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81.
 The cercarial emergence rhythms of Schistosoma mansoni were analyzed for mixed infection of the snail Biomphalaria glabrata with two chronobiological strains, one with an early shedding pattern and the other with a late shedding pattern. Under these conditions, each parasite strain kept its own circadian cercarial emergence pattern. When the chronobiological variants were of the same species, no interference between the trematode larvae occurred during the cercarial emergence process. These results confirm that within the host-parasite system the parasite component is directly responsible for the cercarial emergence pattern. Received: 16 September 1996 / Accepted: 18 October 1996  相似文献   
82.
Summary Preliminary results obtained from 26 cases of prolactinomas less than 20 mm in diameter after treatment by enlarged adenomectomy are described.The operation consisted in removal of the adenoma, a layer of normal pituitary at the outer edge of the tumour and the pituitary capsule in contact with the sellar meninges. 24 women and 2 men were involved whose prolactin levels (PRL) were less than 200 ng/ ml. All presented abnormal PRL responses to Thyrotropin releasing hormone (TRH) and Metoclopramide (MCP) tests and an absence of a nocturnal rise in the sleep cycle study. Postoperatively, three patients developed transitory diabetes insipidus and five transitory adrenal insufficiency. Gonadotropin reserve was always found normal. All 24 women resumed normal menstrual cycles and two became pregnant within one year. From a serological viewpoint, after surgery 100% of patients were found to be normal for levels of prolactin but only 85% turned to normal dynamic tests. The results of this small series of enlarged adenomectomies seem better than those obtained using selective adenomectomy, but must be confirmed with time.  相似文献   
83.
The cholinergic receptors in rabbit isolated rectus muscle preparations were characterized by means of cholinergic agonists and antagonists. The concentration-dependent contraction induced by acetylcholine, carbachol or oxotremorine remained uninfluenced by atropine (10(-5) M), whereas the nicotinic receptor antagonist hexamethonium caused a parallel shift of the concentration-response curve. The agonists pilocarpine, methacholine and aceclidine, which are selective muscarinic receptor stimulants, did not cause contraction of the muscle preparation. However, the nicotinic receptor stimulant 1,1-dimethyl-4-phenylpiperazine iodide (DMPP) caused contraction similar to that induced by acetylcholine. DMPP-induced contractions were inhibited by hexamethonium, causing a parallel rightward shift of the concentration-response curve. This shift could be quantified by means of a Schild plot, indicating competitive antagonism with a PA2 value of 4.63 for hexamethonium. Atropine when applied together with hexamethonium did not cause a further shift of the concentration-response curve. The present results clearly indicate that the cholinergic receptors which mediate contraction in the rabbit isolated extraocular muscle preparation belong to the nicotinic subtype.  相似文献   
84.
Zusammenfassung Experimentelle Untersuchungen haben für den maschinellen Bronchusverschluß nach Lobektomie und Pneumonektomie im Vergleich zu anderen Nahtmaterialien die geringste Entzündungsrate und die höchste Zugfestigkeit ergeben. In einer konsekutiven Serie von 233 Lungenresektionen der Chirurgischen Kliniken Köln-Lindenthal und der Klinik für Allgemein- und Abdominalchirurgie der Johannes Gutenberg-Universität Mainz ging die Häufigkeit einer Bronchus-stumpfinsuffizienz von 7,1% nach manuellem Bronchusverschluß auf 2,0% und die insuffizienzbedingte Letalität auf 0,7% bei Anwendung des Klammergeräts zurück. Die wesentlichen Vorteile des maschinellen Bronchusverschlusses sind die Einfachheit der Anwendung, die Schnelligkeit und die Gleichmäßigkeit des Verschlusses. Damit stellen die Klammernahtgeräte bei Lungenresektionen eine wertvolle Ergänzung der Operationstechnik dar.
Mechanical and manual bronchial closure —results of a consecutive trial
Summary After lobectomy and pneumonectomy in experimental evaluations stapled bronchial closures showed the lowest incidence of inflammatory reaction and the highest strength determined by leakage pressure compared with other suture material. A total of 233 lung resections - performed at Surgical University Clinic Köln-Lindenthal and the Clinic for General and Abdominal Surgery of the Johannes-Gutenberg-Universität Mainz — were reviewed. Mechanical stapling reduced the rate of bronchopleural fistulas to 2.0% compared with 7.1 % after manual suturing. In parallel, mortality related to bronchial stump leakage decreased to 0.7%. Main advantages of bronchial closure with staplers are the simplicity of their use, the speed and the uniformity of the closure. Thereby stapling devices are valuable completions in pulmonary surgery.
  相似文献   
85.
