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991.
Acute megakaryocytic leukemia in children. Clinical, immunologic, and cytogenetic findings in two patients. 总被引:2,自引:0,他引:2
An unusual presentation of acute megakaryocytic leukemia (AMKL) is reported in two young children. The first child had a 10-day history of ptosis of the right eyelid as the initial manifestation of AMKL, a clinical picture not previously described in this variant of leukemia. Computed tomographic scanning showed multiple intracranial mass lesions, and the diagnosis of AMKL was confirmed by immunophenotyping of bone marrow blasts. The second child had Down syndrome and received alkylating agents and radiation therapy for treatment of metastatic rhabdomyosarcoma of the orbit. She had AMKL as second malignancy. Both patients had acquired chromosome 21 anomalies in their leukemic blasts. The first patient, constitutionally normal, had an i(21q) in his leukemic blasts; the patient with constitutional trisomy 21 had tetrasomy 21 and additional chromosomal changes. The clinical symptoms and the results of morphologic, immunologic, and cytogenetic studies are discussed. 相似文献
992.
M F Wolf U Koerner B Klumpp K Schumacher 《International journal of cancer. Journal international du cancer》1987,40(6):788-791
The molecules involved in homotypic aggregation of the human Burkitt-lymphoma cell line Raji were investigated by inhibition of reaggregation with carbohydrates and glycoconjugates, by inhibition of glycosylation, and enzyme treatment of the cell surface. Complete inhibition of reaggregation was achieved with bovine submaxillary mucin. Asialomucin, on the other hand, was not effective in this assay. Another potent inhibitor of reaggregation was the ganglioside GMI. The common carbohydrate structure of these molecules is NeuNAc-(gal)-galNAc. Lactosamine, fucosyllactosamine, sialyllactosamine, complex mannose type, or Thomsen-Friedenreich antigen sequences are not involved in aggregation. Neuraminidase and chloroquine also abolished agglutination of cells. The finding that mucin, but not asialomucin, inhibits the reaction, demonstrates the importance of sialic acid in this process. Homotypic aggregation was shown to be resistant to trypsin. Using the glycosylation inhibitor tunicamycin we show that N-glycosidically linked carbohydrate chains are involved in aggregation. Swainsonine or castanospermine, which inhibit processing of terminal sialyllactosamines to the mannose core, did not interfere with the reaction supporting the results of the inhibition assay. The data presented suggest the involvement of 2 molecules in homotypic aggregation of human Burkitt-lymphoma cells. One component is a lectin-like molecule containing N-linked carbohydrate chains. The other component carries the neuraminidase-sensitive and trypsin-resistant determinant NeuNAc-(gal)-galNAc and, therefore, appears to be a glycolipid. This proposed lectin-carbohydrate interaction in homotypic aggregation is further supported by the frequently observed dependence of lectins on divalent cations as indicated by inhibition of aggregation with EDTA and EGTA. 相似文献
993.
In a major uroflow study new variables are introduced to meet the needs, and to use the possibilities of automatic processing of uroflow signals. It is found that the new variables provide excellent discrimination between male and female patients with bladder outflow impairment and healthy controls. In comparison to some conventional variables they have the advantage of unambiguous determination and low sensitivity to random measurement errors. 相似文献
994.
995.
U Trenckmann 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1992,47(10):471-475
Successful approach to depressed patients demands some knowledge of psychopathology, nosology and psychopharmacology. Some important aspects for practitioners of understanding and coping with depressives are given. An overview on the role of antidepressants (TCAs, selective serotonin re-uptake inhibitors, MAO-inhibitors) is also given. 相似文献
996.
Twenty-four-hour ambulatory blood pressure profiles in pediatric patients after renal transplantation 总被引:2,自引:2,他引:0
Nicolaus Lingens Eva Dobos Klaus Witte Christopher Busch Björn Lemmer Günther Klaus Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(1):23-26
Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been
transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure
recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to
116 (median 66) ml/min per 1.73 m2. Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements
in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was
reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only
patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was
not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure
in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate
an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied
in patients with renal transplants.
Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996 相似文献
997.
