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991.
M K Schwaber  J W Hall 《The Laryngoscope》1992,102(9):1020-1029
Cochleovestibular nerve compression syndrome (CNCS) is the term used to describe a group of audiovestibular symptoms thought to be due to a vessel compressing the cochleovestibular nerve. These symptoms include recurrent vertigo, continuous disequilibrium and acquired motion intolerance. Recently, Moller reported that CNCS can be diagnosed based on abnormalities in the auditory brainstem response (ABR). After specifically excluding all other vestibular disorders, 63 patients with symptoms suggestive of CNCS were identified. These patients were systematically evaluated with a standard neurotologic test battery, and the results were reviewed retrospectively. Hearing loss was found in 51 (81%) of 63 cases, including 33 cases of unilateral high-frequency loss and 14 cases of middle-frequency loss. ABR data were interpreted with respect to Moller's criteria, and abnormal studies were found in 42 (75%) of 56 cases. Abnormal electronystagmograms were found in 57 (93%) of 61 cases. Thirteen of the patients subsequently underwent a posterior fossa procedure for vertigo and, vessels were found in contact with the cochleovestibular nerve in 11 of 13 cases. The results of this study suggest that the majority of CNCS patients have neurotologic test findings that suggest an abnormality of the cochleovestibular nerve. The results and their implications are discussed.  相似文献   
992.
A prospective study of the clinical and epidemiological features of the haemolytic uraemic syndromes was conducted over a three year period in the British Isles. Two hundred and ninety eight children were reported. In two thirds of cases stool samples were analysed for the presence of Verocytotoxin producing Escherichia coli (VTEC) and neutralisable Verocytotoxin. A total of 273 (95%) patients had a prodrome of diarrhoea. In these a seasonal variation in the incidence of haemolytic uraemic syndrome was demonstrated, the 1-2 year age range was most often affected, and the peripheral blood neutrophil count correlated positively with an adverse outcome. Patients presenting without diarrhoea showed none of these associations and had a significantly greater morbidity and mortality. Evidence for VTEC infection was found in 58 (33%) of 178 diarrhoea associated cases whose stools were analysed, although VTEC were identified in five of eight (62%) patients whose stools were collected within three days of the onset of diarrhoea. Most isolates produced VT2 either alone, or together with VT1. There was no evidence of VTEC infection in patients without prodromal diarrhoea.  相似文献   
993.
An infant girl had the clinical and immunologic findings of congenital rubella syndrome but also had arthrogryposis multiplex and calcific epiphyseal stippling. Spastic quadriparesis developed, and both physical and behavioral development were slow. Increased spasticity of the legs at 5 1/2 years was related not to progressive rubella encephalomyelopathy but to spinal cord compression by abnormal cartilaginous tissue. The presence of a peroxisomal disorder was demonstrated by a greatly increased level of phytanic acid and slightly increased levels of hexacosanoate in serum and by reduced activity of peroxisomal dihydroxyacetone phosphate acyltransferase and a slightly increased ratio of cytosolic to peroxisomal catalase activity in cultured fibroblasts. A reduction in the number and size of peroxisomes was demonstrated in cultured fibroblasts, and a needle biopsy specimen of the liver also showed the peroxisomes to have a smaller diameter than usual. We recommend that any child with epiphyseal stippling be assessed for peroxisomal disease and that the potential for spinal cord compression by dysplastic bone or cartilage be recognized. The association of peroxisomal dysfunction with congenital rubella has not been described previously. The interaction between rubella virus infection and peroxisomal function may need further investigation.  相似文献   
994.
Using the polymerase chain reaction with degenerate oligonucleotides derived from conserved motifs within the catalytic kinase domain of protein tyrosine kinases, and RNA extracted from embryonic stem cells, sequences that encode a segment of the kinase domain of several potentially novel receptor tyrosine kinases (RTKs) have been identified. One of these was selected for further study because in Northern analysis it hybridized to RNA from multipotential hematopoietic cell lines, but not from lines representative of lineage-committed cells. A cDNA for this receptor, designated developmental tyrosine kinase (DTK), was isolated and encodes a protein with structural similarities to AXL. Together these receptors form a new class of RTK. DTK is expressed in a number of human leukemic cell lines, and in the blasts of 6 of 11 patients with acute myeloid leukemia (AML) analyzed. The structure of DTK suggests that it may function as a cell adhesion molecule, and mediate cell-to-cell or cell-matrix interactions between hematopoietic cells and their respective microenvironments.  相似文献   
995.
