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31.
The epidemiology of Helicobacter pylori infection and risk factors associated with its transmission are not well understood. Kazakhstan is country with two ethnic groups, Asian (Kazakhs) and Western (Russians), living under similar socioeconomic conditions. The aim of this study was to examine the seroepidemiologic pattern of H. pylori and hepatitis A among the same individuals from both ethnic groups, with emphasis on water source and household sanitation practices. This was a cross-sectional seroepidemiologic study conducted among unrelated healthy individuals in Kazakhstan. From May through August 1999, individuals between the ages of 10 and 60 years from Almaty, Kazakhstan, were invited to participate. Demographic information, socioeconomic factors, living conditions, and various aspects of the local household environment including access to water were collected. A clean water index (CWI) was created based on combined factors, consistency of boiling water before drinking, frequency of storing and reusing water, and frequency of bathing and showering. H. pylori and hepatitis A antibodies were assessed by enzyme-linked immunosorbent assay. Two hundred eighty-eight individuals between the ages of 10 and 60 years participated. The prevalence of H. pylori infection was almost identical among the two ethnic groups (Russians 79% and Kazakhs 80%). H. pylori infection was inversely correlated with the CWI (i.e., 56%, 79%, and 95% for high, middle, and low, respectively (P < .05). Drinking river water had highest risk of H. pylori infection (OR = 13.6, 95% CI = 1.8-102.4; P < .01, compared with tap water). Crowding showed no significant effect on H. pylori prevalence. Anti-HAV antibodies were found in 86% of the population, 90% among the Russians versus 82% among the Kazakhs (OR = 1.8, 95% CI = 1.1-3.8, P = .05). Although the two infections were highly correlated (P < .001), antibody to both infections were present simultaneously in only 74%. The prevalence of H. pylori infection in Kazakhstan is very high. The data suggest that transmission of H. pylori can be water borne, related to poor sanitary practices, or both. The high prevalence of antibodies to H. pylori and HAV among this population is a marker for poor sanitation and hygienic practices. Reducing the rate of H. pylori transmission will require improvements in overall sanitation including clean water, waste disposal, as well as in household hygienic practices.  相似文献   
32.
ABSTRACT. The association of zinc and vitamin A levels was studied in liver of foetuses and infants which were stillborn or died of various causes between the age of 26 weeks of gestation up to 16 weeks post-partum. No correlation between zinc and vitamin A was observed ( r =0.07). Although smaller infants had more hepatic vitamin A than larger infants no significant difference was observed between these groups for liver zinc values.  相似文献   
33.
Regulators of G protein signaling (RGS) and RGS-like proteins are a family (>30 members) of highly diverse, multifunctional signaling proteins that bind directly to activated G alpha subunits. Family members are defined by a shared RGS domain, which is responsible for G alpha binding and markedly stimulates the GTPase activity of G alpha subunits leading to their deactivation and termination of downstream signals. Although much has been learned in recent years about the biochemistry of RGS/G alpha interactions, considerably less is known about the broader cellular roles and regulation of RGS proteins. Recent findings indicate that cellular mechanisms such as covalent modification, alternative gene splicing, and protein processing can dictate the activity and subcellular localization of RGS proteins. Many family members also directly link G proteins to a growing list of signaling proteins with diverse cellular roles. New findings indicate that RGS proteins act not as dedicated inhibitors but, rather, as tightly regulated modulators and integrators of G protein signaling. In some cases, RGS proteins modulate the lifetime and kinetics of both slow-acting (e.g., Ca(2+) oscillations) and fast-acting (e.g., ion conductances, phototransduction) signaling responses. In other cases, RGS proteins integrate G proteins with signaling pathways linked to such diverse cellular responses as cell growth and differentiation, cell motility, and intracellular trafficking. These and other recent studies with animal model systems indicate that RGS proteins play important roles in both physiology and disease. Recognition of the central functions these proteins play in vital cellular processes has focused our attention on RGS proteins as exciting new candidates for therapeutic intervention and drug development.  相似文献   
34.
New trends in pediatric anesthesia for ambulatory surgery will be described. Preoperative preparation as well as care of pediatric patients requiring sedation outside of the operating room are emphasized.  相似文献   
35.
