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Familial adenomatous polyposis (FAP) is characterized by the presence of premalignant adenomas of the large and small bowel. Prophylactic colectomy deals with the risk for colon cancer, leaving duodenal cancer as the leading cause of death. Although most FAP patients have duodenal adenomas, only approximately 5% develop duodenal cancer. This study looks at progression of duodenal polyps with time. The outcome of endoscopic surveillance in the duodenum of 70 patients with familial adenomatous polyposis was determined. A mean of 40 months elapsed between endoscopies. Outcome was measured using video comparison and a staging system that includes histological assessment. Duodenal cancer developed in one patient, and was suspected in two others. The stage of duodenal polyposis worsened in another seven patients. When histology was ignored, comparison of video recordings in 52 patients showed a worsening in 21 (40%). In conclusion, further surveillance appears warranted so that patients at high risk for duodenal cancer might receive early treatment. Should slow progression of duodenal polyposis be shown to be associated with low risk, then most patients can be safely offered less frequent endoscopies than hitherto.  相似文献   
43.
Background: The role of intraoperative fluorocholangiography (IOC) in laparoscopic cholecystectomy (LC) is controversial. We evaluated the use of IOC at an institution where the study is performed routinely. Methods: Records of all patients undergoing LC during a 3-year period ending January 1, 1996 were reviewed. Results: A total of 1207 patients received IOC, whereas 116 patients did not. IOC findings were categorized as follows: normal, 1016 cases (84%); CBD stone, 149 cases (12.3%); anomalies, 23 cases (1.9%); duodenal diverticula, 10 cases (0.8%); ductal strictures, four cases (0.3%); and CBD diverticula, 5 cases (0.4%). In the 116 patients who did not receive IOC, 35 of the procedures could not be performed, whereas 81 were not attempted. Of the 149 IOC that showed CBD stones, two were false positives. Anomalies included accessory right hepatic ducts (11 cases), cystic ducts joining the right hepatic duct (seven cases), and abnormal cystic duct entries (five cases). Duct injuries occurred in 5 cases (0.4%), three before and two after IOC. Four injuries were minor; IOC prevented CBD transection. Conclusions: Routine IOC is feasible, safe, accurate, and provides critical information of immediate use during LC. By treating ductal stones at operation and identifying patients without CBD stones, IOC minimizes need for postoperative studies, including endoscopic retrograde cholangiography (ERC).  相似文献   
44.
The amygdala is considered to be a critical neural substrate underlying the formation of stimulus-reward associations, and is known to receive substantial innervation from dopaminergic neurons located within the ventral mesencephalon. However, relat- ively little is known about the function of the mesoamygdaloid dopamine projection in stimulus-reward learning. Recently, we have found post-session intra-amygdala microinjections of d-amphetamine to enhance appetitive Pavlovian conditioning as assessed in a discriminative approach task. In the present study, we have examined the effects of dopamine receptor agonists possessing relative selectivity for the D1, D2 and D3 receptor subtypes in order to examine more fully the role of the mesoamygdaloid dopamine projection in stimulus-reward learning. Thus, subjects were trained to associate an initially neutral stimulus (CS+) with 10% sucrose reward (US). A second, control stimulus (CS) was also presented but never paired with sucrose reward. In order to measure specifically the conditioned response to CS+/CS presentation, responding during CS and US presentations was measured separately. Immediately following each training session, subjects received bilateral intra-amygdala infusion of 0.1, 1 or 10 nmol/side of SKF-38393, quinpirole or 7-OH-DPAT. Infusions of SKF-38393 or quinpirole were without effect on CS+ approach. However, post-session intra-amygdala infusions of 7-OH-DPAT enhanced selectively CS+ approach in a dose-dependent fashion. No dose of any drug affected CSapproach, US behaviours, or measures of extraneous behaviour. Subsequent acquisition of a novel conditioned instrumental response was also unaffected. Thus, the present data indicate a selective involvement of the D3 dopamine receptor subtype in the modulation of stimulus-reward learning by the mesoamygdaloid dopamine projection. Received: 12 December 1996 / Final version: 9 April 1997  相似文献   
