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排序方式: 共有825条查询结果,搜索用时 46 毫秒
101.
Kumar M Liu ZR Thapa L Chang Q Wang DY Qin RY 《World journal of gastroenterology : WJG》2004,10(3):393-399
AIM: To investigate the anti-angiogenic effect of somatostatin receptor subtype 2 (SSTR2) gene transfer into pancreatic cancer cell line PC-3, and the mechanisms involved in this effect. METHODS: The full length human SSTR2 cDNA was introduced into pancreatic cancer cell line PC-3 by lipofectamine-mediated transfection. Positive clones were screened by G418 and stable expression of SSTR2 was detected by immunohistochemistry SABC methods and RT-PCR. Enzyme-linked immunosorbent assay (ELISA) was used to detect vascular endothelial growth factor (VEGF) levels in the cell culture supernatants of SSTR2-expressing cells, vector control and mock control cells. Furthermore, the expressions of VEGF and matrix metalloproteinase-2 (MMP-2) were detected by immunohistochemistry SABC methods and RT-PCR in these cells. RESULTS: VEGF levels in the cell culture supernatants were significantly reduced in the SSTR2-expressing cells (first week, 172.63+/-21.2 ng/L and after two months, 198.85+/-26.44 ng/L) compared with the vector control (first week, 790.39+/-86.52 ng/L and after two months, 795.69+/-72.35 ng/L) and mock control (first week, 786.42+/-90.62 ng/L and after two months, 805.32+/-84.36 ng/L) (P<0.05). The immunohistochemical assay showed a significant reduction of the integral optical density of VEGF and MMP-2 in the SSTR2-expressing cells (42.25+/-8.6 and 70.5+/-6.25, respectively) compared with the vector control (85.75+/-12.9 and 110.52+/-13.5, respectively) and mock control (82.6+/-9.28 and 113.56+/-9.62, respectively) (P<0.05). Conversely, the average gray value of VEGF and MMP-2 was significantly increased in the SSTR2-expressing cells (121.56+/-8.43 and 134.46+/-19.95, respectively) compared with the vector control (55.72+/-5.6 and 62.26+/-12.68, respectively) and mock control cells (58.48+/-6.2 and 65.49+/-9.16, respectively) (P<0.05). Moreover, the expressions of VEGF mRNA and MMP-2 mRNA were significantly reduced in the SSTR2-expressing cells (0.1384+/-0.017 and 0.2343+/-0.070, respectively) compared with the vector control (1.024+/-0.117 and 0.806+/-0.119, respectively) and mock control (1.085+/-0.105 and 0.714+/-0.079, respectively) (P<0.05). CONCLUSION: The expression of reintroduced human SSTR2 gene exerts its antiangiogenic effects by down-regulating the expressions of the factors involved in tumor angiogenesis and metastasis, suggesting SSTR2 gene transfer as a new strategy of gene therapy for pancreatic cancer. 相似文献
102.
Congenital hepatic fibrosis in Indian children 总被引:6,自引:0,他引:6
Poddar U Thapa BR Vashishta RK Girish CS Singh K 《Journal of gastroenterology and hepatology》1999,14(12):1192-1196
BACKGROUND: Congenital hepatic fibrosis (CHF) is an uncommon cause of portal hypertension in children. So far, there is no report of this from the subcontinent. We have studied the clinical spectrum of CHF in North Indian children. METHODS: Fifteen children were diagnosed with CHF on the basis of their liver histology over a period of 6.5 years. Their clinical details were recorded. Oesophagogastroduodenoscopy and abdominal ultrasonography were performed in all cases. All siblings were examined clinically; and ultrasonography, endoscopy and liver biopsy were performed if there was firm hepatomegaly. Children with variceal bleeding were managed by endoscopic sclerotherapy. The median age of these children was 8 years with a male to female ratio of 1.5:1. RESULTS: Only one sibling (of 33) was diagnosed as having CHF. The predominant presentations were variceal bleeding in six, abdominal distension in seven and incidental detection of organomegaly in two. Hepatomegaly was present in all patients and splenomegaly in all but one. Liver function and renal function tests were normal in all children, except for a raised serum alkaline phosphatase in six. Two children had associated renal cysts, two had choledochal cysts, one each had Caroli's disease and biliary atresia and two children had portal vein thrombosis. Variceal obliteration was achieved in five children after an average 4.8 sclerotherapy sessions and one required a mesocaval shunt. On follow up (median 41 months, range 1-80 months) all are doing well. CONCLUSIONS: Congenital hepatic fibrosis is mainly sporadic in India and associated renal lesions are uncommon. Endoscopic sclerotherapy is effective in controlling variceal bleed and the prognosis is universally good in the absence of renal diseases. 相似文献
103.
104.
Gastrointestinal perforations remain the most common cause of surgical pneumoperitoneum since time immemorial. The aim of
this study was to find out the effectiveness of plain radiography in diagnosing hollow viscous perforation. A prospective
analysis of a total of 1,723 patients of perforation peritonitis between January 2009 and June 2011, confirmed by exploratory
laparotomy, was worked out in the study. All these patients had undergone either an upright chest or erect abdominal or both
radiographs before undergoing operative procedure. Pneumoperitoneum was evaluated, and the findings were compared with that
of exploratory laparotomy. Out of the 1,723 patients of documented perforation on intraoperative finding, 1,537 patients showed
pneumoperitoneum on preoperative plain radiography. The overall positivity rate of plain radiography in detecting pneumoperitoneum
was 89.20%. The positivity rate was highest for stomach and duodenal perforation (94.19%) and the least for appendicular perforation
(7.69%) with highly significant difference (p value, <0.001). In developing world, where there is limited availability of resources and overburden of patients, imposing
a limitation in adapting advanced radiological technique as a first line of investigation, plain radiography may be considered
as a valuable screening tool in detecting pneumoperitoneum with high positivity rate. 相似文献
105.