Kim AW  McCarthy WJ  Maxhimer JB  Quiros RM  Hollinger EF  Doolas A  Millikan KW  Deziel DJ  Godellas CV  Prinz RA 《Surgery》2002,132(4):738-44; discussion 744-7
BACKGROUND: Early survival after pancreaticoduodenectomy has improved, but its morbidity remains high. The purpose of this study is to determine how the intra-operative (OR) occurrence of major vascular complications affects the outcome of pancreaticoduodenectomy. METHODS:The medical records of 180 consecutive patients having pancreaticoduodenectomy from 1991 to 2001 were reviewed. Vascular complications were defined as "an unanticipated injury or thrombosis of a major vessel necessitating intervention." Age, sex, type of pancreaticoduodenectomy, tumor size, estimated blood loss, OR time, time in intensive care, post-OR hospitalization, and survival were compared. RESULTS: Eighteen vascular complications were identified. Differences in age, sex, and type of resection between patients with or without vascular complications were not significant. OR time, estimated blood loss, blood transfusions, tumor size, time in intensive care, and post-OR hospitalization were all significantly greater in patients with vascular complications. Median survival for patients with vascular complications was significantly shorter than for patients without vascular complications. Thirty-day mortality was greater in patients with vascular complications. CONCLUSION: Vascular complications significantly affect the outcome of pancreaticoduodenectomy increasing OR time, estimated blood loss, blood transfusion requirements, time in intensive care, post-OR hospitalization, and mortality.  相似文献   
36.
This study demonstrates interfacial changes of titanium miniplate/screw with normal calvaria and nonvascularized calvarial bone graft ensued from craniectomy in a 53-year-old female. In 18 months after operation, a right parietal bone containing an L-shaped miniplate with screws, 5 mm long and 2 mm in external diameter, was harvested, fixed, and embedded in methylmetacrylate. Fifteen micrometer thick sections were made by an EXAKT cutting-grinding system (Exakt Company, Hamburg, Germany), and reviewed under the bright field light microscope. The mean of the bone-contacting surface ratio (BCSR) in six screwed bone was 64.1%; 69.3% in normal bone, and 60.4% in grafted bone. The trabecular bone areas in 10 x 5 mm (50 mm2) rectangular area of diploe surrounding the screws was 43.02 mm2; 45.25 mm2 in normal calvaria; and 41.82 mm2 in grafted bone. The mean Ca/P peak-height ratio of the plated and screwed calvaria was 1.47 in a 9 mm wide zone around each screw; 1.37 in normal calvaria; and 1.51 in grafted calvaria. We concede that the effect of direct contact of titanium with screws onto the bone is as much as an osseous integration (osseointegration).  相似文献   
37.
Forty one (1%) of 4000 children referred for respiratory disease had chronic suppurative lung disease not due to cystic fibrosis. Further investigations showed congenital malformations in six (15%), primary ciliary dyskinesia syndrome in seven (17%), 11 had immunological abnormalities (27%), and two bronchiectasis due to aspiration (5%). Therefore the underlying cause for the disease was found in 63%. Identification of predisposing causes may facilitate prevention of further bronchial damage.  相似文献   
38.
This paper describes a teaching programme, for use in general practice vocational training, which provides a theoretical and practical framework for exploring key aspects of the consultation with trainees. A particular emphasis is on the educational or 'cognitive' outcomes of the consultation and skills for improving them. The five stages of the programme are described and an example of experience of each stage is given. The paper concludes with an evaluation of the programme by the trainers, trainees and social scientist involved.  相似文献   
39.
In the summer of 1966, an epidemic of St. Louis encephalitis occurred in Corpus Christi, Texas, coincident with one occurring in Dallas about 563 km to the north. Among the 76 cases confirmed in Corpus Christi, there were two deaths; the attack rate was 41.0 per 100,000. In contrast with a concurrent outbreak in Dallas and the 1964 outbreak in Houston, attack rates were much higher in populations of the upper socioeconomic districts. This distribution may have resulted from the combined effects of an unusual concentration of vector mosquito breeding sites in storm sewers in the upper socioeconomic districts and a higher degree of residual immunity in the residents of the lower socioeconomic areas.  相似文献   
40.
The effects of treatments with diethylnitrosamine (DENA) and hepatitis B virus (HBV) on macaque monkeys were investigated by virus serology and by light and electron microscopy. The experimental groups comprised 43 newborn or juvenile cynomolgus and rhesus monkeys of both sexes. HBV neither had a carcinogenic effect nor increased the oncogenic effect of DENA. However, HBV given to juvenile primates before treatment with DENA resulted in subsequent gross and microscopic alterations consistent with mild hepatitis and postnecrotic cirrhosis; multifocal liver carcinoma apparently developed within these cirrhotic nodules. The pathologic findings in the experimental animals were strikingly similar to those observed in liver cancer patients.  相似文献   
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