The muscle contents of water, electrolytes, creatine, alkali-soluble protein (ASP) and carnitine were determined using percutaneous muscle biopsy technique. Seven patients with prolonged catabolic states and subsequent respiratory failure were studied. Twelve age- and sex-matched healthy subjects were used for comparison. The muscle content of alkali-soluble protein in relation to the content of DNA was less than half of control values, indicating a loss of more than 50% of muscle protein content. The muscle carnitine content was 25.9 +/- 6.5 mumol/g alkali-soluble protein, suggesting a preserved muscle carnitine concentration. Total muscle water was increased by over 20%, mainly due to an increase in extracellular water. Muscle sodium and chloride contents were doubled. The content of magnesium was slightly reduced but muscle potassium was normal. The marked depletion of muscle protein may have contributed to the requirements for artificial ventilation and the difficulties in weaning off the ventilator. The increase in muscle water masks the loss of metabolically active muscle tissue yielding low values for energy expenditure when relating to body weight. The benefit of the use of the ASP/DNA ratio in nutritional assessment is emphasised.  相似文献   
86.
The effect of L-carnitine on FFA turnover and regional utilisation over the leg was investigated using infusion of (14)C-oleic acid and measurement of the respiratory quotient (RQ) in eight artificially ventilated patients with severe post-operative infection and at least 2 weeks of carnitine free TPN. Carnitine or placebo was added to the daily infusion of lipid during two consecutive 4-day periods in a randomised cross-over fashion. The total dose of carnitine was 110 mg/kg over 4 days. Before carnitine supplementation, total plasma carnitine levels ranged between 39 and 152 mumol/l. The RQ was 0.87 +/- 0.02 (SEM). The turnover (185 +/- 64 mumol/min) and fractional turnover (0.39 +/- 0.04/min) of oleic acid as well as the uptake (31 +/- 10 mumol/min) and fractional uptake (0.46 +/- 0.05) over the leg were similar to previously reported values in healthy subjects. Carnitine supplementation, despite a doubling of the average plasma carnitine level, did not influence the RQ or the whole body turnover and regional exchange of oleic acid. The present results suggest that four days of carnitine supplementation in patients with persistent post-operative infection has no measurable effect on FFA utilisation, indicating that the patients' carnitine reserves were sufficient to maintain normal FFA utilisation.  相似文献   
87.
Extravasation of leucocytes in tissues is mediated by leucocyte—endothelial cell interactions in which adhesion molecules play an important role. Until now, two pathways have been unravelled, i.e., the LFA-1/ICAM-1 and the VLA-4/VCAM-1 pathways. ELAM-1 has been shown to be involved in granulocyte accumulation and recently also in lymphocyte migration. The role of HECA-452 is under investigation. In this study we have investigated the expression of the above-mentioned adhesion molecules in lung tissue of patients with pulmonary sarcoidosis and usual interstitial pneumonitis (UIP), and in mediastinal lymph nodes of patients with sarcoidosis. ICAM-1 (CD54) was broadly distributed on the endothelium of all the vessels found in sarcoidosis and UIP. VCAM-1 was present on the endothelium of the venules, capillaries, and arterioles in both sarcoidosis and UIP. ELAM-1 reacted with endothelial cells lining venules and capillaries in chronic progressive sarcoidosis and in the active phase of UIP but not in the stationary phases of both diseases. HECA-452 activity could be detected only on high endothelial venules within sarcoid lymph nodes. In lung tissues, macrophages bearing the ICAM-1 antigen were present in sarcoid tissue but not in the interstitium and alveolar space of UIP. LFA-1 (CD11a/CD18) and VLA-4 (CD49d/CD29) were present on all leucocytes found but seemed to be more highly expressed on lymphocytes in sarcoidosis. These findings suggest that the LFA-1/ICAM-1 and VLA-4/VCAM-1 pathways are involved in leucocyte migration in both types of lung disease, while in the active phases of sarcoidosis and UIP, ELAM-1 is also involved.  相似文献   
88.
Zusammenfassung Späte Replikation an Chromosomen von Blut- oder Knochenmarkszellen mit Philadelphia-Chromosom von Kranken mit CML wurde in 6 Fällen autoradiographisch untersucht und mit Befunden an normalen kultivierten Lymphocyten verglichen.1. Mitosen von Leukämiezellen fanden sich erst nach relativ langer Anwesenheit von3H-Thymidin markiert, woraus sich für Zellen der CML eine längere G2-Phase als für kultivierte Lymphocyten ergab.2. Das Philadelphia-Chromosom wich in den meisten Zellen nicht wesentlich von den übrigen Chromosomen Nr. 21 und 22 ab und war autoradiographisch nicht sicher einem der beiden Paare zuzuordnen, in dem es zum Teil stärker mit dem spätreplizierenden und ebenso häufig mit dem früher replizierenden G-Chromosomenpaar übereinstimmte.3. Wie in der Lymphocytenkultur waren charakteristische Regionen der Autosomen Nr. 3–5 und 13–15 spät replizierend, wobei die Homologen weitgehend übereinstimmten.4. Feine Unterschiede in der Lokalisation der spätreplizierenden Zonen bzw. der maximalen Markierung gegenüber kultivierten Lymphocyten zeigten die Chromosomen Nr. 1 und 2. Diese Eigentümlichkeit wird im Hinblick auf die Auflösungsfähigkeit der Methode, die Spezifität hämatopoetischer Zellen des Knochenmarks und leukämisch entarteter Zellen im einzelnen besprochen.