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The clinicopathologic features of 17 cases of an unusual variant of chorioamnionitis distinguished by a pure or predominantly chronic inflammatory infiltrate in the fetal membranes rather than the usual acute inflammatory reaction are reported. In six cases, there was an equal (one case) or minor (five cases) component of acute inflammation in the fetal membranes as well. Concomitant villitis, found in 11 cases, was almost uniformly lymphohistiocytic and destructive, but it varied greatly in severity. Immunoperoxidase stains for cytomegalovirus, herpes simplex I and II, and Toxoplasma gondii; Warthin-Starry, Gomori methenamine silver, Dieterle, Gram and acid fast stains; placental or amniotic fluid culture; and limited maternal serologic studies failed to identify a specific infectious etiology in any case. Seven women had experienced at least one previous spontaneous abortion, fetal death in utero, or preterm birth. No patient reported a history of fever, rash, or flu-like syndrome during pregnancy. Serious antenatal complications were numerous. Preterm birth occurred in 13 cases. Gestational age ranged from 25 to 42 weeks (mean 32 weeks) and birth weight ranged from 740 to 3,230 g (mean 2,100 g). When expressed as a percentile for gestational age, 47% of infants had a birth weight at or below the 25th percentile, and 76% were at or below the 50th percentile. Two infants were born with gross anomalies, and one infant died in the neonatal period.  相似文献   
47.
In order to determine the effects of the Fowler-Stephens orchiopexy (FSO) on fertility, young rats underwent simulated FSO, FSO and concurrent contralateral orchiectomy (FSO/OR), unilateral orchiectomy (OR), or sham operation (controls). Twelve weeks after the operation, each male rat was mated to two proven-fertile female rats for 17 days (three ovulatory cycles). Two weeks later, both male and female rats were killed. No pregnancy resulted from the matings of the FSO/OR males. In contrast, pregnancy ensued in 13 of 16 (81%) females in the FSO group, 9 of 14 (64%) in the OR group, and 11 of 12 (92%) in the control group. There were no fertile males in the FSO/OR group. In the FSO group, eight of eight males induced pregnancy in at least one female; in the OR group, six of seven (86%) males were fertile as were all six males in the control group. No differences in litter size or fetal weight were observed between fertile females in various groups.  相似文献   
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49.
A new technique in the treatment of stress urinary incontinence utilizes a sling fashioned from a rectangular island of buried vaginal epithelium. We developed a model to study the natural history of vaginal wall covered by an epithelial flap in 12 rabbits sacrificed at intervals to 26 weeks. Histopathologic examination demonstrated an immediate acute inflammatory reaction. This early response was followed by formation of an epithelial lining of the potential space overlying the buried vaginal tissue. Acute inflammatory cells continued to enter this lumen until week 20, when granulomas were first detected. Histopathologic examination at twenty-six weeks showed stratified squamous epithelium lining the lumen. No deleterious inflammatory sequelae were detected, and no dysplastic or malignant changes were identified. These results suggest that buried vaginal epithelium is a safe (short term) tissue alternative for sling creation.  相似文献   
50.
Laparoscopic trans-cystic-duct common-bile-duct exploration   总被引:1,自引:0,他引:1  
One thousand seventy-one consecutive laparoscopic cholecystectomies were performed. Routine cholangiography was employed with a 99% success rate. One hundred thirty patients were found to have common duct stones (CBDS). In 48 (37%) patients they were unsuspected. One hundred eleven patients underwent attempted trans-cystic-duct extraction techniques (TCD-CBDE). One hundred three (93%) were successful. The following techniques were employed: 101—biliary endoscopy, 23—ampullary balloon dilation, 2—fluoroscopic basket retrieval.The average operative time was 136 min. The average postsurgical stay was 3.7 days. There were 19 (17%) complications—6 (5%) major. There were 4 retained stones (2 intentional) and 1 death. Patients over 65 years of age had more complications and patients with unsuspected CBDS under 65 years of age had the fewest.TCD-CBDE is a safe, effective way to extract common duct calculi. Endoscopy and basket stone retrieval was the primary technique employed.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, Tennessee, USA, 18–19 April 1994  相似文献   
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