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41.
Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations.  相似文献   
42.
ABSTRACT: Pemphigus vulgaris (PV) is an autoimmune disease of the skin and mucous membranes characterized by an autoantibody response against an epidermal cadherin. We performed high resolution HLA class II typing in 19 patients with PV from Rawalpindi, Pakistan and 19 non-Jewish European PV patients from Boston by sequence-specific oligonucleotide probe hybridization. The results were compared with two separate ethnically matched control populations. We found that PV patients from Pakistan had significantly increased frequencies of DRB1*1404 ( p = 0.01), DQA1*0101 ( p = 0.02), and DQB1*0503 ( p = 0.01). Among the patients of non-Jewish European ancestry, DRB1*1401 ( p < 10−6), DQA1*0101 ( p < 10−5) and DQB1*0503 ( p < 10−6), were increased in PV patients. Formal linkage analysis between the major histocompatibility complex and the PV antibody was performed in 67 relatives of the 19 Pakistani patients. The results showed strong evidence for linkage of HLA-DRB1*1404, DQA1*0101, DQB1*0503, with the presence of PV antibody in relatives’ families with a significant logarithm of the odds score of 6.06. Based on the three dimensional structure of class II molecules, we propose that HLA-DQA1*0101 and DQB1*0503, encode a negatively charged P9 peptide binding pocket of the DQ molecule and are significantly associated with susceptibility to PV in non-Jewish populations.  相似文献   
43.
Zito F A, Verderio P, Simone G, Angione V, Apicella P, Bianchi S, Conde A F, Hameed O, Ibarra J, Leong A, Pennelli N, Pezzica E, Vezzosi V, Ventrella V, Pizzamiglio S, Paradiso A & Ellis I
(2010) Histopathology 56, 720–726
Reproducibility in the diagnosis of needle core biopsies of non‐palpable breast lesions: an international study using virtual slides published on the world‐wide web Aims: To conduct an internet‐based study using virtual slides (VS) of sterotactic core biopsy specimens of non‐palpable breast lesions in order to evaluate interobserver reproducibility between pathologists. Methods and results: A total of 18 breast lesions, determined to be histologically complex by two pathologists, were selected. Digitized VSs were then created using QuickTime Virtual Reality technology (Apple, Cupertino, CA, USA) and posted on the world‐wide web. In all, 10 pathologists completed the evaluations of 18 VSs using the five diagnostic categories (B1–B5) from the European guidelines for quality assurance in breast cancer screening and diagnosis. Their results were compared with those of every other participating pathologist, and were then individually compared with the results of a highly experienced breast pathologist (referee). Of the 18 cases, 10 (56%) were classified by the referee as borderline (B3 and B4). Comparisons with reference values showed a less than satisfactory level of reproducibility (median κw = 0.60). As regards interobserver reproducibility, results showed that, in general, the level of agreement was not satisfactory (median κw = 0.53). Conclusions: Overall, the findings are comparable to those quality control studies using circulating slides when analysis is done on borderline cases.  相似文献   
44.
Fan  Zhen  Sun  Bing  Lang  Li-qin  Hu  Jie  Hameed  N. U. Farrukh  Wei  Zi-xuan  Zhuang  Qi-yuan  Cai  Jia-jun  Liu  Feng-tao  Mao  Yi-ting  Feng  Rui  Pan  Li 《Neurological sciences》2021,42(6):2353-2361
Neurological Sciences - Exploring the role of amygdala enlargement (AE) in temporal lobe epilepsy (TLE) without ipsilateral mesial temporal sclerosis (MTS) using comprehensive presurgical workup...  相似文献   
45.
AIM:To present a comprehensive analysis of incidence,clinicopathological features,appropriateness of surgical procedures,and survival for adenocarcinoma of the appendix.METHODS:A retrospective case analysis was conducted for the 10-year period 1998-2008.All patients diagnosed with adenocarcinoma of the appendix were analyzed for their demographics details,clinical features,tumor incidence and characteristics,tumor stage,surgical procedures performed,and their survival.RESULTS:Nine thousand three hundred and twentythree patients underwent appendectomies during the study period,and of these,10 (0.1%:8 men and 2 women with a mean age of 53.1 years,age range 21-83 years) were found to have primary adenocarcinoma of the appendix.Appendicular neoplasia was not suspected pre-operatively in any of the patients.Six (60%) patients underwent secondary right hemicolectomy.Four (40%) cases had appendectomy alone,and two of them died,whereas all those who underwent right hemicolectomy are alive and disease free.Five (50%) were reported to have grade 1 disease,three (30%) grade 2,and two (20%) grade 3 with mean survival of 34,48,and 22 mo,respectively.Six (60%) patients presented with advanced disease (Duke’s C and D).At the end of follow up (mean period:37.9 mo),eight patients are alive and disease free at the end of follow up.Overall mean survival was 36.3 mo (conf idence interval;16%-56%) with 41.3 and 16 mo for men and women,respectively.Mean survival for those with and without lymph node involvement was 33.6 and 40.2 mo,respectively.Right hemicolectomy gave better results than appendectomy alone,although the difference was not statistically signif icant due to the small number of cases.CONCLUSION:Adenocarcinoma of the appendix is extremely rare neoplasm with varied presentations,and is usually advanced when diagnosed.Right hemicolectomy is the treatment of choice for such tumors.  相似文献   
46.