Chromosome replication in chronic myelocytic leukemia cells
Summary Late replication in chromosomes from blood or bone marrow cells with the Philadelphia chromosome from patients with chronic myelocytic leukemia (CML) was studied autoradiographically in 6 cases. These observations were compared with the findings in normal cultivated lymphocytes. (1) Mitoses of leukemia cells were only found to be labelled after relatively long presence of3H-thymidine. Consequently, the G2 phase was longer for CML cells than for cultured lymphocytes. (2) In most instances the Philadelphia chromosome did not differ from the other chromosomes number 21 and 22. Autoradiographically it could not be classified as one of the two pairs. In the same number of cells this chromosome had a similar replication pattern compared to the later or the earlier replicating pair. (3) As in lymphocyte cultures, the characteristic regions of the autosomes number 3 to 5 and 13 to 15 were late replicating; in these instances the homologous autosomes were quite similar. (4) The chromosomes number 1 and 2 showed slight differences in the localization of late replicating areas or the highest labelling as compared to cultivated lymphocytes. These properties are discussed in detail as to the sensitivity of the method used, the specificity of haemopoietic cells of bone marrow and leukemia cells.


Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
89.
OBJECTIVE: To examine the efficacy and tolerability of a new matrix patch delivering estradiol (E2 Matrix) at doses of 0.05 and 0.10 mg per day (Estraderm MX 50, 100) in the treatment of moderate to severe postmenopausal symptoms. METHODS: A total of 254 postmenopausal women were randomized to receive treatment with E2 Matrix 0.10 mg (N = 86), E2 Matrix 0.05 mg (N = 82), or placebo (N = 86) in a double-blind, double-dummy fashion for a period of 12 weeks continuously. Patches were applied twice weekly to the buttocks with each patient wearing two patches at all times. The primary efficacy criterion was the difference from baseline of the mean number of moderate to severe hot flushes per 24 h during the last 2 weeks of treatment. Other efficacy variables included reduction in hot flushes at 4 and 8 weeks, reduction in daytime flushing and night sweats, and Kupperman Index at 4, 8, and 12 weeks. RESULTS: E2 Matrix 0.10 and 0.05 mg were both significantly superior to placebo in reducing hot flushes per 24 h after 4, 8, and 12 weeks of treatment (P < 0.001). Also, for all other efficacy parameters studied, both dosage strengths of E2 Matrix were statistically significantly superior to placebo at all time points (P < 0.001). Local tolerability was good in both groups. A slight increase in estrogen related adverse effects (breast tenderness, leukorrhoea) was seen with the 0.10 mg patch. Adhesion of patches and compliance were good. Overall systemic tolerability was good in both treated groups. However, a 4.8% overall incidence of endometrial hyperplasia was observed in patients with an intact uterus. CONCLUSIONS: This new matrix patch offers an effective and well tolerated dosage form for delivery of 0.05 and 0.1 mg estradiol per day. It may be particularly suitable for those women who experience local sensitivity to alcohol-containing systems. In light of the observed hyperplasia after treatment in five patients, estrogen therapy should as yet be supplemented monthly with a progestogen in women with an intact uterus.  相似文献   
90.
The activity of the IgH (Eµ) enhancer in the T lymphocytelineage has been investigated using both transgenic mice andtransfection studies. Thymocyte fractionation experiments indicatethat a transgene consisting of the bacterial chloramphenicolacetyl transferase (CAT) gene, linked to Eµ and the SV40early promoter (Eµ–CAT), is expressed only in thymocyteswith a mature medullary phenotype and not in immature cells.Transfection of this same construct into two thymoma cell linesrepresenting different stages of thymocyte development mimicsthe pattern of activity observed in vivo. Further transfectionexperiments suggest that this pattern of expression might beattributed to the differential activity of the E2E3 and octanucleotidemotifs of Eµ during development. In contrast, an Ig transgene(linked to Eµ and an Ig V promoter) is expressed in themajority of thymocytes. We envisage that the different patternsof expression of the two transgenes reflect interactions betweentheir respective promoters and the factors which are bound toEµ at different stages of thymocyte development. Althoughdiffering in their pattern of expression within the thymus,the two transgenes share the property of extinction in peripheralT lymphocytes. These results indicate that the expression ofEµ-linked transgenes in the thymus cannot simply be explainedby activation of the enhancer in a lymphoid progenitor cellprior to B/T lineage divergence. Rather, the enhancer (or componentsof it) must be independently activated (and inactivated) duringT lymphocyte development. Furthermore, this activity is consistentwith the developmental timing of Ig DH–JH rearrangementsin these cells.  相似文献   
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