Hess B; Hasler-Strub U; Ackermann D; Jaeger P 《Nephrology, dialysis, transplantation》1997,12(7):1362-1368
BACKGROUND: Metabolic evaluation in recurrent idiopathic calcium renal
stone-formers (RCSF) was analysed with respect to the following questions:
(1) do three 24-h urines provide more diagnostic accuracy in the metabolic
evaluation of RCSF than 1 or 2 urines?; (2) does time after stone event
influence the diagnostic yield?; (3) is urine composition at weekends
different from that at mid-week?; (4) what are the prevalences of the most
important risk factors (RF) of idiopathic calcium nephrolithiasis, i.e. low
volume (LV), hypercalciuria (HC), hyperoxaluria (HO), hyperuricosuria (HU),
hypocitraturia (Hypo-Cit), and hypomagnesiuria (Hypo-Mg)?; and (5) do male
RCSF differ from females with respect to urinary RFs? METHODS: Seventy-five
RCSF (59 men, 16 women) collected three 24-h urines (U1-3) while on
free-choice diet. To account for possible variations in lifestyle and diet,
U1 and U3 had to be collected midweek and U2 at a weekend. RESULTS: When
considering all three urines together (U1 + U2 + U3), the number of RF
abnormalities/patient was 2.8 +/- 0.1, higher than numbers of any
combination of two urines or of any single urine (P = 0.0001 for all
comparisons). The number of RF abnormalities also rose with time after
stone event, from 0.8 +/- 0.1 (range 0-4) in U1 to 1.1 +/- 0.1 (range 0- 4)
in U3 (P = 0.011 vs U1). Whereas all other RF did not change between
collections, urine volume was lower in U2 (1793 +/- 90 ml) than in U1 (2071
+/- 97 ml, P = 0.0001 vs U2) and U3 (1946 +/- 97 ml, P = 0.046 vs U2). At
least 1 abnormality was found in 85.3% of all RCSF, and multiple
abnormalities occurred in 47%. The most frequent RF was HC (39%), followed
by HO and LV (32% each), Hypo-Cit (29%), HU (23%) and Hypo-Mg (19%). Males
more often had Hypo-Cit (P < 0.001) and Hypo-Mg (P < 0.01) than
females, whereas HO was more frequent in female RCSF (P < 0.025 vs
males). CONCLUSIONS: Diagnostic accuracy of metabolic evaluation in RCSF
increases both with the number of urines collected and the time passing
after a stone event. Urines collected at weekends differ from those of the
week only by their lower volumes. Abnormalities of RF for calcium
nephrolithiasis can be detected in 85.3% of RCSF, and HC is the most common
RF both in male and female RCSF.
相似文献
998.
From a group of 1,111 patients who had stapedectomy or stapedotomy performed in a 10-year period, a thorough investigation was made of 11 patients who had a total hearing loss and 8 patients who developed a partial sensorineural hearing loss after operation. The data obtained indicate that postoperative infection with influenza virus may be responsible for unexpected complications following stapedectomy. A close relation was found between the appearance of complications and periods of epidemics of influenza. 相似文献
999.
DNA polymerase beta mutations in human colorectal cancer. 总被引:15,自引:0,他引:15
Increasing numbers of alterations have been found in protooncogenes (e.g., ras, myc), as well as tumor suppressor genes (e.g., p53, Rb) in various types of tumors. The multiple mutations cannot be explained by the spontaneous mutation rate. It has been suggested that mutator phenotypes leading to the accumulation of these mutations may be required in the early stages of tumorigenesis. To test this hypothesis, the entire coding region of DNA polymerase beta, a repair enzyme, mRNA from colorectal tumors, and corresponding normal mucosa were amplified by polymerase chain reaction, cloned, and sequenced. Mutations in the catalytic domain of DNA polymerase beta were detected in colorectal tumor specimens compared to the normal colorectal mucosa, placenta, and blood samples. Since these mutations changed the structure of polymerase beta, it is expected that the efficiency of the DNA repair system would be impaired and thus may account for the high mutation rate observed in colorectal carcinomas. 相似文献
1000.
Gonadal function was evaluated in 25 boys treated for Hodgkin's disease according to the DAL-HD-85 protocol with OPA- or OPA/COMP-chemotherapy (vincristine-prednisone-adriamycine/cyclophosphamide-vincristine-m ethotrexate- prednisone). All boys were in first continuous complete remission for 6 to 45 months at chronological ages varying from 14.0 to 18.9 years. Testosterone, basal and GnRH-stimulated LH- and FSH-levels were measured. Gonadal function was normal in 16 patients treated with 2 cycles of OPA-chemotherapy in Hodgkin stages I-IIA. 9 patients were treated with 2 OPA- and 2 or 4 COMP-cycles of chemotherapy and had received mean cyclophosphamide doses ranging from 2004 to 3722 mg/m2. Again, no major testicular damage was noted, though some patients had increased stimulated LH-levels possibly indicating compensated Leydig cell-insufficiency. Our results demonstrate, that testicular function is not severely affected when patients are treated for Hodgkin's disease without procarbazine even if cyclophosphamide is given in cumulative doses below 3800 mg/m2. The previously documented severe testicular damage in boys treated according to the DAL-studies HD-78 and HD-82 is thus a result of the gonadotoxic action of procarbazine. 相似文献