To study the various modes of presentation, diagnosis, and management of surgical emergencies of tubercular abdomen. This prospective study of surgical emergencies of tubercular abdomen was conducted in 50 patients who attended our surgical emergency from 2006 to 2008. Patients were evaluated thoroughly with history, physical examination, routine investigations, and special investigations such as ELISA, PCR, barium studies of gastrointestinal tract, and diagnostic laparoscopy as required and managed with medical and surgical treatment as necessary. The most of patients were from rural areas, in the third to sixth decades with slight male preponderance. Abdominal pain, vomiting, and constipation were commonest presenting symptoms. About 20 % patients had history of pulmonary tuberculosis and 16 % patients presented with ascites. PCR for blood and ascitic fluid was positive in 72 and 87.5 % patients, respectively. About 24 % patients were managed nonoperatively and responded to ATT. About 76 % patients needed surgery among which one-fifth of patients were operated in emergency. Procedures like adhesiolysis of gut (47.3 %), strictureplasty (10.5 %), resection anastomosis (5.2 %), right hemicolectomy (5.2 %), and ileotransverse anastomosis (7.8 %) were performed in 30 patients and peritoneal biopsy and lymph node biopsy in the remaining 8 patients. Both medically and surgically managed patients were put on antitubercular therapy. Abdominal tuberculosis is a disease of middle-aged rural people, presenting commonly with abdominal pain and vomiting with right lower abdominal tenderness. PCR (blood and ascites) for tuberculosis is much more sensitive than IgM ELISA (blood and ascites). The most of patients required surgical procedures and all patients responded dramatically to antitubercular therapy symptomatically with increase in the hemoglobin level and decrease in ESR.  相似文献   
47.
Surgical resection has had control rates of 53% to 77% in the treatment of extra-abdominal desmoid tumors. Surgical excision combined with external beam radiation therapy (EBRT) has had local control rates of up to 83% in some series. The purpose of this study was to evaluate the effectiveness of resection combined with radiotherapy (brachytherapy, EBRT, or both) in the treatment of extra-abdominal desmoid tumors. We retrospectively reviewed the charts of 24 consecutive patients (27 histologically confirmed extra-abdominal desmoid tumors). Patients were included in the study if they had a lesion that was potentially resectable with a wide margin, allowing for limb salvage, and if they did not have a contraindication to radiotherapy. Limb functioning was assessed with the Musculoskeletal Tumor Society (MSTS) scoring system. Seventeen patients (7 men, 10 women) with 19 tumors met the inclusion criteria. Mean age at diagnosis was 23.4 years. Follow-up (mean, 4.28 years) involved serial clinical examinations and magnetic resonance imaging of tumor sites. After surgery, the tumors were treated with brachytherapy (n = 6), EBRT (n = 10), or both (n = 3). Two of the 17 tumors in patients with negative margins of resection recurred locally (local control rate, 88.2%). Mean MSTS score was 29/30 (96.7%). The role of surgery, radiotherapy, chemotherapy, hormone therapy, and other treatments for extra-abdominal desmoid tumors is not well defined. When wide-margin resection and radiotherapy can be performed with limb preservation surgery, local control and complication rates compare favorably with those of other reported methods of treatment. Given the results and limitations of our study, we cannot make a definitive recommendation as to which modality--brachytherapy or EBRT--should be used in the treatment of extra-abdominal desmoid tumors.  相似文献   
48.
Femoral neck stress fractures (FNSFs) are rare,constituting only 5% of all stress fractures in young adults.These fractures are usually seen in athletes,military recruits and patients with underlying m...  相似文献   
49.
Thirty-seven consecutive patients with singleton pregnancies in "uncomplicated" preterm labor with intact membranes suitable for tocolysis were evaluated for evidence of silent chorioamnionitis by means of maternal serum C-reactive protein and amniotic fluid white blood cell count, Gram stain, and cultures. Abnormalities in these markers of infection were found to be significantly more common in cases that were refractory to tocolysis. These cases also showed both pathologic evidence of chorioamnionitis and a significantly greater neonatal early infectious morbidity. We conclude that silent chorioamnionitis is a significant cause of "uncomplicated" preterm labor refractory to conventional methods of tocolysis.  相似文献   
50.
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