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91.
The purpose of this study was to examine driving as a determinant of hand and foot psychomotor reaction times. Visual simple and choice hand and foot psychomotor reaction times were measured. The occupational driving contrast was determined by an interview reviewing every job held during each subject's lifetime. Comparison was made of psychomotor speed among 18 pairs of 39- to 62-year-old monozygotic male twins discordant for lifelong occupational driving. The mean discordance was the equivalent of 16 years of full-time driving. The twins who drove more tended to have slower hand simple and choice reaction times, although only the difference in hand-choice decision time was statistically significant (32 ms, P<0.05). The drivers also had slower ipsilateral foot-choice decision times (21 ms, P<0.01), but on average they had faster reaction times in 8 of the 12 ipsilateral and contralateral foot measurements. The slightly longer decision times could be related to some general harmful effects of driving, possibly whole-body vibration. Faster foot movement times of drivers may be affected by practice effects of rapid lower-extremity movements in driving. Received: 24 September 1996 / Accepted: 30 April 1996  相似文献   
92.
The presence of Streptococcus pneumoniae in the upper respiratory tract was studied in 318 Filipino children less than 5 years old with an acute lower respiratory tract infection. Nasopharyngeal samples were obtained from 292 children. With both quantitative bacterial culture and detection of capsular polysaccharide antigens by coagglutination, counterimmunoelectrophoresis, and latex agglutination, pneumococci were found in 160 (70%) of the 227 samples eligible for analysis. Culture was positive in 115 samples and antigen was positive in 140 samples. The culture isolation rate was significantly lower if the patient had received antimicrobial agents in the 48 h prior to the sampling. The seven most common types or groups of pneumococci were 6, 14, 19, 23, 15, 7, and 11, which together accounted for 64% of all pneumococcal findings.  相似文献   
93.
Lymphocyte subsets in the cerebrospinal fluid in active multiple sclerosis   总被引:1,自引:0,他引:1  
We studied the relative number of lymphocyte subsets in the cerebrospinal fluid (CSF) of patients with active multiple sclerosis. The cells were double-labeled with monoclonal antibodies and were studied using a fluorescence-activated cell analyzer. The number of Leu2+Leu15+ cells and Leu3+Leu18+ cells was markedly reduced in the CSF but not in the peripheral blood of the patients. The number of Leu3+Leu18+ cells was reduced also in the CSF of control patients (patients with other inflammatory or infectious neurological diseases).  相似文献   
94.
Summary Antisera against a variety of substances have been found to produce an identical immunoreaction in the developing olfactory system of a teleost, the three-spined stickleback (Gasterosteus aculeatus). The label is localized in the olfactory placode, the olfactory nerve and those parts of the secondary olfactory tracts which constitute the dorsal descending fascicles and the ventral descending fibers of the medial olfactory tract. The label was first detected 3 days after fertilization (3D) in the olfactory placode where labeled supporting cells were observed. At 4D, the label was observed at the site of the developing olfactory bulbs. At 7D, the olfactory placode lost the direct contact with the brain and the labeled olfactory nerve became visible. At the same time, the medial olfactory tract emerged from the bulbs, and contacts with cells in the nucleus of the terminal nerve were observed. The development of the medial olfactory tract proceeded caudally, and by the end of I OD, the olfactory tract reached the periventricular hypothalamus. Pre-absorption of the antisera with the respective antigens did not abolish the capacity of the antisera to produce the label. The immunoreaction is thus not specific for the antigens against which the antisera have been raised. Yet the label produced by the immunoreaction is an extremely reliable marker for the primary olfactory tract, and the only existing marker by which secondary olfactory tracts can be visualized.  相似文献   
95.
In order to obtain a reproducible experimental model of osteoarthritis a method of immobilizing the rabbit's knee in extension by means of a plastic splint was developed. The right knees of the rabbits were immobilized for periods varying from 4 days to 24 weeks. With the left knees as controls the knees were studied in a variety of ways among these being radiography (126 rabbits), histological sections stained with Alcian Blue (88 rabbits), analysis of 35S-sulphate uptake (22 rabbits) and 35S-autoradiography (6 rabbits). In 27 rabbits the regaining of mobility after immobilization was studied. After 5-6 weeks of immobilization most of the knees showed moderate or severe changes including loss of articular cartilage and osteophyte formation. Immobilization of the rabbit's knee by this method provokes a fairly easily reproducible type of degenerative joint disease showing similarities to advanced osteoarthritis as seen in humans.  相似文献   
96.