106.
Hiroshi Ohara Bharat M. Pokhrel Rajan K. Dahal Shyam K. Mishra Hari P. Kattel Dharma L. Shrestha Yumiko Haneishi Jeevan B. Sherchand 《Tropical Medicine and Health》2013,41(3):113-119
The purpose of this study was to investigate the actual conditions of nosocomial infection control in Kathmandu City, Nepal as a basis for the possible contribution to its improvement. The survey was conducted at 17 hospitals and the methods included a questionnaire, site visits and interviews. Nine hospitals had manuals on nosocomial infection control, and seven had an infection control committee (ICC). The number of hospitals that met the required amount of personal protective equipment preparation was as follows: gowns (13), gloves (13), surgical masks (12). Six hospitals had carried out in-service training over the past one year, but seven hospitals responded that no staff had been trained. Eight hospitals were conducting surveillance based on the results of bacteriological testing. The major problems included inadequate management of ICC, insufficient training opportunities for hospital staff, and lack of essential equipment. Moreover, increasing bacterial resistance to antibiotics was recognized as a growing issue. In comparison with the results conducted in 2003 targeting five governmental hospitals, a steady improvement was observed, but further improvements are needed in terms of the provision of high quality medical care. Particularly, dissemination of appropriate manuals, enhancement of basic techniques, and strengthening of the infection control system should be given priority. 相似文献
107.
Kendall A. Bryant Trevor C. Van Schooneveld Ishwor Thapa Dhundy Bastola Laurina O. Williams Thomas J. Safranek Steven H. Hinrichs Mark E. Rupp Paul D. Fey 《Antimicrobial agents and chemotherapy》2013,57(1):37-41
We describe the transfer of blaKPC-4 from Enterobacter cloacae to Serratia marcescens in a single patient. DNA sequencing revealed that KPC-4 was encoded on an IncL/M plasmid, pNE1280, closely related to pCTX-M360. Further analysis found that KPC-4 was encoded within a novel Tn4401 element (Tn4401f) containing a truncated tnpA and lacking tnpR, ISKpn7 left, and Tn4401 IRL-1, which are conserved in other Tn4401 transposons. This study highlights the continued evolution of Tn4401 transposons and movement to multiple plasmid backbones that results in acquisition by multiple species of Gram-negative bacilli. 相似文献
108.
S Thapa 《Studies in family planning》1989,20(1):38-52
Knowledge and practice of family planning in Nepal increased considerably from mid-1976 through mid-1986, with significant improvements in the availability of and accessibility to contraceptives. However, a proportionately larger share of the achievements were made during 1976-81 than in 1981-86. The impact on fertility of contraceptive use during the decade was minimal. Knowledge and use of reversible contraceptive methods remained very low, primarily because of the continued strong emphasis on sterilization in Nepal's family planning program. Consequently, the welfare of many couples who may be in need of contraception for spacing births, but not necessarily for terminating childbearing, does not appear to be adequately addressed by the program. A more balanced emphasis on reversible methods of contraception does not necessarily imply that a substantially higher level of contraceptive prevalence would be required to reach the fertility target. Several steps to improve program performance and contraceptive method mix are suggested. 相似文献
109.
Lipoblastoma is an uncommon benign mesenchymal tumour that occurs primarily in children younger than 3 yrs of age. Despite the lesions being benign, great difficulty can be encountered in its management because of its tendency to invade the different fascial planes. A rare case of huge lipoblastoma diagnosed in a 22 months old child, involving various spaces of face and skull base has been reported. This huge tumour was completely and successfully removed through cheek incision without any postoperative complications. 相似文献
110.
Regulatory interest is increasing for drug transporters generally and P-glycoprotein (Pgp) in particular, primarily in the area of drug–drug interactions. To aid in both identifying and discharging the potential liabilities associated with drug–transporter interactions, the pharmaceutical industry has a growing requirement for routine and robust non-clinical assays. An assay was designed, optimised and validated to determine the in vitro inhibitory potency of new chemical entities (NCEs) towards human Pgp-mediated transport. [3H]-Digoxin was established as a suitable probe substrate by investigating its characteristics in the in vitro system (MDCKII-MDR1 cells grown in 24-multiwell inserts). The inhibitory potencies (apparent IC50) of known Pgp inhibitors astemizole, GF120918, ketoconazole, itraconazole, quinidine, verapamil and quinine were determined over at least a 1000-fold concentration range. Validation was carried out using manual and automatic techniques. [3H]-Digoxin was found to be stable and have good mass balance in the system. In contrast to [A → B] transport, [3H]-digoxin [B → A] transport rates were readily measured with good reproducibility. There was no evidence of saturation of transport up to 10 μM digoxin and 30 nM digoxin was selected for routine assay use, reflecting clinical therapeutic concentrations. IC50 values ranged over approximately 100-fold with excellent reproducibility. Results from manual and automated versions were in close agreement. This method is suitable for routine use to assess the in vitro inhibitory potency of NCEs on Pgp-mediated digoxin transport. Comparison of IC50 values against clinical interaction profiles for the probe inhibitors indicated the in vitro assay is predictive of clinical digoxin–drug interactions mediated via Pgp. 相似文献