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991.
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993.
We studied transmission patterns of severe acute respiratory syndrome (SARS) among medical students exposed exclusively to the first SARS patient in the Prince of Wales Hospital in Hong Kong, before his illness was recognized. We conducted a retrospective cohort study of 66 medical students who visited the index patient's ward, including 16 students with SARS and 50 healthy students. The risk of contracting SARS was sevenfold greater among students who definitely visited the index case's cubicle than in those who did not (10/27 [41%] versus 1/20 [5%], relative risk 7.4; 95% confidence interval 1.0 to 53.3). Illness rates increased directly with proximity of exposure to the index case. However, four of eight students who were in the same cubicle, but were not within 1 m of the index case-patient, contracted SARS. Proximity to the index case-patient was associated with transmission, which is consistent with droplet spread. Transmission through fomites or small aerosols cannot be ruled out.  相似文献   
994.
In response to the emergence of severe acute respiratory syndrome (SARS), the United States established national surveillance using a sensitive case definition incorporating clinical, epidemiologic, and laboratory criteria. Of 1,460 unexplained respiratory illnesses reported by state and local health departments to the Centers for Disease Control and Prevention from March 17 to July 30, 2003, a total of 398 (27%) met clinical and epidemiologic SARS case criteria. Of these, 72 (18%) were probable cases with radiographic evidence of pneumonia. Eight (2%) were laboratory-confirmed SARS-coronavirus (SARS-CoV) infections, 206 (52%) were SARS-CoV negative, and 184 (46%) had undetermined SARS-CoV status because of missing convalescent-phase serum specimens. Thirty-one percent (124/398) of case-patients were hospitalized; none died. Travel was the most common epidemiologic link (329/398, 83%), and mainland China was the affected area most commonly visited. One case of possible household transmission was reported, and no laboratory-confirmed infections occurred among healthcare workers. Successes and limitations of this emergency surveillance can guide preparations for future outbreaks of SARS or respiratory diseases of unknown etiology.  相似文献   
995.
996.
We report 49 cases of gallbladder carcinomas that extended into or originated from Rokitansky-Aschoff sinuses (RAS), all of which were resected by laparoscopic cholecystectomy. Twenty-one tumors were in situ carcinomas that extended along RAS; six in situ carcinomas arose in adenomyomatous hyperplasia and 22 were invasive adenocarcinomas with extension into RAS. Thirty-seven patients were women and 12 men. Forty patients had cholelithiasis. The age of the patients ranged from 55 to 84 years (mean 67 years). All in situ carcinomas were incidental microscopic findings in gallbladders removed for cholelithiasis and/or cholecystitis. No patient with in situ carcinoma died as a result of the tumor, including two with in situ carcinoma that originated in adenomyomatous hyperplasia and showed microinvasion. In contrast, of 15 patients with invasive well to moderately differentiated adenocarcinoma extending into RAS and invading the muscle layer or subserosal connective tissue, 8 died 2 to 4 years after surgery. Seven patients survived 1 to 8 years after cholecystectomy. Useful clues to separate RAS with in situ carcinoma from tubular neoplastic invasive glands were the following: connection of the epithelial invaginations to the surface epithelium, recognition of normal biliary epithelium admixed with neoplastic epithelium, presence of inspissated bile in long dilated spaces, and lack of invasion to the smooth muscle bundles. In situ carcinoma spreading along RAS consisted of long tubular often dilated structures extending through the intermuscular connective tissue, whereas neoplastic glands were usually small or of medium size that invaded smooth muscle bundles or intermuscular connective tissue. Perineural invasion was seen only in invasive glands located in the subserosal connective tissue. Two cases of in situ carcinoma that arose in adenomyomatous hyperplasia and three invasive adenocarcinomas that were composed predominantly of tall columnar mucin containing cells similar to gastric foveolar cells with varying degrees of atypia and cells with biliary phenotype bear some resemblance to intraductal papillary mucinous carcinoma of the pancreas or to mucinous cystic pancreatic neoplasm. Metaplastic pyloric glands often seen in the muscle layer and subserosal connective tissue maintain their lobular pattern and should not be confused with invasive glands. Our findings indicate that distinction of in situ carcinoma spreading into RAS from tubular neoplastic glands of invasive adenocarcinomas is crucial to determine prognosis in this group of patients with gallbladder carcinoma.  相似文献   
997.