The role of adverse drug reactions (ADRs) as a cause of hospital visits varies depending on the type of hospitals. Our aim was to determine the incidence of drug-related emergency department visits to a district hospital, and to identify the drugs and patient groups involved. All patient visits to the emergency department of a Finnish district hospital were evaluated prospectively for 6 months. The physician on duty and a clinical pharmacologist selected all possibly drug-related visits for further scrutinising. The causality assessment (drug-related or not) was judged according to WHO criteria, based on the patients' files, including laboratory and other data. Of the 7113 evaluated visits, 167 (2.3%) were "certainly" or "probably" drug-related; 102 (1.4% of all) were related to ADRs and 65 (0.9%) to intentional overdoses. The most common ADRs were gastrointestinal symptoms (n=17) caused by antibiotics, opioids, nonsteroidal antiinflammatory or cytostatic drugs. The International Classification of Disease (ICD-10) codes on patients' files were insensitive to disclose ADRs. The ADR patients were older (mean age 57 years) than the intentional overdose patients (38 years; P<0.001). Males predominated in the intentional overdose group (38 males, 27 females) but not in the ADR patients. The majority of intentional overdoses was caused by psychotropics. The ADRs lead to hospitalisation in a higher frequency (51%) than did the intentional overdoses (35%). In conclusion, the incidence of "certainly" or "probably" drug-related visits to the district hospital emergency room was relatively low. The ICH-10 codes on patients' files were found to be insensitive to disclose the ADRs, even when they lead to hospital admission, casting doubts on the usefulness of ICH codes alone in ADR evaluation.  相似文献   
97.
BACKGROUND: Mechanisms, other than gene amplification, leading to overexpression of AR in androgen ablation-resistant prostate cancer remain unknown and could include genetic alterations in the promoter or untranslated regions (UTR) of the AR gene. MATERIALS AND METHODS: DNAs from five prostate cancer cell lines, 19 LuCaP xenografts, 44 clinical tumors, and 36 non-malignant controls were used for screening mutations in the upstream regulatory region, promoter and the 5'- and 3'-UTRs of the AR gene with denaturating high performance liquid chromatography (DHPLC) and sequencing. RESULTS: Ten different sequence variations were found in prostate cancer cell lines and xenografts. However, none of them were recurrent or were found in clinical prostate cancer specimens or in normal controls. CONCLUSIONS: Recurrent mutations in the promoter or UTRs of AR seem to be rare, and thus not likely mechanisms for the increased expression of the gene in the androgen ablation-resistant prostate cancer.  相似文献   
98.
OBJECTIVES: To evaluate the frequency of the urokinase-type plasminogen activator (uPA) gene amplification and the sensitivity of prostate cancer cells to uPA inhibition, as we previously found one hormone-refractory prostate tumour with high-level amplification of the uPA (alias PLAU) gene, and also showed that a uPA inhibitor, amiloride, can effectively reduce the invasion potential of the PC-3 prostate cancer cell line. MATERIALS AND METHODS: Sixty-three locally recurrent hormone-refractory tumours and 78 hormone-refractory metastases from 29 patients who died from prostate cancer were analysed for uPA gene-copy number using fluorescence in situ hybridization. The Matrigel invasion assay was used to study the influence of uPA inhibitors on the invasive potential of prostate cancer cell lines. RESULTS: Of the locally recurrent hormone-refractory tumours, 21% had an increased copy number of uPA, but no high-level amplifications were found; 31% of the metastases had increased copy number and one high-level amplification of the uPA. Matrigel invasion assays with two specific uPA inhibitors, B428 and p-aminobenzamidine, showed that invasion of a prostate cancer cell line containing uPA gene amplification was inhibited by these small-molecule uPA inhibitors, while invasion of prostate cell lines without uPA gene amplification were not. CONCLUSION: These results suggest that selective inhibition of the uPA pathway in individuals whose tumours contain uPA gene amplification may provide therapeutic benefit.  相似文献   
99.
Less than 10% of cardiac myxomas are familial. These familial cases are related to Carney complex, a multiple neoplasia and lentiginosis syndrome. Mutations in the PRKAR1alpha gene are the cause of Carney complex in most patients. We report a boy, who had PRKAR1alpha gene mutation, and atrial myxoma that was diagnosed in a routine echocardiographic study at the age of four years. Surgical excision of myxoma was performed. This case demonstrates the benefit of screening genetically the kindreds of patients with familial myxomas, and the importance of close follow-up of individuals affected with this mutation irrespective of age.  相似文献   
100.
We studied the impact of liver echogenicity among other potential predictors of systemic blood pressure (BP) and the metabolic syndrome. 38 persons (32 males, six females, aged 29 to 66) had their liver echogenicities scored, BPs measured and standard serum laboratory tests studied. There was a significant correlation between both systolic (r=0.438, p=0.006) and diastolic (r=0.498, p=0.001) BP and liver echogenicity. Liver echogenicity was the strongest predictor for systolic BP and the second strongest (after body mass index, BMI) for diastolic BP. Body height may modify the relation between liver echogenicity and systolic BP. Liver echogenicity also correlated significantly with BMI (r=0.527, p=0.001), serum triglycerides (r=0.472, p=0.003) and, to a lesser degree, with serum total cholesterol (r=0.305, p=0.066). Incidentally found increased liver echogenicity should alert the US performer and the clinician reading the report on the possibility of elevated BP or other features of the metabolic syndrome.  相似文献   
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