice. The expression of Car4, Car12, Car13 and Car14 mRNAs did not show any significant deviations between the three groups of mice, whereas both groups of CA deficient mice showed decreased expression levels of Car1 in the colon and Car3 in the kidney. The Car2 mRNA level was greatly reduced but not completely abolished in all four tissues from the Car2−/− mice in which no CA II protein was expressed. Sequencing the Car2 cDNA isolated from C57BL6 Car2−/− mice revealed two nucleotide differences from the wild-type C57BL6 mice. One is a silent polymorphism found in Car2 mRNA from wild-type DBA mice, which is the strain that provided the original mutagenized chromosome. The second change is a mutation that causes prematurely terminated translation at codon 155 (Gln155X). Car9 mRNA and CA IX protein expression levels were up-regulated about 2.5- and 3.6-fold, respectively, in the stomach of the Car2−/− mice. These results suggest that the loss of function of cytosolic CA II in the stomach of Car2−/− mice leads to up-regulation of an extracellular CA, namely CA IX, which is expressed on the cell surface of the gastric epithelium. 相似文献
20.
Abdul A. Hassoni Peter T. A. Gray 《Pflügers Archiv : European journal of physiology》1994,428(3-4):269-274
The control of Cl– conductance in rat parotid isolated acinar cells was studied by combined use of whole-cell recording and flash photolysis techniques. Cells were voltage-clamped either at a membrane potential of –40 mV or stepped between –85 mV and 0 mV. Bath-applied carbachol and noradrenaline evoked Cl– current at –85 mV and K+ current at 0 mV. Similar current activations resulted from the photolytic release of either inositol trisphosphate (InsP
3) or Ca2+ by a brief near-UV flash. The peak amplitudes of the Cl– conductance (at –85 mV), measured relative to the K+ conductance (at 0 mV), evoked by application of carbachol, noradrenaline or direct manipulation of cytosolic free calcium ([Ca2+]i), were very similar, being 0.56±0.09 (mean±SEM,n=9), 0.52 ± 0.01 (n=7) and 0.46±0.06 (n=7). In contrast, the relative amplitude of the Cl– conductance evoked by InsP3 was much larger: 1.49±0.24 (n=9). Neither bath application of isoprenaline nor photolysis of caged cAMP induced any detectable membrane current. The most probable interpretation of these results is that the observed activation of Cl– conductance by agonists can be explained by the elevation of [Ca2+]i alone. In addition, the present results provide further support for the previously reported suggestion that the Cl– channels and the Ca2+-release sites are co-localised [10]. 相似文献