The treatment of inherited metabolic liver diseases by hepatocyte transplantation (HT) would be greatly facilitated if the transplanted normal hepatocytes could be induced to proliferate preferentially over the host liver cells. We hypothesized that preparative hepatic irradiation (HIR) should inhibit host hepatocyte proliferation in response to partial hepatectomy (PH). Normal nonirradiated hepatocytes transplanted in this setting should have a selective growth advantage over the host liver cells and should progressively repopulate the liver. To test this hypothesis, we transplanted 5 million hepatocytes from normal Wistar-Roman High Avoidance (RHA) rats into the livers of congeneic bilirubin-uridine 5'-diphosphoglucuronate glucuronosyltransferase (UGT1A1)-deficient jaundiced Gunn rats by intrasplenic injection after one of the following treatments: (1) 68% PH, (2) HIR (50 Gy), or (3) HIR + PH. In rats receiving either PH or HIR alone before HT, serum bilirubin concentrations declined by 25% to 30% in 28 weeks. In contrast, serum bilirubin levels were normalized completely in rats receiving HIR + PH before HT. Massive repopulation of the Gunn rat liver by the UGT1A1-positive Wistar-RHA hepatocytes was shown by UGT1A1 enzyme assay, immunoblot analysis, and immunohistochemical staining of the recipient liver. High-performance liquid chromatography analysis of the bile collected from Gunn rats 5 months after PH, HIR, and HT showed normalization of the pigment profile, with bilirubin diglucuronide and monoglucuronide as the predominant pigments. In conclusion, a preparative regimen of HIR + PH results in massive repopulation of the liver with functionally normal transplanted hepatocytes, resulting in complete correction of a metabolic deficiency. Noninvasive strategies to replace PH for providing proliferative stimuli to the transplanted cells should make this regimen valuable in augmenting the effects of HT for the treatment of liver diseases.  相似文献   
998.
OBJECTIVE: To evaluate and describe the epidemiologic characteristics of Kawasaki syndrome (KS) hospitalizations in Georgia. DESIGN: We reviewed hospital discharge data and corresponding medical records for Georgian patients discharged with a KS diagnosis during 1997 and 1998. RESULTS: During the study period, 233 KS hospital discharges were recorded in Georgia; 177 (76%) were for children younger than 5 years. Twenty-one (9%) of 233 of the hospital discharges represented multiple hospitalizations. Medical records for 211 KS discharges (91%), representing 197 patients (93%), were reviewed. For those 189 patients whose medical records were reviewed and had sufficient information, 139 (74%) either had a documented illness that met the Centers for Disease Control and Prevention (CDC) definition for KS (n = 135) or had coronary artery abnormalities without meeting the CDC definition for KS (atypical KS; n = 4). Eight patients had only a history of KS. Excluding multiple hospitalizations and patients with only a history of KS, 158 hospitalizations were for patients younger than 5 years (14.0 per 100 000 children); 110 of these patients met the KS or atypical KS definition (9.8 per 100 000 children). CONCLUSIONS: Hospital discharge data are useful for KS surveillance. However, analysis of hospital discharge data may slightly overestimate the KS hospitalization rates because some discharges may represent multiple hospitalizations or hospitalizations of patients with only a history of KS. The incidence and epidemiology of KS in Georgia are consistent with findings from other continental US studies. Physicians should exercise their best clinical judgment in identifying and treating patients with KS who may not meet standard case definitions.  相似文献   
999.
The long-term effects of ileocolic anastomosis in children are not known. We therefore carried out a survey of all such patients treated at our hospital between 1971 and 1985. Thirty-seven patients were identified and invited to attend for follow-up. Twenty-seven (73 per cent) were examined and included in the survey. Mean age at survey was 7.8 years (range 1.6-17.6 years) and mean duration since operation was 6.3 years. Necrotizing enterocolitis and intussusception were the commonest indications for operation. As judged by height, weight and skin fold thickness, all patients were well nourished. Seven (26 per cent) had loose stools, five had chronic folic acid deficiency and one was vitamin B12 deficient. We conclude that resection of the ileocaecal region is well tolerated in childhood and does not affect growth. Loose stools are directly related to the length of ileal resection.  相似文献   
1000.
Nitazoxanide     
Parashar A  Arya R 《Indian pediatrics》2005,42(11):1161-1165
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