The Stockholm-Gotland Cancer Register was used to evaluate the clinical observation that patients with non-Hodgkin's lymphoma (NHL) had an increased risk of malignant melanoma or squamous-cell carcinoma of the skin (SCCS) and vice verso. During 1958–1992, NHL was diagnosed in a total of 6,176 patients. Of these patients, 504 developed a second primary cancer of any type except NHL, compared to 301.9 expected, giving a standardized incidence ratio (SIR) of 1.7 [95% confidence interval (Cl) 1.5–1.8]. The risk of SCCS and malignant melanoma in patients with NHL was 4.8 (95% Cl 3.6–6.2; n = 54) and 1.7 (95% Cl 0.8–3.1; n = 10), respectively. The hazard risk for a second malignancy was relatively constant over time, whereas the skin malignancies revealed the highest risks 3–10 years after initial diagnosis. Similarly, the risk of a secondary NHL was studied in patients with malignant melanoma and SCCS during the same period and found to be 1.3 (95% Cl 0.8-2.1; n = 17) and 1.8 (95% Cl 1.2–2.5; n = 34), respectively. The highest risk for NHL following malignant melanoma was seen 3–10 years after first diagnosis, while the highest risk following SCCS was observed 0-2 years after initial diagnosis. One of several possible explanations for the development of NHL and a skin malignancy in the same patient is an immunological defect caused by sun exposure. © 1995 Wiley-Liss, Inc.  相似文献   
996.
OBJECTIVE: To assess the cost-effectiveness of adding school based Mantoux screening programs to the New South Wales current TB prevention strategy. METHOD: A decision analysis model compared the costs and consequences of screening strategies against the current no-screen strategy. Costs associated with screening and with treating future cases of TB were considered. Consequences considered were deaths and adult cases of TB prevented. The study was based on data from prevalence surveys conducted in 1992 and 1994 in Central and South Western Sydney, New South Wales. Screening strategies considered were screening all or only overseas born (OSB) 6 year olds and all or only OSB 14 year olds in school settings. RESULTS: Screening 14 year olds prevented more deaths and adult cases of TB than screening 6 year olds for a similar cost. For both age groups targeted screening of OSB children was more cost-effective than screening all children. Targeted screening of 14 year olds--the most cost effective option--cost $17,956 (costs and benefits discounted at 5%) per adult case prevented, equivalent to approximately $130,000 per life year saved. The cost-effectiveness ratios decline substantially if lower discount rates and less conservative assumptions are applied. CONCLUSION: Targeted screening was more cost effective than screening all children, however, there are ethical implications of targeting a group based on their origin of birth. IMPLICATIONS: As prevention and control of TB continues to be a high priority for NSW, the implications of a school based screening program should be seriously considered.  相似文献   
997.
Over the three years period 1980-1982, 18 256 pregnancies in the Grampian Region of N-E Scotland including the islands of Orkney and Shetland were screened for raised levels of maternal serum alpha fetoprotein (MSAFP) in the second trimester. Thirty six cases of fetal open neural tube defect in singletons were detected (18 anencephaly and 18 spina bifida). Four additional cases of open spina bifida were associated with normal MSAFP levels although two of these were detected by amniotic fluid AFP measurement when amniocentesis was carried out because of previous NTD history. A further three cases of open spina bifida and two of anencephaly occurred in unscreened pregnancies. The MSAFP screening programme alone was thus instrumental in reducing the birth incidence of open neural tube defects by 36 out of 45 cases (80 per cent) in singletons.  相似文献   
998.
Selective intra-arterial streptokinase therapy successfully reopened ten axillofemoral and lower extremity Dacron bypass grafts that had undergone delayed closure from two to 47 months after implantation. In four, completion arteriograms revealed no runoff obstruction acquired since implantation; additional runoff obstruction had developed in the remaining six. All of the grafts without obstruction have remained open from two to 11 months. Three of the six grafts with obstruction have remained open from two and one-half to four months after specific surgical correction of the obstructive lesion. We conclude that intra-arterial streptokinase therapy is an effective means to reopen knitted Dacron grafts that have undergone delayed closure in the axillofemoral and above-knee femoropopliteal positions.  相似文献   
999.
First-look laparoscopy (FL) on the eighth day after salpingostomy, fimbrioplasty, or adhesiolysis was performed in 188 patients. Behavior of postoperative adhesions and the occurrence of pregnancy after tubal surgery were compared with a similar group of 127 patients in whom no FL was performed. In greater than 50% of the cases (104/188), adhesions were found on the eighth postoperative day around both adnexa or the only remaining adnexum. Adhesions were mainly located between the ampulla and the ovary and between the ovary and the lateral pelvic wall or broad ligament. More than half of the adhesions that were separated at FL did not recur. It was concluded that FL significantly diminished the occurrence of permanent pelvic adhesions. The incidence of ectopic pregnancy after salpingostomy was significantly lower when FL was performed. FL on the eighth postoperative day can be regarded as a well-accepted procedure with few complications.  相似文献   
1000.
Wegener granulomatosis in pediatric patients   总被引:1,自引:0,他引:1  
Wegener granulomatosis is more easily recognized as a distinct clinical entity than other vasculitides because the initial clinical features frequently include granulomatous vasculitis of the upper and lower respiratory tract and glomerulonephritis. Although the disease has been lethal in the past, prolonged survival and avoidance of end-stage kidney disease can now be expected when cyclophosphamide therapy is introduced early in the course. We report four children with Wegener granulomatosis in whom the initial clinical findings suggested Henoch-Sch?nlein purpura. In two of the patients Wegener granulomatosis was not recognized until after end-stage kidney disease had developed. The course in these patients emphasizes the need for attention to even scant evidence of inflammation of the upper or lower respiratory tract in patients with glomerulonephritis. Appropriate diagnostic studies may then lead to recognition of Wegener granulomatosis and the prompt institution of appropriate treatment.  相似文献   
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